Convergent synthesis and biological evaluation of 3-[2-(benzylidenehydrazinyl)thiazol-4-yl]-4-hydroxycoumarins

Abstract

A convenient synthesis of a small library of 4-hydroxycoumarin derivatives, containing thiazole and benzylidenehydrazine moieties has been achieved, using 2-hydroxyacetophenone and aryl-and heteroaryl aldehydes as starting materials. In vitro biological studies revealed that some of the compounds exhibited modest activities, viz.; anti-malarial (65% PLDH viability), anti-trypanosomal (52% T.b.brucei viability), antimycobacterial (Visual MIC90 5.63 M) and anti-bacterial (restricting S.aureus metabolic activity after 6 h).

Synthesis and exploratory biological evaluation of 3-[(N-4-benzyloxyphenyl)iminoethyl]- and 3-(1-hydrazonoethyl)-4-hydroxycoumarins

“…Attention has been given to the synthesis of novel furocoumarins 4 -designed to serve as HIV-1 Integrase inhibitors 19 -and coumarin-AZT conjugates as portmanteau HIV-1 protease and reverse transcriptase inhibitors. 20 Access to 4-hydroxycoumarins, however, has required the application of a different methodology and, in a recent study, 21 we made use of a procedure developed by Zhao et al 22 to access these systems. We now report the preparation and exploratory biological evaluation of three series of compounds containing 4hydroxycoumarin, iminoethyl , hydrazonoethyl and alkynyl moieties.…”