Preparation, spectral properties and biological activities of 5-bromo-6-methyl-2'-deoxyuridine and 5-iodo-6-methyl-2'-deoxyuridine

Reaction of 3',5'-di-O-benzoyl-6-methyl-2'-deoxyuridine ( IIa ) with elementary bromine or iodine afforded 5-halogeno derivatives IIc and IId which on methanolysis gave 5-bromo-6-methyl-2'-deoxyurine ( Ic ) and 5-iodo-6-methyl-2'-deoxyurine ( Id ), respectively. The CD spectra of Ic, Id and 6-methyl-2'-deoxyuridine ( Ia ) are compared and discussed with regard to determination of the nucleoside conformation. Unlike 5-bromo- and 5-iodo-2'-deoxyuridine, the 6-methyl derivatives Ic and Id exhibit neither antibacterial nor antiviral activity. Nor do they exert any antimetabolic effect on the de novo DNA synthesis in primary rabbit kidney cells.