名称:
2′,3′-Dideoxynucleoside 5′-β,γ-(Difluoromethylene) Triphosphates With α-P-Thio or α-P-Seleno Modifications: Synthesis and Their Inhibition of HIV-1 Reverse Transcriptase
摘要:
Nucleoside reverse transcriptase inhibitors (NRTIs) are prodrugs which require three intracellular phosphorylation steps to yield their corresponding, biologically active, nucleoside triphosphate. In order to circumvent this often inefficient phosphorylation cascade, a plausible approach is to provide the active species directly in the form of a stabilized nucleoside triphosphate mimic. We have previously shown that such a mimic, namely 5'-alpha-R-p-borano-beta,gamma-(difluoromethylene) triphosphate (5'-alpha BCF2TP) is a generic triphosphate mimic that is biologically stable and can render antiviral ddNs with potent inhibitory activity against HIV-1 RT.([1,2]) Herein we report the synthesis and activity against HIV-1 RT of several ddN 5'-alpha-modified-beta,gamma-(difluoromethylene) triphosphate mimics with either a non-bridging alpha-P-thio (5'-alpha SCF2TP) or alpha-P-seleno (5'-alpha SeCF2TP) modification. One compound, namely, AZT-5'-alpha-P-seleno-beta,gamma-(difluoromethylene) triphosphate (diastereomer I), was identified as a potent inhibitor of HIV-1 RT (K-i = 64 nM) and represents the first report of HIV-1 RT inhibition data for a nucleotide bearing an alpha-P-seleno modification. These triphosphate mimics may be useful in the investigation of enzyme mechanism and may have interesting properties with respect to drug resistance and polymerase selectivity.