Letters in Organic Chemistry最新文献

{"title":"Antioxidant Activities and Phenolic Composition of Sarcococca saligna Leaves","authors":"Syed Mubashar Sabir, Shabnam Shahida, Alam Zeb, Syed Rizwan Abbas, Muhammad Usman Hameed, Abdallah Shanableh, Muhammad Imran Khan, Djamel Ghernaout, Ramzi Hadj Lajimi, Sarra Elgharbi, Malek Besbes, Noureddine Elboughdiri","doi":"10.2174/0115701786293349240229074809","DOIUrl":"https://doi.org/10.2174/0115701786293349240229074809","url":null,"abstract":": Sarcococca saligna (D. DON) Muel is a vital plant with several steroidal alkaloids and is effective against syphilis, liver diseases, gastrointestinal tract disease, infections, and inflammation. The present study aimed to investigate the in vitro antioxidant activities and phenolic profile of S. saligna. High-performance liquid chromatography (HPLC) analysis has shown the presence of twelve phenolics namely kaempferol-3-O-glucoside, proanthocyanidin B1, quercetin-3-malonylglucoside- 7-glucoside, kaempferol-3-O-sophorotioside, Isorhamnetin-3-O-glucoside-7-Orhamnoside, kaempferolhexoside, 4-O-Caffeoyl-5-O-p-coumaroylquinic acid, 3,4-Di-O-caffeoyl-5- O-feruloylquinic acid, 3,4-Di-O-feruloyl-5-O-caffeoylquinic acid, flavogalloyl-HHDP-gluconic acid (lagerstannin B), 3,4-di-O-caffeoylquinic acid and kaempferol-3-(caffeoyldiglucoside)-7-glucoside. The hot water extract showed the highest anti-lipid peroxidative activities. The IC50 value for 2,2- diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity was 71.5 ± 2.1 μg/mL. The extract could chelate the iron and possess reducing activities on phosphomolybenum assay. It is concluded that extracts of S. saligna are rich in antioxidants and contain essential phytochemicals. objective: The present study was aimed to investigate thein vitro antioxidant activities and phenolic profile of S. saligna. HPLC analysis has shown the presence of twelve phenolics namely kaempferol-3-O-glucoside, proanthocyanidin B1, quercetin-3-malonyl-glucoside-7-glucoside, kaempferol-3-O-sophorotioside,Isorhamnetin-3-O glucoside-7-O-rhamnoside,kaempferolhexoside, 4-O-Caffeoyl-5-O-p-coumaroylquinic acid, 3,4-Di-O-caffeoyl-5-O-feruloylquinic acid, 3,4-Di-O-feruloyl-5-O-caffeoylquinic acid, flavogalloyl-HHDP-gluconic acid (lagerstannin B), 3,4-di-O-caffeoylquinic acid and kaempferol-3-(caffeoyldiglucoside)-7-glucoside. method: The chemical used were 1,10-phenathroline, Thibarbituric acid, TRIS-HCl, amominium molybdate, Iron, sodium nitroprusside. HPLC standards were purchased from Sigma-Aldrich. All the reagents were of analytical grade. Double beam spectrophotometer was used for UV-VIS spectrophotometery. The HPLC system used was Agilent 1260 Infinity HPLC system which consists of quaternary pump, degasser, auto-sampler and diode array detector (DAD). conclusion: The results have shown that S. saligna antioxidant rich extract can be effectively utilized in food and pharmaceutical industries with additional income. However, more detailed understanding of utilization of extract against degenerative diseases is required. There is also need to find out the safety and bioavailability of the plant extract for its use as nutraceutical and as a plant products.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"28 2 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140169727","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":"Polydopamine-Modified Magnetic Nanoparticles (Fe3O4@PDA) for the Copper-Catalyzed Ipso-Hydroxylation of Arylboronic Acids and Subsequent O-Benzylation in Aqueous Media","authors":"Kwang-Beom Lee, Ueon Sang Shin, Seung-Hoi Kim","doi":"10.2174/0115701786294756240305063556","DOIUrl":"https://doi.org/10.2174/0115701786294756240305063556","url":null,"abstract":": A novel advancement has emerged in the realm of catalysis with the development of an innovative method for the ipso-hydroxylation of arylboronic acids. This approach harnessed the power of bio-compatible polydopamine-coated magnetite support (Fe3O4@PDA) in conjunction with a copper salt, forming a heterogeneous catalytic environment. The resulting catalytic system facilitated oxidative hydroxylation under mild aerobic conditions at room temperature in aqueous conditions. This environmentally friendly process allowed for the seamless conversion of diverse arylboronic acids featuring varying electron-withdrawing or electron-donating groups into the corresponding phenols, achieving remarkably high yields. Notably, the versatility of the catalytic system extended to a one-pot tandem O-benzylation of the resultant phenolic intermediates. The additional dimension of the process underscores its efficiency, offering a streamlined route to synthesizing benzyl phenyl ethers with a commendable level of success. The significance of the present catalytic methodology lies not only in its efficacy but also in its eco-friendly attributes, showcasing the potential for sustainable and efficient transformations in organic synthesis.