A novel series of tetracyclic quinobenzothiazine derivatives was synthetized. Compounds containing a substituent (hydroxyl, methyl, phenyl, piperidyl, or piperazinyl) in positions 9 and 11 were obtained by cyclization of suitable 4-aminoquinolinium-3-thiolates. Quinobenzothiazine 10-O-substituted derivatives were obtained by alkylating the hydroxyl group in position 10 of the parent (quinobenzo...

7-{2-Hydroxy-3-[4-(2-phenoxyethyl)-piperazinyl-1-yl]-propyl}-1,3-di-methyl-3,7-dihydro-1H-purine-2,6-dione dihydrochloride (2), and several of its 8-alkylamino substituted derivatives (11-17) were synthesized and tested for electrocardiographic, antiarrhythmic and hypotensive activity. Also their alpha(1)- and alpha(2)-adrenoreceptor affinities were determined. It was found that compound 2, and...

Gatifloxacin is a recently marketed quinolone with an enhanced activity against gram-positive bacteria compared with that of ciprofloxacin (4, 12, 13, 18). The structural differences between gatifloxacin and ciprofloxacin are substituents at the C-8 position of the quinolone nucleus (gatifloxacin, C-8-methoxy; ciprofloxacin, C-8-H) and at the C-3 position of the piperazinyl moiety of the C-7 po...

conclusions ctx-m was the most prevalent esbl genotype in uropathogenic e. coli (upec) isolated from uti. in addition, a high frequency of qnr genes among esbl-producing e. coli was identified in this study. in order to avoid treatment failures, we recommend using phenotypic and molecular methods to diagnose these enzymes and qnr genes. results the highest sensitivity was seen to imipenem (96.7...

A number of fluoroquinolone derivatives were synthesized and evaluated for antimycobacterial activity. Preliminary results are (1) for 1-aryl fluoroquinolones, 1-(4-nitrophenyl) derivatives were inactive while their 1-(2-fluoro-4-nitrophenyl) counterparts were active anti-TB agents (3a vs 4a; 3b vs 4b) indicated the fluoro substituent at C-2 position is important. For the 1-(2-fluoro-4-nitrophe...

The excellent catalytic activity of newly magnetic nanocatalyst FeAl 2 O 4 @PTMS-sulfaguanidine-SA in a one pot multicomponent Mannich-type reaction was used to obtain 2-piperazinyl quinoxaline derivatives with highly selective anti-proliferation efficacy.

tetrahydroisoquinolines, 1,2,3,4-tetrahydroquinolines, 2,3,4,5-tetrahydro-1H-3-benzazepines, 2-quinolones, erythrinan, homoerythrinan, isopavine and pavine alkaloids using an aromatic cyclization of the sulfonium ion in situ formed from a sulfinyl precursor (Pummerer reaction). The aromatic cyclization in the reaction using trifluoroacetic anhydride (TFAA) smoothly proceeded at room temperature...

OBJECTIVE Quinolone moiety is an important class of nitrogen containing heterocycles widely used as key building blocks for medicinal agents. It exhibits a wide spectrum of pharmacophores and has bactericidal, antiviral, antimalarial, and anticancer activities. In view of the reported antimicrobial activity of various fluoroquinolones, the importance of the C-7 substituents is that they exhibit...