反应详情

Two hundred mg of 2'-deoxy-2',2'-difluorocytidine, hydrochloride, was dissolved in 2 ml of pyridine, and then 134 mg of succinic anhydride was added. The mixture was stirred at ambient temperature for 1.25 hours, and was then concentrated under vacuum. The residue was dissolved in dichloromethane/methanol, and the solution was absorbed on 1.5 g of silica gel, which was then slurried in dichloromethane and loaded on a 4 g silica gel column. The column was eluted with a gradient solvent, starting with dichloromethane and ending with methanol. The product-containing fractions were combined and freeze-dried overnight to obtain 255 mg of product mixture. It was dissolved in 3 ml of 0.01M ammonium acetate, and was chromatographed on a 22 ml mono-Q fast flow column (Pharmacia Inc.), eluting with the ammonium acetate gradient buffer which has previously been described. Evaporation of the product-containing fractions gave 81 mg of a mixture of the mono-acylated products named in the heading.

1. concentrationwas then concentrated under vacuum
2. dissolutionThe residue was dissolved in dichloromethane/methanol
3. customthe solution was absorbed on 1.5 g of silica gel, which
4. washThe column was eluted with a gradient solvent
5. customfreeze-dried overnight