Thiopropionic acid

Esters of thiopropionic acid tend to decompose at high processing temperatures, and their odor makes them unsuitable for some food-packaging apphcations. 

Among the sulphur-containing substances, esters of 3,3 -thiopropionic acids S(CH2CH2COOR)2, where R=C 4—C20 [18], are most efficient. 

In another approaeh [88IJC(B)570], reaetion of 2-mereapto-4,5-di-p-tol-ylimidazole 43 with a-halo carboxylie acids enabled the synthesis of several imidazo[2,l-h]thiazoles. Acylative ring closure of 4,5-di-p-tolylimidazo-2-thioacetic acid (44, R = H) or 2-thiopropionic acid (44, R = Me) provides 5,6-di-p-tolylimidazo[2,l-h]thiazole-3(2//)-one (45, R = H) or its 2-methyl analog (45, R = Me). The synthesis of annelated imidazo[2,l-h]thiazoles (e.g., 46) can be achieved in one step by reaction of 2,3-dichloroquinoxaline with 43. The intramolecular eyelization of l-vinylimidazole-2-thiones to 2,5-dimethyl-3,6-arylimidazo[2,l-h]thiazoles with excellent yield has been reported (93T6619). 

S-PENTACHLOROPHENYL-2- S-PENTACHLOROPHENYL-2-THIOACETIC ACID HYDROXY-3-THIOPROPIONIC ACID... 

By the action of nitrous acid in hydrochloric acid solution on bromo-phenylcystine, prepared by Baumann s method, chlorobromophenyl-thiopropionic acid was obtained, which, on reduction, gave bromophenyl-thiolactic acid. This was identical with the substance prepared from j8-iodopropionic acid and sodium bromophenylmercaptan —... 

Fig. 2. Two-fold sequential nucleophilic substitution at support-bound 2,3-dichloropro-pionic acid for the synthesis of 3-amino-2-thiopropionic acid derivatives. X = O, NR.

The elimination/addition reaction already proceeded at room temperature when the dichloropropionic acid had been linked as an ester to the support, but required heating when an amide linkage had been chosen. When amines with low nucleophilicity were used, such as aniline or a-amino acid esters, higher reaction temperatures were also beneficial. Occasional by-products for this reaction sequence were acrylic acid derivatives or the corresponding hydrogenated products (2-thiopropionic acid derivatives). These by-products were usually formed when a very small excess of amine was used in the elimination/addition step. Both the thiols and the amines used in this reaction sequence could be polyfunctional, as illustrated by the examples sketched in Fig. 3. 

Pogocki D, Schoneich C (2002) Computational characterization of sulfur-oxygen-bonded sulfuranyl radicals derived from alkyl- and (carboxyalkyl)thiopropionic acids evidence for a -type radicals. J Org Chem 67 1526-1535... 

Bergman, J.A., et al (2011). S-farnesyl-thiopropionic acid (FTP) triazoles as novel, potent inhibitors of isoprenylcysteine carboxyl methyltransferase (Icmt) manuscript submitted. ACS Med Chem Lett, (unpublished data). 

All these enzymes have similar specificity and require the L-cysteine sulfoxide portion of the molecule. S-alkyl cysteines are not substrates 18, 24, 27, 39) neither are sulfoxides of N-substituted L-cysteine, / -di-methyl-L-cysteine, y8-thiopropionic acid 18), D-cysteine 19), and dl-methionine 18, 24, 39), nor do the enzymes act on L-cysteine itself 24, 27, 39), cysteic acid, cysteinesulfinic acid 24, 27), or cycloalliin 24, 39). There may be some action on S-ethylcysteine sulfone (42). 

Mercapto-propanoic acid 3-Mercaptopropionic acid NSC 437 Propanoic acid, 3-mercapto- Propionic acid, 3-merc-apto- 3-Thiopropanoic acid 3-Thiopropionic acid P-Thiopropionic acid. 

Camatero J, Adeva A, Muir T (2000) 3-Thiopropionic acid as a highly versatile multidetachable thioesler resin linker. Lett Pept Sci 7 17-21... 

CAS 52-90-4 EINECS/ELINCS 200-158-2 FEMA 3263 INS920 E920 Synonyms L-2-Amino-3-mercaptopropanoic acid (+)-2-Amino-3-mercaptopropionic acid a-Amino-P-thiopropionic acid L-2-Amino-3-thiopropionic acid Cystein Cysteine (INCI) 3,3 -Dithiobis (2-aminopropanoic acid) P-Mercaptoalanine L-P-Mercaptoalanine Tioserine Classification A nonessential amino acid Empirical C3H7NO2S Formula HSCH2CH(NH2)COOH Properties Colorless cryst. sol. in water, ammonium hydroxide, acetic acid insol. in ether, acetone, benzene, carbon disulfide, CCU m.w. 121.16 m.p. 220 C (dec.)... 

Thiopropanoic acid 3-Thiopropionic acid P-Thiopropionic acid. See 3-Mercaptopropionic acid... 

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