Chem. Proc. , 2021, ECSOC-24

Luis Guillermo González-Olivares

Chem. Proc. 2021, 3(1), 4; https://doi.org/10.3390/ecsoc-24-08396 - 14 Nov 2020

Cited by 2 | Viewed by 627

Abstract

A series of three 2,5-Diketopiperazine (DKPs) were synthesized via one-pot process through the post- isocyanide-based multicomponent reactions (IMCR)-transformation strategy. This strategy emphasizes the role of orthogonal bifunctional reagents in the IMCR process to increase their synthetic potential, allowing us accessing a synthetic platform [...] Read more.

A series of three 2,5-Diketopiperazine (DKPs) were synthesized via one-pot process through the post- isocyanide-based multicomponent reactions (IMCR)-transformation strategy. This strategy emphasizes the role of orthogonal bifunctional reagents in the IMCR process to increase their synthetic potential, allowing us accessing a synthetic platform from which it is possible to obtain privileged heterocyclic peptidomimetics via lactamization reaction. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Crown Ether Benzoxazolyl-Alanines as Fluorimetric Chemosensors for the Detection of Palladium in Aqueous Environment

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Cátia D. F. Martins

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Patrícia M. R. Batista

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M. Manuela M. Raposo

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Susana P. G. Costa

Chem. Proc. 2021, 3(1), 5; https://doi.org/10.3390/ecsoc-24-08310 - 14 Nov 2020

Viewed by 612

Abstract

Palladium has wide application in different contexts and, as a consequence, high levels of palladium in the environment have been reported, representing a risk to human health. Considering the interest to develop more selective and sensitive chemosensors for this analyte, two novel benzoxazolyl-alanine [...] Read more.

Palladium has wide application in different contexts and, as a consequence, high levels of palladium in the environment have been reported, representing a risk to human health. Considering the interest to develop more selective and sensitive chemosensors for this analyte, two novel benzoxazolyl-alanine derivatives bearing a crown ether moiety were studied as potential fluorimetric chemosensors for palladium detection. Preliminary chemosensory studies for these unnatural amino acids in the presence of selected metal cations were performed in acetonitrile solution and in aqueous mixtures of sodium dodecyl sulfate (SDS, 20 mM, pH 7.5) solution with acetonitrile, 90:10 v/v. In acetonitrile solution, these probes had a fluorescence response for different cations but, most importantly, in SDS aqueous solution both compounds displayed a selective fluorescence response in the presence of palladium. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

A New Fluorogenic Substrate for Granzyme B Based on Fluorescence Resonance Energy Transfer

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Cátia D. F. Martins

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M. Manuela M. Raposo

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Susana P. G. Costa

Chem. Proc. 2021, 3(1), 6; https://doi.org/10.3390/ecsoc-24-08311 - 14 Nov 2020

Viewed by 692

Abstract

The synthesis and characterization of a new fluorogenic substrate for granzyme B (GzmB) is reported. The substrate design was based on the fluorescence resonance energy transfer (FRET) principle using 5-(2′-aminoethyl)aminonaphthalene sulfonic acid (Edans) and 4-[[4′-(N,N-dimethylamino)phenyl]diazenyl]benzoic acid (Dabcyl) as a [...] Read more.

The synthesis and characterization of a new fluorogenic substrate for granzyme B (GzmB) is reported. The substrate design was based on the fluorescence resonance energy transfer (FRET) principle using 5-(2′-aminoethyl)aminonaphthalene sulfonic acid (Edans) and 4-[[4′-(N,N-dimethylamino)phenyl]diazenyl]benzoic acid (Dabcyl) as a donor–acceptor pair, linked to a specific sequence for GzmB (AAD), with an additional amino acid as the anchoring point (K). The tetrapeptide was synthesized by microwave-assisted solid-phase peptide synthesis (MW-SPPS) and coupled to Dabcyl and Edans at its N- and C-termini, respectively. The obtained probe was purified by semi-preparative HPLC and characterized by NMR, UV/Vis absorption and fluorescence spectroscopy and mass spectrometry. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

A First Attempt to Identify Repurposable Drugs for Type 2 Diabetes: 3D-Similarity Search and Molecular Docking

by

Daniela Istrate

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Alina Bora

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Luminita Crisan

Chem. Proc. 2021, 3(1), 7; https://doi.org/10.3390/ecsoc-24-08368 - 14 Nov 2020

Viewed by 862

Abstract

Drug repositioning involves the investigation of existing drugs for new therapeutic purposes, such as type 2 diabetes. This disease affects the health and quality of life for individuals around the world. Sitagliptin, a highly selective dipeptidyl peptidase-4 (DPP-4) inhibitor, is used to treat [...] Read more.

Drug repositioning involves the investigation of existing drugs for new therapeutic purposes, such as type 2 diabetes. This disease affects the health and quality of life for individuals around the world. Sitagliptin, a highly selective dipeptidyl peptidase-4 (DPP-4) inhibitor, is used to treat type 2 diabetes mellitus by effective fasting and improved glycemic control. Despite this advantage, serious hypersensitivity reactions have been acknowledged for patients receiving sitagliptin. In this context, it is necessary to develop new drugs with enhanced profiles and targeting DPP-4. Sitagliptin, ((2R)-4-oxo-4-[3-(trifluoromethyl)-5,6-dihidro[1,2,4]triazolo[4,3-A]pirazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl)butan-2-amine), was used as a query in a 3D-similarity search on the approved DrugBank. Based on the TanimotoCombo parameter, the first 10 approved DrugBank drugs were docked in the 4FFW active site to identify effective antidiabetic effects for possible repurposable drugs marketed with other indications. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

In Silico Studies on Acetylcholine Receptor Subunit Alpha-L1 for Proposal of Novel Insecticides against Aphis craccivora

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Chem. Proc. 2021, 3(1), 8; https://doi.org/10.3390/ecsoc-24-08366 - 14 Nov 2020

Viewed by 629

Abstract

: Aphis craccivora is an aphid which damages many species of plants and is also a vector for numerous plant viruses. Since neonicotinoids are a well-known class of effective insecticides with less toxicity against mammals and other vertebrates, a small dataset of compounds [...] Read more.

: Aphis craccivora is an aphid which damages many species of plants and is also a vector for numerous plant viruses. Since neonicotinoids are a well-known class of effective insecticides with less toxicity against mammals and other vertebrates, a small dataset of compounds retrieved from the literature based on similarity to highly active neonicotinoids was used. Thus, homology modeling was involved in the building of the 3D structure of the acetylcholine receptor subunit alpha-L1 of Aphis craccivora. The homology model was involved in virtual screening experiments using the FRED docking tool of the OpenEye software. The aforementioned dataset was used to explore the intermolecular ligand–target interaction patterns for a rational design of desired and relatively safe insecticides. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Interactions of Alkyl Gallates with SARS-CoV-2 Main Protease: A Molecular Docking Approach

by

Amalia Stefaniu

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Lucia Pintilie

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Bujor Albu

and Lucia Pirvu

Chem. Proc. 2021, 3(1), 9; https://doi.org/10.3390/ecsoc-24-08360 - 14 Nov 2020

Viewed by 630

Abstract

Ten natural and semi-synthetic compounds (gallic acid and alkyl gallates) were investigated by in silico methods in order to evaluate their potential inhibitory activity against SAR-CoV-2 using the X-ray structure of SARS-CoV-2 main protease bound to Boceprevir at 1.45 Å (PDB ID: 6WNP). [...] Read more.

Ten natural and semi-synthetic compounds (gallic acid and alkyl gallates) were investigated by in silico methods in order to evaluate their potential inhibitory activity against SAR-CoV-2 using the X-ray structure of SARS-CoV-2 main protease bound to Boceprevir at 1.45 Å (PDB ID: 6WNP). The evaluation of drug-likeness in terms of Lipinski’s Rule of Five and docking results in terms of docking score and interactions with the amino acids residues from the active binding site of the target protein were reported. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

An In Silico Approach to Enzymatic Synthesis of Fucooligosaccharides Using α-l-Fucosidase from Thermotoga maritima

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Emmanuel Pérez-Escalante

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Araceli Castañeda-Ovando

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Alma Elizabeth Cruz-Guerrero

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John F. Trant

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Wendolyne López-Orozco

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Luis Humberto Mendoza-Huizar

and

Sergio Alatorre-Santamaría

Chem. Proc. 2021, 3(1), 10; https://doi.org/10.3390/ecsoc-24-08303 - 14 Nov 2020

Cited by 1 | Viewed by 786

Abstract

Fucooligosaccharides comprise the primary group of human milk oligosaccharides. Due to their beneficial properties, a series of synthetic methods have been proposed to obtain them. Enzymatic methods show great promise, and α-l-fucosidase from Thermotoga maritima has emerged as a powerful catalyst [...] Read more.

