In our continued efforts to explore the antidiabetic potential of pregnanes from Apocynaceae, especially Asclepiadoideae subfamily, sixteen derivatives 1-16 previously isolated various Cynanchum species, have been evaluated for their ability increase glucagon-like peptide-1 (GLP-1) release in a cell assay. As result, otophylloside A (2), wilfoside C1N (13), and C3N (16) were found stimulate sig...