Indole acidity

The formation of l-methyl-5-aminonaphthalene when dihydro-lysergic acid is fused with potassium hydroxide requires rings (A) and (Cb The presence of an indole nueleus (rings (A) and (B) ) is established by the formation of 3 4-dimethylindole, m.p. 115-7°, pierate, m.p. 185-7°, by decarboxylation of an indole acid obtained when dihydrolysergic acid is fused with potassium hydroxide. ... 

A number of heteroaryl-fused 3-oxo-l,4-thiazepine-5-carboxamides, for example the indole-fused derivatives 133, have been accessed using a modification of the four-component Ugi condensation. In the case of 133, the starting point was the indolic acid 132. The yields of 133 were moderate to good (for example, R = -Pr, R2= EtO-(CH2)3, 66%) <06JOC2811>. 

The diketoindoles 777 were prepared in three steps starting from indol-3-ylacetic acid (680) and 5-chloro indol-3-ylacetic acid (774) in 75% and 66% overall yield, respectively. The indole acids 680 and 774 were converted into Weinreb amides 775, followed by reaction with ethyl Grignard reagent to afford the corresponding indol-3-yl ketones 776. In order to introduce the second carbonyl moiety, the 3-substituted... 

Physicochemical properties of azines, 5, 69 of pyrroles. II, 383 3-Piperideines, 12, 43 Polyfluoroheleroaromatic compounds, 28, I Polymerization of pyrroles and indoles, acid-catalyzed, 2, 1... 

Metabolic studies by Milne et al. (M8) showed that in Hartnup disease the renal aminoaciduria is more constant than the excessive excretion of indican and indolic acids (indoleacetic acid, indolelactic acid, and indoleacetylglutamine). After ingestion of L-tryptophan in this disease there is usually delayed and incomplete absorption from the gut of the amino acid which is partly converted, by intestinal bacteria, to indole... 

The results obtained (M8) suggest that a defective transport of tryptophan is established across the cells of the jejunum and across the proximal renal tubules. The reduced conversion of tryptophan to kynurenine is probably due to a deficiency of tryptophan pyrrolase or to a lower transport of substrate to the enzyme. According to the same authors (M8), the cerebellar ataxia may be ascribable to intoxication by retained indolic acids. 

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