3H-l,2-dithiol-3-thione

Carbon disulfide can act as an electrophilic agent with enamines at room temperature. Therefore, treatment of an enamine with both elemental sulfur and carbon disulfide in a polar solvent can result in the formation of a 3H-l,2-dithiole-3-thione (such as 108) and/or a 2H-l,3-dithiole-2-thione (such as 109) (135,139,140). These products are the result of competing... 

From the reactions of sulfur and carbon disulfide with cyclic ketone-derived enamines (570-573) 3H-l,2-dithiole-3-thiones were obtained, whereas the addition of carbon disulfide to other enamines gave a-dithio-pyrones (574), through initial dimerization of the enamine. 

Amides such as DMF or ureas such as N,N-tetramethylurea react with bis(trimethylsilyl)selenide 604 in the presence of BF3-OEt2 to give selenoamides, for example 617, or selenoureas whereas esters such as n-butyl benzoate react with 604 in the presence of Bp3-Et20 and 2,3-dimethylbutadiene to give 619 via 618 [157]. On heating with P4Sio/sulfur and hexamethyldisiloxane 7 y9-ketoesters such as ethyl acetoacetate are converted to 3H-l,2-dithiole-3-thiones such as 620 in high yields [158] (Scheme 5.51 cf. also Section 8.6). 

J. B. Guttenplan, T. E. Spratt, M. Khmelnitsky, W. Kosinska, D. Desai, K. El-Bayoumy, Effects of 3H-l,2-dithiole-3-thione, l,4-phenylenebis(methylene)sele-nocyanate, and selenium-enriched yeast individually and in combination on benzo[a]-pyrene-induced mutagenesis in oral tissue and esophagus in lacZ mice, Mutat. Res., 559 (2004), 199 D210. 

H-l,2-Dithiole-3-thiones The treatment of )3-oxodithioic acids with H2S and bromine leads to the heterocyclic compounds. Bromine serves as an agent for the oxidative cyclization. 

In order to determine the exact mechanism, structure-activity studies were performed OPZ and 5-(4-methoxyphenyl)-3H-l, 2-dithiole-3-thione were shown to be similarly effective on the inhibition of preneoplastic lesions induced by AFBi, while treatment with 1,3-dithiole-2-thione was without effect [31]. The efficacy of OPZ compared to other dithiolethiones was further studied by evaluating the effects of 17 dithiolethiones on acute hepatotoxicity of AFBl in rats [32]. The results demonstrated that, although several dithiolethiones were more active than OPZ in inhibiting toxicity, no structural motif linked to these chemoprevention properties could be identified. 

For cyclic compounds, cyclic polysulfides 103 which contain six sulfur atoms in a ring have been reported (Fig. 21) [158]. Other heterocyclic compounds bearing dithiocarboxylate units in the ring such as l,2-dithiole-3-thiones 104 [159,160] and 5Ff-l,2,3-dithiazole-5-thiones 105 have been studied [161-165]. Some 3H -l,2-dithiol-3-thiones are found in cruciferous vegetables, and a structurally similar synthetic dithiolthione 106 called oltipraz has attracted wide interest [166-168]. Oltipraz 106 has been shown to inhibit chemically-induced... 

The chemistry associated with cyclic dithioates is varied and interesting. In particular,because 3H -l,2-dithiole-3-thiones 145 are involved in a wide varitey of biological activities, their chemistry has attracted considerable attention. A... 

S-Isopropyl and N-isopropyl groups are converted to 3H-l,2-dithiole-3-thione rings by sulfuration and chlorination with disulfur dichloride [82,83]. 

Bis(alkylthio)-3H-l,2-dithiole-3-thiones 167 can be transformed to 2,4-di-methylidene-l,3-dithietanes 168 on treatment with trialkyl phosphites [93,94] or triphenylphosphine [82]. For example, the bis(dithiacrownether) derivatives 169 have been synthesized by this reaction [93]. The reaction of 5-(alkylthio)-3ff-l,2-dithiole-3-thiones with Fischer carbene complexes gives 6-(alkylthio)-3ff-l,2-dithiine-3-thione complexes with Cr and W [95]. 

Further uses of the dimer of p-methoxyphenylthionophosphine sulphide (3, 250, 251) are the conversions of simple butyrolactones into the sulphur analogues (135) and of jS-keto-esters into 3H-l,2-dithiole-3-thiones (136) rather than the expected jS-keto-thionesters. ... 

Pyridoisothiazolones and the corresponding thiones were prepared according to Method R and used for evaluations in vitro of mti-micobacterium activity. 3H-l,2-Dithiol-[3,4-fo]pyridin-3-thione (326) was transformed into the corresponding 0x0 compound 337 (98%) with Hg(OAc)2 in AcOH [108]. The reaction of 336 with hexylamine gave the thioamide intermediate, which was then oxidised with I2 in basic conditions affording 338, which equiU-brates to 338 in different solvents such as DMSO, DMF, acetone and H2O. From 337, N-hexylisothiazolo[5,4-fo]pyridine-3-(2H)-one (339) (36%) was prepared using the sequence shown above (Scheme 83) [109]. 

Several sulphur-containing heterocyclic compounds have been found convertible into thioketones by appropriate ring-opening reactions. Thus N-(S-aryl-3H-l,2-dithiole-3-ylidene)arylamines reacted with Grignard reagents with cleavs e of the S—S bond to give the thiones (41). The thiones... 

The compounds a-4-dimethylbenzyl camphorate diethanolamine, magnesium bis (4-methoxy-y-oxo-l-naphthalenebutyrate), and 5-(p-methoxyphenyl)-l,2-dithiol-3(3H)-thione, which were supposed to be cholaneretics, did not increase the secretion of natural bile. The infrared spectra indicated that the constituion of the bile components was different after administration of each of these choleretics. The common feature of each was the near disappearance of bands of sodium taurocholate (mentioned earlier). No change in the absorption of lecithin (1738 cm ) was caused by a-4-dimethylbenzyl camphorate diethanolamine, but this band disappeared in the bile after administration of the magnesium and thione compounds above. Some bands not observed in natural bile appeared instead, notably near 1420 and 800cm, ... 

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