A new class of dihaloquinolones bearing N'-aldehydoglycosylhydrazides, mercapto-1,2,4-triazole, oxadiazoline and a-amino ester precursors: synthesis and antimicrobial activity

Abstract

A reação das quinolonas 6-8 com hidrazina forneceu as hidrazidas 9-11 em rendimentos moderados. A condensação de 9 e 11 com CS 2 /KOH rendeu os sais de potássio 13 e 14, respectivamente, que espontaneamente forneceram as 3-(1,2,4-triazolil)-quinolonas 15 e 16, respectivamente, quando tratadas com hidrazina. A reação de 9 com CS 2 /KOH sob refluxo resultou na 3-(1,2,4-oxadiazolil)-quinolona 17. Alternativamente, 15 foi preparado a partir de 17. O derivado 12, obtido a partir de 10, forneceu o derivado α-amino ester 18 mediante reação com o éster etílico da glicina. O acoplamento de 10 com vários açúcares forneceu as N'-(aldeidoglicosil-quinolona-3-il)carbohidrazidas 19a-e. Os novos compostos sintetizados foram avaliados quanto a sua atividade antibacteriana.Reaction of the quinolones 6-8 with hydrazine afforded the hydrazide 9-11 in moderate yields. Condensation of 9 and 11 with CS 2 /KOH furnished the potassium salts 13 and 14, respectively, which spontaneously afforded the 3-(1,2,4-triazolyl)-quinolones 15 and 16, respectively, on treatment with hydrazine. Reaction of 9 in refluxing CS 2 /KOH gave the 3-(1,2,4-oxadiazolyl)-quinolone 17. Alternatively, 15 was prepared from 17. The azide derivative 12, obtained from 10, furnished the α-amino ester derivative 18, on reaction with the glycine ethyl ester. Coupling of 10 with various sugars gave the N'-aldehydoglycosyl-quinolone-3-yl)carbohydrazides 19a-e. The newly synthesized compounds were screened for their antibacterial activity.

Ciprofloxacin-Induced Antibacterial Activity is Reversed by Vitamin E and Vitamin C

“…Ciprofloxacin, on the other hand, is a second generation fluoroquinolone antibiotics that is active against both Gram-positive and Gram-negative bacteria. Ciprofloxacin is widely used in treatment of several infections including urinary tract infections, acute uncomplicated cystitis, chronic bacterial prostatitis, and acute sinusitis [2].…”

Syntheses and antibacterial studies of some 2-[5-(Aryl)-[1,3,4]oxadiazole-2-ylsulfanyl] alkanoic Acids

“…1,3,4-Oxadiazole derivatives constitute an important class of heterocycles possessing diverse biological activities like antibacterial [1][2][3][4], fungitoxic [5,6], insecticidal [7], herbicidal [8], anticancer [9], anti-inflammatory [10] etc. Further, [5-(aryl)-1,3,4-thiadiazole-2-ylthio]acetates and propionates have been found to possess antimycobacterial activity [11][12][13][14].…”

Microwave‐assisted synthesis and anti‐HIV activity of new benzenesulfonamides bearing 2,5‐disubstituted‐1,3,4‐oxadiazole moiety

“…The potassium salts of 3-[2-(4-methyl/chloro or methoxyphenylsulfonamido)]alkyl dithiocarbazinates 2 were prepared by reaction of the hydrazides 1 with CS 2 in alcoholic KOH [21].…”