Sulphanes

In addition to the hydrides of formula HjX, oxygen forms the hydride H2O2, hydrogen peroxide, and sulphur forms a whole series of hydrides called sulphanes. These are yellow liquids which are thermodynamically unstable with respect to hydrogen sulphide and sulphur. 

Westley, J. 1988. Mammalian cyanide detoxification with sulphane sulphur. Pages 201-218 in D. Evered and S. Harnett (eds.). Cyanide Compounds in Biology. Ciba Found. Sympos. 140. John Wiley, Chichester. Wiemeyer, S.N., E.F. Hill, J.W. Carpenter, and A.J. Krynitsky. 1986. Acute oral toxicity of sodium cyanide in birds. Jour. Wildl. Dis. 22 538-546. 

In our group, the tin-lithium exchange has been used to synthesize the doubly lithiated dimethyl sulphane 99 by the reaction of bis(tributylstannomethyl)sulphane (98) with two equivalents of n-butyllithium in diethyl ether". Two equivalents of tetrabutylstannane are cleaved off in this reaction (Scheme 34). 

Ogata, M., Noro, Y., Yamada, M.,Tahara,T., and Nishimura,T. (2000), Photo-degradation products of methylprednisolone sulphanate in aqueous solution—Evidence of a bicyclo[3.1.0]hex-3-en-2-one intermediate,/. Pharm. Sci., 87(1), 91-95. 

Fundamental thermodynamic and kinetic studies of the decomposition reaction (1) have confirmed that hydrogen sulphide is a stable sulphide and that the dissociation is thermodynamically unfavorable below 1800°K. Nevertheless, some decomposition does, of course, occur below these temperatures and equilibrium hydrogen yields range from less than 1% at 750°K through about 5% at 1000°K to almost 30% at 1400°K. [These values are based on equilibrium product calculations which considered all possible sulphur/hydrogen species which could be present at equilibrium including various sulphur vapor species (S S to S ), and sulphanes (H2Sx) as well as H2S, H and The values which are... 

Westley, J. (1981) Cyanide and sulphane sulfur, in Cyanide in Biology (eds B. Vennes-land, E.E. Conn, C.J. Knowles, J. Westley and R Wissing). Academic Press, London, pp. 61-76. 

Gimenez J, Botella-Estrada R, Hernandez D, Carbonell M, Martinez MA, Guillen C, Vazquez C. Anaphylaxis after peritumoral injection of sulphan blue 1% for identification of the sentinel node in lymphatic mapping of the breast. Eur J Surg 2001 167(12) 921-3. 

Cyclo-octasulphur monoxide was first obtained as a product of the reaction of thionyl chloride with crude sulphane, H2Sn. It has now been found that S8 may be oxidized directly with trifluoroperacetic acid (molar ratio 1 1) in a simple manner 53... 

Starting from mixtures of sulphanes and chlorosulphanes, the new sulphur ring compounds S18 and S20 have been synthesized by the reaction 56... 

Several methods for the preparation of CF3SSC1, chloro(trifluoromethyl)-disulphane, have been reported.73 Under photolytic conditions, bis(tri-fluoromethyl)disulphane reacts with either sulphur dichloride or dichlorodi-sulphane to produce small quantities of CF3SSC1. The former reaction appears to proceed via formation of S2C12, accompanied by large amounts of CF3SC1 as a by-product. The reaction of trifluoromethanethiol with sulphur dichloride at ambient temperatures is probably the best method, giving yields of the disulphane between 60 and 70% ... 

The selenium-sulphur compound Se Si2 has been prepared280 by the reaction of SeCl4 or Se2Cl2 with crude sulphane. A structure determination, using crystals containing 26% selenium, showed that two of the four independent point positions of the Si2 ring are occupied by sulphur atoms, and the two others are occupied by selenium and sulphur at 25 and 75%, respectively. The analytical and structure determinations also showed the existence of a solid solution between the phase which is probably Se2Si0 and S,2. 

Okoh and Pitt, 1982 Silver et al., 1982). Thus, rat LD50 values for NaCN by the peroral (po) and intraperitoneal (ip) routes are respectively 5.7 and 4.72 mg kg-1, and the corresponding values for NaSCN are 764 and 540 mg kg-1 thus, the conversion of NaCN to NaSCN results in a decrease in acute lethal toxicity by a factor of about 120-fold in the rat (Ballantyne, 1984). SCN is renally excreted with a half-life of 2.7 days in healthy subjects (Schulz et al., 1983). Two enzyme systems are responsible for the transulphuration process (Ballantyne, 1987b Lang, 1933 Sorbo, 1975) thiosulphate-cyanide transulphurase (EC 2.8.1.1 rhodanese) and (3-mercaptopyruvate-cyanide transulphurase (EC 2.8.1.2). Thiosulphate-cyanide transulphurase is a mitochondrial enzyme that catalyzes the transfer of a sulphane sulphur atom from sulphur donors to sulphur acceptors ... 

The basic reaction involves transfer of sulphane sulphur from the donor (SCN) to the enzyme, forming a persulphide intermediate. The persulphide sulphur is transferred from the enzyme to a nucleophilic receptor (CN) to yield SCN. Although the enzyme activity varies between species and tissues, it is high for most species in liver, kidney and olfactory mucosa (Dahl, 1989 Himwich and Saunders, 1948). The nasal metabolism of CN may have a significant relevance to the toxicity of inhaled HCN. 

There is evidence that the thiosulphate sulphur-transferase system may not necessarily be the primary simplistic detoxification mechanism for CN as outlined briefly above, principally because little SCN penetrates the inner mitochondrial membrane to access the transferase system. A more general view of the role of sulphur in the detoxification process is that the supply of sulphane sulphur is from a rapidly equilibrating pool of potential sulphane sulphur donors, and these... 

There is evidence for the possible participation of a third sulphurtransferase, cystathionase (cystathionine y-lyase EC 4.4.1.1), a cytosolic enzyme, in CN detoxification in the kidney and rhombencephalon (Wrobcl et al., 2004). A product of the y-cystathionase reaction, bis(2-amino-2-carboxylethyl)trisulphide(thiocystine), may serve as a sulphur substrate donor for rhodanese. Another product of the reaction, 3-(thiosulpheno)-alanine (thiocysteine), may be an additional link between y-cystathionase and CN biodetoxification. In addition to its function of generating sulphane sulphur compounds, y-cystathionase also functions as a sulphane sulphur carrier. 

Sulphan Blue C27H3- N2NaOeS2 129-17-9 666.664 viol pow sFtOH... 

Equimolar amounts of SClg and SgClg have been shown to react with phenylperthiophosphonic anhydride (13) to yield, quantitatively, bis(phenyl-chlorothiophosphoryl)-tri- (14) and -tetra-sulphane (15), respectively. The... 

Crystals of SgO, produced by condensation of SOClg with crude sulphane (H2S , n = 3, 4, or 5) and recrystallization from CSg, have been shown to belong to the space group Pcfl2, with a = 13.197,= 7.973,andc = 8.096 A. The molecule SgO belongs to the point group C, the sulphur atoms form a crown-shaped ring (43) in which each set of four atoms lies approximately in... 

The kinetics of H2S dissociation reaction were studied extensively [3, 4, 7, 59-64]. Although the decomposition to S2 and H2 has often been used as the representative reaction, other sulphur aUotropes, sulphanes and HS are also formed and need to be considered, especially at lower temperature, as recognized by Raymont [3]. Detailed high-temperature kineties of H2S deeomposi-tion pertinent to forward and reverse part of the reaetion were reported by Kaloidas et al. [4] and Dowling et al. [59], respectively. Although the estimated... 

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