We report here a novel IBX-promoted oxidative coupling of primary amines and its utilization to Ugi reaction. Advantageously, the reaction could be carried out in choline chloride urea as a natural deep eutectic solvent. A range of imines and bisamides from pseudo-four-component oxidative Ugi reaction could be synthesized under mild and metal-free conditions. Advantageously, the oxidant (IBX) and solvent could be recycled up to five times with only a slight loss in activity.
The broad applicability of the hitherto unexplored reagent combination PPh3·HBr-DMSO is exemplified with multiple highly diverse one-step transformations to synthetically useful building blocks, such as flavones, 4H-thiochromen-4-ones, α-hydroxy ketones, 1,4-naphthoquinones (including vitamin K3), 2-bromo-3-substituted-1H-1-indenones, 2-methylthio-1H-1-indenones, 3-butyne-1,2-dione, and 4-pentene-2,3-diones. The simple and mild reaction conditions make the reagent superior in terms of yield and substrate scope in comparison with the existing alternatives.
The investigation of microbiome-derived metabolites is important to understand metabolic interactions with their human host. New methodologies for mass spectrometric discovery of undetected metabolites with unknown bioactivity are required. Herein,...
Sulfur is an essential element of life. Thiol-containing metabolites in all organisms are involved in the regulation of diverse biological processes. Especially, the microbiome produces bioactive metabolites or biological intermediates...
Chiral, substituted 3-formylfuransh ave found widespreada pplications as synthetic intermediates and are key structural motifs in av ariety of bioactive natural products. However, methodsf or their preparation are scant. We report herein an efficient and generalr oute to synthesize them from suitably protected 2-iodoenones derived from glycals. The syntheticp rotocol involves Heck coupling between substituted 2-iodoenones and olefinsf ollowed by N-bromosuccinimide (NBS)-mediatede lectrophilicc yclization sequence, using H 2 Oa sanucleophile.S imilarly,afully substituted chiral 3-formylfuran can be prepared utilizingatwostep approach startingw ith b-methylstyrene as an olefinic partner in the Heck coupling. Further,t od emonstrate the potentialo fo ur method, we have synthesized af uro[3,2c]pyranderivative and af ully protectedc hiral furan.Scheme3.Substrate scope for unactivatedo lefins. Reactions were carried out with 1 (0.1 g) under the reaction conditionsi nScheme 2, and isolated yield is shown. 2qa-qc,2ra-rc,and 2sa-sc wereinseparable mixtures
Oxadiazoles are a class of heterocyclic aromatic chemical compound of azole family. Oxadiazole is five membered heterocycle having two carbons, two nitrogen, one oxygen and two double bonds. Oxadiazole exists in four isomeric forms depending upon the position of nitrogen atom in the ring. Benzimidazole is a heterocyclic aromatic compound. This bicyclic compound consists of fusion of benzene and imidazole. Benzimidazole may also be considered as cyclic analogues of imidines due to tautomerism effect. In the present study involves synthesis of1,3,4-oxadiazolyl benzenesulphonylbenzimidazole derivatives. All the synthesized compounds were screened against HepG-2 cell line to determine the growth inhibitory effect of compounds.All the synthesized compounds possessed good to moderate anti-cancer activity as compare to standard drug Adriamycin. Two of the synthesized compounds i.e. 8a and 8f were found to possess maximum anti-cancer activity.The structures of the synthesized compounds were established by IR and 1HNMR.
Chiral Substituted 3-Formylfurans from Carbohydrates: An Expedient Route via N-Bromosuccinimide (NBS)-Mediated Electrophilic Cyclization. -The efficient and general method for the synthesis of the title furans involves a Heck coupling between substituted iodoenones and olefins followed by NBS-mediated electrophilic cyclization using H 2O as a nucleophile. The cyclization reactions of Heck products containing unactivated olefines lead only to traces of the desired products. -(MAL, K.; KAUR, A.; DAS*, I.; Asian J.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.