Purine studies. Part IV. A search for covalent hydration in 8-substituted purines

Abstract

The following purines, with electron-attracting substituents in the 8-position, have been prepared and examined for covalent hydration: 2-amino- and 2-hydroxy-8-trifluoromethyl-, 8-methylsulphonyl-, 2-amino- and 2-hydroxy-8-methylthio-, 2,8-bismethylthio-, and 2-amino-8-methylsulphonyl-purine. No evidence of covalent hydration could be found. Ionisation constants, ultraviolet spectra, and stability data are presented for several purines and 4-amino-5-acylaminopyrimidines.