Sulfur compounds derivatives

Petroleum Companies. Some of the major petroleum companies are carrying on extensive research programs on problems associated with the presence of sulfur in petroleum and as a product of this research some information on the availability of sulfur compounds derivable from petroleum has been obtained. While much of this information is of necessity confidential, some portion of it is eventually presented at American Chemical Society meetings or is published in the chemical literature. Although no attempt can be made to name all the companies carrying on work of this sort, there have been recent contributions by research workers from Phillips Petroleum Company, Standard Oil Development Company, Anglo-Iranian Oil Company, Union Oil Company, and Standard Oil Company (Indiana). 

Traditionally fermented dairy products have been used as beverages, meal components, and ingredients for many new products [60], The formation of flavor in fermented dairy products is a result of reactions of milk components lactose, fat, and casein. Particularly, the enzymatic degradation of proteins leads to the formation of key-flavor components that contribute to the sensory perception of the products [55], Methyl ketones are responsible for the fruity, musty, and blue cheese flavors of cheese and other dairy products. Aromatic amino acids, branched-chain amino acids, and methionine are the most relevant substrates for cheese flavor development [55]. Volatile sulfur compounds derived from methionine, such as methanethiol, dimethylsulflde, and dimethyltrisul-fide, are regarded as essential components in many cheese varieties [61], Conversion of tryptophan or phenylalanine can also lead to benzaldehyde formation. This compound, which is found in various hard- and soft-type cheeses, contributes positively to the overall flavor [57,62]. The conversion of caseins is undoubtedly the most important biochemical pathway for flavor formation in several cheese types [62,63]. A good balance between proteolysis and peptidolysis prevents the formation of bitterness in cheese [64,65],... 

Gypsum (calcium sulphate) is the main mineral in wredlboard. Sulfur compounds derived from petroleum are used to make many industrial compounds such as sulphuric acid. 

Kyung KH, Fleming HP (1997) Antimicrobial activity of sulfur compounds derived from cabbage. J Food Prot 60 67-71... 

Kyung KH, Lee YC (2001) Antimicrobial activities of sulfur compounds derived from S-alk (en) yl-L-cysteine sulfoxides in Allium and Brassica. Food Rev Int 17 183-198 Lee YS, Kang OH, Choi JG, Oh YC, Keum JH, Kim SB, Jeong GS, Kim YC, Shin DW, Kwon DY (2010) Synergistic effect of emodin in combination with ampicillin or oxacillin against methicUlin-resistant Staphylococcus aureus. Pharm Biol 48 1285-1290 Li Y, Du Y, Zou C (2009) Effects of pH on antioxidant and antimicrobial properties of tea saponins. Eur Food Res Technol 228 1023-1028... 

Kurt S, Gunes U, Soylu EM (2011) In vitro and in vivo antifungal activity of synthetic pure isothiocyanates against Sclerotinia sclerotiorum. Pest Manag Sci 67 869-875 Kyung KH, Fleming HP (1997) Antimicrobial activity of sulfur compounds derived from cabbage. J Food Prot 60 67-71... 

The term naphthenic acid, as commonly used in the petroleum industry, refers collectively to all of the carboxyUc acids present in cmde oil. Naphthenic acids [1338-24-5] are classified as monobasic carboxyUc acids of the general formula RCOOH, where R represents the naphthene moiety consisting of cyclopentane and cyclohexane derivatives. Naphthenic acids are composed predorninandy of aLkyl-substituted cycloaUphatic carboxyUc acids, with smaller amounts of acycHc aUphatic (paraffinic or fatty) acids. Aromatic, olefinic, hydroxy, and dibasic acids are considered to be minor components. Commercial naphthenic acids also contain varying amounts of unsaponifiable hydrocarbons, phenoHc compounds, sulfur compounds, and water. The complex mixture of acids is derived from straight-mn distillates of petroleum, mosdy from kerosene and diesel fractions (see Petroleum). 

