| abstract |
Compounds of formula (I) <CHEM> wherein X is hydrogen, NRR<1>, SR, OR or halogen; Z is hydrogen, OR<2> or NRR<1>; R, R<1> and R<2> may be the same or different and are selected from hydrogen, C1-4alkyl and aryl; and pharmaceutically acceptable derivatives thereof show a synergistic antiviral effect when coadministered with one or more second antiviral compounds selected from 3 min -azido-3 min -deoxythymidine, ribavirin, 3 min -azido-2 min ,3 min -dideoxyuridine and 2 min ,3 min -dideoxy-2 min ,3 min -didehydrothymidine. Synergistic combinations of this type are especially useful in combating retroviruses, for example HIV. |