Pyridine-3-carboxylic acid ethyl ester

Chemical Name 2-amino-6-benzyl-4,5,6,7-tetrahydrothieno[2,3-c] pyridine-3-carboxylic acid ethyl ester... 

CN 2-amino-4,5,6,7-(etrahydro-6-(phenylmethyl)thieno[2,3-f]pyridine-3-carboxylic acid ethyl ester monohydrochloride... 

Ethyl-l,2,3,6-tetrahydro-pyridine-3-carboxylic acid ethyl ester and (+)-tartaric acid were dissolved in hot 95% ethanol. The resulting solution was allowed to slowly cool to room temperature and refrigerated overnight. The crystals were filtered, washed with cold ethanol, and recrystallized from 95% ethanol, cooling as before to give the (+)-tartrate salt of (+)-5-ethyl-l,2,3,6-tetrahydro-pyridine-3-carboxylic acid ethyl ester. 

Pyridine-3-carboxylic acid ethyl ester (ethyl nicotinate)... 

To a stirred suspension of 4.6 g (13.8 mmoles) of the (S)-3-(2-hydroxyethyl)-5-(2-oxo-l,3-oxazolidin-4- ylmethyl)-lH-indol-2-carboxylic acid ethyl ester in 42 ml of dichloromethane were added 4.2 ml of pyridine, 3.9 g (20.7 mmoles) oftosyl chloride and 170 mg (1.38 mmoles) of dimethylaminopyridine and the stirring continued at room temperature for 20 hours. The reaction mixture was poured over 20 ml of 3 N, HCI precooled to 0°C and extracted twice with dichlormethane. The organic phases were washed with brine, dried on anhydrous sodium sulphate and the solvent evaporated to dryness. The evaporated solid was crystallised with isopropyl alcohol to give 6.4 g (95%) of the title compound as a white crystalline solid. Melting point 166.4°-168.2°C. 

Pyridine (2 carboxylic acid ethyl ester 3 methyl, 6 ethyl) imazethapyr... 

Preparation of 5-methyl-4-(lH-pyrrolo[2,3-b]pyridin-5-yloxy)-pyrrolo [2,l-f][l,2,4]triazine-6-carboxylic acid ethyl ester... 

Ttnoridine. 2-Amino-4tS,6, -tetrahydro-6-(phen-ylmethyl)thieno[2,3-c]pyridine-3-carboxyiic acid ethyl ester 2-amino-6-benzyl-4,S,6,7-tetrahydrothieno(2,3-cJpyridine-3-carboxylic acid ethyl ester 2-amino-3-ethoxycarbonyl-6-benzyl-4,5,6,7-tetrahydrothieno[2,3-c]pyridine ethyl 2-amtno -6 -benzyl -4,5,6,7 -tetrahydrolhieno[2,3 -cjpy ridine-3 -carboxylate Y-3642. CJ,Ha,Nj02S mol wt 316.42. C 64.53%, H 6.37%, N 8.85%, 0 10.11%. S 10.13%. Ptepn Nakanishi et al. Ger. pat. 1,812,404 eidem. 113. pat. 3,-563,997 (1969, 1971 both to Yoshitoml). Pharmacological... 

To a stirred solution of 0.1 mmol (4R,VS)- and (45,l 5 )-4-(l -f rf-butoxycarbonyl-amino-2 -hydroxyethyl)-6-methyl-2-oxo-l,2,3,4-tetrahydropyrimidine-5-carboxylic acid ethyl ester in 1 mL anhydrous CH2CI2 were added 29 mg (R)-Qf-methoxy-a -(trifluoro-methyl)phenylacetic acid (0.12 mmol), 25 mg 1,3-dicyclohexylcarbodiimide (0.12 mmol), and a catalytic amount of 4-A, A-(dimethylamino)pyridine. The mixture was stirred for an additional 12 h at room temperature, then concentrated. The residue was taken into EtOAc, washed with saturated aqueous NaHCOs and brine, dried over Na2S04, and concentrated. The residue was purified by preparative TLC, affording the corresponding Mosher ester in almost quantitative yield. 

C8H9NO2 pyridine-2-carboxylic acid ethyl ester 2524-52-9 ... 

To a solution of the S-(+)-4-acethoxy-9-[2-(5-ethyl-l,2,3,6-tetrahydro-pyridin-3yl)-l-(lH-indol-2-yl)-l-methoxycarbonyl-ethyl]-3a-ethyl-5-hydroxy-8-methoxy-6-methyl-3a,4,5,5a,6,ll,12,12b-octahydro-lH-6,12a-diaza-indeno[7,l-ca]fluorene-5-carboxylic acid methyl ester in dioxane and glacial acetic acid was added 37% aqueous formaldehyde and the mixture stirred at 35°C for 24 h. The solution was evaporated in vacuo and the residue suspended in chloroform and washed with cold aqueous 5% K2C03 solution. The chloroform layer was dried (MgS04), filtered, and evaporated. The residue was chromatographed eluting with EtOAc/MeOH, 10% NH4OH to give the product navelbine. 

The same method was also used for the synthesis of the anti-malarial compound mefloquine. Heterocyclization of 2-trifluoromethylaniline with trifluoroacetic acid ethyl ester provides 2,8-6w-(trifluoromethyl)-4-hydroxyquinoline. Bromination with phosphorous tribromide, followed a carbon monoxide introduction, affords 2,7-trifluoromethyl-4-carboxylic acid quinoline. Amide formation and pyridine reduction completes the synthesis providing mefloquine in high yields. ... 

Esters of pyridine-carboxylic acids react normally with compounds containing activated methylene groups. The reactions are valuable, for example as routes to acylpyridines. The ethoxide-catalysed condensation of ethyl pyridine carboxylates with ethyl acetate has often been described early work suggested that esters of nicotinic acid gave lower yields than their isomers, but this is not so . Many esters other than ethyl acetate have been used and a number of substituted pyridine esters > Condensations with picolines to give desoxypyridoins are of practical value (p. 380). 

By oxidation with chromic acid, this is converted into cyclohexanone-3-carboxylic acid, in which the —CH. OH— group is converted into the —CO— group. This is converted into its ethyl ester and treated with magnesium methyl iodide, and the product, on hydrolysis, yields l-methyl-cyclohexane-l-ol-3-carboxylic acid, which is converted byhydro-bromic acid into 1-bromo-l - methyl - cyclohexane - 3 - carboxylic acid. When this is digested with pyridine, hydrobromic acid is eliminated and yields l-methyl-A -cyclohexane-3-carboxylic acid of the formula—... 

There is obtained from 4-[)3-[5-methyl-isoxazolyl-(3)-carboxamido]-ethyl]-benzene-sulfonamide (prepared from 5-methyl-isoxazole-(3)-carboxylic acid chloride and 4-()3-aminoethyl)-benzene-sulfonamide hydrochloride, MP 213° to 214°C in pyridine) and chloroformic acid methyl ester, in a yield of 69%, the compound N-[ [-4-[)3-[5-methyl-isoxazolyl-(3)-carbox-amido] -ethyl] ] -benzene-sulfonyl] ] -methyl-urethane in the form of colorless crystals of MP 173°C. 

The organic layer wasdried with anhydrous magnesium sulfate and then filtered. The solution was concentrated under vacuum at 30°C to 35°C until reduced to half of its original volume and then cooled to 5°C to allow the crystallization of the compound. Thus, the cake was filtered, washed with cool ethyl acetate, and dried under vacuum. Yield 74% (76.7 g) of phthalidyl ester of 2-(3 -trifluoromethylanilino)-pyridin-3-carboxylic acid, melting point 165°C to 167°C. 

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