3-(4-methoxybenzyl)pyrazolo[3,4-b]pyrrolo[3,4-d]pyridine-6,8(3H,7H)-dione → pyrazolo[3,4-b]pyrrolo[3,4-d]pyridine-6,8(3H,7H)-dione

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Reaction Conditions

Reaction Steps

3-(4-methoxybenzyl)pyrazolo[3,4-b]pyrrolo[3,4-d]pyridine-6,8(3H,7H)-dione (100 mg, 0.32 mmol) was dissolved in trifluoroacetic acid (5 ml) and heated to 65° C. for 24 hours. The mixture was concentrated under reduced pressure and partitioned between ethyl acetate (100 ml) and saturated aqueous sodium bicarbonate (50 ml). The organic layer was dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The crude product was treated with ethyl acetate (3 ml) and a few drops of methanol and cooled to 0° C. The mixture was filtered and washed with ice cold ethyl acetate to afford pyrazolo[3,4-b]pyrrolo[3,4-d]pyridine-6,8(3H,7H)-dione (28 mg, 47%) as a yellow solid. M.p.=285-300° C.; 400 MHz 1H NMR (DMSO-d6) δ: 11.55 (bs, 1H), 8.98 (s, 1H), 8.50 (s, 1H); LCMS: 189 [M+H].

Provenance & Evidence