Chiral Pool Synthesis, Biological Evaluation and Molecular Docking Studies of C-Furanosidic LpxC Inhibitors

Abstract

Inhibitors of the bacterial deacetylase LpxC are a promising class of novel antibiotics, being selectively active against Gram-negative bacteria. To improve the biological activity of reported C-furanosidic LpxC inhibitors, the stereochemistry at positions 3 and 4 of the tetrahydrofuran ring was varied. In chiral pool syntheses starting from d-gulono-γ-lactone and d-ribose, a series of (3S,4R)-configured dihydroxytetrahydrofuran derivatives was obtained, of which the (2S,5S)-configured hydroxamic acid 15 ((2S,3S,4R,5S)-N,3,4-trihydroxy-5-(4-{[4-(morpholinomethyl)phenyl]ethynyl}phenyl)tetrahydrofuran-2-carboxamide) was found to be the most potent LpxC inhibitor (K_i =0.4 μm), exhibiting the highest antibacterial activity against E. coli BL21 (DE3) and the D22 strain. Additionally, molecular docking studies were performed to rationalize the obtained structure-activity relationships.

Keywords: C-glycosides; LpxC inhibitors; antibiotics; conformational restriction; molecular docking studies.