Transformações químicas de lignanas isoladas de Virola sebifera em análogos de podofilotoxina

The chloroform extract of leaves of Virola sebifera was fractioned leading to isolation of lignans (2R, 3R) -2, 3-Di- (3', 4' -dimethoxybenzyl) -butirolactone (1) (2R, 3R) -2, 3- Di- (3', 4' -methylenedioxybenzyl) -butyrolactone (2), (2R, 3R) -3- (3'', 4'' -dimethoxybenzyl) -2- (3', 4' -methylenedioxybenzyl) -butyrolactone (3). Transformation of these lignans intopodophyllotoxin analogs (4) was tested experimentally with negative results. In the proposed transformation (2R, 3R) -2, 3-Di- (5-bromo-3', 4' -dimethoxybenzyl) -butyrolactone (5) was obtained.