Wahl, Oliver et al. published their research in Journal of Pharmaceutical and Biomedical Analysis in 2018 | CAS: 444-27-9

Thiazolidine-4-carboxylic acid (cas: 444-27-9) belongs to thiazolidine derivatives. Derivatives, thiazolidines, are known. For example, the drug pioglitazone contains a thiazolidine ring. Another drug that contains a thiazolidine ring is the antibiotic penicillin. Thiazolidines have been applied as prodrug derivatives for various steroids containing a 3-carbonyl group to improve their topical anti-inflammatory activity. Reference of 444-27-9

Impurity profiling of N,N’-ethylenebis-L-cysteine diethyl ester (Bicisate) was written by Wahl, Oliver;Cleynhens, Jan;Verbruggen, Alfons M.;Holzgrabe, Ulrike. And the article was included in Journal of Pharmaceutical and Biomedical Analysis in 2018.Reference of 444-27-9 This article mentions the following:

A HPLC-UV-CAD method with a HILIC column for impurity profiling of the 99Tc chelating agent bicisate has been developed and evaluated. Bicisate and its impurities were separated by means of isocratic elution on a zwitterionic stationary phase using a mixture of 7.5 mmol/L trifluoroacetic acid and acetonitrile (47.5:52.5 V/V) as the mobile phase. Five different bicisate batches of a manufacturer were tested using the method. In addition LC-MS experiments were conducted in order to identify the impurities. The predominant impurities found were the oxidation product (disulfide), the monoester of ethylene dicysteine and an unknown compound with an m/z of 293 in ESI pos. mode. A new degradation product of bicisate, bicisate lactam, was identified during sample solution stability assessment. In the experiment, the researchers used many compounds, for example, Thiazolidine-4-carboxylic acid (cas: 444-27-9Reference of 444-27-9).

Thiazolidine-4-carboxylic acid (cas: 444-27-9) belongs to thiazolidine derivatives. Derivatives, thiazolidines, are known. For example, the drug pioglitazone contains a thiazolidine ring. Another drug that contains a thiazolidine ring is the antibiotic penicillin. Thiazolidines have been applied as prodrug derivatives for various steroids containing a 3-carbonyl group to improve their topical anti-inflammatory activity. Reference of 444-27-9

Referemce:
Thiazolidine – Wikipedia,
Thiazolidine – ScienceDirect.com