Pangajavalli, S. et al. published their research in Acta Crystallographica, Section E: Crystallographic Communications in 2019 | CAS: 444-27-9

Thiazolidine-4-carboxylic acid (cas: 444-27-9) belongs to thiazolidine derivatives. The thiazolidine ring is a cyclic N,S acetal, and most syntheses of perhydrothiazolo [3,2-a]pyridines construct the five-membered ring by condensation of aldehydes or ketones either as such or masked. In addition, the use of thiazolidines as an inhibitor of tyrosyl-DNA phosphodiesterase Iand influenza neuraminidase, pro-drugs for the treatment of cystinosis, radioprotective against γ-irradiation and as S1P1 receptor agonist has also been reported.Name: Thiazolidine-4-carboxylic acid

Crystal structures of 6a,6b,7,11a-tetrahydro-6H,9H-spiro[chromeno[3′,4′:3,4]pyrrolo[1,2-c]thiazole-11,3′-indoline]-2′,6-dione and 5′-methyl-6a,6b,7,11a-tetrahydro-6H,9H-spiro[chromeno[3′,4′:3,4]pyrrolo[1,2-c]thiazole-11,3′-indoline]-2′,6-dione was written by Pangajavalli, S.;Ranjithkumar, R.;Srinivasan, N.;Ramaswamy, S.;Selvanayagam, S.. And the article was included in Acta Crystallographica, Section E: Crystallographic Communications in 2019.Name: Thiazolidine-4-carboxylic acid This article mentions the following:

The title compounds, C20H16N2O3S, (I), and C21H18N2O3S, (II), differ by the presence of a Me group in position 5 on the 1H-indole-2-one ring of compound (II). The two compounds have a structural overlap r.m.s. deviation of 0.48 Å. There is a significant difference in the conformation of the thiazolidine ring: it has a twisted conformation on the fused N-C bond in (I), but an envelope conformation in compound (II) with the S atom as the flap. The planar pyrrolidine ring of the indole ring system is normal to the mean plane of the five-membered pyrrolidine ring of the pyrrolothiazole unit in both compounds, with dihedral angles of 88.71 (9) and 84.59 (8)°. The pyran rings in both structures have envelope conformations with the methylene C atom adjacent to the C=O group as the flap. In both compounds, there is a short intramol. C-H…O contact present. In the crystal of (I), mols. are linked by C-H…O hydrogen bonds forming chains propagating along the b-axis direction. The chains are linked by N-H…π interactions, forming layers parallel to (10 [inline formula omitted]). In the crystal of (II), mols. are linked by pairs of N-H…O hydrogen bonds, forming inversion dimers which are linked by C-H…O hydrogen bonds to form a three-dimensional structure. In the experiment, the researchers used many compounds, for example, Thiazolidine-4-carboxylic acid (cas: 444-27-9Name: Thiazolidine-4-carboxylic acid).

Thiazolidine-4-carboxylic acid (cas: 444-27-9) belongs to thiazolidine derivatives. The thiazolidine ring is a cyclic N,S acetal, and most syntheses of perhydrothiazolo [3,2-a]pyridines construct the five-membered ring by condensation of aldehydes or ketones either as such or masked. In addition, the use of thiazolidines as an inhibitor of tyrosyl-DNA phosphodiesterase Iand influenza neuraminidase, pro-drugs for the treatment of cystinosis, radioprotective against γ-irradiation and as S1P1 receptor agonist has also been reported.Name: Thiazolidine-4-carboxylic acid

Referemce:
Thiazolidine – Wikipedia,
Thiazolidine – ScienceDirect.com