(S)-tert-Butyl 5-azaspiro[2.4]heptan-7-ylcarbamate → 7-[7-(S)-Amino-5-azaspiro[2.4]heptan-5-yl]-6-fluoro-1-[(1R,2S)-2-fluorocyclopropyl]-5-methyl-4-oxo-1,4-dihydroquinoline-3-carboxylic Acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 200 mg of 6,7-difluoro-1-[(1R,2S)-2-fluorocyclopropyl]-5-methyl-4-oxo-1,4-dihydroquinoline-3-carboxylic acid, 287 mg of 7-(S)-t-butoxycarbonylamino-5-azaspiro[2.4]heptane, and 5 ml of anhydrous dimethyl sulfoxide was heated at 100° C. for 30 minutes with stirring. After allowing to cool, the reaction mixture was concentrated under reduced pressure, and water was added to the residue. The precipitated yellow crystals were collected by filtration and added to 5 ml of trifluoroacetic acid while stirring and cooling with ice, followed by stirring at room temperature for 30 minutes. The reaction mixture was further worked up in the same manner as in Example 7. Recrystallization of the crude crystal from ethanol gave 122 mg of the titled compound as a pale yellow powder.

Provenance & Evidence