New neolignans from Talauma ovata.

The hexane extract of the bark of Talauma ovata yielded three new natural neolignans, identified as acetyl oleiferin-C (4), acetyl oleiferin-F (7) and acetyl oleiferin-G (8), together with the known compounds dihydroguaiaretic acid (1), austrobailignan-5 (2), oleiferin-C (3), austrobailignan-6 (5) and oleiferin-F (6).