5-Methoxyindole-2-carboxylic acid

The position of the sugar residue in the dihydroindole portion can be determined by methylation of the pigment with diazomethane and subsequent alkaline degradation of the resulting neobetanin derivative. In the case of 5-0-glycosides, 5-hydroxy-6-methoxyindole-2-carboxylic acid is obtained, whereas the 6-O-glyco-sides yield 6-hydroxy-5-methoxyindole-2-carboxylic acid (47,48). The indole carboxylic acids are easily identified by TIjC. 

C10H9NO3 5-methoxyindole-2-carboxylic acid 4382-54-1 27.50 1.2860 2 19122 Cl OH1002 p-methylcinnamic acid 1866-39-3 27.69 1.0799 2... 

Hanson, R.L., Ray, P.D., Walter, P., Lardy, H.A. Mode of action of hypoglycemic agents. I. Inhibition of gluconeogenesis by quinaldic acid and 5-methoxyindole-2-carboxylic acid. J. biol. Chem. 244, 4351-4359 (1969)... 

DMSO, NaCN, 125-180°, 5-48 h, 65-90% yield.This cleavage reaction is successful for aromatic systems containing ketones, amides, and carboxylic acids mixtures are obtained from nitro-substituted aromatic compounds there is no reaction with 5-methoxyindole (180°, 48 h). 

Hydrolysis of 1-acetoxy- or l-hydroxy-3-cyanoindole (115) by hydrogen peroxide or 1 M sodium hydroxide gave the corresponding amide, while QM sodium hydroxide gave the 3-carboxylic acid which decomposed rapidly at room temperature with diazomethane, the last compound gave the stable methyl l-methoxyindole-3-carboxylate [78JCS(P1)1117]. 1-... 

In the assay described by Smit et al. (1990), 5,6-dihydroxyindole-2-carboxylic acid was the substrate. Two products are formed, 5-hydroxy-6-methoxyindole-2-carboxylic add and 6-hydroxy-5-methoxyindole-2-carbox-ylic add. 

Additional halogenation of 78 and 81 exhibits interesting results [28]. Bromination (1.3-mol eq.) of the former in AcOH provides methyl 6-bromo-5-iodoindole-3-carboxylate (82, 56%) and the corresponding carboxylic add (83, 18%). On the other hand, bromination of the latter gives complex mixtures of products under various reaction conditions. Relatively clean reaction takes place with Br2 (1.3-mol eq.) in AcOH at 100 °C providing methyl 6-bromo- (84, 17%), methyl 2-bromo-5-iodo-l-methoxyindole-3-carboxylates (85, 33%), 5-iodo-l-methoxyindole-3-carboxylic acid (86, 7%),... 

Tegaserod is metabolized mainly via two pathways. The first is a presystemic acid-catalyzed hydrolysis in the stomach followed by oxidation and conjugation, which produces the main metabolite of tegaserod, 5-methoxyindole-3-carboxylic... 

A mixture of 9.5 g pyrrolyl-2-aldehyde, 29.2 g dimethyl-succinate and NaH (9.6 g of 50% suspension in oil) in 100 ml benzene is stirred at room temperature 6 hours, cooled and carefully acidified with glacial acetic acid. Add water and ether and dry, evaporate in vacuum or work up (JACS 72,501 (1950), JCS 1025(1959)) to get ca. 17 g (80%) 3-methoxycarbonyl-4-(2 -pyrrolyl)-3-butenoic acid (I) (recrystallize-acetone-benzene). A mixture of 12 g (I), 7 g sodium acetate and 70 ml acetic anhydride is left overnight at room temperature with occasional shaking. Then gradually raise the temperature to 70-75° over 2 hours, maintain for 4 hours and work up (see JCS 1714(1955), 986( 1958)) to get ca. 8 g (60%) methyl-4-acetoxy-indole-6-carboxylate (II) (recrystallize-petroleum ether). If desired, this can be converted to 4-OH-indole-6-COOH and 4-methoxyindole-COOH as described in the ref. or decarboxylated as described elsewhere here. If the 1-methyl cpd. is used, 1-Me-indole results. 

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