反应详情

In preferred embodiments of the present invention, CldAdo is synthesized by employing acetyl chloride and benzyltriethylammonium nitrite (BTEA-NO2)-mediated diazotization/chloro-dediazoniation of 6-O-(2,4,6-triisopropylbenzenesulfonyl) (TiPBS) or 6-chloro derivatives that are readily obtained from dGuo. Non-aqueous diazotization/chloro-dediazoniation (acetyl chloride/benzyltriethylammonium nitrite) of 2, 2′b, or 5 gave the 2-chloropurine derivatives 3, 3′b, or 6, respectively. This new procedure for non-aqueous diazotization/chloro-dediazoniation27 (AcCl/BTEA-NO2/CH2Cl2/−5 to 0° C.) worked well for replacement of the 2-amino group of 2, 2′b, and 5 with chlorine to give 3a (89%), 3b (90%), 3′b (87%), 6a (95%), and 6b (91%).

1. customare readily obtained from dGuo