Structure-activity relationship in the 3-iodo-4-phenoxypyridinone (IOPY) series: the nature of the C-3 substituent on anti-HIV activity

As part of a systematic SAR study on the 3-iodo-4-phenoxypyridinone 3 (IOPY) type non-nucleoside reverse transcriptase inhibitors, the analogues 4a-4z bearing different C-3 substituents were synthesized and evaluated for their anti-HIV activity against wild-type HIV-1 and four of the principal HIV mutant strains (K103N, Y181C, Y188L, and I100L). The results show that the 3-vinyl analogue 4j is the only compound which displays anti-HIV activity comparable to IOPY 3, and in this respect represents a possible back-up to this lead molecule

Crystal structures for HIV-1 reverse transcriptase in complexes with three pyridinone derivatives: a new class of non-nucleoside inhibitors effective against a broad range of drug-resistant strains

In the treatment of AIDS, the efficacy of all drugs, including non-nucleoside inhibitors (NNRTIs) of HIV-1 reverse transcriptase (RT), has been limited by the rapid appearance of drug-resistant viruses. Lys103Asn, Tyr181Cys, and Tyr188Leu are some of the most common RT mutations that cause resistance to NNRTIs in the clinic. We report X-ray crystal structures for RT complexed with three different pyridinone derivatives, R157208, R165481, and R221239, at 2.95, 2.9, and 2.43 A resolution, respectively. All three ligands exhibit nanomolar or subnanomolar inhibitory activity against wild-type RT, but varying activities against drug-resistant mutants. R165481 and R221239 differ from most NNRTIs in that binding does not involve significant contacts with Tyr181. These compounds strongly inhibit wild-type HIV-1 RT and drug-resistant variants, including Tyr181Cys and Lys103Asn RT. These properties result in part from an iodine atom on the pyridinone ring of both inhibitors that interacts with the main-chain carbonyl oxygen of Tyr188. An acrylonitrile substituent on R165481 substantially improves the activity of the compound against wild-type RT (and several mutants) and provides a way to generate novel inhibitors that could interact with conserved elements of HIV-1 RT at the polymerase catalytic site. In R221239, there is a flexible linker to a furan ring that permits interactions with Val106, Phe227, and Pro236. These contacts appear to enhance the inhibitory activity of R221239 against the HIV-1 strains that carry the Val106Ala, Tyr188Leu, and Phe227Cys mutations.status: publishe