Fucooligosaccharides comprise the primary group of human milk oligosaccharides. Due to their beneficial properties, a series of synthetic methods have been proposed to obtain them. Enzymatic methods show great promise, and α-l-fucosidase from Thermotoga maritima has emerged as a powerful catalyst for their production. Nonetheless, the enzyme’s limited substrate scope has delayed its wider application. The present work aims to compare the relative reactivity of fucose, pNP-fucose, and ethyl-fucose, while also exploring the molecular interactions of these fucosyl-donors with the enzyme through a combination DFT and docking analysis. The HOMO-LUMO band gaps range from −7.14571 to −4.24429 eV, with α/β-pNP-fucose and α-fucose being the three most reactive compounds. Moderate association energies between −6.4 to −5.5 kcal·mol⁻¹ were found in the docking analysis, with α-pNP-fucose and both anomers of ethyl-fucose demonstrating the poorest affinity. In the case of α/β-lactose affinity to the β-fucose/enzyme complex, no significant differences were shown. We conclude that the best fucosyl-donors for transfucosylation are those that maintain an enzyme affinity and reactivity similar to pNP-fucose. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Design, Synthesis, and Photophysical Properties of BODIPY-Labeled Lupane Triterpenoids

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Chem. Proc. 2021, 3(1), 11; https://doi.org/10.3390/ecsoc-24-08102 - 13 Nov 2020

Viewed by 809

Abstract

Novel boron-dipyrromethene difluoride (4,4-difluoro-4-bora-3α,4α-diaza-s-indacene) (BODIPY)-lupane triterpenoid conjugates bearing a fluorescent marker at the C-2 position of ring A of the triterpene core were obtained via the Sonogashira reaction as a key step. The starting compounds in the cross-coupling reaction were C-2 propynyl derivatives [...] Read more.

Novel boron-dipyrromethene difluoride (4,4-difluoro-4-bora-3α,4α-diaza-s-indacene) (BODIPY)-lupane triterpenoid conjugates bearing a fluorescent marker at the C-2 position of ring A of the triterpene core were obtained via the Sonogashira reaction as a key step. The starting compounds in the cross-coupling reaction were C-2 propynyl derivatives of betulinic or betulonic acids and fluorescent dyes with an iodo-group at C-2 or meso position of BODIPY-platform. The newly elaborated coupling procedure might have applicability in the synthesis of fluorescently-labeled triterpenoid conjugates suitable for biological assays. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Evaluation of Reactivity (pKa) of Substituted Aromatic Diamines, Monomers for Polyamides Synthesis, via Nuclear Magnetic Resonance, NMR-¹H

by

Juan Enrique Tacoronte Morales

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María Teresa Cabrera Pedroso

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Joseph Cruel Siguenza

and

Carla Bernal Villavicencio

Chem. Proc. 2021, 3(1), 12; https://doi.org/10.3390/ecsoc-24-08436 - 14 Nov 2020

Cited by 1 | Viewed by 705

Abstract

The relationship between properties of aromatic polyamides and the structure and pKa of substituted diamine monomers allows for modeling and designing the synthesis of polymers with special properties for different uses (dialysis membranes, ion exchange systems, to thermo-resistant materials and impact protection devices). [...] Read more.

The relationship between properties of aromatic polyamides and the structure and pKa of substituted diamine monomers allows for modeling and designing the synthesis of polymers with special properties for different uses (dialysis membranes, ion exchange systems, to thermo-resistant materials and impact protection devices). Nuclear Magnetic Resonance is a versatile analytical tool for such purposes. Based on the obtained equations (pKa = 13.1512 − 1.67039 × (ppm)), and chemical shift (, ppm) = −7.0593 − (37.57628 × φ) the reactivity of the monomers can be calculated and selectively modify some properties of polyamides. Aromatic diamines were synthetized according to established protocols and statistical-molecular studies were developed using Hyperchem pack-2005 and Mopac-6. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

6-Amino-4-Aryl-3-Carbamoyl-5-Cyano-1,4-Dihydropyridine-2-Thiolates: Synthesis, Reactions and Docking Studies

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Nawras T. Jassim

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Chem. Proc. 2021, 3(1), 13; https://doi.org/10.3390/ecsoc-24-08394 - 14 Nov 2020

Viewed by 676

Abstract

New triethylammonium 6-amino-4-aryl-3-carbamoyl-5-cyano-1,4-dihydropyridine-2-thiolates were prepared in good yields by the ternary condensation of malononitrile, aldehydes and monothiomalonamide in the presence of Et₃N. The thiolates underwent S-alkylation under mild conditions to produce new 1,4-dihydronicotinamides. Molecular docking studies were carried out in order [...] Read more.

New triethylammonium 6-amino-4-aryl-3-carbamoyl-5-cyano-1,4-dihydropyridine-2-thiolates were prepared in good yields by the ternary condensation of malononitrile, aldehydes and monothiomalonamide in the presence of Et₃N. The thiolates underwent S-alkylation under mild conditions to produce new 1,4-dihydronicotinamides. Molecular docking studies were carried out in order to explore the interaction mechanism and to investigate suitable binding modes of the new compounds on the calcium channel proteins. Some of the compounds in the in silico experiments were found to be more potent as calcium channel blockers than the reference drug, Nifedipine. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

New Quinoxaline-1,4-Dioxides Derived from Beirut Reaction of Benzofuroxane with Active Methylene Nitriles

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Chem. Proc. 2021, 3(1), 14; https://doi.org/10.3390/ecsoc-24-08391 - 14 Nov 2020

Viewed by 669

Abstract

Benzofuroxane reacts under Beirut reaction conditions with active methylene nitriles to give new 2-aminoquinoxaline-1,4-dioxides. The treatment of known 2-amino-3-cyanoquinoxaline-1,4-dioxide with chloroacetyl chloride afforded corresponding chloroacetamide which is useful for the preparation of various heterocycles bearing a quinoxaline-1,4-dioxide core system. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Alkynyl N-BODIPYs as Reactive Intermediates for the Development of Dyes for Biophotonics

by

César Ray

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Andrés García-Sampedro

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Christopher Schad

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Edurne Avellanal-Zaballa

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Chem. Proc. 2021, 3(1), 15; https://doi.org/10.3390/ecsoc-24-08374 - 14 Nov 2020

Viewed by 603

Abstract

A new approach for the rapid multi-functionalization of BODIPY dyes towards biophotonics is reported. It is based on novel N-BODIPYs, through reactive intermediates with alkynyl groups to be further derivatized by click chemistry. This approach has been exemplified by the development [...] Read more.

A new approach for the rapid multi-functionalization of BODIPY dyes towards biophotonics is reported. It is based on novel N-BODIPYs, through reactive intermediates with alkynyl groups to be further derivatized by click chemistry. This approach has been exemplified by the development of new dyes for cell bio-imaging, which have proven to successfully internalize into pancreatic cancer cells and accumulate in the mitochondria. The in vitro suitability for photodynamic therapy (PDT) was also analyzed and confirmed our compounds to be promising PDT candidates for the treatment of pancreatic cancer. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

1′-Homocarbocyclic Nucleoside Analogs with an Optically Active Substituted Bicyclo[2.2.1]Heptane Scaffold

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Alexandrina Volobueva

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Ekaterina Sinegubova

Chem. Proc. 2021, 3(1), 16; https://doi.org/10.3390/ecsoc-24-08367 - 14 Nov 2020

Viewed by 596

Abstract

An optically active bicyclo[2.2.0]heptane fragment was introduced in the molecule of new 1′-homonucleosides on a 2- 6-chloro-amino-purine scaffold to obtain 6-substituted carbocyclicnucleozide analogs as antiviral compounds. The synthesis was realized by a Mitsunobu reaction of the base with the corresponding bicyclo[2.2.0]heptane intermediate, and [...] Read more.

An optically active bicyclo[2.2.0]heptane fragment was introduced in the molecule of new 1′-homonucleosides on a 2- 6-chloro-amino-purine scaffold to obtain 6-substituted carbocyclicnucleozide analogs as antiviral compounds. The synthesis was realized by a Mitsunobu reaction of the base with the corresponding bicyclo[2.2.0]heptane intermediate, and then the nucleoside analogs were obtained by substitution of the 6-chlorime with selected pharmaceutically accepted amines. A molecular docking study of the compounds on influenza, HSV and low active coronavirus was realized. Experimental screening of the compounds on the same viruses is being developed and soon will be finished. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Sustainable Synthesis of Polymeric Materials versus Fine Chemicals via CO₂ Addition to Epoxides

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Andreia C. S. Gonzalez

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Chem. Proc. 2021, 3(1), 17; https://doi.org/10.3390/ecsoc-24-08357 - 14 Nov 2020

Cited by 1 | Viewed by 652

Abstract

The development of efficient chemical processes capable of transforming carbon dioxide (CO₂) into value-added products constitutes one of the greatest challenges for the scientific community. In this context, the use of carbon dioxide as a C1 source is a relevant topic [...] Read more.

The development of efficient chemical processes capable of transforming carbon dioxide (CO₂) into value-added products constitutes one of the greatest challenges for the scientific community. In this context, the use of carbon dioxide as a C1 source is a relevant topic and, over the last decade, there has been remarkable scientific and technological advances regarding the development of chemical processes for converting CO₂into added value products. We highlight the reaction of CO₂ addition to epoxides, from which it is possible to selectively obtain two types of products: cyclic carbonates and polycarbonates, both with relevant applications as fine chemicals and polymeric materials, respectively. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Anionic Low Band Gap-Conjugated Polyelectrolytes as Hole-Transporting Layer in Optoelectronics Devices

by

Benedetta Maria Squeo

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Wojciech Mróz

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Umberto Giovanella

and

Mariacecilia Pasini

Chem. Proc. 2021, 3(1), 18; https://doi.org/10.3390/ecsoc-24-08406 - 14 Nov 2020

Viewed by 682

Abstract

In the last years, interfacial engineering has played a critical role in promoting the performance of optoelectronic devices as organic solar cells (OSC) and organic light-emitting diodes (OLEDs) since interfacial layers help to form an ohmic contact between the electrodes and the active [...] Read more.

