Thiols, Thioethers

Thiols, thioethers, disulfides Sodium metaperiodate + benzidine Substances with divalent sulfur yield white chromatogram zones on a blue background. [36]... 

Thiols, thioethers and sulfoxides [37-39] e.g. sulfur-containing amino acids... 

Tc(V) and Re(V) are thiols, thioethers and thiocarbonyl compounds and molecules containing combinations of their functional groups. There exist significant differences in the ability of the various groups to form stable complexes and in the kind of complexes formed. Unlike thiols, a neutral S-donor shows a preference for the metals in oxidation states lower than +5. 

SYNTHESIS OF THIOLS, THIOETHERS, THIOACETALS AND S-ALKYL THIOCARBOXYLIC ESTERS... 

As mentioned above, the grafting to technique enables in a one-pot reaction the synthesis of Au NPs stabilized by sulfur-containing polymers, which bear functional groups such as dithioester, trithioester, thiol, thioether and disulfide at the end of a polymer chain or in the middle. This method leads to nanoparticles similar to those obtained by the Brust-Schiffrin method in which alkanethiol-protected Au NPs of small size are obtained. This grafting to technique leads to very stable nanomaterials that also present a high surface graft density of polymer brush on the Au NP surface. 

Various sulfur-containing compounds, including thioamides, thioureas, thiols, thioethers and disulfides, are oxidized by this enzyme system. However, unlike cytochromes P-450, it cannot catalyze hydroxylation reactions at carbon atoms. It is clear that this enzyme system has an important role in the metabolism of xenobiotics, and examples will appear in the following pages. Just as with the cytochromes P-450 system, there appear to be a number of isoenzymes, which exist in different tissues, which have overlapping substrate specificities. 

Also, 67 can be converted to the hydrocarbon 272 on treatment with pyridine, thiols, thioethers, or thiourea. These reactions can have significance... 

In general, EC reactions are typically observed according to the following general rank order (by relative ease of oxidation) o,p-quinol and o,p-aminophenol > tertiary amine > m-quinol rv phenol rv arylamine > secondary amine thiol > thioether primary amines, aliphatic alcohols. (HDVs) each redox active metabolite are obtained from the response across adjacent EC-Array sensors. These data are a reflection of the kinetic and thermodynamic components of electron transfer reactions. Since chemical structure is a critical determinant of an analyte s redox behavior, the intrinsic generation of an HDV with EC-Array provides qualitative information for each species. 

Tables IV through IX summarize the data that are currently available on the rates of bimolecular substitution and dehydrohalogenation reactions between sulfur nucleophiles and halogenated aliphatic substrates in aqueous solution (i.e., either measured in water or extrapolated to water from a non-aqueous or partially aqueous solvent). The sulfrir nucleophiles considered in these tables are HS-, S2-, S42-, S52- (Table IV), S2032 (Tables V and VIII), SO32-, HSO3 (Table VI), thiolate anions (Tables VII, VIII, and IX), thiols, thioethers, and thioadds (Table VII).

Therefore, it is possible to convert a variety of primary and secondary alkyl halides to alcohol, ethers, thiols, thioethers, esters, amines, and azides (Following fig.). Alkyl iodides and alkyl chlorides can also be synthesised from other alkyl halides. 

From the studies reviewed above it has become evident that competion studies between thiols/thioethers and intact double-helical DNA are required, to find out whether or not the formation of the Pt-GG chelate is a driving force that can overcome the Pt-S interactions. Even then, one should realize that we are only dealing with a model, as in the cell other metals might also play a role in the disruption of Pt-S bonds. In this respect it should be mentioned that it was recently reported that addition of transition metals such as Zn11 or Cu11 can cleave even the Pt-S bond in thiolated terpyridine-platinum complexes at neutral pH [87],... 

Desulfurization (13, 158-159).1 In addition to desulfurization of thiols, thioethers, sulfoxides, and sulfones, Cp2Ni-LiAlHi (1 1) can serve as a hydrogenation catalyst for reduction of alkenes it also reduces enones to ketones, but in low yield. In general, it is similar in reactivity to Raney nickel and to (2,2 -bi-... 

Like thiols, thioethers have strong characteristic odors The odor of dimethyl sulfide is reminiscent of oysters that have been kept in the refrigerator for too long. Sulfides are named like ethers, with sulfide replacing ether in the common names. In the IUPAC (alkoxy alkane) names, alkylthio replaces alkoxy. ... 

Serum albumin (bovine) Exposed thiol/thioether groups (generally) Reduction of HOC1 and chloramines oxidant-scavenging function suggested (H25, Y4)... 

Proteins contain a wide range of functional groups. These functional groups include alcohols, thiols, thioethers, carboxylic acids, carboxamides, and a variety of basic groups. Most of these groups are chemically reactive. When... 

At variance with thiols, thioether groups interact directly with the Au substrate, and the above-described protection/deprotection procedure is therefore unnecessary. In addition, they afford a more co or dinative grafting, the Au-S bond energy being ca. 60kjmol as compared with... 

Zinc bismuthate Zn(Bi03)2, readily obtained as a light brown solid from sodium bismuthate and zinc chloride, has been successfully employed for the oxidation of alcohols, thiols, thioethers and oximes (Scheme 5.8) [92BCJ1131, 94SC489]. The yields are comparable with or better than those of the barium permanganate and pyridinium chlorochromate oxidations. 

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