Quinoline-2-carboxylic acids 4-hydroxy

A mixture of 26 parts of 3-carbethoxy-6,7-methylenedioxy-4-hydroxy-quinoline, 16 parts of sodium hydroxide and 50 parts of dimethylformamide is heated at 70° to 75°C for 2 hours, then 31 parts of ethyl iodide is added over 1 hour with continued heating and stirring. After an additional 3 to 4 hours of heating (at 70° to 75°C) and stirring, the mixture is diluted with 500 parts of water, refluxed for 3 to 4 hours, acidified with concentrated hydrochloric acid and filtered to yield 18 to 22 parts of 1-ethyl-1,4-dihydro-6,7-methylene-dioxy-4-oxo-3-quinoline-carboxylic acid, MP 309° to 314°C (decomposes). The analytical sample from dimethylformamide melts at 314° to 316°C (decomposes). 

Ifenprodil (= l-Methyl-2-hydroxy-2-(4-hydroxyphenyl) ethyl-1 -(4-benzyl-piperidine)] -(aryl piperidine) [at(/o-3-(Indol-2-yl)-8-methyl-8-azabicyclo-[3.2.1] octane] (indolotropane) [Kynurenic acid (= 4-Hydroxy-2-quinolinecarboxylic acid)] (quinoline carboxylic acid) [Memantine (= 1-Amino-3,5 dimethyladamantane)] (amino adamantane, amino cyclic aliphatic) [Methadone (= 6-Dimethylamino-4,4-diphenyl-3-heptanone)] (aryl tertiary amine) [em/o-3-(l -Methylindol-2-yl)-8-methyl-8-azabicyclo-[3.2.1] octane(indolotropane) exo- 3-( 1 -Methylindol-2-yl)-8-methyl-8-... 

Figure 3. Biotransformation cascade of oxolinic acid in fish. A, oxolinic acid B., Glucuronide of oxolinic acid C., 7-hydroxy-6-methoxy derivative (1-ethyl-1,4 dihydro-7-hydroxy-6-methoxy-4-oxo-3-quinoline carboxylic acid) D., 6-hydroxy-7-methoxy derivative (1 -ethyl-1,4-dihydro-6-hydroxy-7-methoxy-4-oxo-3-quinoline-carboxylic acid. E,F. Stars represent unconfirmed sites of glucuronidation of 7-hydroxy-6-methoxy and 6-hydroxy-7-methoxy oxolinic acid derivatives.

Quinolobactin, 8-hydroxy-4-methoxy-2-quinoline carboxylic acid, is an alkaloid produced by Pseudomonas fluorescens ATCC17400. The biosynthesis of quinolobactin involves the tryptophan-kynurenine-xanthurenic acid pathway (Figure 6.13). 

Supplement 1953 3242-3457 Hydroxy-carboxylic acids, 190 In i doxylic acid, 226. Carbonyl-carboxylic acids, 284. i Sulphonic acids, 386 Quinoline sul-phonic acid, 390. Amines, 419 2-Aminopyridine, 428. Amino-carboxylic acids, 541 Tryp- tophane, 545. Hydrazines, 563. Azo. compounds, 572. Diazo compounds, 590. ... 

Quinoline-4-carboxylic acid, 3-hydroxy-Pfitzinger synthesis, 2, 446 Quinoline-4-carboxylic acid, 2-methyl-synthesis, 2, 475... 

Quinoline, 8-mercapto-2-methyl-metal complexes, 2, 800 Quinoline, 2-methyl-8-(methylthio)-metal complexes, 2,801 Quinoline, 8-methylthio-metal complexes, 2, 801 Quinoline-2-carboxylic-acid, 8-hydroxy-methyl ester... 

In the early days, greatest interest was focused on the acid-catalyzed hydrolysis (by hydrochloric acid in the presence of 2,4-dinitrophenylhydrazine) of Reissert compounds to aldehydes and the corresponding heterocyclic carboxylic acid derivatives. This reaction is fairly general for compounds of quinoline (178) and isoquinoline (179) (Table 18), but it is not applicable to pyridines as they rarely form Reissert compounds. The 3-hydroxyquino-line Reissert compound does not yield benzaldehyde, probably because acylation of the 3-hydroxy group prevents formation of the required cyclic intermediate (180). Some nitroquinolines and isoquinolines give low yields of benzaldehyde. Rather curiously, disub-stituted quinoline Reissert compounds yield less of the aldehyde than of the corresponding... 

The (lS)-5-amino-8,9-dihydroxy-2,3-dihydro-l//-pyrimido[l,2-a]quinoline-3-carboxylic acid (8) form of pyoverdin PaA was halogenated at position 7 with a 30-fold excess of ferric chloride and bromide in acidic water at room termperature for 18 h (97TL97). Acidic hydrolysis of (15)-5-amino-8,9-dihy droxy-2,3-hy dro-1 //-pyrimido [1,2-a] quinoline- 1-carboxylic acid (8) in boiling 6 N hydrochloric acid for 48 h gave the 5,8,9-trihydroxy derivative (90MI2). Treatment of 2,3-dihydro-l//-pyrimido[l,2-a]quinoline hydrochlorides with aqueous 10% sodium hydroxide gave 4a-hydroxy-2,3,4,4a-tetrahydro-l//-pyrimido[l,2-a]quinolines (60) (69YZ759). 

Ethyl 6-hydroxy-l-oxo-l//-pyrimido[l,2-a]quinoline-2-carboxylate was prepared from the 2-carboxylic acid in boiling ethanol in the presence of 3% hydrogen chloride for 4 h (77GEP2628751,77USP4031217). Heating ethyl 6-methoxy-l-oxo-l//-pyrimido[l,2-a]quinoline-2-carboxylate in ethylene glycol in the presence of triethylamine for 6 h yielded the 2-hydroxyethyl ester (75GEP2513930). 

Chemical Name (l,4 -Bipiperidine)-l -carboxylic acid, (4S)-3,4,12,14-tetrahydro-4,ll-diethyl-4-hydroxy-3,4-dioxo-lH-pyrano(3, 4 6,7) indolizino[l,2-b]quinolin-9-yl ester, monohydrochloride... 

EtOH), were first isolated in 1872 and 1877, respectively (14). Quin-amine was observed to give indole color reactions (7, 15), and 2,3-dimethylindole was a result of zinc dust distillation of the alkaloid (15). With chromic acid (9), the quinuclidine carboxylic acid (III) was obtained, and with nitric acid 3,6,8-trinitro-4-hydroxyquinoline was isolated (15, 16). This quinoline is a consequence of fission of the indole and recyclization, with nitration preceding and following these steps [cf. ozonolysis of yohimbine to furnish a 2,3-disubstituted 4-hydroxy-quinoline (17)]. 

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