Synthesis and properties of dipyrimido-[4,5-b][5,4-f]-1,4-thiazepine derivatives

Abstract

Derivatives of dipyrimido [4,5-b][5,4-f]-1,4-thiazepine were synthesized and some of their properties were studied.Continuing our reports on the search for biologically active substances among bi-and tricyclic 1,4-thiazine and 1,4-thiazepine systems [1, 4], we present here the synthesis of derivatives of the previously unknown heterocyclic dipyrimido [4,5-b][5,4-f]-1,4-thiazepine system.The interaction of 5-amino-6-mercaptopyrimidines I-V with 5-formyl-6-chloropyrimidine derivatives VI was studied. The primary products of the reaction of 4-dimethylamino-, 4-methylamino-, 4-methoxy-, and 4-methylthio-5amino-6-mercaptopyrimidines (I -IV) with 4-chloro-5-formyl-6-aminopyrimidine (VI) in methanol at 60 -65°C in the presence of an equimolar quantity of KOH were dipyrimidylsulfides VII -X.The IR spectra of compounds VII -X had absorption by an NH 2 group (3200 -3600 cm -1 ) and an aldehyde group (1680 cm -1 ), and the 1 H NMR spectrum showed signals from the CHO group with d 10.2 -10.3 ppm and from protons in the pyrimidine rings at C-2 and C-2¢ with d 7.77 -8.08 ppm, which is consistent with their structures. I, VII: R = N(CH 3 ) 2 ; II, VIII: R = HN(CH 3 ); III, IX: R = OCH 3 ; IV, X: R = SCH 3 ; V: R = NH 2