Main glucosidase conversion products of the gluco-alkaloids dolichantoside and palicoside.

The enzymatic glucose cleavage of palicoside revealed the biosynthetic pathway to akagerine, whereas the conversion of dolichantoside led to a new quaternary heteroyohimbine alkaloid named N(b)-methyl-21-beta-hydroxy-mayumbine. The hypothetical models of reactions occurring after the conversion of both substrates are proposed. Dolichantoside and palicoside, as well as Strychnos mellodora stem bark crude ethanol extract, exhibit significant antimycotic activity against human pathogens in presence of specific glucosidase.