Crystal structure of tert-butyldimethylsilyl-spiroaminooxathioledioxide-thymine (TSAO-T) in complex with HIV-1 reverse transcriptase (RT) redefines the elastic limits of the non-nucleoside inhibitor-binding pocket

tert-Butyldimethylsilyl-spiroaminooxathioledioxide (TSAO) compounds have an embedded thymidine-analogue backbone; however, TSAO compounds invoke non-nucleoside RT inhibitor (NNRTI) resistance mutations. Our crystal structure of RT:7 (TSAO-T) complex shows that 7 binds inside the NNRTI-binding pocket, assuming a "dragon" shape, and interacts extensively with almost all the pocket residues. The structure also explains the structure-activity relationships and resistance data for TSAO compounds. The binding of 7 causes hyper-expansion of the pocket and significant rearrangement of RT subdomains. This nonoptimal complex formation is apparently responsible (1) for the lower stability of a RT (p66/p51) dimer and (2) for the lower potency of 7 despite of its extensive interactions with RT. However, the HIV-1 RT:7 structure reveals novel design features such as (1) interactions with the conserved Tyr183 from the YMDD-motif and (2) a possible way for an NNRTI to reach the polymerase active site that may be exploited in designing new NNRTIs.     

Design,synthesis and activity evaluation of novel pyridinone derivatives as anti-HIV-1 dual (RT/IN) inhibitors

Three series of novel anti-immunodeficiency virus 1 (HIV-1) dual (RT/IN) inhibitors were rationally designed by introducing a functioning diketo acid (DKA) into pyridin-2-one scaffold. To efficiently analyze inhibitory activity, these compounds were screened against HIV-1 RT and IN respectively via surface plasmon resonance (SPR), and active compounds were subsequently evaluated by enzyme assay. It was noteworthy that compound A2 exhibited moderate activity against both HIV-1 RT and IN. This result provided information for further development of pyridinone analogues as potent dual HIV-1 inhibitors.