LIGNANS AND NEOLIGNANS FROM STEMS AND FRUITS OF PIPER WIGHTII

Two new neolignans, -methylenedioxy-6'oxo-Delta-(1',4',8')-8.3'-lignan (1) and -methylenedioxy-6'oxo-Delta-(1',4',8')-8.3'-lignan (2) were i solated from the petroleum ether extract of stems of Piper wightii Miq . The structures were elucidated on the basis of their spectroscopic a nalysis and chemical transformation. Additionally five known neolignan s, isodihydrofutoquinol A (3) and B (4), lacifolin C (5) and D (6) and wallichinine (7) and two known ha'-diaryl-beta,beta'-dimethyltetrahyd robenzofuran lignans, calopiptin (8) and machilin G (9), were isolated for the first time from Piper wightii. The new neolignan 2, isodihydr ofutoquinol B (4), lancifolin C (5) and wallichinine (7) were also iso lated from the methanolic extract of fruits of the same species alongw ith gelbelgin (10), also a known lignan of the tetrahydrobenzofuran ty pe.