Aminomethylation of pyrimidines

Aminomethylation of not yet described 5-hydroxy-6-methyluracil, 3-isobutylt kioethyl-6-methyluracil, and 4-amino-6-hydroxy-2-methylpyrimidine. The amin omethylation of 5-hydroxy-6-methyluracil with morpholine or piperidine occu rs in position 3 irrespective the ratio of original reagents whereas at an equivalent amount of piperazine it attacks position 3, and at excess both p ositions 3 and 1. The aminomethylation with an equivalent amount of piperaz ine occurs with 3-isobutylthioethyl-6-methyluracil and 4-amino-6-hydroxy-2- methylpyrimidine at position 5 of pyrimidines. At the ratio of 5-hydroxy-6- methyluracil, 3-isobutylthioethyl-6-methyluracil, or 4-amino-6-hydroxy-2-me thylpyrimidine : formaldehyde : piperazine equal to 2:2:1 forms 1,4-bis(5-p yrimidinylmethyl)piperazine.