11-Isopropylcryptolepine:  A Novel Alkaloid Isolated from <i>Cryptolepis sanguinolenta</i> Characterized Using Submicro NMR Techniques

A new alkaloid has been isolated from extracts of the West African plant <i>Cryptolepis sanguinolenta</i> and identified by submicro NMR techniques as 11-isopropylcryptolepine (<b>1</b>). The unusual incorporation of the isopropyl group at the 11-position of the indolo[3,2-<i>b</i>]quinoline nucleus is suggestive of a mixed biosynthetic origin for the alkaloid.