Letters in Organic Chemistry最新文献

{"title":"Can Glycerol Carbonate be Synthesized Without a Catalyst?","authors":"Sanjib Kumar Karmee","doi":"10.2174/0115701786280075231211094705","DOIUrl":"https://doi.org/10.2174/0115701786280075231211094705","url":null,"abstract":": Biodiesel and oleo-chemical industries have been producing huge quantities of glycerol as a by-product. Value-added products can be synthesized from glycerol through different chemical and enzymatic reactions, such as oxidation, carbonylation, reforming, acetalyzation, etherification, dehydration, hydrogenolysis, hydrolysis, esterification, and transesterification. Glycerol is a low-cost polyol that can be converted into glycerol carbonate, which has potential applications in polymer and biobased non-isocyanate polyurethanes industries (Bio-NIPUs). The present contribution is the first of its kind to report on the synthesis of glycerol carbonate via catalyst and solvent-free transesterification of glycerol with dimethyl carbonate under conventional as well as microwave heating. Additionally, a comparative study of conventional and microwave-assisted transesterification was performed. Under conventional heating, 78% glycerol carbonate is obtained at 120 o C in 36 hours, whereas, using microwaves, 92% of glycerol carbonate can be achieved in 30 minutes. Presently, biomass-based heterogeneous materials are used in catalysis due to their importance within the context of sustainability. In line with this, in this work, a series of green catalysts, namely, molecular sieves (MS, 4Å), HβZeolite, Montmorillonite K-10 clay, activated carbon prepared from the shell of groundnut (Arachis hypogaea), and biochar from sawdust pyrolysis were successfully employed. Glycerol carbonate was thoroughly characterized by 1 H and 13C NMR, FT-IR and MS. The method described here is facile and green since the utilization of bioresource (glycerol) for the production of glycerol carbonate is performed under microwave.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"41 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139461641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"1,3,4-Thiadiazole: A Versatile Scaffold for Drug Discovery","authors":"Ravi K. Mittal, Raghav Mishra, Vikram Sharma, Isha Mishra","doi":"10.2174/0115701786274678231124101033","DOIUrl":"https://doi.org/10.2174/0115701786274678231124101033","url":null,"abstract":":: 1,3,4-Thiadiazole has garnered considerable attention in the scientific community due to its captivating molecular structure and ability to serve as a foundation for creating novel pharmaceutical compounds. Numerous medications feature the 1,3,4-thiadiazole ring in their chemical structure, highlighting its relevance and efficacy in pharmaceutical research and development. The key objective of this comprehensive review is to provide an understandable overview of the chemistry and diverse pharmacological activities associated with 1,3,4-thiadiazole compounds. The manuscript was compiled by conducting a thorough literature review, which included an in-depth analysis of globally esteemed scientific research databases. The remarkable chemical characteristics and diverse pharmacological impacts of 1,3,4-Thiadiazole highlight its significant potential as a structural scaffold for the development of novel therapeutic substances. Based on the information available on synthetic molecules that incorporate the 1,3,4-thiadiazole framework and their wide range of uses, it is reasonable to expect significant advancements in the near future and the possibility of employing these compounds in different domains.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"22 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139055868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Review on Diverse Biological Activity of Heterocyclic Nucleus Pyrazine and its Derivatives: A Key for the Researchers","authors":"Shilpi Pathak, Neetu Agrawal, Sonam Gaur","doi":"10.2174/0115701786273932230927062616","DOIUrl":"https://doi.org/10.2174/0115701786273932230927062616","url":null,"abstract":": Pyrazine belongs to the 1, 4-diazines family, which is a significant class of heterocyclic compounds. Various pyrazine derivatives have been produced and successfully confirmed as medicines with various pharmacological activities like anti-inflammatory, antitubercular, anticancer, antibacterial, and neurological activity, with some of them becoming clinically utilized pharmaceuticals globally. This review includes a survey on pyrazine derivatives possessing different pharmacological activities. The class of pyrazine-based potential medications has grown rapidly in terms of both the absolute quantity of studied compounds and the range of various biological activities. Additionally, there is a lot of potential for this scaffold, which medicinal chemists ought to investigate for the creation of novel potential drug candidates.