Process for producing 5-amino-8-alkylquinolonecarboxylic acid derivative and intermediates in the production thereof

摘要

The present invention provides a process for producing intermediates of antibacterial agents in accordance with the following steps and intermediates in the production thereof. (wherein R1: hydrogen atom or nitro group; R2: an alkyl group having 1 to 6 carbon atoms; R3, R4: an alkyl group having 1 to 6 carbon atoms or may form a 5-membered or 6-membered cyclic structure in combination with the nitrogen atom to which they are bonded, and the cyclic structure may contain oxygen atom, nitrogen atom, sulfinyl group, or sulfonyl group as a ring-constituting element; R6: a halogenocycloalkyl group having 3 to 6 carbon atoms; X1 represents a halogen atom or hydrogen atom; X2, X3: a leaving group; and Y: an alkyl group having 1 to 6 carbon atoms or an alkenyl group having 2 to 6 carbon atoms)