Thiomalic acid

Many natural and synthetic organic compounds are hydroxy dicarboxyhc acids (see also Hydroxycarboxylic acids). This article discusses mainly malic and tartaric acids thiomalic acid is included because of its stmctural similarity to malic acid. 

Thiomahc acid [70-49-5] (mercaptosuccinic acid), C H O S, mol wt = 150.2, is a sulfur analogue of malic acid. The properties of the crystalline, soHd thiomalic acids ate given in Table 6. The racemic acid has the following acid dissociation constants at 25°C pTf i — 3.30 pffc2 — 4.94. 

Thiolactic acid, m22 Thiomalic acid, m25 Thiosalicylic acid, ml8 Thiosinamine, a97 2-Thioxo-4-thiazolidinone, r7 Threonine, al85 Tiglic acid, ml69... 

Soil. In soil, malathion was degraded by Arthrobacter sp. to malathion monoacid, masphoro-dithioate. After 10 d, degradation yields in sterile and nonsterile soils were 8, 5, and 19% and 92, 94, and 81%, respectively (Walker and Stojanovic, 1974). Chen et al. (1969) reported that the microbial conversion of malathion to malathion monoacid was a result of demethylation of the 0-methyl group. Malathion was converted by unidentified microorganisms in soil to thiomalic acid, dimethyl thiophosphoric acid, and diethylthiomaleate (Konrad et al, 1969). 

Chemical/Physical. Hydrolyzes in water forming cis-diethyl fumarate, tra/ s-diethyl fumarate (Suffet et ah, 1967), thiomalic acid, and dimethyl thiophosphate (Mulla et al., 1981). The reported hydrolysis half-lives at pH 7.4 and temperatures of 20 and 37.5 °C were 10.5 and 1.3 d, respectively (Freed et al, 1977). In a preliminary study, Librando and Lane (1997) concluded that the hydrolysis of malathion is very sensitive to pH. At pH 8.5, <5% of the malathion remains after 2 d, whereas at pH 5.7, >90% remains after 20 d. 

Tetramethylhydrazine, see Dimethylamine Tetramethylsuccinonitrile, see Aldicarb Tetrazene, see Naphthalene 2-Thiazolidinethione-4-carboxylic acid, see Captan 1.1 -Thiobis-ethane, see Phorate 3.3 -Thiobis(methylene)-1.2.3-benzotriazin-4(3Afl-one, see Azinnhos-methyl Thiomalic acid, see Malathion Thiomethylbenzazimide, see Azinphos-methyl Thiophene, see Benzene Thiophenol, see Fonofos Thiophosphoric acid, see Phorate Thiram monosulfide, see Thiram o-Tolualdehyde, see oXylene m-Tolualdehyde, see m-Xylene p-Tolualdehyde, see p-Xylene Toluene, see Benzene. 2-ChlorobiDhenyl. 4 Chlorobinhenyl. Isobutylbenzene, Methylcyclohexane, Styrene, p-Xylene... 

Thiomalic acid [70-49-5] M 150.2, m 153-154°. Extracted from aqueous soln several times with ethyl ether, and the aqueous soln freeze-dried. 

V-Thiomalic acid can be prepared from bromosuccinic acid by reaction with KiS. The two enantiomers can be obtained from the corresponding optically active potassium hromosuccinales. 

Thiolpurine, AE02 6-Thiolpurine, AE03 Thiomalic acid, AC89 Thiopental sodium, AUOl Thiophene, AC6l... 

The kinetics of reaction of a number of A-nitrosothiols (334) in water with mercury(II) salts have been reported. Reaction is first order in both reactants and the products are nitrous acid and the corresponding thiol-Hg2+ complex. The mechanism involves slow attack by water at the nitrogen atom in the complex.300 The same group has also studied the copper(II)-catalysed decomposition of the, -nitrosothiols derived from penicillamine, cysteamine, thiomalic acid, A -acetylpenicillaminc, and cysteine.301... 

Thiolactic acid, m21 Thiomalic acid, m23 4,4 -Thioresorcinol, tl45 Thiosalicyclic acid, ml 6 Thiosinamine, alOl 2-Thixo-4-thiazolidinone, r3 Threonine, al 87 Tiglic acid, ml 61... 

This is exemplified by the polymerization of methyl methacrylate carried out in the presence of thiomalic acid 105) which is an efficient transfer agent. The reaction scheme can be written as ... 

Similarly, dicarboxylic transfer agents were used in telomerization. For instance, Yamashita [283-288] realized the synthesis of MMA macromonomer by using thiomalic acid as a transfer agent (Scheme 57). 

Dicarboxyl terminated PMMA was prepared using thiomalic acid as a chain transfer agent [155] (Scheme 43). 

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