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"17 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139051362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phytochemical Evaluation of Selected Ayurvedic Formulations and Evaluate their Antioxidant Activity","authors":"Awadhesh Kumar, Akash Ved, Karuna S. shukla, Amit Kumar Nigam","doi":"10.2174/0115701786226175231023112257","DOIUrl":"https://doi.org/10.2174/0115701786226175231023112257","url":null,"abstract":": The Ayurvedic formulations' evaluation is very wide and deep. The project's goal was to evaluate the phytochemistry and antioxidant activity of Ayurvedic formulations used to treat digestive disorders. Herbal formulations are typically available as single or mixed formulations of multiple plant constituents, and it is critical to quantify the number of markers present in such formulations to ensure the product's high quality. The extract of formulations (Ajmodadi churna, Avipattikar churna, and Sanjivani vati) was subjected to physicochemical screening, phytochemical screening, HPTLC, and antioxidant activity was observed in the current study. Three ayurvedic formulations (Sanjivini vati, Ajmodadi Churna, and Avipattikar Churna) were studied physicochemically in this study. The extraction process determined the total phenolic and flavonoid content. The antioxidant capacity of the selected formulation was calculated by three methods; total antioxidant capacity, ferric-reducing power, and DPPH scavenging activity. The active constituent was isolated using the HPTLC method. This study shows that the formulations Ajmodai churna, Avipattikar churna, and Sanjivani vati are important sources of antioxidant compounds. The active constituent was isolated using the HPTLC method. The HPTLC technique showed the presence of phenolics and terpenoids that are responsible for antioxidant activity. Phenolics and Terpenoids, due to their antioxidant activity, are used as an important source for digestive disorders.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"51 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138516057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of Structural Elucidation, Degradation Kinetics and Antimicrobial Analysis of Copper (II) Sesame-Soap Complexes with Urea and Thiourea Ligand in Non-aqueous Solvents","authors":"Asha Meena","doi":"10.2174/0115701786260899231023091359","DOIUrl":"https://doi.org/10.2174/0115701786260899231023091359","url":null,"abstract":": Surfactants have great importance in biological and drug industries and the complexes of metallic soaps with various ligands are used in approximately every region of national economy. Therefore, our keen interest to study of degradation kinetics and biological importance of Cu (II) surfactants in non-aqueous and non-polar solvent benzene. Present research work has been initiated with synthesis, systematic study of structural elucidation, thermal degradation, kinetics and biocidal activities of copper (II) sesame-soap complexes with macrocyclic nitrogen and sulphur containing donar ligands like urea and thiourea. The thermal degradation of copper (II) sesame-soap complexes were carried out for analysis of degradation kinetics and estimation of kinetic and thermodynamic parameters using different methods at heating rate 10 o C min-1 . Copper (II) sesame-soap complexes of such ligands have also been analysed against Staphylococus aureus. This research work consolidates the synthesis of copper (II) sesame soap-urea and thiourea complexes by conventional methods and the structure of these complexes were assigned according to elemental analysis and molecular weight determinations. IR, NMR and ESR spectral studies have also been done to understand structural aspects. The anti-microbial activities of copper (II) sesame-soap urea and thiourea complexes have been evaluated by testing against Staphylococus aureus. The present research work includes information of thermal analysis using TGA technique to find out their kinetic and thermodynamic parameters by using diverse equations such as Coats-Redfern equation, Horowitz-Metzger equation, Broido equation, Piloyan–Novikova equation. Moreover, the results obtained from anti-microbial screening have been used to analyze the anti-microbial activities of copper (II) sesame-soap urea and thiourea complexes against gram-positive bacteria Staphylococus aureus. These results show that complexes of copper ion co-ordinated with different nitrogen, oxygen and sulphur containing ligands, are very important in the field of pharmaceutical chemistry due to its significant role in the inhibition activity. The study of these complexes concludes that the synthesized complexes were found to possess appreciable bactericidal properties at different concentrations because chelation increases the anti-microbial potency.