Thio carbamates

The only practical method for preparing alkylene thioureas is by the action of the diamines upon carbon disulfide in aqueous alcohol. The final heating is essential to convert the thio-carbamic acid into the cyclic compound, the addition of hydrochloric acid being beneficial. ... 

Inherent in the reduction of asymmetrically substituted cyclic imides is the problem of regiose-lectivity. Imides, in which one carbonyl group is part of a (thio)carbamate or urea function, usually show complete chemoselectivity for reduction of the other carbonyl group, indicated with an arrow. 

Danielson LL, Gentner WA. 1970. Effect of solvent composition on inactivation of several phenyl and thio carbamate herbicides in soil. Proceedings of the Northeastern Weed Control Conference 24 308-312. 

Involving extraction with aqueous sodium carbonate solution (16). This loss of oxygen probably Involves an oxathliran intermediate 18 which can also extrude sulfur. Desulfuration to form the thio-carbamate (. . 12)is normally a minor pathway but becomes major... 

Other oxidation products of sulfallate are formed via thio-carbamate as discussed before. 

Figure 1. Oxidation and other reactions of dialiate and triallate indicating mutagenic activities of the products in the S. typhimurium TA 100 assay (revertants/ nanomole without activation/with activation / designates no data available). 2-Chloroacrolein is a dialiate metabolite in the mouse liver microsome-NADPH system. Dichloroallylsulfonic acid is a urinary metabolite of dialiate. The other compounds are potential metabolites of the respective thiocarbamates. The thio-carbamate sulfoxides are unstable at 25°C.

The dichloroacetal 53 N-acylated carbazole in the presence of stannic chloride producing 54, and trichloromethylthiomethane led to the thio-carbamate 55 on reaction catalyzed by zinc chloride. Carbazole reacts... 

NBD-C1 reacts with the liberated amines of dithio- and thio-carbamates to produce fluorescent derivatives. The products are separated by TLC [177]. The method is similar to that described earlier for methylcarbamate insecticides (see Section 4.2.4.2.2). The carbamates are hydrolyzed in base and the liberated amines are treated as described for methylcarbamates or by the technique described for biogenic amines (Section 4.2.1.2.2). 

Nagy, I., S. Verheijen, A. Deschrijver, J. Vandamme, P. Proost, G. Schoofs, J. Vanderleyden, and R. Demot (1995c). Characterization of the Rhodococcus spp. NI86/21 gene encoding alcohol -N,N -dimethyl-4-nitrosaniline oxidoreductase inducible by atrazine and thio-carbamate. Arch. Microbiol., 163 439 -46. 

Chemical Name 2,3,3-trichloro-2-propene-l-thiol diisopropylcarbamate S-(2,3,3-trichloro-allyl)diisopropyl-(thio-carbamate) A-(2,3,3-trichloro-2-propenyl) bis(l-methylethyl)-carbamothioate Uses herbicide to control wild oats in lentils, barley, peas, and winter wheat. 

The toxicity of methyl isocyanate comes as a surprise if its high sensitivity to hydrolysis is considered. But actually, it may reach its site of action in the human body largely undecomposed. This is due to the reversible addition of another nucleophile to this heterocumulene. The tripeptide gluthathione, which is supposed to protect the body against oxidizing agents, adds to the C=N double bond of the isocyanate by means of its thiol group whereby the thio-carbamate is formed. When the latter decomposes in a reversal to its formation reaction, it releases the intact toxic methyl isocyanate. 

E2 elimination reactions occur preferentially when the leaving groups are in an anti copla-nar arrangement in the transition state. However, there are a few thermal, unimolecular sy -eliminations that produce alkenes. For example, pyrolysis of several closely related amine oxides, sulfoxides, selenoxides, acetates, benzoates, carbonates, carbamates and thio-carbamates gives alkenes on heating (Scheme 4.10). The syn character of these eliminations is enforced by a five- or six-membered cyclic transition states by which they take place. 

DIHYDRO-2,2-DIMETHYL-7-BENZO-FURANYLMETHYL((4-NITROPHEN-YL)THIO)CARBAMATE... 

METHYL((METHYL((((5-METHYL-1,3-OXATHIOLAN-4-YLIDENE)AMINO)-OXY)CARBONYL)AMINO)THIO) CARBAMIC ACID, ETHYL ESTER mf C10H17N3O5S2 mw 323.42 SAFETY PROFILE A poison by ingestion. When heated to decomposition it emits toxic vapors of NOx and SOx. 

Hydroxy-4-methyl-5 thiazolecarboxyhc acid ethyl esters, from a-chloro-acetoacetate and ammonium thio-carbamate, 258... 

Sulfur as a Base. Evidence that the sulfur atom can act as a base in H bonding has been offered for diethylammonium diethyldi-thiocarbamate (238), ethylenethiourea (2165), thioamides (668), thio-carbamic acids (325, 955), disulfides (359), and 2-thiopyridone (1607). 

Thio-carbamic acid ester Alkyl thio-urea... 

The product, methyl ammonium methyl di-thio-carbamate, is an alkyl ammonium salt, corresponding to the ammonium salt, of methyl di-thio-carbamic acid as shown by the following formulas ... 

Similar transformations can be achieved from y-methylthioallyl thiocarbamates or from allyl thio-carbamates (Scheme 32, entries c and d). Both reaction sequences take advantage of the easy sigma-tropic rearrangement of allyl thiocarbamates. Furthermore, -methoxyallyl thiocarbamates have played the role of an acetone enolate (Scheme 32, entry a). - ... 

In essence, this identifies the rhamnosylated 4-hydroxy-benzyl isothiocyanates, carbamates and thiocarbamates as the pharmacologically active principles of the extracts. The effects of all of these compounds have been found to be similar, reversible and dose-dependent. Nitriles do not show any hypotensive effect however. Investigations on organs of several animals indicate spasmolytic properties of thiocarbamates in vitro along with the hypotensive effects (29). Nevertheless, with these studies no specific mechanism can be supposed for the hypotensive and spasmolytic effects of these thio-carbamates (57). 

Low molecular weight carbamate, thio-carbamate, and thiourea derivatives. 

Schuphan, I. and Casida, J. E. (1979). S-chloroallyl thio-carbamate herbicides Chemical and biological formation... 

The equilibrium mixture of these two compounds can be directly used for the preparation of sugar-derived thioureas by coupling with alkyl and aryl amines [47]. This was the first example in the literature of a thio carbamate acting as a latent isothiocyanate for the synthesis of thioureas. 

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