NEW SEMISYNTHETIC DERIVATIVES OF A BENZYLISOTHIOCYANATE ISOLATED FROM Moringa oleifera AND EVALUATION OF THEIR CYTOTOXIC ACTIVITY

From the natural product 4-(4'-O-acetyl-α-L-rhamnosyloxy)benzylisothiocyanate (1), isolated from the flowers of Moringa oleifera Lam (Moringaceae), four new semisynthetic derivatives, N-[4-(4'-O-acetyl-α-L-rhamnosyloxy)benzyl]-2-(pyridinil-4-carbonil)hydrazine-1-carbothioamide (3), 4-(4'-O-acetyl-2',3'-dimesyloxy-α-L-rhamnosyloxy)benzylisothiocyanate (4), N-[(4'-O-acetyl-α-L-rhamnosyloxy)benzyl]hydrazinecarbothioamide (5), 4-[4'-O-acetyl-2',3'-O-bis(decanoiloxy)-α-L-rhamnosyloxy]benzylisothiocianate (6), and the known compound 4-(2',3',4'-O-triacetyl-α-L-rhamnosyloxy)benzylisothiocyanate (2), were obtained. All compounds were tested for their cytotoxicity against the tumor cell lines SF-295, HL-60, HCT-116 e PC-3. The natural product 1 and the semisynthetic derivatives 2 and 4 were the most active compounds (IC50 from16.0 to 3.7 µmol L-1) against all tumor cell lines.