The subject invention relates to pyrimidine-thioalkyl and alkylether compounds of Formula (I) and pyrimidine-thioalkyl and alkylethers of Formula (IA), namely the compounds of Formula (I) where R.sup.4 is selected from the group consisting of --H or --NR.sub.15 R.sub.16 where R.sub.15 is --H and R.sub.16 is --H, C.sub.1 -C.sub.6 alkyl, --NH.sub.2 or R.sub.15 and R.sub.16 taken together with the --N form 1-pyrrolidino, 1-morpholino or 1-piperidino; and R.sub.6 is selected from the group consisting of --H, or halo (preferably --Cl); with the overall proviso that R.sub.4 and R.sub.6 are not both --H. The compounds of Formula (IA) are useful in the treatment of individuals who are HIV positive.