Regioselective synthesis of new 5H,10H-dipyrimido2,1-b:4 ',5 '-d1,3thiazine: a combined experimental and computational study

摘要

Several derivatives of the novel tricyclic system 'dipyrimido2,1-b:4 ',5 '-d1,3thiazine' were synthesized via inter- and intramolecular heterocyclization of 2,4-dichloro-5-(chloromethyl)-6-methylpyrimidine and 6-amino-4-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile in short reaction times under mild conditions. An x-ray analysis together with computational calculations was performed to gain an in-depth understanding of regioselectivity of the reaction.