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"24 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140154603","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":"Effective Synthesis of N-Alkyl-3-(Indol-3-yl)Pyrazoles from Ag2CO3-Catalyzed Regioselective Aza-Michael Addition of 5-(Indol-3-yl)-1HPyrazoles","authors":"Xue Zhang, Dashuang Luo, Xuemin Niu, Jian Mo, Haifeng Yu, Xiaobo Zhao","doi":"10.2174/0115701786295074240305095904","DOIUrl":"https://doi.org/10.2174/0115701786295074240305095904","url":null,"abstract":": In this study, the synthesis of N-alkyl-3-(indol-3-yl)pyrazoles was carried out from Ag2CO3 catalyzed regioselective aza-Michael addition of 5-(indol-3-yl)-1H-pyrazoles to a, bunsaturated carbonyl compounds. In the presence of 10 mol% of Ag2CO3, the reaction smoothly occurred in dichloroethane (DCE) at 120oC to preferentially afford a series of N-alkyl-3-(indol-3- yl)pyrazoles in high yields with good regioselectivity. It was found that 1-methyl-3-(3-methyl-1Hpyrazol- 5-yl)-2-phenyl-1H-indole, 1-benzyl-3-(3-methyl-1H-pyrazol-5-yl)-1H-indole, a, b-unsaturated ketone, and a, b-unsaturated amide exclusively gave 3-(pyrazol-3-yl)indoles in good yields. This reaction features high regioselectivity, mild reaction conditions, good substrate scope and yields, and a commercially available catalyst. Meanwhile, the reaction was also proven to be quite practical by the gram-scale synthesis of N-alkyl-3-(indol-3-yl)pyrazoles in excellent yields with good regioselectivity.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"90 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140115547","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":"Identification and Synthesis of Oxidative-Degradation and Starting Materials-Attributed Impurities in Lisdexamfetamine Dimesylate","authors":"Suryabhan B. Chaugule, Pradip L. Gole, Siddhesh Haldankar, DVP Kishore, Nilesh L. Bonde, Sandeep A. Kotharkar","doi":"10.2174/0115701786284263240219080226","DOIUrl":"https://doi.org/10.2174/0115701786284263240219080226","url":null,"abstract":": Impurities are an integral part of drug substances, even though they have not been studied in the pharmacological evaluation of the Benefit-Risk (BR) profiles. Hence, understanding their origin and controlling them have prime importance during drug substance development. The structures of some of the impurities in lisdexamfetamine dimesylate, a central nervous system stimulant drug, have been confirmed based on literature and analytical data. The study has been undertaken to evaluate impurities arising from oxidative degradation and impurities due to material attributes. All the listed impurities have been identified, synthesized, and characterized by spectral tools. We have, herein, reported the synthesis of two oxidative degradant impurities, 2-hydroxylisdexamfetamine dimesylate and 4-hydroxylisdexafetamine dimesylate. In addition, chiral isomeric impurities of lisdexamfetamine dimesylate as (S,R), (R,S) and (R,R)-lisdexamfetamine dimesylate have also been reported. These impurities have been identified and synthesized, and a control strategy for mitigating risk in lisdexamfetamine dimesylate is provided.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"44 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140044843","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":"[EMIM] [OAc]: An Efficient Ionic Liquid Medium for the Synthesis of New 4-(furan/pyrrole/thiophene-2-yl)-3, 4-dihydro-1H-chromeno [4,3- d]pyrimidine-2,5-diones and Molecular Docking Studies","authors":"Siva Prakash Pullagura, Arunkumar Thiriveedhi, Venkateswara Rao Battula, Raghunadh Akula, A. Sajeli Begum, Lakshmi Soukya P.S.","doi":"10.2174/0115701786289993240215104621","DOIUrl":"https://doi.org/10.2174/0115701786289993240215104621","url":null,"abstract":": An efficient synthesis of Chromeno[b]pyrimidine derivatives 4 has been achieved by treating 4-hydroxy-2H-chromen-2-one 1, furan-2-carbaldehyde / 1H-pyrrole-2-carbaldehyde/ thiophene-2- carbaldehyde 2, and urea/thiourea 3 at 65-70 °C for 90-120 min