Chemoenzymatic Synthesis of Tenofovir

J Org Chem. 2023 Aug 4;88(15):11045-11055. doi: 10.1021/acs.joc.3c01005. Epub 2023 Jul 19.

Abstract

We report on novel chemoenzymatic routes toward tenofovir using low-cost starting materials and commercial or homemade enzyme preparations as biocatalysts. The biocatalytic key step was accomplished either via stereoselective reduction using an alcohol dehydrogenase or via kinetic resolution using a lipase. By employing a suspension of immobilized lipase from Burkholderia cepacia (Amano PS-IM) in a mixture of vinyl acetate and toluene, the desired (R)-ester (99% ee) was obtained on a 500 mg scale (60 mM) in 47% yield. Alternatively, stereoselective reduction of 1-(6-chloro-9H-purin-9-yl) propan-2-one (84 mg, 100 mM) catalyzed by lyophilized E. coli cells harboring recombinant alcohol dehydrogenase (ADH) from Lactobacillus kefir (E. coli/Lk-ADH Prince) allowed one to reach quantitative conversion, 86% yield and excellent optical purity (>99% ee) of the corresponding (R)-alcohol. The key (R)-intermediate was transformed into tenofovir through "one-pot" aminolysis-hydrolysis of (R)-acetate in NH3-saturated methanol, alkylation of the resulting (R)-alcohol with tosylated diethyl(hydroxymethyl) phosphonate, and bromotrimethylsilane (TMSBr)-mediated cleavage of the formed phosphonate ester into the free phosphonic acid. The elaborated enzymatic strategy could be applicable in the asymmetric synthesis of tenofovir prodrug derivatives, including 5'-disoproxil fumarate (TDF, Viread) and 5'-alafenamide (TAF, Vemlidy). The molecular basis of the stereoselectivity of the employed ADHs was revealed by molecular docking studies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alanine
  • Alcohol Dehydrogenase
  • Anti-HIV Agents*
  • Escherichia coli
  • Lipase
  • Molecular Docking Simulation
  • Organophosphonates*
  • Tenofovir

Substances

  • Tenofovir
  • Alcohol Dehydrogenase
  • Alanine
  • Organophosphonates
  • Lipase
  • Anti-HIV Agents