[structure: see text] 2-Aryl-2,2-difluoroacetamido-proline and pipecolate esters are high affinity FKBP12 ligands whose rotamase inhibitory activity is comparable to that seen for the corresponding ketoamides. X-ray structural studies suggest that the fluorine atoms participate in discrete interactions with the Phe36 phenyl ring and the Tyr26 hydroxyl group, with the latter resembling a moderate-to-weak hydrogen bond.

No abstract

No abstract

An efficient scale-up synthesis of (S)-5-chloro-1-(1-cyclopropylethyl)-3-(2,6-dichloro-4-(difluoromethoxy)phenylamino)-pyrazin-2(1H)-one, 1 (BMS-665053), is described. This new process features a one-step direct bis-orthochlorination of 4-(difluoromethoxy)aniline with HCl and H 2 O 2 , and a palladium-catalyzed coupling of 2,6-dichloro-4-(difluoromethoxy)aniline 2 and (S)-3,5-dichloro-1-(1-cyclopropylethyl)pyrazin-2(1H)-one 3. The process was applied to the preparation of batches of 1 for preclinical toxicology studies.

No abstract