The synthesis and in vitro anti-HIV activity of two new racemic nucleoside analogues are described; namely, 9-[c-4,t-5-bis(hydroxymethyl)cyclopent-2-en-r-1-yl]-9H-adenine (12) and its guanine analogue 18. While the latter (18) showed no activity, the therapeutic index of the former (12) was 200 and comparable to that (400) of carbovir. One enantiomer of 12 may be viewed as an analogue of carbocyclic oxetanocin and the other as an analogue of carbovir. Hence, these results indicate that one or both of the individual enantiomers of 12 could serve as candidates or lead compounds for the development of anti-AIDS agents.