Synthesis of the Bicyclic Secondary Amines via Dimethylaminomethylene Ketones from 3-Pyrrolidone and 4-Piperidone

Abstract

The reaction of N-protected 3-pyrrolidone and 4-piperidone with N,N-dimethylformamide dimethyl acetal gave the dimethylaminomethylene ketones, which reacted with several types of hydrazines, amidines, and guanidine to afford the secondary amines having fused ring system.Since the introduction of antibacterial fluoroquinolones in the early 1980s, this class of compounds have become one of the most attractive agents in the antiinfective chemotherapy field. 1 The cyclic amine side chain at the 7-position of the quinolone nucleus is known to be a very important part for its antibacterial activity, and many groups are still researching novel compounds with potent antibacterial activity. 2cently, moxifloxacin (Figure 1), having a bicyclic amine side chain at the 7-position of the quinolone nucleus, was reported to possess potent antibacterial activity, especially against Gram-positive bacteria including the drug resistant strains. 3We synthesized the secondary amines having a fused ring system using a simple procedure via the common intermediates as follows.N COOH O