Design and stereoselective synthesis of a C-aryl furanoside as a conformationally constrained CHIR-090 analogue

The UDP-3-O-[(R)-3-hydroxymyristoyl]-N-acetylglucosamine deacetylase (LpxC) is a promising target for the development of novel antibiotic substances against multidrug-resistant Gram-negative bacteria. The C-aryl glycoside 3 was designed as conformationally constrained analogue of the potent LpxC-inhibitor CHIR-090. The chiral pool synthesis of 3 started with D-mannose. The C-aryl glycoside 8 was synthesized stereoselectively by nucleophilic attack of 4-iodine-substituted phenyllithium and subsequent reduction with Et(3)SiH. The ester 10 was obtained in a one-pot diol cleavage, CrO(3) oxidation, and esterification. A Sonogashira reaction of the aryl iodide 11 led to the alkyne 17 which was transformed with H(2)NOH into the hydroxamic acid 3.