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"18 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138516048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel Study on Antioxidant activity and Catalytic Reduction of Methylene Blue using ZnO nanoparticles synthesized via the middle part of Walnut shell (Juglans regia) Extract","authors":"Pouya Jafari, Mohammad Hadi Meshkatalsadat, Behjat Pouramiri","doi":"10.2174/1570178620666230914104742","DOIUrl":"https://doi.org/10.2174/1570178620666230914104742","url":null,"abstract":"Background: The synthesized ZnO nanoparticles were characterized using UV-Vis spectroscopy, SEM, XRD, FTIR, and TEM analysis. The catalytic activity of the prepared green catalyst ZnO nanoparticles was also investigated in the dye methylene blue (MB) decomposition. The catalytic decomposition reaction was completed within 20 minutes, demonstrating the excellent catalytic properties of ZnO nanoparticles in reducing MB. Aim: This research aims to describe the green synthesis of ZnO nanoparticles using an extract of the middle part of a walnut shell (Juglans regia). Method: The antioxidant activities (radical capture capacity) of the synthesized ZnO nanoparticles were evaluated by the 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) assay at different ZnO nanoparticle concentrations, and the radical capture activity was achieved at IC50 = 146.32 μg / mL. Result: The radical capture activity was achieved at IC50 = 146.32 μg Conclusion: The biosynthesis of ZnO nanoparticles was caused by hydroxide precipitation at room temperature after calcination at 450°C.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136017613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"N-acetylation of aromatic amines by one-pot route","authors":"Zhongqi Guo, Keyume Ablajan, Wenxu Fan","doi":"10.2174/0115701786266810231005103940","DOIUrl":"https://doi.org/10.2174/0115701786266810231005103940","url":null,"abstract":"aims: To achieve acylation of aryl amine via one-pot route. background: Amides are one of the most common and important structural motifs. Several different strategies have been employed to produce acetamide. However, some of these methods require bases, prolonged reaction times, metal catalysis, or toxic reagents. To overcome these limitations, a new method for the synthesis of N-acetanilide is needed. objective: We have to develope an economical, efficient, and metal-free strategy for synthesizing N-acetanilide by reacting aniline with CH3CN and DMSO. method: The amidation was performed in presence of H2O and K2S2O8 in a mixed solvent (CH3CN:DMSO). result: A series of amide compounds using K2S2O8 as the oxidant and amines as substrates in acetonitrile and water without any transition metals is reported. conclusion: The method uses simple, easily available materials in a straightforward protocol that allows the ease of isolating the products other: No other contents.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"34 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134910210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Convenient Synthesis of Bis-(dihydro)caffeoylspermidines","authors":"Lili He, Jian Sun, Pengjuan Zhou, Jingwen Ji, Lijuan Zhai, Dong Tang, Jinbo Ji, Haikang Yang, Zafar Iqbal, Zhixiang Yang","doi":"10.2174/0115701786265776230929180406","DOIUrl":"https://doi.org/10.2174/0115701786265776230929180406","url":null,"abstract":"Abstract: Caffeoyl spermidines are valuable alkaloids naturally existing in many plant species. These alkaloids are characterized as pharmacologically important ingredients of many plant extracts used in traditional medicines. Bis-caffeoylspermidine and bis-dihydrocaffeoylspermidine exhibit antioxidant, anti-inflammatory, and enzyme inhibition properties that make them valuable natural sources of safer therapeutic agents. However, the limited availability of these compounds in nature derives the attention of synthetic chemists. Therefore, we synthesized bis-caffeoylspermidine and bisdihydrocaffeoylspermidine using cheaper and commercially available starting materials in 97% and 86% overall yields, respectively. The synthetic scheme can be upgraded to the commercial-scale synthesis of these compounds.