Triterpenoids from Grewia plagiophylla K. Schum

Introduction: Plants of the genus Grewia have been used as medicinal agents to treat several diseases. Grewia species are reported in use as folk medicine for the treatment of malaria, diarrhoea, dysentery, typhoid fever, small pox, cough, irritable condition of intestine and bladder among others. Methods: The stem back material of Grewia plagiophylla was extracted using CH2Cl2: MeOH (1:1). Fractionation and Isolation of the extract was done using column chromatography with silica gel and eluting with hexaneethyl acetate solvent system in increasing polarity. The structures of the isolated compounds were elucidated on the basis of NMR experiments and the comparison of their spectroscopic data with literature values. Results: Studies on bioactive components of the stem back of Grewia plagiophylla led to isolation of three triterpenoids: stigmasterol (I), butelin (II) lup-20(29)-en-3-ol (III). The triterpenoids have been isolated for the first time from this species with compound (III) being reported for the first time from the genus of Grewia. The isolated compounds showed varying degrees of in vitro antimalarial activity against Plasmodium falciparum chloroquine-sensitive D6 and chloroquine-resistance W2 strains with significant cytotoxic activity against Vero cells.