Chemistry and Biology of the Clinically Used Macrolactone Antibiotic Fidaxomicin

Fidaxomicin (1, lipiarmycin A3, clostomicin B1, tiacumicin B) constitutes a glycosylated 18-membered macrolactone and is a natural product isolated from various soil bacteria. Since 2011, fidaxomicin is a marketed antibiotic for the treatment of intestine infections caused by C. difficile in the clinic. Its promising in vitro antibacterial properties against resistant S. aureus and M. tuberculosis continue to attract interest. This review article describes the early history of the antibiotic fidaxomicin and highlights recent advances in the field, such as the elucidation of its mode of action and biosynthesis, as well as known derivatives. Furthermore, different synthetic strategies towards the total synthesis of fidaxomicin are summarized

Conformational study of glycal-type neuraminidase inhibitors

International audienceConformational study of glycal-type neuraminidase inhibitors The conformational flexibility of two glycal-type neuraminidase inhibitors has been studied, using several molecular modeling techniques. In agreement with the experimental data available, an intramolecular hydrogen bond, representing a key structural feature that controls the conformer distribution in solution, has been identified. The contribution of each substituent on the overall equilibrium was evaluated using simplified derivatives. Additionally, four methods for estimating NMR coupling constants from dihedral angles were evaluated and the Haasnoot method was found to be appropriate for this class of sugars. These results should allow a better understanding of the structural parameters governing physico-chemical properties of glycal-like compounds