Zhicai Yang

Asymmetric total synthesis of (+)-crassalactone D.

The asymmetric total synthesis of (+)-crassalactone D (4), a naturally occurring antitumor agent, has been achieved by employing an oxidative spirocyclization of furan 11 as the key step. Two close analogues, 7-epi-crassalactone D (14) and 5-epi-7-epi-crassalactone D (15), also have been prepared in the course of the synthesis of (+)-crassalactone D.

Discovery of 2-substituted benzoxazole carboxamides as 5-HT3 receptor antagonists

A new class of 2-substituted benzoxazole carboxamides are presented as potent functional 5-HT(3) receptor antagonists. The chemical series possesses nanomolar in vitro activity against human 5-HT(3)A receptors. A chemistry optimization program was conducted and identified 2-aminobenzoxazoles as orally active 5-HT(3) receptor antagonists with good metabolic stability. These novel analogues possess drug-like characteristics and have potential utility for the treatment of diseases attributable to improper 5-HT(3) receptor function, especially diarrhea predominant irritable bowel syndrome (IBS-D).

4-Phenyl tetrahydroisoquinolines as dual norepinephrine and dopamine reuptake inhibitors

Novel 4-phenyl tetrahydroisoquinolines that inhibit both dopamine and norepinephrine transporters were designed and prepared. In this Letter, we describe the synthesis, in vitro activity and associated structure-activity relationships of this series. We also report the ex vivo NET occupancy of a representative compound, 41.