6-Chloropurine (6-CIPH), a 6-substituted purine derivative, is an antileukemic drug. It can be prepared by the chlorination of hypoxanthine with phosphorus oxychloride in the presence of dimethylaniline. The NMR-based conformational analysis of the products formed during the reaction of 6-CIPH with 3,4-di-O-acetyl-D-xylal and 3,4-di-O-acetyl-L-arabinal have been reported.