Synthesis and hypolipidemic activities of 5-thienyl-4-oxazoleacetic acid derivatives.

A series of 2,5-disubstituted 4-oxazoleacetic acid derivatives was synthesized and evaluated for hypolipidemic activity. Among them, those with a thienyl group at C-5 of the oxazole ring exerted highly potent hypolipidemic effects in rats. 2-(4-Fluorophenyl)-5-(3-thienyl)-4-oxazoleacetic acid (88) was the most potent derivative: it was about 2 times as active in normal SD male rats and about 4 times as active in hereditary hyperlipidemic rats (THLR/1) as clofibrate with an improved antiarteriosclerosis index (HDL-Cho/Total-Cho). In addition, it showed inhibition of platelet aggregation ex vivo.