Total synthesis and biological evaluation of methylgerambullone

First total synthesis of methylgerambullone (MGB, 1) isolated from Glycosmis angustifolia was completed via a convergent route. The effect of MGB on the contractile responses of the isolated guinea-pig ileum induced by acetylcholine was investigated. As a result, it showed a potent relaxation rate (78.66 +/- 4.30% at 100 mg/L) in a concentration-dependent manner on longitudinal smooth muscle contraction of isolated guinea-pig ileum induced by 1 mu M acetylcholine. (C) 2009 Elsevier Ltd. All rights reserved.