Synthesis and In Vivo Acute Antihyperglycemic Evaluation of Novel Isosteviol Derivatives

Isosteviol is a beyerane tetracyclic diterpenoid with a large variety of biological activities. In this article, a series of novel isosteviol derivatives containing the modification of C-18 carboxyl group (5-12), C-16 carbonyl group (14-16) and heteroatom-containing frameworks fused with isosteviol structure (18-19) were synthesized and evaluated for their in vivo acute antihyperglycemeric effects. Among them, compound 8 exhibited the most potent antihyperglycemeric effects. Furthermore, primarily, structure-activity relationship (SAR) was also analyzed. The structures of all the newly synthesized compounds were determined by H-1, (CNMR)-C-13, MS, IR and elementary analysis.