In the last years, interfacial engineering has played a critical role in promoting the performance of optoelectronic devices as organic solar cells (OSC) and organic light-emitting diodes (OLEDs) since interfacial layers help to form an ohmic contact between the electrodes and the active layers, which is of great importance for charge collection/injection. Conjugated polyelectrolytes (CPEs), which are conjugated polymers bearing side-chain ionic functionalities such as anionic, cationic, or zwitterionic groups, have emerged as a new class of interfacial materials in thin film-based electronic devices thanks to their ability to reduce the barrier between electrode and active layer. In view of this, we designed and synthesized two novel low bandgap anionic copolymers with different anionic pendant groups and different conjugated backbones to obtain hole-transporting layer (HTL) materials as an alternative to commonly used poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate). The functional behavior of these copolymers as anode modifiers is herein preliminarily investigated in an OLED prototype. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Evaluation of Organophosphate Pesticide Residues in Food Using the Partial Least Squares Method

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Gheorghe Ilia

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Simona Funar-Timofei

Chem. Proc. 2021, 3(1), 19; https://doi.org/10.3390/ecsoc-24-08307 - 14 Nov 2020

Viewed by 587

Abstract

Organophosphorus (OP) chemicals were broadly used as insecticides and in the treatment of human diseases such as malaria mosquitoes, parasitosis, myasthenia, and glaucoma. The OP toxicity is well known. They can cause environmental and health problems and have the possibility to accumulate in [...] Read more.

Organophosphorus (OP) chemicals were broadly used as insecticides and in the treatment of human diseases such as malaria mosquitoes, parasitosis, myasthenia, and glaucoma. The OP toxicity is well known. They can cause environmental and health problems and have the possibility to accumulate in the food chain. The acceptable daily intake (ADI) can be considered as a measure of the effect of pesticide residues in food on human health. In this paper, the partial least squares (PLS) approach is used to evaluate the ADIs (expressed as pADIs) of a series of 46 structurally diverse OPs. OP structures were pre-optimized using the MMFF94s force field, and structural descriptors were calculated for the minimum energy conformers. This dataset was divided into 26 training compounds, and 20 pesticides were included in the prediction set. Several criteria to check the model robustness, overfitting, and the potential outliers in the X and Y space were employed. The PLS results indicated that new experimental toxicological data would be needed for five out of the 46 OPs, to improve their known ADI values, for qualitative and quantitative dietary long-term risk assessments. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Influence of Copper(I) Halides on the Reactivity of Aliphatic Carbodiimides

by

Valentina Ferraro

and

Marco Bortoluzzi

Chem. Proc. 2021, 3(1), 20; https://doi.org/10.3390/ecsoc-24-08096 - 13 Nov 2020

Cited by 1 | Viewed by 822

Abstract

The influence of copper(I) halides CuX (X = Cl, Br, I) on the electronic structure of N,N′-diisopropylcarbodiimide (DICDI) and N,N′-dicyclohexylcarbodiimide (DCC) was investigated by means of computational DFT (density functional theory) methods. The coordination of the considered [...] Read more.

The influence of copper(I) halides CuX (X = Cl, Br, I) on the electronic structure of N,N′-diisopropylcarbodiimide (DICDI) and N,N′-dicyclohexylcarbodiimide (DCC) was investigated by means of computational DFT (density functional theory) methods. The coordination of the considered carbodiimides occurs by one of the nitrogen atoms, with the formation of linear complexes having a general formula of [CuX(carbodiimide)]. Besides varying the carbon–nitrogen bond lengths, the thermodynamically favourable interaction with Cu(I) reduces the electron density on the carbodiimides and alters the energies of the (NCN)-centred, unoccupied orbitals. A small dependence of these effects on the choice of the halide was observable. The computed Fukui functions suggested negligible interaction of Cu(I) with incoming nucleophiles, and the reactivity of carbodiimides was altered by coordination mainly because of the increased electrophilicity of the {NCN} fragments. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

New Dibenzofuran Compounds Obtained by Dihydrousnic Acid Hydrogenation

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Aleksandr Filimonov

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Olga Luzina

and

Nariman Salakhutdinov

Chem. Proc. 2021, 3(1), 21; https://doi.org/10.3390/ecsoc-24-08460 - 16 Nov 2020

Viewed by 866

Abstract

It has been found that usnic acid carbonyl groups can be hydrogenated by the action of H₂/Pd(C). Thus, two new dibenzofuran derivatives were synthesized. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Identification of Less Harmful Pesticides against Honey Bees: Shape-Based Similarity Analysis

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Chem. Proc. 2021, 3(1), 22; https://doi.org/10.3390/ecsoc-24-08342 - 14 Nov 2020

Viewed by 621

Abstract

The high concentration of pesticide residues existing in vegetation, crops, and various edible products and the prolonged exposure to them can harm human life and contribute to the disappearance of honey bees, and several avian and animal species. The honey bees (Apis mellifera), [...] Read more.

The high concentration of pesticide residues existing in vegetation, crops, and various edible products and the prolonged exposure to them can harm human life and contribute to the disappearance of honey bees, and several avian and animal species. The honey bees (Apis mellifera), which are efficient pollinators in addition to honey producers, are also considered important non-target test species for the terrestrial toxicity assessment of chemicals. In this context, using thiacloprid and acetamiprid as queries, we performed a 3D similarity search to select new potential products with less harmful effects against bees. For a similarity search, a small dataset of 302 compounds with pesticide activity, compiled from the literature, was used. The first 10 compounds were selected and structurally analyzed according to the TanimotoCombo metrics, and compared with each of these two queries, which is known to be effective, easily metabolized, and less toxic for bees. This approach came as a forward step in the research of pesticide ecotoxicological risk assessment for the evaluation of their potential impact on the pollinator insects and the environment. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

New Reactions of 5-Amino-3-(Cyanomethyl)-1H-Pyrazole-4-Carbonitrile

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Aminat M. Semenova

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Chem. Proc. 2021, 3(1), 23; https://doi.org/10.3390/ecsoc-24-08398 - 14 Nov 2020

Viewed by 550

Abstract

5-Amino-3-(cyanomethyl)-1H-pyrazole-4-carbonitrile, prepared by reaction of malononitrile dimer with hydrazine, smoothly reacts with chloroacetyl chloride to form 2-chloro-N-(4-cyano-3-(cyanomethyl)-1H-pyrazol-5-yl)acetamide in good yield. The latter easily reacts with 3-cyanopyridine-2-thiolates to give hybrid molecules bearing nicotinonitrile and pyrazole units. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Synthesis of New Water-Soluble Bunte Salts Bearing Thieno[2,3-b]Pyridine-3-yl Substituents

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Chem. Proc. 2021, 3(1), 24; https://doi.org/10.3390/ecsoc-24-08397 - 14 Nov 2020

Viewed by 997

Abstract

Upon treatment with chloroacetyl chloride, 3-aminothieno[2,3-b]pyridines gave the corresponding chloroacetamides. The latter readily react with sodium thiosulphate to afford water soluble S-alkylthiosulphates with pharmacophoric heterocyclic units. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

In Silico Study of Some Natural Flavonoids as Potential Agents against COVID-19: Preliminary Results

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Alina Bora

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Liliana Pacureanu

and

Luminita Crisan

Chem. Proc. 2021, 3(1), 25; https://doi.org/10.3390/ecsoc-24-08343 - 14 Nov 2020

Cited by 2 | Viewed by 804

Abstract

Flavonoids, widely distributed in fruits, vegetables, and medicinal herbs, are compounds with multiple biological benefits to human health from anti-inflammatory, antioxidant, anticancer, antibacterial to antiviral activity. Coronavirus disease 2019 (COVID-19), a serious concern in the world today, is a respiratory tract disease involving [...] Read more.

Flavonoids, widely distributed in fruits, vegetables, and medicinal herbs, are compounds with multiple biological benefits to human health from anti-inflammatory, antioxidant, anticancer, antibacterial to antiviral activity. Coronavirus disease 2019 (COVID-19), a serious concern in the world today, is a respiratory tract disease involving moderate to severe symptoms of pneumonia, with a major incidence in older people and patients having chronic diseases. This emergency health situation led us to evaluate the possible use of natural products to prevent respiratory diseases. The present study aims to report the potential of four natural flavonoids, known to have anti-inflammatory and antiviral activity, as anti-SARS-CoV-2 through their binding on the 6YNQ protein receptor. Molecular docking study with the FRED program was chosen as an appropriate tool to analyze the interaction of natural flavonoids, quercetin, luteolin, galangin, and naringenin, with the SARS-CoV-2 main protease and to rank the conformations through a scoring function to predict their binding affinity. Overall, our preliminary results indicate the potential of the titled natural flavonoids to fight the new coronavirus, COVID-19. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

The Reactions of N,N′-Diphenyldithiomalonamide with Michael Acceptors

by

Anna E. Sinotsko

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and

Raúl Eduardo Gordillo-Cruz

Chem. Proc. 2021, 3(1), 26; https://doi.org/10.3390/ecsoc-24-08399 - 14 Nov 2020

Viewed by 542

Abstract

N,N′-diphenyldithiomalonamide (dithiomalondianilide) smoothly reacts with various Michael acceptors to give either stable Michael adducts or products of their further heterocyclization. The structure of the products was confirmed by 2D NMR experiments and X-ray data. The mechanisms of the reactions are discussed. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Microwave-Assisted Asinger Synthesis of Thiazolines

by

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Liliana Gonzalez-Reyes

,

Milton Coporo-Reyes

,

Nieves Zavala-Segovia

,

Bernardo A. Frontana-Uribe

,

Marco A. García-Eleno

,

M. V. Basavanag Unnamatla

and

Erick Cuevas-Yañez

Chem. Proc. 2021, 3(1), 27; https://doi.org/10.3390/ecsoc-24-08316 - 14 Nov 2020

Viewed by 712

Abstract

An array of 2,4-disubstituted thiazolines was obtained through Asinger reaction approach from the straightforward treatment of diverse aldehydes/ketones with 1-mercaptopropan-2-one, in the presence of NH₃ assisted by microwave irradiation, displaying similar and sometimes higher yields, as well as shorter reaction times that [...] Read more.