using 1-Ethyl-3-methylimidazolium acetate as ionic liquid and medium with good yields 86-90%. This synthetic method has numerous advantages, including high yields, a simple protocol, environmental friendliness, brief reaction times, and mild reaction conditions. Using a catalytically active ionic liquid as the medium eliminates the need for a catalyst and a solvent. In this study, the docking score of the synthesized compounds was found to be between -8 to -9 kcal/mol similar to the co-crystal. Additionally, the compounds maintained their amino acid interactions with Tyr 281 (coagulation protein; 6WV3) and Thr 179 (tubulin polymerization protein; 5LYJ.pdb).","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"6 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140020158","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":"Cholesterol-Based B-Ring 2H-Pyran: Synthesis and Reaction Mechanism by Using Density Functional Theoretical Study","authors":"Priyanka -, Himanshi Kumar, Kamlesh Sharma","doi":"10.2174/0115701786287116240222045947","DOIUrl":"https://doi.org/10.2174/0115701786287116240222045947","url":null,"abstract":": The steroidal B-ring 2H-pyran 2 is synthesized by reacting steroidal B-ring α,β- unsaturated ketone 1 and 2-cyano-N-methylacetamide by refluxing for 18 h in methanol in the presence of a catalyst, i.e., chitosan. The product is obtained with a yield of 67%. The structure of the final product 2 is confirmed by utilizing IR, Mass, 13C and 1H NMR spectra. The reaction mechanism of the steroidal pyran ring formation is explored in this paper. The reaction pathway is described by using FMO analysis and relative energies of starting material, intermediate, and transition states, calculated by using the theoretical method, i.e., DFT with B3LYP/6-31G(d). It is found that two intermediates are formed throughout the reaction, which undergo a respective transition state (TS1 and TS2). The energy barrier of each step of the reaction is also calculated. It is also concluded that the reaction is endothermic. The green synthetic method reported in this study would be very useful for the synthetic and medicinal chemists involved in the synthesis of biologically important pyran ring-containing heterocyclic compounds.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"109 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140018664","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":"Selective Hydrogenation Reaction: Utilizing a Microreactor for Continuous Flow Synthesis of Nickel Nanoparticles","authors":"Vivek Srivastava","doi":"10.2174/0115701786268828240119105533","DOIUrl":"https://doi.org/10.2174/0115701786268828240119105533","url":null,"abstract":"Introduction:: In this investigation, we employed a continuous flow reactor to synthesize nickel (Ni) nanoparticles exhibiting uniform size distribution and excellent stability. Our focus centered on exploring the impact of reactant dilution and flow rate on the synthesis process. Result:: It was observed that the optimization of these parameters played a pivotal role in obtaining small-sized Ni nanoparticles. Specifically, we achieved successful synthesis using a solution of 0.00025 M NiCl2·6H2O and 0.002 M NaBH4, with a flow rate of 25 mL/h. The resulting Ni nanoparticles were effectively coated with the CTAB surfactant, as confirmed through thorough analysis using TEM and PSD techniques. Additionally, the interaction between the surfactant and nanoparticles was verified via FTIR analysis. We subjected them to high-pressure alkene hydrogenation to assess the catalytic activity of the synthesized Ni nanoparticles. Method:: Encouragingly, the Ni nanoparticles exhibited excellent performance, producing hydrogenated products with high yields. Moreover, we capitalized on Ni nanoparticles' catalytic effect for synthesizing two natural compounds, brittonin A and dehydrobrittonin A. Remarkably, both compounds were successfully isolated in quantifiable yields. This synthesis protocol boasted several advantages, including low catalyst loading, omission of additives, broad substrate scope, straightforward product separation, and the ability to recover the catalyst up to eight times. In summary, this study effectively showcased the potential of continuous flow reactor technology in synthesizing stable and uniformly distributed nanoparticles. Conclusion:: Additionally, it highlighted the effectiveness of Ni nanoparticles as catalysts in various chemical reactions. The findings from this study hold significant implications for developing more efficient and sustainable chemical synthesis protocols.