In the past two decades, 6-mercaptopurine (6MP) and its analogues have been a synthetic target for SAR programs in therapeutic areas of cancer, 1 viral infections, 2 and in CNS as ligands for benzodiazepine receptors. 3 In one instance, there has been a report of it being clinically used in the treatment of leukemia. 1 In these reports, thiopurines are obtained by treating chloropurines with thiourea, [1], [3] and [4] NaSH/EtOH, 2 and in some cases with H 2 S/base. 5 These ...