反应详情

A mixture of 2.61 g (11.1 mmole) of diacetylguanine (VII), 5.50 g (22.2 mmole) of acetoxymethyl 2,3-diacetoxy-1-propyl ether from Step A above and 55 mg of ethanesulfonic acid was heated in a flask fitted with a distillation adapter under low vacuum in an oil bath at 155°-160°. The mixture gradually thinned enough to permit magnetic stirring, and some distillate was collected. The mixture became homogenous after about 45 minutes and was cooled after 75 minutes. The viscous oil as taken up in about 100 ml of ethyl acetate and induced to crystallize with a yield of 1.23 g (29%) of nearly white crystals, mp 162.5°-165°. Thin layer chromatography (TLC) (9:1 CHCl3 --CH3OH) showed a single spot.

1. customfitted with a distillation adapter under low vacuum in an oil bath at 155°-160°
2. distillationsome distillate was collected
3. temperaturewas cooled after 75 minutes
4. customto crystallize with a yield of 1.23 g (29%) of nearly white crystals, mp 162.5°-165°