One-pot multi-component synthesis of 4-substituted thiazole Schiff base derivatives and their antibacterial activity

A series of 4-substituted thiazole Schiff base derivatives (6a-h, 7a,b and 8a,b) have been synthesized via one pot multi component condensation of 1-tetralone derivatives with thiosemicarbazide and 4-substituted phenacylbromides/3-(2-bromoacety1)-2H-chromen-2-one/2-(2-bromoacety1)-3H-benzo[f]chromen-3-one under conventional heating in absolute ethanol using catalytic amount of acetic acid with good yields. All the synthesized compounds have been characterized by their IR, H-1 and C-13 NMR, mass spectra and elemental analyses and also assessed for their antibacterial activity against both Gram positive and Gram negative bacterial strains. Compounds 6h, 7a, 7b, 8a and 8b have shown excellent activity against tested bacterial strains when compared to standard drug Gentamicin.