An array of 2,4-disubstituted thiazolines was obtained through Asinger reaction approach from the straightforward treatment of diverse aldehydes/ketones with 1-mercaptopropan-2-one, in the presence of NH₃ assisted by microwave irradiation, displaying similar and sometimes higher yields, as well as shorter reaction times that traditional Asinger reaction conditions at room and lower temperatures. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Thiomonosaccharide Derivatives from D-Mannose

by

Marcos Díaz-Fernández

and

M. Soledad Pino-González

Chem. Proc. 2021, 3(1), 28; https://doi.org/10.3390/ecsoc-24-08424 - 14 Nov 2020

Viewed by 638

Abstract

Sulfur-containing monosaccharide derivatives can be highly valuable for obtaining compounds with biological activities. In this work, a synthetic route starting from D-mannose has been designed. After a convenient hydroxyl protection and anomeric carbon functionalization in a cyano group, a new carbohydrate analogue has [...] Read more.

Sulfur-containing monosaccharide derivatives can be highly valuable for obtaining compounds with biological activities. In this work, a synthetic route starting from D-mannose has been designed. After a convenient hydroxyl protection and anomeric carbon functionalization in a cyano group, a new carbohydrate analogue has been obtained with sulfur in the ring. The heteroatoms have been introduced by an S_N2 mechanism, with subsequent cyclization. Structural identification has been performed by different spectroscopic techniques. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Synthesis and Photophysical Characterization of 2′-Aminochalcones

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Chem. Proc. 2021, 3(1), 29; https://doi.org/10.3390/ecsoc-24-08301 - 14 Nov 2020

Viewed by 656

Abstract

Chalcones present biological activity and are, therefore, currently studied for their therapeutic potential. They have shown antitumor, anti-inflammatory, antifungal and antibacterial properties. These compounds occur in nature as secondary metabolites of plants and are precursors of flavonoid biosynthesis. Generally, they are not luminescent, [...] Read more.

Chalcones present biological activity and are, therefore, currently studied for their therapeutic potential. They have shown antitumor, anti-inflammatory, antifungal and antibacterial properties. These compounds occur in nature as secondary metabolites of plants and are precursors of flavonoid biosynthesis. Generally, they are not luminescent, but derivatives with some particular patterns of substitution can present fair quantum yields. Excited State Intramolecular Proton Transfer (ESIPT) is a particular case of tautomerization, and some molecules can exhibit ESIPT fluorescence if their structures incorporate an intramolecular hydrogen bonding interaction between a hydrogen donor (-OH or -NH) and a hydrogen acceptor. If the dye is fluorescent, emission from both tautomers may be observed, leading to a dual emission. The chalcones with a strong push–pull character, compounds 2c, 3c and 4c, presented dual emission of keto–enol tautomerism as a consequence of ESIPT. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

The Aminometylation of 4-(Alkylthio)-6-amino-2-oxo(thioxo)-1,2-dihydropyridine-3,5-dicarbonitriles

by

Ekaterina A. Khrapova

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Natalya A. Ryzhkova

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and

Chem. Proc. 2021, 3(1), 30; https://doi.org/10.3390/ecsoc-24-08401 - 14 Nov 2020

Viewed by 502

Abstract

Easily available 2-(bis(alkylthio)methylene)malononitriles react with cyanoacetamide or cyanothioacetamide to give 4-(alkylthio)-6-amino-2-oxo(thioxo)-1,2-dihydropyridine-3,5-dicarbonitriles. Upon treatment with primary amines and/or HCHO, the compounds undergo heterocyclization to afford new pyrido[1,2-a][1,3,5]triazines or ring-condensed 1,3,5,7-tetrazocine derivatives. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

In Silico Screening of Agonist and Antagonist Natural Compounds from Reported Essential Oils against Bursaphelenchus xylophilus

by

Jorge M. S. Faria

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Ana Margarida Rodrigues

,

Pedro Barbosa

and

Manuel Mota

Chem. Proc. 2021, 3(1), 31; https://doi.org/10.3390/ecsoc-24-08386 - 14 Nov 2020

Cited by 3 | Viewed by 566

Abstract

Chemical control has been the most effective and reliable containment strategy in integrated pest management of pine wilt disease (PWD), caused by the pinewood nematode (PWN), Bursaphelenchus xylophilus. Yet, large spectrum nematicides can be dangerous to human health and the environment. Essential [...] Read more.

Chemical control has been the most effective and reliable containment strategy in integrated pest management of pine wilt disease (PWD), caused by the pinewood nematode (PWN), Bursaphelenchus xylophilus. Yet, large spectrum nematicides can be dangerous to human health and the environment. Essential oils (EOs) are safer sustainable alternatives, being composed of highly active natural compounds. A survey of bibliographic data on the detailed chemical composition and activity of the EOs used against the PWN allowed pinpointing monoterpenes as the main source of structures with agonist or antagonist properties. Transversal EO data treatment can identify potential highly active anti-PWN compounds. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Preparation and Hydro-Lipophilic Properties of Novel Fluorinated Benzyl Carbamates of 4-Aminosalicylanilides

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Chem. Proc. 2021, 3(1), 32; https://doi.org/10.3390/ecsoc-24-08094 - 13 Nov 2020

Viewed by 635

Abstract

A series of seven fluorinated benzyl carbamates of 4-aminosalicylanilides and unsubstituted benzyl [3-hydroxy-4-(phenylcarbamoyl)phenyl]carbamate designed as agents with the expected anticholinesterase and anti-inflammatory activity were prepared and characterized. As lipophilicity significantly influences the biological activity of compounds, the hydro-lipophilic properties of these mono-, di-, [...] Read more.

A series of seven fluorinated benzyl carbamates of 4-aminosalicylanilides and unsubstituted benzyl [3-hydroxy-4-(phenylcarbamoyl)phenyl]carbamate designed as agents with the expected anticholinesterase and anti-inflammatory activity were prepared and characterized. As lipophilicity significantly influences the biological activity of compounds, the hydro-lipophilic properties of these mono-, di-, and tri-substituted carbamates were investigated in this study. All the discussed derivatives of 4-{[(benzyloxy)carbonyl]amino}-2-hydroxybenzoic acid were analyzed using reversed-phase high performance liquid chromatography to measure lipophilicity. The procedure was performed under isocratic conditions with methanol as an organic modifier in the mobile phase using an end-capped non-polar C₁₈ stationary reversed-phase column. In the present study, the correlations between the logarithm of the capacity factor k, the logarithm of the distributive parameter D at pH 7.4, and log P/Clog P values calculated in various ways as well as the relationships between the lipophilicity and the chemical structure of the studied compounds are discussed. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Comparative Studies of Various NNRTIs in the Active Site of Different HIV-1RT Receptors

by

Priyanka Chandra

,

Swastika Ganguly

and

Soikata Karmakar

Chem. Proc. 2021, 3(1), 33; https://doi.org/10.3390/ecsoc-24-08313 - 14 Nov 2020

Cited by 1 | Viewed by 663

Abstract

HIV is one of the most deadly viruses known to humans and causes a disease, known as Acquired Immunodeficiency Syndrome (or, AIDS). There are only a handful of drugs which are totally effective against the virus. This is due to the enzyme reverse [...] Read more.

HIV is one of the most deadly viruses known to humans and causes a disease, known as Acquired Immunodeficiency Syndrome (or, AIDS). There are only a handful of drugs which are totally effective against the virus. This is due to the enzyme reverse transcriptase present within the virus. Due to various mutations in the enzyme, the virus becomes unresponsive towards the drugs. In the present study, docking studies of the standard non-nucleoside reverse transcriptase inhibitors were performed in the non-nucleoside inhibitory binding pocket of reverse transcriptase enzymes of wild type and the resistant strains of HIV-1RT virus with PDB IDs 1RT2, 1KLM, 3BGR, and 1JLB, respectively, by using Autodock version 4.5.6. A comparison of different compounds docked into the active site of various HIV-1RT strains was carried out. The obtained results indicate that most of the compounds docked into the active site of the different receptors, such as 1RT2, 1KLM, 3BGR, and 1JLB, with good docking scores, are comparable to that of the internal standard (TNK 651) of the wild type strain of HIV-1 virus. A comparison was made based on the binding modes of the compounds in the active site of all the four receptors. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

On the Acylation of 1,6-Diamino-2-oxo-1,2-dihydropyridine-3,5-dicarbonitriles

by

Alexandra R. Chikava

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Alexei A. Dolganov

and

Chem. Proc. 2021, 3(1), 34; https://doi.org/10.3390/ecsoc-24-08315 - 14 Nov 2020

Viewed by 478

Abstract

Here, 1,6-diamino-2-oxo-1,2-dihydropyridine-3,5-dicarbonitriles, prepared by the reaction of cyanoacethydrazide with arylmethylene malononitriles, react with 1-cyanoacetyl-3,5-dimethylpyrazole and chloroacetyl chloride to give corresponding cyanoacetamides and chloroacetamides. The reaction with phthalic anhydride proceeds under harsh conditions to give 4,7-dioxo-4,7-dihydropyrido[1′,2′:2,3][1,2,4]triazolo[5,1-a]isoindole- 1,3-dicarbonitriles. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Stable Anionic σ-Complexes of Highly Electrophilic Aromatics and C-Nucleophiles: Synthesis and Oxidation

by

Alexey Starosotnikov

,

Maxim Bastrakov

and

Vladimir Kokorekin

Chem. Proc. 2021, 3(1), 35; https://doi.org/10.3390/ecsoc-24-08437 - 15 Nov 2020

Viewed by 789

Abstract

Reactions of dinitrobenzoannulated heterocycles (furazan, thiadiazole, selenadiazole, pyridine) with anionic C-nucleophiles (mono- and diketones, nitroalkanes and related compounds) provided stable anionic adducts in high yields. Consecutive oxidation with ammonium cerium (IV) nitrate resulted in re-aromatization with the formation of the corresponding substitution products, [...] Read more.