Tricyclic Antidepressants. Imipramine [50-49-7] (32), which was the first tricycHc antidepressant to be developed, is one of many useful psychoactive compounds derived from systematic molecular modifications of the antihistamine prometha2ine [60-87-7] (see Histamine and histamine antagonists). The sulfur atom of prometha2ine was replaced with an ethylene bridge and the dimethylamino group attached to an / -propyl group, rather than to an isopropyl one, of the side chain. The actual synthesis of (32) is typical of the compounds in this class (37). 

Other miscellaneous compounds that have been used as inhibitors are sulfur and certain sulfur compounds (qv), picryUiydrazyl derivatives, carbon black, and a number of soluble transition-metal salts (151). Both inhibition and acceleration have been reported for styrene polymerized in the presence of oxygen. The complexity of this system has been clearly demonstrated (152). The key reaction is the alternating copolymerization of styrene with oxygen to produce a polyperoxide, which at above 100°C decomposes to initiating alkoxy radicals. Therefore, depending on the temperature, oxygen can inhibit or accelerate the rate of polymerization. 

The tautomerism of 2-substituted 1,3-azoles (154 155) is summarized in Table 39. Whereas amino compounds occur Invariably as such, all the potential hydroxy derivatives exist in the 0x0 form, and in this series the sulfur compounds resemble their oxygen analogs. There is a close analogy between the tautomerism for all these derivatives with the corresponding 2-substltuted pyrldines. 

The salt K2[SN2] is an important reagent for the preparation of other sulfur diimide derivatives when MesSiNSNSiMes is not sufficiently reactive. For example, both acyclic and cyclic arsenic(Iir) compounds, Bu2AsNSNAs Bu2 and BuAs(NSN)2As Bu, respectively, have been obtained in this way." ... 

Sulfur compounds exhibit a rich and multifarious variety which derives not only from the numerou.s possible oxidation states of the element (from —2 to 4-6) but also from the range of bond types utilized (covalent, coordinate,... 

Heteroaromatic sulfur compounds do form sulfoxides and sulfones, but these derivatives have their own special reactivity. Francesca Clerici (Milan, Italy) has now provided an up-to-date survey of the preparation and properties of the S-oxides of thiazoles and thiadiazoles, collecting literature scattered in many publications. 

Sulfoxides (R1—SO—R2), which are tricoordinate sulfur compounds, are chiral when R1 and R2 are different, and a-sulfmyl carbanions derived from optically active sulfoxides are known to retain the chirality. Therefore, these chiral carbanions usually give products which are rich in one diastereomer upon treatment with some prochiral reagents. Thus, optically active sulfoxides have been used as versatile reagents for asymmetric syntheses of many naturally occurring products116, since optically active a-sulfinyl carbanions can cause asymmetric induction in the C—C bond formation due to their close vicinity. In the following four subsections various reactions of a-sulfinyl carbanions are described (A) alkylation and acylation, (B) addition to unsaturated bonds such as C=0, C=N or C= N, (C) nucleophilic addition to a, /5-unsaturated sulfoxides, and (D) reactions of allylic sulfoxides. 

It is well estabhshed that sulfur compounds as well as elemental sulfur have the tendency to form long chain molecules. All of these substances can be regarded as derivatives of the hydrogen polysulfanes (or polysulfanes) H2S . Polysulfanes form a long series of homologous chain-like molecules since the number n can assume any value. S-S and S-H bonds are frequently found in chemical and biological systems. Thus, polysulfanes have been the subject of numerous experimental and theoretical studies (for a recent review, see [15]). 

Sulfonates, aliphatic la 388, 389 Sulfones lb 321,360 Sulfonic acids la 91 Sulfonylurea derivatives lb 204 Sulfoxides lb 321,358,360,372,373,374 Sulfur compounds lb 338 Sulfur-containing compounds lb 301,339 Sulfur dioxide vapor la 86 -, dipole moment la 97 Sulfur, divalent lb 302 Sulfuric acid la 87,195,333,411,426 Sulfur ions lb 302 Sulfutyl chloride vapor la 86 Sulpyrid lb 268 Sunflower seed oil lb 286 Surfactant-TLC plates la 89 Sweeteners la 44, 388-390 Swep la 108... 

