N1,N2,N3-trisisopentenyl guanidine and n1,n2-diisopentenyl guanidine, two cytotoxic alkaloids from alchornea cordifolia (schumach.& thonn.) müll. arg. (euphorbiaceae) root barks

Abstract

This paper describes the purification of two guanidine alkaloids: N1, N2-diisopentenyl guanidine (DIPG) 1 and N1,N2,N3- triisopentenyl guanidine (TIPG) 2 from Alchornea cordifolia root bark and reports their cytotoxic properties on cancer (HeLa, Mel-5, J774) and non cancer (WI 38) cells. TIPG showed the highest cytotoxicity with IC50 values from 0.7 to 14.3 μg/mL (2.6 to 54.3 μM) on the four cell lines while DIPG was much less active: IC50 45.8 and 97.6 μg/mL (234.8 and 500.5 μM) on Mel-5 and HeLa and > 512.8 μM on J774 and WI 38. The results indicate that the cytotoxicity notably decreased with the loss of one isopentenyl substituent.