Haplophytin-A and B: the alkaloidal constituents of Haplophyllum acutifolium.

During the phytochemical investigation of Haplophyllum acutifolium, two alkaloids named haplophytin-A (1) and B (2) have been obtained. In addition, some known constituents: flindersine (3), kusunokinin (4), beta-sitosterol, oleanolic acid, cholesterol and hexadecanoic acid, have also been obtained. The known constituents have never been obtained from this source. The structures of all the isolated constituents were elucidated by spectroscopic means. However, the structures of constituents 1 and 2 were further confirmed through HMBC technique.