Electrophilic and nucleophilic substitution in oxazolo[3,2-f]xanthines

Bromination of 2-aryloxazolo3,2-flxanthines gives the 3-bromoderivatives whereas 8-methyl-2-phenyloxazolo3,2-f]xanthine is nitrated in the para-position of the phenyl substituent. Alkylation of oxazolo3,2-f]xanthines by ethylmonoiodoacetate gives the ethyl esters of oxazolo3,2-f]xanthinyl-6-acetic acids. Reaction of oxazolo3,2-f]xanthines with sodium sulfide gives thiazolo3,2-f]xanthines whereas the reaction with secondary amines opens the oxazole ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1396–1399, October, 1990.