| abstract |
A compound of formula (I):n in which Y is chlorine, bromine or iodine, each of R 1 and R 2 is hydrogen or a group of formulan in which R 4 is hydrogen, optionally halo-substituted C 1-6 alkyl, phenyl or phenyl -C 1-6 alkyl, R 5 is optionally halo-substituted C 1-6 alkyl, or phenyl-C 1-6 alkyl, or R 4 and R 5 complete a ring system and together represent -(CH 2 ) 3 -, -(CH 2 ) 4 - or -CH 2 OCH 2 CH 2 -, and R 3 is hydrogen or an acyl group of formulan in which X is C 1-6 alkyl, phenyl or phenyl-C 1-8 alkyl, each of which is optionally substituted with halogen, with the proviso that R 1 and R 2 are not simultaneously hydrogen, is useful in treating viral infections. |