Quinoline 3-carboxylate

Quinoline-3-carboxylic acid, l-methyl-6-nitro-4-oxo-antibacterial activity, 1, 180 Quinoline-3-carboxylic acid, 2-oxo-3-substituted... 

Friedlander synthesis, 2, 445 Quinoline-3-carboxylic acid, 4-oxo-synthesis... 

Ozonolysis of 5,8,9-trihydroxy-2,3-dihydro-l//-pyrimido[l, 2-n]quinoline-3-carboxylic acid (420), obtained from isopyoverdin isolated from Pseudomonas putida BTPl by acidic hydrolysis, gave l-2,4-diaminobutyric acid, which confirmed the hypothesis that heterocyclic chromophores 1 and 4 of pyoverdin and isopyoverdin, respectively, could have the same precursor, and the configuration at C(3) should be 5 (97ZN(C)549). 

ZN(C)153, 00ZN(C)323, 00ZN(C)857, 01MI2, 01MIP4, 01TL5849). 5-Amino-8,9-dihydroxy-2,3-dihydro-l//-pyrimido[l,2-u]quinoline-3-carboxylic acid moiety 4 was also identified as a chromophoric moiety of certain... 

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). 

Chamical Name l ethyl-1,4-dihydro-4-oxo-1,3-dioxolo[4,5-g] quinoline-3-carboxylic acid Common Name ... 

Bromo-3(6)-methyl-7-oxo-2,3-dihydro-7//-pyrido[l,2,3- 5 ]-l,4-benzoxazine-6-carboxylate 380 (R= H, R1 =Br) was obtained by cyclization of quinoline-3-carboxylate 379 (R = H, R1 Br) (Scheme 33) <2000WO00/046223>. (l,4-Benzoxazin-4-yl)methylenemalonate 381 was cyclized using PPA <1998MI828, 1998MIP1181381,... 

In the reactions of equimolar amounts of 3,4-diisobutoxyaniline, diethyl malonate, and ethyl imidate hydrochlorides in the presence of triethyla-mine at 120°C for 2 hr and then at 140°C for 15 hr, 2-substituted quinoline-3-carboxylates (269) were prepared (73ACH217). 

Substituted anilines were reacted with EMME in diphenyl ether by heating to 185°C, with distillation of the ethanol formed. The temperature of the reaction mixture was then raised to 245°C and the reaction mixture was heated at 245°C for 1 hr to give ethyl 6-substituted quinoline-3-carboxylates in good yields (85USP4560692). 

It was later claimed that the thermal cyclization of bis(aminomethylene-malonates) (601, R = H, Me, Cl, N02, R1 = Et) by heating in refluxing diphenyl ether for 15-30 min under nitrogen afforded 8-(substituted amino)quinoline-3-carboxylates (603) in 31-75% yields (78USP4123536). In the cases of the methyl and chloro derivatives (601, R = Me, Cl, R1 = Et), l,10-phenanthroline-3,8-dicarboxylates (602, R = Me, Cl, R1 = Et) could also be isolated as byproducts in 3-4% yields. 

Isomeric 2,3-dihydrofuro[3,2-/i]quinoline-7-carboxylate and 8,9-dihy-drofuro[2,3-/i]quinoline-3-carboxylate (615, X = CH2, Y = OandX = O,... 

N-( 1,3-Dioxoisoindol-4-yl)aminomethylenemalonate (623) was cyclized to pyrrolo[3,4-/i]quinoline-3-carboxylate (624) by heating in Dowtherm A (87MI1). 

The thermal ring closure of N-( 1,2,3,4-tetrahydrodibenzofuran-8-yl)-aminomethylenemalonate (664) in boiling Dowtherm A for 30 min afforded 7,8,9,10-tetrahydrobenzofuro[3,2-/i]quinoline-3-carboxylate (665) in good yield (69GEP1908542 70GEP2021100 71BRP1240446). 

The cyclization of Af-(bromophenyI)aminomethylenemalonates (684, R = H, R1 = Br) in a mixture of acetic acid and concentrated sulfuric acid afforded quinoline-3-carboxylic acids in poor yields due to the decomposition of the starting A-(bromophenyl)aminomethylenemalonates (78JIC193). 

Arylamino)quinoline-3-carboxylates (693) were prepared by the cyclization of /V -aryl(arylamino)methylenemalonamates (252) on the action of phosphoryl chloride in boiling benzene or of phosphorus pentoxide in refluxing xylene (46JA1246). Phosphoryl chloride proved to be a more effective cyclization agent than phosphorus pentoxide. This method could not be applied for the preparation of 4-alkylaminoquinoline-5-carbox-ylates. 

Markees and Schwab cyclized A-alkyl-Af-arylaminomethylenemal-onates (106, R3 = H) by treatment with phosphorus pentoxide (72HCA1319). Equal amounts of aminomethylenemalonates (106, R3 = H) and phosphorus pentoxide were warmed to about 130°C, when exothermic reactions occurred. The temperature of the reaction mixtures rose to about 190°C. After the work-up process, quinoline-3-carboxylic acids (696) were obtained in 41-63% yields. Better yields (76-96%) were achieved when the reactions were carried out in nitrobenzene. 

The cyclization of arylaminomethylenemalonates (701) on the action of phosphorus pentoxide in nitrobenzene gave quinoline-3-carboxylates (702) in 16-85% yields (74JMC137). Polyphosphoric acid proved to be a more effective cyclization agent than the phosphorus pentoxide-nitrobenzene system. For example, a chloro derivative (701, R = Et, R1 = Cl, R2 = R3 = R4 = H) gave quinoline-3-carboxylate (702, R = Et, R1 = Cl, R2 = R3 = R4 = H) in 46% yield on the action of polyphosphoric acid, whereas the yield was only 16% in the phosphorus pentoxide-nitrobenzene system. 

Af-Ethyl-A-(3-halo-2-methylphenyl)aminomethylenemalonates (106, R = Et, R1 = Me, R2 = Hlg, R3 = H) were heated in polyphosphoric acid, prepared from phosphoric acid and phosphorus pentoxide, at 140°C for 40 min. The reaction mixture was then poured into water, and the product was hydrolyzed with 10% aqueous sodium hydroxide to give quinoline-3-carboxylic acids (696, R = Et, R1 = Me,R2 = Hlg) in 68-70% yields (80GEP3007006). 

The cyclization of /V-(2-substituted 3,4-difluorophenyl)aminometh-ylenemalonate (734) in polyphosphate at 100°C for 10 hr under nitrogen gave the quinoline-3-carboxylic acid (735) after work-up of the reaction mixture (87EUP216345). 

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