New cytotoxic cycloartane triterpene from Cassia italica aerial parts

Phytochemical study of the aerial parts of Cassia italica Mill. (family: Fabaceae) growing in Saudi Arabia afforded one new cycloartane triterpene, named (22E)-3-beta-hydroxycycloart-22-en-24-one (2), together with eight known compounds: beta-sitosterol (1), uvaol (3), daucosterol (4), methyl 3,4-dihydroxybenzoate (5), emodin (6), 4-hydroxypheny-O-beta-D-glucopyranoside (7), aloin (8) and rutin (9). The structure of the isolated compounds was determined by physical, chemical and spectral data (UV, IR, MS, 1D (H-1, C-13 and DEPT) and 2D (H-1 H-1 COSY, HSQC and HMBC) NMR), as well as by comparing with authentic samples. Compounds 3-5 and 7-9 were isolated for the first time from the plant. Compound 2 was evaluated for its cytotoxic activity against the L5178Y and PC12 cell lines. The total methanolic extract and compounds 5-9 exhibited free radical-scavenging activity using DPPH assay.