Reactions of dinitrobenzoannulated heterocycles (furazan, thiadiazole, selenadiazole, pyridine) with anionic C-nucleophiles (mono- and diketones, nitroalkanes and related compounds) provided stable anionic adducts in high yields. Consecutive oxidation with ammonium cerium (IV) nitrate resulted in re-aromatization with the formation of the corresponding substitution products, formally representing C-H-functionalized benzoheterocycles. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Synthesis and Insecticidal Activity of O-alkylated Oxirane Eugenol Derivatives

by

Maria José G. Fernandes

,

David M. Pereira

,

Renato B. Pereira

,

A. Gil Fortes

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and

Chem. Proc. 2021, 3(1), 36; https://doi.org/10.3390/ecsoc-24-08335 - 14 Nov 2020

Viewed by 759

Abstract

The synthesis of three O-alkylated eugenol derivatives, bearing a hydroxypropyl chain and propyl esters, were synthesized and further converted into the corresponding oxiranes. Oxirane derivatives were then evaluated against their effect upon the viability of the insect cell line Sf9 (Spodoptera [...] Read more.

The synthesis of three O-alkylated eugenol derivatives, bearing a hydroxypropyl chain and propyl esters, were synthesized and further converted into the corresponding oxiranes. Oxirane derivatives were then evaluated against their effect upon the viability of the insect cell line Sf9 (Spodoptera frugiperda), in comparison with the starting O-alkylates. The results pointing to their potential as bioinsecticides, with structural changes eliciting significant effects in terms of potency. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Carvacrol Derivatives with Potential Insecticidal Activity

by

Carolina M. Natal

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David M. Pereira

,

Renato B. Pereira

,

Maria José G. Fernandes

,

A. Gil Fortes

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and

Chem. Proc. 2021, 3(1), 37; https://doi.org/10.3390/ecsoc-24-08334 - 14 Nov 2020

Cited by 1 | Viewed by 666

Abstract

Three new carvacrol derivatives 1–3 possessing aliphatic carbon chains with different sizes as hydroxyl group substituents were synthesized in order to evaluate their insecticidal activity against the insect cell line Sf9 (Spodoptera frugiperda). Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

A Study about the Use of Co or Mn-Based Nanocatalysts for Styrene Epoxidation Reaction

by

Lucía Rossi-Fernández

,

Leandro Aguilar

,

Viviana Dorn

and

Gabriel Radivoy

Chem. Proc. 2021, 3(1), 38; https://doi.org/10.3390/ecsoc-24-08312 - 14 Nov 2020

Viewed by 488

Abstract

A new catalytic system consisting of Mn or Co nanoparticles supported on different materials (celite, zeolite, activated carbon, CeO₂, ZnO, MgO, Nb₂O₅) have been studied for styrene epoxidation. The catalysts were easily prepared from commercially available starting [...] Read more.

A new catalytic system consisting of Mn or Co nanoparticles supported on different materials (celite, zeolite, activated carbon, CeO₂, ZnO, MgO, Nb₂O₅) have been studied for styrene epoxidation. The catalysts were easily prepared from commercially available starting materials. Reaction conditions were optimized by testing different solvents, reaction temperatures, oxidizing agents, and optimal catalyst loading. CoNPs/MgO and TBHP as a co-oxidant, in refluxing ACN, allowed total conversion to the epoxide with excellent yield and high selectivity. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Nanosystems for the Encapsulation and Release of Plant Extracts with Insecticidal Activity

by

Ana I. F. Lopes

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David M. Pereira

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A. Gil Fortes

and

Florencia Antonella Musso

Chem. Proc. 2021, 3(1), 39; https://doi.org/10.3390/ecsoc-24-08332 - 14 Nov 2020

Viewed by 705

Abstract

Encapsulation in suitable nanostructures is a relevant strategy for the preservation and controlled release of bioactive compounds, allowing a safe application. In this work, dichloromethane extracts of Mentha suaveolens Ehrh. and Phytolacca americana L. were encapsulated in chitosan nanostructures and liposomes of soybean [...] Read more.

Encapsulation in suitable nanostructures is a relevant strategy for the preservation and controlled release of bioactive compounds, allowing a safe application. In this work, dichloromethane extracts of Mentha suaveolens Ehrh. and Phytolacca americana L. were encapsulated in chitosan nanostructures and liposomes of soybean lecithin, considering their potential as biopesticides. Liposomes were prepared either by thin film hydration or ethanolic injection methods. For chitosan, the ionic gelation technique was used. The nanosystems were characterized regarding their size and polydispersity. Encapsulation efficiencies of the extracts were determined (being higher than 60%) and the release profiles were measured. Liposomes generally allowed a delayed release of the extracts, while chitosan nanosystems were suitable for a faster and complete release of the potential bioinsecticides. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Fluorescent Calix[4]arene-Oxacyclophane Sensor for Transition Metal Cations

by

Alexandra I. Costa

,

Patrícia D. Barata

and

José V. Prata

Chem. Proc. 2021, 3(1), 40; https://doi.org/10.3390/ecsoc-24-08453 - 16 Nov 2020

Viewed by 876

Abstract

The sensing behavior of a calix[4]arene-oxacyclophane-carbazole conjugate (1) towards Cu(I) ions was investigated. Contrary to the noteworthy sensitivity and selectivity previously found for Cu(II), the affinity of 1 for Cu(I) cations is much lower. Through fluorescence titration assays, the apparent binding [...] Read more.

The sensing behavior of a calix[4]arene-oxacyclophane-carbazole conjugate (1) towards Cu(I) ions was investigated. Contrary to the noteworthy sensitivity and selectivity previously found for Cu(II), the affinity of 1 for Cu(I) cations is much lower. Through fluorescence titration assays, the apparent binding constants (K_a) for the two ions were determined, showing that an affinity of over thirteen fold was displayed for Cu(II). Two Cu(I) counter-ions were used to determine possible effects on the binding event. It was found that acetate and iodide ions behave similarly, yielding K_a of the same magnitude. Formation of a ground-state supramolecular complex between 1 and Cu(I) ions was not observed on UV-Vis titrations, in contrast to what was previously reported for Cu(II) using the same host. The affinity of 1 for Fe(III), a major biological competitor, was also assessed. The fluorescence of host 1 is quenched by Fe(III) ions although to a lesser extent (32% less efficient than Cu(II)). The study demonstrates that calixarene 1 is able to differentiate copper ions in two common oxidation states using fluorescence techniques, thereby suggesting its application for redox-active centers in biomimetic chemistry. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Synthesis and Preliminary Antibacterial Evaluation of A 2,4,5-Tri(hetero)arylimidazole Derivative

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Chem. Proc. 2021, 3(1), 41; https://doi.org/10.3390/ecsoc-24-08331 - 14 Nov 2020

Cited by 1 | Viewed by 593

Abstract

The imidazole ring is a planar heterocycle whose derivatives are applied in several scientific areas, such as medicinal, materials and supramolecular chemistry. The presence of the imidazole ring in these structures is the key to the development of new drugs, since it is [...] Read more.

The imidazole ring is a planar heterocycle whose derivatives are applied in several scientific areas, such as medicinal, materials and supramolecular chemistry. The presence of the imidazole ring in these structures is the key to the development of new drugs, since it is ubiquitous in naturally occurring biological structures. Therefore, over the past few decades, several imidazole derivatives have been synthesized and occupy a unique position in the field of medicinal chemistry due to their diverse biological activities. In order to continue the work developed by the research group, we report the synthesis of 2,4,5-tri(hetero)arylimidazole derivatives and their characterization by ¹H and ¹³C nuclear magnetic resonance (NMR) and UV-Vis absorption spectroscopies. As a complement to the characterization of the synthesized 2,4,5-tri(hetero)arylimidazole derivatives, a screening for antibacterial activity showed the inhibition of Staphylococcus aureus proliferation, suggesting antibacterial activity. Therefore, these new compounds have the potential for the development of new drugs. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Stokesia laevis Ethanolic Extract Activity on the Normal and Malignant Murine Cell Line Viability L969 and B16

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Chem. Proc. 2021, 3(1), 42; https://doi.org/10.3390/ecsoc-24-08318 - 14 Nov 2020

Cited by 1 | Viewed by 533

Abstract

: Stokesia laevis (common name Stokes aster) ethanolic extract (Slae26) containing 5 mg GAE/mL extract was investigated to establish cytotoxicity and anti-proliferative effects. The assays were performed on normal murine fibroblast cell line L929 and malignant murine melanoma cell line B16, respectively; for [...] Read more.

