A series of 4-phenethynyldihydrocinnamic acid agonists of the free fatty acid receptor 1 (FFA1) has been discovered and explored. The preferred compound 20 (TUG-424, EC50 = 32 nM) significantly increased glucose-stimulated insulin secretion at 100 nM and may serve to explore the role of FFA1 in metabolic diseases such as diabetes or obesity.