Sulfur in cmde oil is mainly present in organic compounds such as mercaptans (R-SH), sulfides (R-S-R ) and disulfides (R-S-S-R ), which are all relatively easy to desulfurize, and thiophene and its derivatives (Fig. 9.2). The latter require more severe conditions for desulfurization, particularly the substituted dibenzothiophenes, such as that shown in Fig. 9.2. Sulfur cannot be tolerated because it produces sulfuric add upon combustion, and it also poisons reforming catalysts in the refinery and automotive exhaust converters (particularly those for diesel-fueled cars). Moreover, sulfur compounds in fuels cause corrosion and have an unpleasant smell. 

Sulfur compounds are useful as nucleophilic acyl equivalents. The most common reagents of this type are 1,3-dithianes, which on lithiation provide a nucleophilic acyl equivalent. In dithianes an umpolung is achieved on the basis of the carbanion-stabilizing ability of the sulfur substituents. The lithio derivative is a reactive nucleophile toward alkyl halides and carbonyl compounds. 11... 

In a report comparing community responses to low-level exposure to a mixture of air pollutants from pulp mills, Jaakkola et al. (1990) reported significant differences in respiratory symptoms between polluted and unpolluted communities. The pollutant mixture associated with the pulp mills included particulates, sulfur dioxide, and a series of malodorous sulfur compounds. Major contributors in the latter mixture include hydrogen sulfide, methyl mercaptan, and methyl sulfides. In this study the responses of populations from three communities were compared, a nonpolluted community, a moderately polluted community, and a severely polluted community. Initial exposure estimates were derived from dispersion modeling these estimates were subsequently confirmed with measurements taken from monitoring stations located in the two polluted communities. These measurements indicated that both the mean and the maximum 4-hour concentrations of hydrogen sulfide were higher in the more severely polluted community (4 and 56 g/m3 2.9 and 40 ppb) than in the moderately polluted one (2 and 22 g/m3 1.4 and 16 ppb). Particulate measurements made concurrently, and sulfur dioxide measurements made subsequently, showed a similar difference in the concentrations of these two pollutants between the two polluted communities. 

Thiophenolate complexes have been discussed, however, a considerable amount of alkylthiolate zinc chemistry is also known. The zinc alkylthiolate complexes with methanethiolate, ethanethiolate, and /. so-propylthiolate have been synthesized and characterized as precursors for ZnS formation. Thermolysis studies demonstrated the formation of ZnS and release of dimethylsulfide. Reactivity was similar with only the rm-propyl derivative showing much slower reaction.523 The polyzincate Zni0S4(SEt)i2L4 is a well-characterized neutral zinc sulfur compound.524... 

Let us now discuss some of the characteristics of this quenching with mercaptans and disulfides. Interestingly, both sulfur derivatives are equally effective in inhibiting the photoreduction and are in fact interconverted during the reaction. The same equilibrium mixture of mercaptan and disulfide is obtained regardless of which was initially added to the reaction mixture. Furthermore, there appears to be no appreciable consumption of the sulfur compounds/64 When benzophenone is irradiated in the presence of isopropanol (OD) and mercaptan, isopropanol containing two deuterium atoms is isolated,... 

Further development in the area of alternate value-added products for improving economics included other oxygenated sulfur compounds [246,247], This invention included alkylated 2-(2-hydroxyphenyl) benzenesulfinic acid and 2-(2-hydroxyphenyl)-benzenesulfonic acid compounds and compositions which consist essentially of 2-(2-hydroxyphenyl) benzenesulfinic acid, 2-(2-hydroxyphenyl)-benzenesulfonic acid and/or substituted derivatives. The compositions are useful as hydrotropes and are also of use as, or as starting materials for, surfactants, and as starting materials for the synthesis of other useful chemicals such as, polymers and resins, solvents, adhesives, and biocides. 

Recently, several thermophilic organisms have been reported to be capable of sulfur-specific biodesulfurization. These include the Paenibacillus [87,151], Mycobacterium [30,31,85,94,294,295], etc. The ability to desulfurize sulfur compounds other than DBT derivatives, including benzothiophene, naphthothiophene, and benzonaphthothio-phene derivatives has also been demonstrated, thus widening the substrate specificity of the biodesulfurization process. Second, the thermophilic ability of the organisms offers temperature and operational advantages to further improve the commercialization potential of the BDS process. 

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