Synthesis and Antimicrobial Evaluation of Some New Pyrazolo[1,5-a]pyrimidine and Pyrazolo[1,5-c]triazine Derivatives Containing Sulfathiazole Moiety

A number of important fused heterocyclic systems have been prepared by the reaction of 4-((3,5-diamino-1H-pyrazol-4-yl)-diazenyl)-N-(thiazol-2-yl)-benzenesulfonamide with some bifunctional nucleophiles such as ethyl acetoacetate, acetylacetone or arylidenemalonononitrile derivatives to obtain pyrazolo[1,5-a]pyrimidine derivatives. The structures of the newly synthesized compounds were determined based on their IR, 1H and 13C NMR and mass spectroscopic data. Most of the compounds produced showed good antibacterial and antifungal activity

Visible-light driven synthesis of polycyclic benzo[d][1,3]oxazocine from 2-aminochalcone

Herein, we report a tandem cycloisomerization/nucleophilic addition/cyclization of 2-amino chalcone with bifunctional nucleophiles driven by visible light.

Palladium-catalyzed tandem allylic substitution/cyclization and cascade hydrosilylated reduction: the influence of reaction parameters and hydrosilanes on the stereoselectivity

Pd-catalyzed AAA of 1,2-bifunctional nucleophiles and one-pot tandem allylic cyclization/reduction gave corresponding heterocycle products with promising enantioselectivity in good yields.

Synthesis of Novel Five- and Six-Membered Ferrocene-Containing Heterocycles and Heteroaromatics via Cyclocondensation of 1-Ferro­cenyl-3,3-bis(methylthio)prop-2-en-1-one with Various Bifunctional Nucleophiles

Synthesis and reactions of 1-ferrocenyl-3,3-bis(methylthio)prop-2-en-1-one as a versatile 1,3-bielectrophilic synthon leading to a range of novel ferrocene-containing five- and six-membered heterocycles and heteroaromatics has been reported. Thus its cyclocondensation with various bifunctional heteronucleophiles, such as hydrazine­, phenylhydrazine, hydroxylamine, guanidine, and amidine, affords­ a range of ferrocene-substituted pyrazoles, oxazoles, and pyrimidines in highly regioselective manner. Synthesis of few ferrocenyl-substituted pyridines and thiophenes has also been described. Similarly cycloaromatization of this ferrocene-substituted α-oxoketene dithioacetal with anions generated from (het)arylacetonitriles provides a facile entry to ferrocene-substituted heteroaromatics in good yields. Synthesis of a few 2-ferrocenylvinyl-substituted heterocycles, such as pyrazoles, isoxazoles, and pyrimidines, via cyclocondensation of a novel 5-ferrocenyl-1,1-bis(methylthio)penta-1,4-dien-3-one with phenylhydrazine, hydroxylamine, and guanidine has also been reported.