Synthesis and SAR of 1,3-thiazolyl thiophene and pyridine derivatives as potent, orally active and S1P3-sparing S1P1 agonists

A series of 1,3-thiazole derivatives were synthesized as potent, orally bioavailable S1P3-sparing S1P1 agonists. One of them, 24c, exhibited favorable efficacy in rat on host versus graft reaction (HvGR). The pharmacokinetic data for other compounds are shown as well.