Synthesis of γ-butyrolactone hybrid imidazo[2,1-b][1,3]-thiazoles from limonene

The substituted γ-butyrolactones are important structural motifs in several natural products and pharmaceuticals. In this paper γ-butyrolactone fused heterocyclic imidazo[2,1-b][1,3]-thiazole derivatives have been synthesized from thiazole amine (4) and different substituted α-bromo acetophenones in moderate yields. Electron rich substituents provided higher yields of the desired products. The screening results of physicochemical properties indicated that all the synthesized heterocyclic molecules could be good drug candidates.