1,8-Diazabicyclo(5.4.0)undec-7-ene → 1-Ethyl-6-fluoro-7-(3-methyl-3,8-diazaspiro[4.4]nonan-8-yl)-4-oxo-1,8-naphthyridine-3-carboxylic acid

Participants

Reaction Steps

A stirred suspension of 4.40 g (20.7 mmol) of 2-methyl-2,7-diazaspiro[4.4]nonane dihydrochloride in 200 ml acetonitrile was treated with 9.42 g (62 mmol) 1,8-diazabicyclo[5.4.0]undec-7-ene and 5.42 g (20 mmol) 1-ethyl-6-fluoro-7-chloro-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carboxylic acid was added. After stirring 23 hours at room temperature the precipitated product was filtered, washed with acetonitrile and ether, and recrystallized from ethanol to afford 3.99 g of the title compound, mp 252°-254° C. (dec).

Provenance & Evidence