: Stokesia laevis (common name Stokes aster) ethanolic extract (Slae26) containing 5 mg GAE/mL extract was investigated to establish cytotoxicity and anti-proliferative effects. The assays were performed on normal murine fibroblast cell line L929 and malignant murine melanoma cell line B16, respectively; for the first time in literature data, potential cytotoxic and anti-proliferative effects of the ethanolic extract from S. laevis on both, normal murine fibroblast cell line L929, and murine melanoma cell line B16 have been proved. The study is supplemented by molecular docking simulations of the major components of Slae26 against human tyrosinase receptor, to evaluate possible melanogenesis inhibition. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Synthesis of Myrtenal through Allylic Oxidation of α-Pinene over a Pd/SeO₂/SiO₂ Catalyst

by

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Victoria Soledad Gutiérrez

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María Alicia Volpe

and

María Belén Faraoni

Chem. Proc. 2021, 3(1), 43; https://doi.org/10.3390/ecsoc-24-08382 - 14 Nov 2020

Viewed by 960

Abstract

SeO₂ based samples are tested for the oxidation of α-pinene, in liquid phase employing ethanol as the solvent. Commercial SeO₂ was tested under both reflux and under 6 atm O₂ pressure. At conversion levels of approximately 40%, the yield to [...] Read more.

SeO₂ based samples are tested for the oxidation of α-pinene, in liquid phase employing ethanol as the solvent. Commercial SeO₂ was tested under both reflux and under 6 atm O₂ pressure. At conversion levels of approximately 40%, the yield to myrtenal was much higher in the latter (34.4%) than in the former case (18.0%) due to the high oxidant species availability. Besides the high yield attained at relatively short reaction time. A palladium promoted selenium dioxide supported catalyst (Pd/SeO₂/SiO₂) was prepared, characterized, and submitted to the catalytic test. Selenium dioxide (14.4%) was strongly fixed to the silica support. Upon the palladium introduction (0.98%), the reducibility of SeO₂ is modified, which originates a selenium species activation towards the allylic oxidation. A 12% conversion level is attained over Pd/SeO₂/SiO₂ following 8 h of reaction time, employing ethanol as the solvent at 134 °C. The main product is myrtenal, being obtained with a selectivity of 62%. Over oxidation products are not detected. The palladium/selenium dioxide sample is easy to handle with and its recuperation following the reaction in liquid phase is possible. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Synthesis of Tetrakis-Tetrazole via a Repetitive MCR

by

Sandra C. Ramírez-López

,

Àngel Rentería-Gómez

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Luis E. Cárdenas Galindo

and

M. V. Basavanag Unnamatla

Chem. Proc. 2021, 3(1), 44; https://doi.org/10.3390/ecsoc-24-08395 - 14 Nov 2020

Viewed by 560

Abstract

The synthesis of novel and complex molecules of tetrakis-tetrazole was done via a Ugi-azide repetitive reaction from easily accessible starting materials in good yields. The use of orthogonal bifunctional reagents in isocyanide-based multicomponent reactions (IMCR) allowed the synthesis of structurally complex molecules in [...] Read more.

The synthesis of novel and complex molecules of tetrakis-tetrazole was done via a Ugi-azide repetitive reaction from easily accessible starting materials in good yields. The use of orthogonal bifunctional reagents in isocyanide-based multicomponent reactions (IMCR) allowed the synthesis of structurally complex molecules in one pot manner. The molecules herein synthesized could have applications such as use as chelating agents and organocatalysts. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Glucose-Based Molecular Rotors as Fluorescent Inhibitors and Probes of Glycogen Phosphorylase

by

Konstantinos F. Mavreas

,

Michael Mamais

,

Panagiota Papazafiri

and

Thanasis Gimisis

Chem. Proc. 2021, 3(1), 45; https://doi.org/10.3390/ecsoc-24-08414 - 14 Nov 2020

Cited by 1 | Viewed by 739

Abstract

In this study, (E)-2-cyano-3-(6-(dimethylamino)naphthalen-2-yl)-N-(β-d-glucopyranosyl)acrylamide, a β-d-glucopyranosyl analogue of the widely used molecular rotor julolidine, was synthesized and studied photochemically. The new compound is a fluorescent inhibitor of rabbit muscle glycogen phosphorylase with properties of a molecular rotor. Fluorescence measurements [...] Read more.

In this study, (E)-2-cyano-3-(6-(dimethylamino)naphthalen-2-yl)-N-(β-d-glucopyranosyl)acrylamide, a β-d-glucopyranosyl analogue of the widely used molecular rotor julolidine, was synthesized and studied photochemically. The new compound is a fluorescent inhibitor of rabbit muscle glycogen phosphorylase with properties of a molecular rotor. Fluorescence measurements in solutions of increasing viscosity determined that the fluorescence intensity increases with the viscosity of the medium, indicating that the new compound exhibits molecular rotor characteristics. Although the compound fluoresces negligibly in an aqueous buffer solution, in the presence of increasing amounts of rabbit muscle glycogen phosphorylase, we observed an increase in fluorescence intensity, which was attributed to the formation of an inhibitor–enzyme complex. In-vitro cellular studies were also undertaken, yielding promising preliminary results for the use of the new compound as a fluorescent probe. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Molecular Docking Studies on Synthetic Therapeutic Agents for COVID-19

by

Lucia Pintilie

,

Constantin Tanase

and

Ranjan Kumar Mohapatra

Chem. Proc. 2021, 3(1), 46; https://doi.org/10.3390/ecsoc-24-08352 - 14 Nov 2020

Viewed by 953

Abstract

Coronavirus disease (COVID-19) is an infectious disease caused by coronavirus 2 (SARS-CoV-2) which was detected for the first time in Wuhan China in December 2019. The rapid spread of this highly contagious and pathogenic virus led to the declaration of the pandemic by [...] Read more.

Coronavirus disease (COVID-19) is an infectious disease caused by coronavirus 2 (SARS-CoV-2) which was detected for the first time in Wuhan China in December 2019. The rapid spread of this highly contagious and pathogenic virus led to the declaration of the pandemic by the World Health Organization (WHO) on March 11, 2020. In these conditions, the discovery of new antiviral agents is extremely important. For the development of the anti-SARS-CoV-2 drugs, the fastest way is to find potential molecules from the marketed drugs by molecular docking studies. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Theoretical Study of the Aza˗Wittig Reaction, Me₃P=NR (R = Methyl or Phenyl) with Aldehyde Using the DFT and DFT-D Methods (Dispersion Correction)

by

Abdelghani Adda

and

Hayat Sediki

Chem. Proc. 2021, 3(1), 47; https://doi.org/10.3390/ecsoc-24-08349 - 14 Nov 2020

Cited by 1 | Viewed by 697

Abstract

: The Aza-Wittig reaction plays an important role in organic transformations and has seen considerable development in the construction of cyclic and acyclic compounds in neutral solvents in the absence of catalysts with a high yield of products. Today, the use of iminophosphoranes [...] Read more.

: The Aza-Wittig reaction plays an important role in organic transformations and has seen considerable development in the construction of cyclic and acyclic compounds in neutral solvents in the absence of catalysts with a high yield of products. Today, the use of iminophosphoranes (phosphazenes) has become a powerful tool in organic synthesis strategies directed toward the construction of nitrogenous heterocycles. These can react with carbonyl compounds, an excellent method for the construction of C=N double bonds via intermolecular and intramolecular Aza-Wittig reactions. In this study, we are interested in the theoretical study of the reaction path of the Aza˗Wittig reaction between trimethyl-iminophosphoranes (CH₃)₃P=NR, R = CH₃ or Ph) for the two-substituent methyl and phenyl with acetaldehyde, including continuum solvation. Our calculations were carried out by means of ab initio calculations using DFT (Density Function Theory) with a dispersion correction term using the Grimme method in the program Gaussian09, using the functional B3LYP-GD3BJ with a 6-31G** base. The results obtained allowed us to highlight the mechanisms of the Aza-Wittig reaction in particular after the addition of the term of dispersion correction or van der Waals correction, which provides a new description of this reaction and its chemical path. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Towards Greener Mechanosynthesis of Functional Calixarenes

by

Clara Silveiro

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Vasco D. B. Bonifácio

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José V. Prata

,

Alexandra I. Costa

and

Patrícia D. Barata

Chem. Proc. 2021, 3(1), 48; https://doi.org/10.3390/ecsoc-24-08405 - 14 Nov 2020

Viewed by 584

Abstract

The awareness of sustainability led to increasing global demand for processes that use lower energy, produce reduced waste, use fewer organic solvents, and offer improved selectivity. In this context, mechanochemistry re-emerged as a powerful green methodology. The conventional synthesis and functionalization of calixarenes, [...] Read more.

