A small molecule library of alkyl, sulfone, and carboxamide functionalized pyrazoles and isoxazoles has been developed via a rapid sequential condensation of various alpha-acylketene dithioacetals (1a-o) with hydrazine hydrate or hydroxylamine hydrochloride, followed by oxidation of sulfide to sulfone using water as the reaction medium. An efficient and safe oxidation of sulfides (4/5a-o) to the corresponding sulfones (6/7a-o) using sodium per borate system in aqueous medium is reported. The concise and two step synthesis of trisubstituted pyrazoles and isoxazoles was investigated under variety of reaction condition. The newly developed methodology has the advantage of excellent yield and chemical purity with short reaction time using water as a solvent.

No abstract

A simple, convenient and efficient one-pot cyclocondensation reaction of 1-(2-hydroxyphenyl)-2-nitroethanone, arylaldehydes and urea using etidronic acid to furnish nitro dihydropyrimidine derivatives is described. A new and efficient protocol is developed as a homogenous catalyst for the synthesis of dihydropyrimidines using substituted x-nitro acetophenone. Various bisphosphonic acids were examined to synthesized pyrimidines via multicomponent cyclocondensation reaction. This methodology has the advantage of excellent yields with short reaction time.

A solution-phase library of the title compounds (V) and (VIII) with methyl, sulfone and carboxamide moieties is prepared by a two-step synthesis starting from (IV) using water as a green solvent. -(SAVANT, M. M.; PANSURIYA, A. M.; BHUVA, C. V.; KAPURIYA, N.; PATEL, A. S.; AUDICHYA, V. B.; PIPALIYA, P. V.; NALIAPARA*, Y. T.; J.

The three component reaction between 4-hydroxycoumarin, malononitrile and carbonyl compounds in ethanol in the presence of morpholine as a catalyst was studied. Only cyclic aliphatic ketones afford spiro 2-amino-3-cyanopyrano[3,2-c]chromene derivatives.