Inhibitors of Cyclic AMP Phosphodiesterase in Picrasma quassioides BENNET, and Inhibitory Activities of Related β-Carboline Alkaloids

Abstract

Cyclic adenosine monophosphate (cAMP) phosphodiesterase inhibitors present in Picrasma quassioides BENN. were identified as 1-methoxycarbonyl-β-carboline, 4, 5-dimethoxycanthin-6-one and 5-hydroxy-4-methoxycanthin-6-one. The structure-inhibitory activity relationships were studied in 31 derivatives of β-carboline, 2 dimeric derivatives of β-carboline and 12 derivatives of canthin-6-one. β-Carboline derivatives with a methoxycarbonyl group and canthin-6-one derivatives with a methoxyl group generally had a strong inhibitory effect on cAMP phosphodiesterase.