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Research has been conducted on the arabinonucleic acid (ANA) which is the 2'-epimer of RNA. The synthesis of the ANA from the arabinonucleoside building blocks is described.

A study was conducted to analyze the biochemical and physiochemical features of 2'5'-linked oligoribonucleotides characterized by mixed sequences of the four nucleobases. A Protein Pak DEAE-5PW column was utilized to purify sequences by anion-exchange while ultraviolet thermal denaturation values were determined on a Varian CARY 1 spectrophotometer. Results showed that 2',5'-linked oligoribonucleotides of mixed base composition associate selectively to complementary single-stranded RNA but not to DNA.

The efficiency of N-(4-tert-butylbenzoyl)-2-hydroxy-1-naphthaldehyde hydrazone (BBNH) in inhibiting the catalytic activity of HIV-1 reverse transcriptase (RT) was analyzed during HIV-1 replication in vitro. The administration of BBNH inhibited the RNA-dependent DNA polymerase, DNA-dependent DNA polymerase and ribonuclease H activities of HIV-1 RT in vitro. Furthermore, non-nucleoside inhibitor-resistant mutant HIV-1 RT activity and viral replication in infected cells were also inhibited by the hydrazone.

The combination of UC38 and UC84 shows a high degree of synergy in inhibiting HIV-1 replication in both MT-4 and cord mononuclear cells and are the first example of synergistic inhibition of HIV-1 RT by combinations of nonnucleoside inhibitors. This effect is noted primarily in reactions containing high concentrations of primer/template and Km levels of dNTP substrate and is independent of both primer/template identity and the molar ratio of UC84:UC38. A notable synergy in the inhibition of RT activity is indicated by the combination indices which are in the range of 0.4-0.6.

A comparison was made between the wild-type reverse transcriptase (RT) with the D67N/K70R/T215F/K219Q, D67N/K70R and T215F/K219Q mutant enzymes. It was observed that the D67N/K70R/T215K/K219Q mutant RT had increased DNA polymerase processivity associated with a decreased template/primer dissociation rate. The processivity of pyrophosphorolysis was identical for the wild-type and mutant enzymes. The enhanced pyrophosphorolytic rate of the mutant RT resulted in the removal of chain-terminating 3'-deoxynucleotides, allowing additional DNA chain elongation.