Synthesis and spectral properties of new water-soluble fluorescent label squarylium indocyanine dyes was written by Song, Bo;Zhang, Qian;Peng, Xiao-Jun;Ma, Wen-Hui;Wang, Bing-Shuai;Fu, Xin-Mei. And the article was included in Gaodeng Xuexiao Huaxue Xuebao in 2008.Reference of 146368-07-2 This article mentions the following:
Six water-soluble squarylium indocyanine dyes were synthesized and their structures were confirmed by 1H NMR and MS spectroscopy. The absorption and emission spectra of these dyes in water, methanol, ethanol, DMF, DMSO were studied. The spectra of these dyes exhibit a neg. solvatochromism. The photo stability of these dyes in water was investigated as well. It is demonstrated that the electron-withdrawing group on N-position of cyanine dyes improves the photo stability as compared with the dyes with electron-donating group which decreases the photo stability obviously. In the experiment, the researchers used many compounds, for example, 1-Ethyl-2,3,3-trimethyl-3H-indol-1-ium-5-sulfonate (cas: 146368-07-2Reference of 146368-07-2).
1-Ethyl-2,3,3-trimethyl-3H-indol-1-ium-5-sulfonate (cas: 146368-07-2) belongs to indole derivatives. Indole, also called Benzopyrrole, a heterocyclic organic compound occurring in some flower oils, such as jasmine and orange blossom, in coal tar, and in fecal matter. More than 200 indole derivatives have already been marketed as drugs or are under advanced stages of clinical trials.Reference of 146368-07-2
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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