The awareness of sustainability led to increasing global demand for processes that use lower energy, produce reduced waste, use fewer organic solvents, and offer improved selectivity. In this context, mechanochemistry re-emerged as a powerful green methodology. The conventional synthesis and functionalization of calixarenes, both on the upper and lower rim, has been the subject of numerous studies but only a few were reported using a mechanochemical approach. Herein, we present new mechanically assisted key synthetic steps towards a more sustainable route to calix[4]arenes functionalized in the lower rim. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

In Silico Study of the Interaction between Casein with Tocopherols: Preliminary Evaluation of Lipophilic Substrate Inclusion on Proteic Matrix

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Chem. Proc. 2021, 3(1), 49; https://doi.org/10.3390/ecsoc-24-08345 - 14 Nov 2020

Cited by 1 | Viewed by 846

Abstract

Bovine casein is a family of milk proteins with hydrophilic and hydrophobic regions that show block distribution within the protein chain. These amphiphilic properties offer great potential as a material for use as a matrix for transporting active materials such as tocopherol. In [...] Read more.

Bovine casein is a family of milk proteins with hydrophilic and hydrophobic regions that show block distribution within the protein chain. These amphiphilic properties offer great potential as a material for use as a matrix for transporting active materials such as tocopherol. In this work, we aimed to evaluate the interaction of α1-casein, the main fraction of casein, with vitamin E by docking calculations. Docking studies were conducted using SwissDock and DockThor servers. Using specific scoring functions based on energy terms, the best protein–ligand binding models were obtained. The observed interactions between vitamin E and amino acid residues consisted of several hydrophobic interactions (e.g., with Tyr119, Ala144, Trp179, Met211, Pro212). A few hydrogen bonds were observed between the phenyl group of vitamin E and the carboxylate group of the glutamic acid residue (e.g., with Glu85, Glu148). In conclusion, the results suggest that there is a major interaction of vitamin E with random coil structure and interaction with segments formed by α-helix and β-sheet. This implies that in random coil segments there is a predominance of hydrophobic domains. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

A New Approach to 7-Amino-4-oxo-4,5-dihydro-3H-pyrano[2,3-d]pyrimidine-6-carbonitriles

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Chem. Proc. 2021, 3(1), 50; https://doi.org/10.3390/ecsoc-24-08105 - 13 Nov 2020

Cited by 1 | Viewed by 503

Abstract

S-alkyl derivatives of thiobarbituric acid easily react with arylmethylene malononitriles in the presence of base to give new 7-amino-4-oxo-4,5-dihydro-3H-pyrano[2,3-d]pyrimidine-6-carbonitriles. The structure of products and the mechanism of formation are discussed. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Preparation of Cu₄SnS₄/CuCo₂S₄ Nanoparticles Using Combustion Reaction Accelerated by Organic Driving Agents under Microwave Irradiation

by

Maede Aghaei

,

Mina Imani

and

Azadeh Tadjarodi

Chem. Proc. 2021, 3(1), 51; https://doi.org/10.3390/ecsoc-24-08354 - 14 Nov 2020

Viewed by 644

Abstract

Copper-based sulfide-rich nanomaterials have recently attracted attention in various applications due to the lack of expense, abundance, and non-toxicity of their constituent elements. As the members of this family, Cu₄SnS₄ and CuCo₂S₄ have exhibited good capability in [...] Read more.

Copper-based sulfide-rich nanomaterials have recently attracted attention in various applications due to the lack of expense, abundance, and non-toxicity of their constituent elements. As the members of this family, Cu₄SnS₄ and CuCo₂S₄ have exhibited good capability in a stable manner in solar cells, energy storage electrodes, batteries, etc. In this work, through a facile and rapid combustion reaction accelerated by microwave irradiation, Cu₄SnS₄/CuCo₂S₄ nanoparticles were prepared. Thiourea was used as a sulphur source and also organic driving agent. The features of the synthesized product were studied using FT-IR, XRD, SEM, and EDX techniques. The FT-IR and XRD results showed the formation of a multi-components structure containing orthorhombic crystalline phase of Cu₄SnS₄ alongside carrollite CuCo₂S₄ phase. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Microwave Assisted Synthesis of CoFe₂O₄ Nanoparticles by Utilizing Organic Promoters and Evaluation of Its Properties

by

Rahil Ahmadi

,

Mina Imani

and

Azadeh Tadjarodi

Chem. Proc. 2021, 3(1), 52; https://doi.org/10.3390/ecsoc-24-08351 - 14 Nov 2020

Cited by 3 | Viewed by 770

Abstract

Nano-sized spinel ferrites are highly regarded owing to their special optical, electrical, and magnetic properties. Cobalt ferrite (CoFe₂O₄) is a nominee of particular interest due to its high saturation magnetization, high coercivity, strong anisotropy, and excellent chemical stability. The [...] Read more.

Nano-sized spinel ferrites are highly regarded owing to their special optical, electrical, and magnetic properties. Cobalt ferrite (CoFe₂O₄) is a nominee of particular interest due to its high saturation magnetization, high coercivity, strong anisotropy, and excellent chemical stability. The synthesis of these materials with a pure crystalline phase is sometimes limited due to the required high temperatures for their calcination. In this work, we report a one-pot simple synthesis procedure of cobalt ferrite by the auto-combustion under microwave irradiation into a domestic microwave oven with a power of 900 W for 30 min. Glycine and ammonium nitrate were used as organic promoters and metal nitrates as precursors. The synthesized nanoparticles were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersion of X-ray spectrometry (EDX) techniques. The electrochemical properties and capability of the prepared product as a pseudocapacitive material were evaluated using cyclic voltammetry (CV) tests in details. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

s-Triazine: A Multidisciplinary and International Journey

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Beatriz G. de la Torre

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Fernando Albericio

and

Ayman Al-Faham

Chem. Proc. 2021, 3(1), 53; https://doi.org/10.3390/ecsoc-24-08502 - 20 Nov 2020

Viewed by 796

Abstract

2,4,6-Trichloro-1,3,5-triazine (TCT) offers the unique ability to undergo sequential nucleophilic substitution reactions using regular nucleophiles (first Cl replacement at 0 °C, second at RT, and third at >90 °C), making s-triazine a privileged scaffold-finding application in drug development with an extension towards the [...] Read more.

2,4,6-Trichloro-1,3,5-triazine (TCT) offers the unique ability to undergo sequential nucleophilic substitution reactions using regular nucleophiles (first Cl replacement at 0 °C, second at RT, and third at >90 °C), making s-triazine a privileged scaffold-finding application in drug development with an extension towards the development of new materials. This selective chemical property of TCT fulfills the goal of chemists to control organic structures and make them react in the required conditions for achieving each objective. In this regard, orthogonality and chemoselectivity are two modern organic chemistry concepts which have been exploited in various areas of research, ranging from supramolecular chemistry to organic/bioconjugation chemistry. We have demonstrated the fusion of these two concepts using TCT as “Orthogonal Chemoselectivity” and defined it as discrimination between reactive sites in any order. The usage of azide as one of the nucleophiles modulated the reactivity of the s-triazine core for the last Cl replacement. This allowed us to overcome the barrier of higher temperature (>90 °C) for the last Cl replacement which happened at RT, taking advantage of side chains of Cys, Tyr and Lys in a biological context. In this presentation, we revise the chemistry developed in our laboratories to manipulate the TCT core for application in our medicinal chemistry programs and in bioconjugation. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

Open AccessProceeding Paper

Synthesis of 1,2,3-Triazoles from Alkyne-Azide Cycloaddition Catalyzed by a Bio-Reduced Alkynylcopper (I) Complex

by

Josué Varela-Palma

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Jaime González

,

Gustavo Lopez-Téllez

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Marco A. García-Eleno

and

Erick Cuevas-Yañez

Chem. Proc. 2021, 3(1), 54; https://doi.org/10.3390/ecsoc-24-08384 - 14 Nov 2020

Cited by 2 | Viewed by 703

Abstract

A small library of 1,2,3-triazoles was synthesized from diverse alkynes and azides using catalytic amounts of an alkynylcopper (I) complex, which in turn was prepared from direct treatment of phenylacetylene with a Fehling reagent in the presence of glucose as a reducing agent. [...] Read more.

A small library of 1,2,3-triazoles was synthesized from diverse alkynes and azides using catalytic amounts of an alkynylcopper (I) complex, which in turn was prepared from direct treatment of phenylacetylene with a Fehling reagent in the presence of glucose as a reducing agent. The results suggest that copper-catalyzed azide alkyne cycloaddition (CuAAC) reactions require only 0.5 mg/mmol copper (I) phenylacetylide without any further additives. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Synthesis and Leishmanicidal Activity of Molecular Hybrids 1,2,3-Triazole-Chalcones

by

Sofía Vanessa Rodríguez-Gutiérrez

,

Olalla Barreiro-Costa

,

Christian David Alcívar León

and

Jorge Heredia-Moya

Chem. Proc. 2021, 3(1), 55; https://doi.org/10.3390/ecsoc-24-08356 - 14 Nov 2020

Cited by 3 | Viewed by 1198

Abstract

Leishmaniasis is a largely neglected infection caused by Leishmania spp. parasites. The first-line treatment, antimoniate meglumine, has a large number of adverse effects, high cost and is prone to resistance development, hence the necessity of new alternatives. We report the synthesis of (2E)-1-[1-(4-methoxyphenyl)-5-methyl-1H-1,2,3-triazol-4-yl]-3-arylprop-2-en-1-one [...] Read more.

