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991.
Thionyl chloride-mediated chalcogenation of imidazo[1,5-a]pyridine serves as a new protocol for the synthesis of rare bisimidazopyridyl sulfides. This method provides the new route to synthesis of 2-azaindolizine sulfur-bridged dimers called chalcogenide under metal-free, elemental sulfur-free conditions without the use of polar solvents in regio-selective manner, at room temperature with the simple operational procedure. 相似文献
992.
Chetan K. Jadhav M.Sc NET Amol S. Nipate M.Sc NET Asha V. Chate Ph.D. Anil P. Patil Ph.D. Charansingh. H. Gill Ph.D. Professor 《Journal of heterocyclic chemistry》2020,57(12):4291-4303
The synthesis of a combinatorial library of heterocycle-fused pyridine derivatives has been achieved successfully via a one-pot four-component reaction of aromatic/aliphatic aldehyde, malononitrile, thiazolidine-2,4-dione and ammonium acetate in the presence of piperidinium acetate as the catalyst. It involved the Knoevenagel condensation of the aldehyde and malononitrile to produce arylidene malononitrile as an intermediate, which was further intramolecular cyclization through Michael type addition ketone to the electrophilic double bond of the arylidene to produce fused pyridines in high yields. Environmental friendliness, low cost, Operational simplicity, extensive reusability and applicability, and easy recovery of the catalyst using simple evaporation are the critical features of this methodology. Also, a series of pyridine based dihydrothiazolo[4,5-b] pyridine-6-carbonitrile analogs were synthesized and selected for their in vitro antifungal and antibacterial activities. 相似文献
993.
Patil Amod S. Mundada Anand B. Shravane Ravindra S. Mundada Pooja A. Surana Sanjay J. 《平面色谱法杂志一现代薄层色谱法》2023,36(1):89-97
JPC – Journal of Planar Chromatography – Modern TLC - Two new, simple, fast, and sensitive methods, normal- and reversed-phase high-performance thin-layer chromatography (NP-HPTLC and... 相似文献
994.
Lohar Trushant Kumbhar Arjun Patil Audumber Kamat Siddharth Salunkhe Rajashri 《Research on Chemical Intermediates》2019,45(3):1639-1651
Research on Chemical Intermediates - A novel DABCO-based cationic surfactant [C18-Dabco][Br] has been easily synthesized by the reaction of DABCO and octadecyl bromide in acetonitrile at room... 相似文献
995.
Ravindra D. Yeole Vipul P. Rane Vinod K. Ahirrao Rajesh P. Chavan Anasuya M. Patel Prasad K. Deshpande Mahesh V. Patel Kiran R. Patil 《Biomedical chromatography : BMC》2019,33(7)
WCK 771 is an l ‐arginine salt of levonadifloxacin (LND) being developed in intravenous dosage form and has recently completed a phase III trial in India. The pharmacokinetics of WCK 771, a novel anti‐MRSA fluoroquinolone, were examined in mice, rats, rabbits, dogs, monkeys and humans after systemic administration during pre‐clinical and clinical investigations. Urine and serum were evaluated for identification of metabolites. It was observed that LND mainly follows phase II biotransformation pathways. All of the species showed a different array of metabolites. In mice, rabbit and dog, the drug was mainly excreted in the form of O‐glucuronide (M7) and acyl glucuronide (M8) conjugates, whereas in rat and human major metabolite was sulfate conjugate (M6). Monkeys exhibited equal distribution of sulfate (M6) and glucuronide conjugates (M7, M8). In addition to these three major phase II metabolites; five phase I oxidative metabolites (M1, M2, M3, M4 and M5) were identified using liquid chromatography tandem mass spectrometry. Out of these eight metabolites M2, M3, M5, M7 and M8 are reported for the first time. 相似文献
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Rahul Suryawanshi Chandrashekhar Patil Hemant Borase Chandrakant Narkhede 《Natural product research》2015,29(4):353-358
Rubiaceae and Apocynaceae families are well known for the expression of cyclotides having insecticidal properties. Leaves and flowers extracts of plants from the families Rubiaceae (Ixora coccinea) and Apocynaceae (Allamanda violacea) were evaluated for mosquito larvicidal effect against early IVth instars of Aedes aegypti and Anopheles stephensi. Two forms of plant extracts, one untreated and the other treated with heat and proteolytic enzyme were used for assay. After primary assay, the extract showing more than 50% inhibition was further used for quantification purpose. LC50 and LC90 values of all the extracts were found to be reduced with the treated form. Phytochemical analysis of plant extracts was performed. Primary confirmation for the presence of cyclotides was done by Lowry test, thin layer chromatography and haemolytic assay. This novel approach merits use of plant extracts in mosquito control programmes. 相似文献
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