Trifluoroacetic acid → HCID 59238206, compound

Participants

Reaction Steps

To a stirred mixture of crude 4 (7 g) in CH2Cl2 (200 ml) was gradually added CF3CO2H (200 ml). The mixture was stirred overnight. Then potassium carbonate was added to adjust the pH to 7.5. Saturated aqueous sodium bicarbonate solution was then added to keep the pH 8-9. After the adjustment of the pH, Fmoc-OSuc (10 g) in THF was added to the mixture and it was stirred for further 5 hours. THF was evaporated and the mixture was washed with ethyl acetate (150 ml×2). The water layer was tuned the pH to 3 with 2N HCl and then extracted with dichloromethane (150 ml×7). The organic layer was dried over Na2SO4 and concentrated to give the crude product (0.5 g). Further purification by preparative HPLC afforded 4-(6-amino-7-carboxymethyl-7H-purin-2-yl)-piperazine-1-carboxylic acid 9H-fluoren-9-ylmethyl ester, 6 (50 mg).

Provenance & Evidence