A new sesquiterpene evoninoate alkaloid, hippocrateine III, was isolat
ed together with the known compound mayteine from the root and stem ba
rks of Hippocratea excelsa. The structures of both compounds were eluc
idated by interpretation of spectral data. The substitution pattern of
the nicotinic acid moiety in hippocrateine III differs from that of e
marginatine A and hippocrateines I and II.