A survey of alkaloids in Templetonia biloba (Benth.) Polhill (Fabaceae: Brongniartieae)

The presence of alkaloids in Templetonia biloba has been described for the first time. This species contained an unusual combination of α-pyridone alkaloids and tetra hydrocytisine derivatives with a fully saturated ring A. Cytisine, N-methylcytisine, tetra hydrorhombifoline, tetra hydrocytisine, N-methyl-tetrahydrocytisine, lupanine and 13-hydroxylupanine were found as major constituents. Other compounds that were identified include the bicyclic quinolizidine alkaloids lupinine and epilupinine. Together with the absence of ormosanine-type quinolizidines, which represent typical constituents for other species of Templetonia, these alkaloid data confirm morphological evidence that Templetonia biloba is probably misplaced in the genus Templetonia. Templetonia biloba was formerly thought to be a member of the genus Bossiaea. The alkaloid pattern of T. biloba supports its earlier removal from the genus Bossiaea, where quinolizidine alkaloids were totally missing and tyramine was found as a major compound.