Isolation and chemical modification of clerodane diterpenoids from Salvia species as potential agonists at the kappa-opioid receptor.
Chemistry & biodiversity July 1, 2007 Yiqiang Li, Stephen M Husbands, Mary F Mahon et al.
Salvinorin A, the active component of Salvia divinorum, is a potent kappa-opioid receptor agonist. Computer modeling suggested that splendidin from Salvia splendens and related compounds might have similar activity. However, none of the tested compounds showed significant binding to mu-, delta-, or kappa-opioid receptors, disproving that hypothesis. Two novel compounds were obtained semi-synthetically from salvifarin isolated from Salvia farinacea. The X-ray crystal structure of salvifaricin was determined for the first time and used to elucidate absolute configurations of new products. The relatively accessible diterpenoid salvifaricin could serve as starting material for future structure-activity relationship studies at the kappa-opioid receptor.