Oxazolo quinoline-8-carboxylate

C13H11CIN2O2 f 3-(p-Chlorophenyl)-6-methyl-2-oxo-2,3,3a,7a-tetrahyd-ro-oxazolo[4,5-b]pyridine, 45B, 403 Cl3H11CIN2O2, 3-(p-Chlorophenyl)-7a-methyl-2-oxo-2,3,3a,7a-tetrahyd-ro-oxazolo[4,5-b]pyridine, 45B, 403 C13H12N2O5, 1-Ethyl-1,4-dihydro-4-oxo-5-amino-6,7-methylenedioxy-3-quinoline-carboxylic acid, 42B, 277 C13H13CIN2O3S, 1-p-Chlorophenyl-4-(a-D-erythrofuranosyl)-4-imidazo-line-2-thione, 40B, 332... 

Chloro-oxazolo[4,5-/i]quinoline-2-carboxylic acid methyl ester was the most active compound in tests for inhibitors of antigen-induced release of histamine in vitro from rat peritoneal mast cells (IC50 of 0.3 p,M) and as inhibitors of IgE-mediated passive cutaneous anaphylaxis in the rat (ED50 (intraperitoneal) of 0.1 mg/kg in dose 0.5 mg/kg as an inhibitor of the test)—10 times and 60 times more potent, respectively, than the disodium salt of cromoglycic acid (85JMC1255). 

Several 7-substituted (H, halogen, alkoxy, alkylthio, halogen, alkyl, carboxyl) oxazolo[5,4-/i]quinolines were found to be very effective against broadleaf weeds (90EUP1, 90GEP1). 

Thermal cyclization of the arylaminomethylenemalonate afforded quinoline 3-carboxylate 630 whose reaction with 1,1-dibromoethane gave oxazolo[5,4,3-(/]quinoline 631. Acid hydrolysis and reaction with N-methylpiperazine gave 632 whose bactericidal activity is superior to that of pipemidic acid (82JAPK57203085) (Scheme 108). 

Substituted oxazolo[4,5-Z ]pyridines 138 (and quinolines) were synthesised in high yields from zwitterion or hydroxyamidine derivatives 137, obtained by treatment of non-enolisable amides 136 with the complex base NaNH2-/-BuONa, via hetaryne intermediates. Intramolecular cyclization and NH3 elimination to give 138 were performed in dimethylacetamide by heating or microwave irradiation <03S2033>. Different approaches to oxazolo[4,5-c]quinoline-4(5/f)-ones from ethyl 2-chlorooxazole-4-carboxylate have also been described <03OL2911>. 

Oxazolo[3,2-a]quinolinium, 2-methyl-13C NMR, 6, 652 (67JHC66) lH,3H-Oxazolo[4,3-c][l,4]thiazine-6-carboxylic acid 7-oxide, 8,8a-dihydro-3,3-dimethyl-, methyl ester X-ray, 6, 647 (74JCS(P2)1132) lH,3H,5/f-Oxazolo[3,4-a]quinoline, 1-substituted X-ray, 6, 646 <79JCS(P1)1013>... 

---