A stereospecific synthesis of some thiazolidinones and thiazoles was achieved conveniently through certain α-halo keto agents and reactivity of chloroacetyl chloride was successfully enhanced by CsF–Celite + CH3COONa. NMR studies revealed that the configuration of N–N bond is found to be anti with respect to C-3 alkyl group while CN bond in thiazolidinone is trans with respect to N–N bond. Antimycobacterial