Interaction of oligonucleotides conjugated to substituted chromones and coumarins with HIV-1 reverse transcriptase

Ten different pyranone-related substituents (chromones or coumarins) were c ovalently linked to the 5' end of various oligonucleotides (ODN), The inter action of these compounds with human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) was analyzed, A different behavior was found to depend on the structure of the olgonucleotide derivatives. Some compounds a ctivated the enzyme at relatively low concentrations (0.1-0.5 mu M), follow ed by an inhibition of the activity at higher concentrations (5-20 mu M), w hereas others behave just as inhibitors. Because the presence of some couma rin or chromone derivatives conjugated to ODNs enhanced the interaction wit h the reverse transcriptase, we analyzed the capacity of such ODN derivativ es to be used as primers. The introduction of substituent I, a chromone der ivative, the 2-[(3-(aminopropyl)amino]-8-isopropyl-5-methyl-4-oxo-4H-1-benz opyran-3-carbaldehyde], and II, a coumarin derivative, the 1-(3-aminopropox y)-2-ethyl-3H-naphto[2,1-b]pyran-3-one into the 5' end of a noncomplementar y ODN allowed these compounds to be used as primers. In the case of complem entary primers, the presence of conjugated derivatives enhanced the affinit y with K-m values that were two to three orders of magnitude lower than tha t of a complementary primer of the same length. After addition of a ddT-uni t to the 3'-terminal end of the ODN, some of these primers became very effe ctive inhibitors of RT with Ki values in the nanomolar range.