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"1 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140002511","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":"Apigenin Bioisosteres: Synthesis and Evaluation of their Antioxidant, Antimicrobial, and Anticancer Activities","authors":"Juhi Gupta, Kalyani Thombre, Krishna Gupta, Milind Umekar","doi":"10.2174/0115701786287193240215101054","DOIUrl":"https://doi.org/10.2174/0115701786287193240215101054","url":null,"abstract":": A novel series of Apigenin bioisosteres [1(4-chlorophenyl)-3-phenyl prop-2-ene-1-one] non-cyclic derivatives (4a-4c) and [7-hydroxy-2-phenyl-4H-chromen-4-one] cyclic derivatives (9a- 9d) were synthesized. The newly synthesized apigenin bioisosteres were confirmed using UV, IR, NMR, and mass spectroscopic methods. The antioxidant, antibacterial, and anti-cancer activities of all newly synthesized compounds were assessed using the DPPH free radical scavenging capacity, disc diffusion method, and in vitro MTT assay on the human breast cancer MCF-7 cell line. Almost all the synthesized apigenin bioisosteres had greater antioxidant and antimicrobial activity than standard Apigenin. Out of seven compounds (4a-4c and 9a-9d), five compounds were found to exhibit notable antiproliferative activity on the breast cancer cell line (MCF-7), whereas two compounds, 9c and 9d, did not show notable activity. Our analysis suggests that synthesized Apigenin bioisosteres function as prospective antioxidant, antimicrobial, and anticancer agents.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"36 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140002248","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":"Fireballs-Like Explosive Peroxides Produced by the Brown-rot Fungus","authors":"Gerson S. Paiva","doi":"10.2174/0115701786267733240215043302","DOIUrl":"https://doi.org/10.2174/0115701786267733240215043302","url":null,"abstract":": Fireballs are unusual and rare phenomena usually associated with thunderstorms, although sometimes they have been observed during earthquakes, volcano eruptions or in fair weather. There are still questions about their origination, features and interaction with the environment. In this work, a new model is shown to explain the formation of fireballs in fair weather from poplar cotton and peroxides produced by brown-rot fungi. Light emission is produced via thermal decomposition of 1,2- dioxetane phenylcoumarane or 1,2-dioxetane monolignol, from lignin inside the poplar fibers. The energy released during the explosive decaying of fireballs was calculated as being about 3 kilojoules for each gram. This value is the same order of magnitude as the estimated for the explosive fireballs decaying.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"36 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140002195","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":"Recent Advances in Biginelli Reaction using Nanoparticles, Zeolites and Metal Compounds as Catalyst: A Concise Review","authors":"Bhaktiben R Bhatt, Dr. Bharat C. Dixit, Dr. Vipul B. Kataria, Dr. Ritu B. Dixit, Shaffiq Saiyad","doi":"10.2174/0115701786291084240206113913","DOIUrl":"https://doi.org/10.2174/0115701786291084240206113913","url":null,"abstract":":: The year 1891 is considered as a historic year in chemical science due to the introduction of novel heterocyclic compounds by P. Biginelli. The classical Biginelli reaction offers 3,4- dihydropyrimidin-2(1H)-ones/thiones in occupancy of acids like Broansted and Lewis. Multifaceted Dihydropyrimidones (DHPMs) have gained much importance due to their high biological activities. Several nanoparticles, zeolites and metal compounds are disclosed to improve the yield of this product. This review subsumes the evolution and effectiveness of catalysts. It summarises the main synthetic routes which are known to obtain DHPMs using these catalysts. The majority of these catalysts delivered satisfying catalytic activity which was more than 80% in the vicinity of producing Biginelli adducts. We hope this review article will be useful to researchers in terms of obtaining higher yields in a shorter time using easily available and reusable catalysts.","PeriodicalId":18116,"journal":{"name":"Letters in Organic Chemistry","volume":"3 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139950416","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}