Leishmaniasis is a largely neglected infection caused by Leishmania spp. parasites. The first-line treatment, antimoniate meglumine, has a large number of adverse effects, high cost and is prone to resistance development, hence the necessity of new alternatives. We report the synthesis of (2E)-1-[1-(4-methoxyphenyl)-5-methyl-1H-1,2,3-triazol-4-yl]-3-arylprop-2-en-1-one derivatives and the in vitro evaluation of their leishmanicidal activities. A series of 16 compounds were synthesized in three steps starting from p-anisidine with moderate to good yields and their biological activities were evaluated in vitro against Leishmania mexicana promastigotes and RAW 264.7 cells. The synthesis of 1,2,3-triazol and chalcone moieties were made using a cycloaddition with acetylacetone followed by a Claisen-Schmidt condensation using different substituted benzaldehydes. Nine compounds were active against L. mexicana with IC₅₀ between 1.0 and 29.2 µM. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Density Functional Theory (DFT) and Thermodynamics Calculations of Amino Acids with Polar Uncharged Side Chains

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Chem. Proc. 2021, 3(1), 56; https://doi.org/10.3390/ecsoc-24-08420 - 14 Nov 2020

Cited by 1 | Viewed by 911

Abstract

The goal of the present work was to evaluate the chemical reactivity of amino acids with polar uncharged side chains (serine, threonine, asparagine and glutamine) using density functional theory (DFT) and thermodynamics modeling by calculating a series of molecular descriptors and properties of [...] Read more.

The goal of the present work was to evaluate the chemical reactivity of amino acids with polar uncharged side chains (serine, threonine, asparagine and glutamine) using density functional theory (DFT) and thermodynamics modeling by calculating a series of molecular descriptors and properties of their optimized geometries. The predictive calculations were achieved with Spartan software from Wavefunction, Inc. Irvine, CA, USA, hybrid algorithm B3LYP (Becke’s three-term functional; Lee, Yang, Parr exchange hybrid) and polarization basis set 6-31G(d,p) for equilibrium geometry at ground state in vacuum and in water, after energy minimization and geometry optimization. Thermodynamic properties (zero-point energy, enthalpy, constant volume heat capacity, entropy and Gibbs energy) for these derivatives were calculated and related to electrochemical ligand behavior. Reduction and oxidation potentials were correlated to their calculated energy levels for molecular orbitals. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

Open AccessProceeding Paper

Cycloaddition of Thiourea- and Guanidine-Substituted Furans to Dienophiles: A Comparison of the Environmentally-Friendly Methods

by

Luka Barešić

,

Davor Margetić

and

Zoran Glasovac

Chem. Proc. 2021, 3(1), 57; https://doi.org/10.3390/ecsoc-24-08380 - 14 Nov 2020

Cited by 2 | Viewed by 652

Abstract

The cycloaddition strategy was employed in order to obtain a 7-oxanorbornene framework substituted with a guanidine moiety or its precursor functional groups: protected amine or thiourea. In order to optimize the conditions for the cycloaddition, several environmentally-friendly methods—microwave assisted organic synthesis, high pressure [...] Read more.

The cycloaddition strategy was employed in order to obtain a 7-oxanorbornene framework substituted with a guanidine moiety or its precursor functional groups: protected amine or thiourea. In order to optimize the conditions for the cycloaddition, several environmentally-friendly methods—microwave assisted organic synthesis, high pressure synthesis, high speed vibrational milling, and ultrasound assisted synthesis—were employed. The outcomes of the cycloaddition reactions were interpreted in terms of endo/exo selectivity, the conversion of the reactants to the product, and the isolated yields. In general, our results indicated the HP and HSVM approaches as the methods of choice to give good yields and conversions. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Study of Organic Radicals Generated upon Naphthoquinone-Hydantoins Reactions in Basic Aqueous Solution

by

Enrique Flores

,

Ernesto Rivera-Avalos

,

Braulio Rodríguez-Molina

,

Carlos Frontana

,

Lluvia López

and

Denisse de Loera

Chem. Proc. 2021, 3(1), 58; https://doi.org/10.3390/ecsoc-24-08415 - 14 Nov 2020

Viewed by 735

Abstract

In this work, the synthesis of thiohydantoins from l-amino acids and isothiocyanates was studied, using a high purity method based on the Edman cycle. This process, expected to occur through the Michael addition to a series of 1,4-naphthoquinone derivatives did not lead to [...] Read more.

In this work, the synthesis of thiohydantoins from l-amino acids and isothiocyanates was studied, using a high purity method based on the Edman cycle. This process, expected to occur through the Michael addition to a series of 1,4-naphthoquinone derivatives did not lead to the expected final product, rather leading to a colored mixture of compounds, where EPR spectra showed that some of them presented unpaired electrons, indicating that an electron transfer pathway was also involved in the reaction mixture. Detected organic radicals proved to be stable albeit with the use of different experimental conditions. Voltammetric results indicated that the reactions led to the formation of electroactive species, probably derived by homogeneous electron transfer between the reactive quinone moieties and the oxidizable urea functions within the hydantoin species. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

A One-Pot Synthesis of Fluoro α-Acylamino Amide-Xanthates via an IMCR-Post Transformation Strategy

by

Manuel A. Rentería-Gómez

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Tannya R. Ibarra-Rivera

and

Chem. Proc. 2021, 3(1), 59; https://doi.org/10.3390/ecsoc-24-08421 - 14 Nov 2020

Viewed by 693

Abstract

A series of six novel amide-xanthate products containing several fluorine atoms were prepared in moderate to good yields (40–92%) via an isocyanide-based multicomponent reaction (IMCR) of 5-CR by Ugi-4CR followed by an S_N2 sequence in a one-pot manner. The design of [...] Read more.

A series of six novel amide-xanthate products containing several fluorine atoms were prepared in moderate to good yields (40–92%) via an isocyanide-based multicomponent reaction (IMCR) of 5-CR by Ugi-4CR followed by an S_N2 sequence in a one-pot manner. The design of molecules with fluorine atoms is of interest in medicinal chemistry and a research line of our interest. The role of fluorine atoms in biological properties is well documented, improving bioavailability, lipophilicity, and metabolic resistance in bioactive molecules. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Facile Microwave-Assisted Preparation of Hetero-Structured CuCo₂S₄/CuCo₂O₄ Nanoparticles Using Organic Agent of Thiourea

by

Mahdi Bahmani

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Mina Imani

and

Azadeh Tadjarodi

Chem. Proc. 2021, 3(1), 60; https://doi.org/10.3390/ecsoc-24-08347 - 14 Nov 2020

Viewed by 570

Abstract

Ultra-fast one-put microwave assisted strategy was introduced for the synthesis of hetero-structured CuCo₂S₄/CuCo₂O₄ nanoparticles into a domestic microwave oven with the power of 900 W for 20 min. Thiourea as an organic agent was used as [...] Read more.

Ultra-fast one-put microwave assisted strategy was introduced for the synthesis of hetero-structured CuCo₂S₄/CuCo₂O₄ nanoparticles into a domestic microwave oven with the power of 900 W for 20 min. Thiourea as an organic agent was used as a sulfur source and driving agent to lead the solvent free combustion reaction to obtain this earth-abundant and low-cost mixed chalcogenide/oxide product. The structural and morphological specifications were studied in details using powder x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT−IR), scanning electron microscopy (SEM), and energy dispersion of x-ray spectrometry (EDX). The employed strategy relatively clarifies a new facile, rapid, and eco-friendly route to produce heterostructured nanocomposites for different functional purposes. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Synthesis of Triphenylamine-Imidazo[1,2-a]pyridine via Groebke–Blackburn–Bienaymé Reaction

by

Manuel A. Rentería Gómez

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Mahanandaiah Kurva

and

Chem. Proc. 2021, 3(1), 61; https://doi.org/10.3390/ecsoc-24-08422 - 14 Nov 2020

Cited by 2 | Viewed by 716

Abstract

A series of triphenylamine-imidazo[1,2-a]pyridine were synthesized in moderate yields (57–67%) by Groebke–Blackburn–Bienaymé reaction (GBBR) under catalyst and solvent green conditions. The molecules synthesized containing triphenylamine and imidazo[1,2-a]pyridines cores which are considered a privileged cores exhibited fluorescence and medicinal properties. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Synthesis of Amino Alcohols from Eugenol and Their Insecticidal Activity against Sf9 Cell Line

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Maria José G. Fernandes

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and

Chem. Proc. 2021, 3(1), 62; https://doi.org/10.3390/ecsoc-24-08337 - 14 Nov 2020

Cited by 2 | Viewed by 629

Abstract

Eugenol is a major constituent of clove essential oil with interesting biological activity, namely antimicrobial and antioxidant. Structural changes of eugenol are a useful strategy in order to improve biological activity and at the same time obtain new analogues with reduced side effects. [...] Read more.

Eugenol is a major constituent of clove essential oil with interesting biological activity, namely antimicrobial and antioxidant. Structural changes of eugenol are a useful strategy in order to improve biological activity and at the same time obtain new analogues with reduced side effects. In this work, a series of amine nucleophiles were reacted with eugenol epoxide so as to obtain the corresponding amino alcohols, considering their potential as biopesticides. These eugenol amino alcohols were evaluated against insect cells, specifically the Sf9 cell line. Full article

(This article belongs to the Proceedings of The 24th International Electronic Conference on Synthetic Organic Chemistry)

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Open AccessProceeding Paper

Evaluation of Fluorescent Staining Capacity of Two New Nile Blue Analogues

by

João C. C. Ferreira

,

Rui P. C. L. Sousa

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Maria João M. F. Sousa

and