Heterocycles h-Fused Onto 4-Oxoquinoline-3-Carboxylic Acid Part VIII 1. Convenient Synthesis and Antimicrobial Properties of Substituted Hexahydro14diazepino23-hquinoline-9-carboxylic acid and Its Tetrahydroquino78-bbenzodiazepine Analog

摘要

[1,4]Diazepino[2,3-h]quinolone carboxylic acid >3 and its benzo-homolog tetrahydroquino[7,8-b]benzodiazepine-3-carboxylic acid >5 were prepared via PPA-catalyzed thermal lactamization of the respective 8-amino-7-substituted-1,4-dihydro-quinoline-3-carboxylic acid derivatives >8, >10. The latter compounds were obtained by reduction of their 8-nitro-7-substituted-1,4-dihydroquinoline-3-carboxylic acid precursors >7, >9 which, in turn, were prepared by reaction of 7-chloro-1-cyclopropyl-6-fluoro-8-nitro-1,4-dihydroquinoline-3-carboxylic acid (>6) with each of β-alanine and anthranilic acid. All intermediates and target compounds were characterized using elemental analysis, NMR, IR and MS spectral data. The prepared targets and the intermediates have shown interesting antibacterial activity mainly against Gram positive strains. In particular, compound >8 showed good activity against S. aureus (MIC = 0.39 µg/mL) and B. subtilis (MIC = 0.78 µg/mL). Compounds >5a and >9 have also displayed good antifungal activity against C. albicans (MIC = 1.56 µg/mL and 0.78 µg/mL, respectively). None of the compounds tested showed any anticancer activity against solid breast cancer cell line MCF-7 cells or a human breast adenocarcinoma cell line.