Abstract Valganciclovirhydrochloride (1) is used for the treatment of cytomegalovirus (CMV) retinitis in patients with weakened immune systems. Valganciclovirhydrochloride is a hydrochloride salt of L-valyl ester of ganciclovir (2) that exists as a mixture of two diastereomers. According to the U.S. Food and Drug Administration specifications, the diastereomeric ratio of valganciclovir hydrochloride