A rare isoprene coumarin, toddayanin (1), and a new dihydrochelerythrine-cadinane derivative, toddayanis (2), along with 16 known compounds were isolated from the root of Toddalia asiatica Lam. Compound 12 showed strong antimalarial activity against Plasmodium falciparum with an IC50 value of 5.4μg/mL and was inactive against normal, Vero cells. Compound 13 showed cytotoxicity against the MCF-7 cell line with an IC50 value of 8.7μg/mL and was inactive against Vero cells. Alkaloid 11 displayed cytotoxicity against KB, NCI-H187, MCF-7 and Vero cells lines with IC50 values ranging from 0.8 to 11.6μg/mL.