intraperitoneally to rats. The catabolic products of each of these compounds in the 24-hour urine after injection in these rats were determined. 6-MP-S36 was excreted primarily as thiouric acid. 9-Methyl and 9-ethyl-6-MP-S35 were primarily excreted unaltered, and no evidence of dealkylation was obtained. The import of these findings on the possible mechanism of action of 6-MP against neoplastic...

For the past half century, thiopurines have earned themselves a reputation as effective anti-cancer and immunosuppressive drugs. Thiopurine S-methyltransferase (TPMT) is involved in the metabolism of all thiopurines and is one of the main enzymes that inactivates mercaptopurine. 6-MP is now used as a combination therapies for maintenance therapy of children with acute lymphocytic leukemia (A...