Process for isolating 2-amino-6-chloro-9-(1'S,2'R)-1'2'-bis(hydroxymethyl)-cyclopropane-1'-YLmethylpurine and an optical isomer thereof

摘要

A process for purifying 2-amino-6-chloro-9-(1S,2R)-1,2-bis(hydroxymethyl) cycdopropane-1-ylmethylpurine represented by the following formula (5) comprises the step of selectively isolating 2-amino-6-chloro-9-(1S,2R)-1,2-bis(hydroxymethyl) cyclopropane-1-ylmethylpurine from a mixture of 2-amino-6-chloro-9-(1S,2R)-1,2-bis(hydroxymethyl)cyclopropane-1-ylmethylpurine and 2-amino-6-chloro-7-(1S,2R)-1,2-bis(hydroxymethyl)cyclopropane-1-ylmethylpurine represented by the following formula (6) by the crystallization. This process has a satisfactory medicinal quality on an industrial scale without necessitating complicated operations such as chromatographic purification.