Purines, pyrimidines and imidazoles. Part 67. Some N-substituted o-(2-hydroxyethyl)benzyl-purines, -pyrimidines and -imidazoles as aromatic acylonucleoside analogues

Abstract

Reaction of isochromane with hydrogen bromide in acetic acid and further reaction of the products formed with potassium phthalimide gave a mixture of N-[o-(2-bromoethyl)benzyl]phthalimide and N-[o-(2-acetoxyethyl)benzyl]phthalimide. The mixture, on reaction with silver acetate, gave the latter compound, which with hydrazine gave o-(2-hydroxyethyl)benzylamine. The amine, on reaction with 2-cyano-2-(ethoxymethylenamino)acetamide, gave 5-amino-1-[o-(2-hydroxyethyl)benzyl] imidazole-4-carboxamide, which was cyclised to 9-[o-(2-hydroxyethyl) benzyl]-guanine, -hypoxanthine and -adenine. With N-ethoxycarbonyl-3-methoxy-2-methylacrylamide, 3-methoxy-2-methylacryloyl isothiocyanate and ethoxymethylenemalonyl urethane, the amine produced 1-[o-(2-hydroxyethyl)benzyl]thymine, -2-thiothymine and -N-ethoxycarbonyluracil-5-carboxamide respectively. The latter, on reaction with alkali, gave 1-[o-(2-hydroxyethyl)benzyl]uracil-5-carboxylic acid, which was decarboxylated to 1-[o-(2-hydroxyethyl)benzyl]uracil. Structures were confirmed by El, FAB and ¹H NMR spectra.