Synfacts 2010(12): 1327-1327  
DOI: 10.1055/s-0030-1258872
Synthesis of Natural Products and Potential Drugs
© Georg Thieme Verlag Stuttgart ˙ New York

Synthesis of (R)-Ofloxacin

Contributor(s):Philip Kocienski
M. Rueping*, M. Stoeckel, E. Sugiono, T. Theissmann
RWTH Aachen and Sanofi-Aventis Deutschland GmbH, Frankfurt am Main, Germany
Asymmetric Metal-Free Synthesis of Fluoroquinolones by Organocatalytic Hydrogenation
Tetrahedron  2010,  66:  6565-6568  
Further Information

Publication History

Publication Date:
22 November 2010 (online)


Significance

The key step in the small-scale synthesis of (R)-ofloxacin depicted here is the first step, a chiral Brønsted acid catalyzed transfer ­hydrogenation in which the hydride source is the dihydropyridine C. These reactions give excellent enantiofacial discrimination with low catalyst loadings under mild conditions. A synthesis of the simpler fluoroquinolone antibiotic flumequine is also described.

Comment

Ofloxacin is a DNA gyrase inhibitor that was initially marketed as a racemate. The (S)-(-)-enantiomer, levofloxicin, is more active than the (R)-enantiomer and has now supplanted the racemate for the treatment of life-threatening bacterial infections.

Review: For a review about asymmetric Brønsted acid catalyzed transfer hydrogenations, see: M. Rueping, E. Sugiono, F. R. Schoepke Synlett 2010, 852-865.