2- thiazolidine-4-carboxylic

Phenylisocyanate added to a soln. of 620 mg. ethyl sjptro-cholestane-S -thiazoIidine-l -carboxylate, and allowed to stand overnight > 593 mg. N-phenylhydantoin of spiro-cholestane-3,2 -thiazolidine-4 -carboxylic acid. (S. Lieberman, P. Brazeau, and L. B. Hariton, Am. Soc. 70, 3094 (1948).)... 

Cysteine is first dissolved in distilled water which has been freed of oxygen by boiling. Formaldehyde of 30% (w/v) concentration is added while stirring and the temperature of the mixture rises, while the thiazolidine carboxylic acid begins crystallizing. The stirring is continued for 2 hours after which ethyl alcohol of 95% (w/v) concentration Is added to induce further crystallization. The mixture is left to stand for 24 hours at 4°C. The mixture is then filtered with retention of a crude product, which is purified by recrystallization from boiling distilled water. The crystals are then dried at about 40°C. The free acid is then converted to the sodium salt with NaOH. 

Kovacs-Hadady and Kiss [27] studied the chromatographic characteristics of thia-zolidinecarboxylic acid derivatives, formed by reaction of (i>) and (L)-penicillamine with various substituted benzaldehydes and heterocyclic aldehydes in order to evaluate the aldehydes as derivatizing agents for separation of the penicillamine enantiomers. The TLC method of Martens et al. [28] was used. Transformation to thiazolidine carboxylic acids with benzaldehyde and substituted benzaldehydes was not complete, so formaldehyde is still the preferred reagent for separation of the enantiomers. 

Isochem has set up a multipurpose electrochemical unit devoted to organic electrosynthesis. The unit located in Pithiviers (France) [115] is dimensioned for the production of 80 tons a year of cystein derivatives, such as cysteine base salts, carbocysteine, acetylcysteine, and thiazolidin carboxylic acids. 

Dimethyl-3,5-dimethyl-l//,3//-pyrrolo[l,2-r ][l,3]thiazole-6,7-dicarboxylate 399 (R = H) was prepared from cysteine 396 using the method developed of Padwa et al. <1989JOC644>. The thiazolidine carboxylic acid 397 (R = H), obtained by reaction of the cysteine with formaldehyde, was heated in the presence of acetic anhydride and DMAD to give the sulfide 399 by dipolar cycloaddition of the acetylene to the intermediate dipole 398 (Scheme 59) <2002J(P1)1795>. 

Aminothiazoline-4-carboxylic acid 2-lmino-4-thiazolidine-carboxylic acid... 

Similarly, 3-phenyl propionaldehyde gave rise to a 1 1.5 endo/exo mixture of adducts 110 (R = CH2CH2Ph), derived solely from reaction of the awfi-dipole. In an analogous fashion, thiazolidine carboxylic acid (111) also underwent awfi-dipole specific cycloaddition, with A-phenyl maleimide, after initial condensation with... 

L., Zhong, W., Xiao, J., Hu, Y., Li, S. (2006) FK506-binding protein ligands structure-based design, synthesis, and neurotrophic/neuroprotective properties of substituted 5,5-dimethyl-2-(4-thiazolidine)carboxylates. / Med Chem 49, 4059 071. 

Interestingly, however, another comparative study [24] revealed the capacity of other amines related to L-proline (S)-27 to function as organocatalysts in the Mannich reaction under modified reaction conditions [24]. As shown for a model reaction using preformed imines derived from o-anisidine, the thiazolidine carboxylic... 

Rommelsbacher, in following the concept of Holtz that mammalian alkaloids are formed from chemically reactive biogenic amines and amino acids by reaction with endogenously formed ketonic substrates under physiological conditions, has extended this idea to include indole-3-acetaldehyde. It was found that tryptamine, on incubation with pig brain and bovine brain, but not with liver tissue, formed the thiazolidine carboxylic acid 60 shown in Fig. 20 Ml). 

Finally, the enolates (8), (9), and (10) of oxazolidine and thiazolidine carboxylates have been used for the synthesis of enantiopure... 

Resolution of Amino Acids. For the optical resolution of racemic threonine via replacing resolution, (S)-proline was utilized as an optically active cosolute although the structure of the imino acid is different from that of threonine. The same procedure was applied less sucessfully to the resolution of (R,S)-thiazolidine carboxylic acid. ... 

Maier (1973) studied the physical sorption of volatile aroma constituents by foods using IR spectroscopy. He observed that aliphatic aldehydes such as propanal (C.3), hexanal (C.6), acrolein (C.16) were also reacting chemically with some amino compounds, specially with cysteine (formation of thiazolidine carboxylic acids), with other amino acids, with glutathione and with urea. The bound aldehydes are nevertheless, in most cases, released by heating with water, especially during the percolation of the coffee beverage. 

K., Shih, J. C., Seif, L, and Sweedler, J. V., Serotonin catabolism and the formation and fate of 5-hydroxyindole thiazolidine carboxylic acid, J. Biol. Chem., 281, 13463, 2006. 

Cysteine with pyridoxal can also give a thiazolidine carboxylic acid (XXXXVI), (Heyl et al., 1948) ... 

Many antigenic determinants may derive from penicillins but most is known about the benzylpenicilloyl (BPO) determinant, a bifunctional structure comprising a nonpolar phenylacetamide and a polar thiazolidine carboxylic acid end (Levine 1963) (Fig. 4). 

Lysine, mono-4-thiazolidinecarboxylate. See Lysine thiazolidine carboxylate Lysine 5-oxo-prolinate. See Lysine PCA Lysine PCA... 

Definition Lysine salt of thiazolidine carboxylic acid Empirical C10H20N3O4S Formula C6H14N2O2 C4H6NO2S Uses Surfactant in cosmetics... 

Lauryi hydroxysultaine Lauryi isoquinolinium bromide Laurylpyridinium chloride Lauryi pyrrolidone Lauryi sultaine Lecithin Linseed acid Lysine thiazolidine carboxylate Magnesium cocoate Magnesium coco-sulfate... 

In the case of cysteine (5) the product obtained is contaminated by cystine and also by thiazolidine carboxylic acid (obtained by reaction of cysteine and formaldehyde, the latter arising from hydrolytic decomposition of acetamidomethanol, see section VI). However, the product could easily be purified by using ion exchange columns. On the other hand, anhydrous conditions should avoid the decomposition of the acetamidomethanol and indeed a reaction using hydrogen fluoride as a solvent results in quantitative yield of the pure product". 

Heterocyclic compounds. Thiazolidine-4-carboxylic acid and 5,6-dimethylthiazolidine-4-car-boxylic acid are formed by formaldehyde condensation from cysteine and penicillamine, respectively. The derivatization of penicillamine has been published (195). Table 14 and Fig. 15 present a summary of these results. The chromatographic characteristics of the thiazolidine carboxylic acids formed by the reaction of D,L-peniciIlamine with various substituted benzaldehydes and heterocyclic aldehydes have also been studied (177). 3-Carboxy-morpholine was separated by Gunther et al. (102). 

NPRO=N-nitrosoproline, NHPRO = N-nitroso-4-hydroxyproline, NHMTCA carboxylic acid, NTCA = N-nitroso-4-thiazolidine carboxylic acid, NMTCA = = N-nitroso-2-(hydroxymethyl)-4-thiazolidine N-nitroso-2-methyl-4-thiazolidine carboxylic acid. ... 

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