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"23 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135322813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis, Bioactivity Evaluation, and Molecular Docking Study of Tranilast Analogs as Anticancer Agents","authors":"Phuong-Thuy T. Phan, Tuan-Anh N. Pham, Ngoc Phuong Nguyen, Van-Anh Tran Nguyen, Tuyet Hong Nguyen","doi":"10.2174/0115701786268073230926160649","DOIUrl":"https://doi.org/10.2174/0115701786268073230926160649","url":null,"abstract":"Abstract: Developing new agents with higher therapeutic potential and less toxicity to overcome the limitations of chemotherapy in cancer treatment has been identified as an urgent need and priority. Recent studies have shown promising anticancer activities of tranilast when used alone or in combination with other chemotherapeutic agents. This research aims to synthesize tranilast analogs, evaluate in vitro anticancer activity, and dock into the TGFβ1 target to find stronger anticancer agents. Tranilast (5a) and analogs (5b–f) were synthesized from anthranilic acid derivatives, Meldrum’s acid, and benzaldehydes based on the Knoevenagel-Doebner reaction. The compounds were evaluated for in vitro cytotoxicity activity by MTT assay and docked into the TGFβ1 target using AutoDockTools–1.5.6. Tranilast (5a) and seven analogs (5b–h) were successfully synthesized and analyzed for their structures. Four analogs (5b–d, 5f) possessed stronger effects on both HepG2 and MCF-7 cell lines with proliferation inhibitions at concentrations of 100 µg/mL in the range of 41 to 95% compared to tranilast (16.95% and 22.64%). Compound 5f exhibited the most potent analog with IC50 = 27.57 µg/mL (HepG2) and 16.67 µg/mL (MCF-7) compared to tranilast (IC50 > 100 µg/mL) and had good binding affinity on TGFβ1 target (docking score ˗7.35 Kcal/mol). Four of seven tranilast analogs possessed stronger cytotoxicity activity on both HepG2 and MCF-7 cell lines compared to that of the parent compound, tranilast. Notably, compound 5f displayed the most potent activity and good binding affinity on the TGFβ1 target, indicating the potential for further study as an anticancer agent.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135620248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isatin Derivatives: A Frontier in Antimicrobial Agents","authors":"Shareef Shaikh, Manish Chaudhary, Charanjit Kaur, Rajesh Kumar, Gurvinder Singh","doi":"10.2174/0115701786268852230921113433","DOIUrl":"https://doi.org/10.2174/0115701786268852230921113433","url":null,"abstract":"Abstract: Microbial infection is one of the major concerns for human health in the modern era. Condition is further worsening due to the development of resistance by the microbe against the available drugs. This problem can be overcome by synthesizing novel antimicrobial agents. Isatin is a promising moiety possessing antimicrobial activity. A number of isatin derivatives are present in the market for the treatment of microbial infection. In this review, we have tried to summarize isatin derivatives as antimicrobials, including numerous potent isatin analogs. The reported literature related to the development and application of isatin derivatives have been collected from electronic data bases like Science Direct, Google Scholar, and PubMed by using key words like “design, synthesis and evaluation”, “isatin derivatives,” and “indoldione analogues” and related combinations. It was identified that isatin derivatives play an essential role in drug discovery and development. In recent years, isatin and its derivatives have shown promising antibacterial and antiviral properties. This review aims to provide an overview of the current research on isatin potential applications. Studies have shown that isatin derivatives can effectively fight against various types of microorganisms, such as gram-negative and gram-positive bacteria. They also exhibit lower toxicity and better efficacy than standard antimicrobial agents. Moreover, isatin-based products have the potential to address the rising issue of antimicrobial resistance. The current work attempts to review such innovations, which may lead to the creation of novel therapeutic agents. More research is required to confirm their safety and effectiveness in clinical practice.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136358653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}