Kidwai, Akhlaq R. et al. published their research in Compt. Rend. in 1963 | CAS: 6639-06-1

3-(1H-Indol-1-yl)propanoic acid (cas: 6639-06-1) belongs to indole derivatives. Indole exists overwhelmingly in the 1H-indole form as do other simple indoles. Indole plays a fundamental role for QS in E. coli, being one of the signal molecules responsible for the transcription of a variety of genes (gabT, and tnaB ASTD). Safety of 3-(1H-Indol-1-yl)propanoic acid

Use of formic acid as a cyclization agent in the synthesis of indoles by the Fischer method was written by Kidwai, Akhlaq R.;Khan, Naseem H.. And the article was included in Compt. Rend. in 1963.Safety of 3-(1H-Indol-1-yl)propanoic acid This article mentions the following:

Indoles have been prepared by cyclization of simple or substituted phenylhydrazones of aldehydes, ketones, or ketonic acids by ZnCl2, BF3, H2SO4, AcOH, polyphosphoric acid, aqueous AcOH or HCl, or EtOH-HCl. HCO2H (I) was also found to be a suitable cyclization agent. II (R = Ph, R’ = H, P” = CO2H) (1 g.) in 40 ml. 50% I refluxed 4 hrs., evaporated in vacuo on a H2O bath, the residue dissolved in H2O, the solution extracted with Et2O, the extract washed with aqueous NaHCO3, the combined alk. solutions treated with C, and acidified gave 91% III (R = Ph, R’ = H, R” = CO2H), m. 186° (EtOH). Similarly were prepared, from II (R = Ph, R’ = NO2, R” = CO2H), 70% III (R = Ph, R’ = NO2, R” = CO2H) (IV), m. 247.5° (EtOH-H2O), and from II [R = CH2C(NHAc)(CO2Et)2, R’ = R” = H], 63% III [R = CH2C(NHAc)(CO2Et)2, R’ = R” = H], m. 158° (C6H6-petr. ether). Whether the NO2 group in IV was in the 4- or 6-position was undetermined In the case of IV, the product was isolated directly from the Et2O solution Neg. results were obtained with the phenylhydrazones of AcCO2H and AcH, which could not be cyclized with the other above-cited cyclization agents. In the experiment, the researchers used many compounds, for example, 3-(1H-Indol-1-yl)propanoic acid (cas: 6639-06-1Safety of 3-(1H-Indol-1-yl)propanoic acid).

3-(1H-Indol-1-yl)propanoic acid (cas: 6639-06-1) belongs to indole derivatives. Indole exists overwhelmingly in the 1H-indole form as do other simple indoles. Indole plays a fundamental role for QS in E. coli, being one of the signal molecules responsible for the transcription of a variety of genes (gabT, and tnaB ASTD). Safety of 3-(1H-Indol-1-yl)propanoic acid

Referemce:
Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles