Sulfate ester-containing compounds

Detoxifica.tlon. Detoxification systems in the human body often involve reactions that utilize sulfur-containing compounds. For example, reactions in which sulfate esters of potentially toxic compounds are formed, rendering these less toxic or nontoxic, are common as are acetylation reactions involving acetyl—SCoA (45). Another important compound is. Vadenosylmethionine [29908-03-0] (SAM), the active form of methionine. SAM acts as a methylating agent, eg, in detoxification reactions such as the methylation of pyridine derivatives, and in the formation of choline (qv), creatine [60-27-5] carnitine [461-06-3] and epinephrine [329-65-7] (50). 

Identification of N-, P-, and S-containing compounds is difficult, and those that are identified tend to be metabolic products, such as nucleotides and vitamins, released into the soil following the death of cells. Broadly, nitrogen is an integral part of the humic molecule, and is released as NH4 ions when the humic material is degraded. Phosphorus and sulfur are more commonly found as P and S esters, which can be released as orthophosphate and sulfate ions by the action of phosphatase and sulfatase enzymes, respectively. 

These compounds are permanently anionic and are moderately polar (surfactants are organic molecules that are surface active). This means that they concentrate on the surface of a liquid in which they are dissolved. Generally, these types of analytes contain both a hydrophobic and a hydrophilic segment. There are anionic, cationic, neutral, and amphoteric surfactants. They may be readily sorbed from water by reversed-phase SPE. Elution requires methanol or acetonitrile rather than ethyl acetate because of their polar, ionic functional groups, which are typically sulfate esters or sulfonic acids (Fig. 7.18). 

Many marine organisms contain compounds that possess a sulfate ester functionality. These compounds tend to be active in a number of receptor binding and enzyme bioassays and can often be difficult to purify. They tend to occur as a series of closely related compounds that are both very polar and labile to acid or base treatment. Perhaps the most commonly occurring sulfate ester is halistanol sulfate (Scheme 5), first reported from Halichondna cf moorei (34). 

Another class of compound that can be difficult to purify is the saponins found in Echinoderms. Almost all echinoderms examined to date contain either polyhydroxylated sterols or terpene glycosides, many of which contain sulfate ester functionality. The purification of compounds (Schemes 6-9) (40) from the starfish Nardoa tuberculata exemplifies the procedure most often used to purify these metabolites (Fig. 2). 

Compounds of this set to have been prepared are 46, a core fucosylated, bianten-nary N-glycan with a novel GlcNAc residue in the core region, 47, a Sia Le containing compound with and without a sulfate ester at 0-6 of the GlcNAc residue, and 48 made by chemoenzymic methods and linked to a fluorophore to provide means of visualization of cell-surface selectively bound SiaLe compounds. ... 

Sulphur was found through spark source mass spectrometry to be abundant in SRS-A [93], Also, incorporation of S into SRS has been reported [64,94-96], The observation that several thiols enhance SRS formation in different systems [97-100] and that arylsulfatase (an enzyme that cleaves sulfate monoesters of phenolic and other unsaturated hydroxylated systems) inactivates SRS-A [101,102] opened the view that a thiol is a constituent of the active compound. However, it has recently been shown that the SRS-inactivating action of commercially available arylsulfatase is not due to sulfate ester cleavage, but to a dipeptidase contaminant [103,104]. The destruction of different SRS compounds by hpoxygenase [67,105,106] shows that SRS contains a cij,c/s-1,4-pentadiene structure, since this is a prerequisite for a lipoxygenase substrate [107], For a review of the earlier structural work on SRS, see ref. 108. 

SuMur compounds compounds containing reduced or oxidized sulfur, seldom both (Table). Biochemically important S.a are the sulfur amino adds (see L-C eine, L-Methionine), biotin (thiophane ting) and thiamin (thiazole ting) (see Vitamins), sul-fatides (complex lipids of the nervous system see dy-colipids), and thiol peptides (see Glutathione, Vasopressin, Oxytodn, Insulin). S.c. also include Penicillin (see), and the sulfonamid which are important synthetic therapeutic agents. Hie mustard oil glycosides contain both oxidiz and reduced sulfur. Sulfate esters (see) are excreted by animals. 

Chemical formula of saxitoxin 16 is C10H17N7O4 and that of tetrodotoxin 17 is CnHi7N30g. Both compounds are water soluble because of their ionic structures. There are many saxitoxin-related compounds which contain additional sulfate ester and/or sulfocarbamoyl moieties. In the case of tetrodotoxin, numerous analogues have been isolated from a variety of aquatic animals including puffer fish, newts, frog, and octopus [32]. 

The most successful of these products contain high ratios of VP to DMAEMA and are partially quatemized with diethyl sulfate (Polyquaternium 11) (142—144). They afford very hard, clear, lustrous, nonflaking films on the hair that are easily removed by shampooing. More recendy, copolymers with methyl vinyl imidazoliiim chloride (Polyquaternium 16) (145) or MAPTAC (methacrylamidopropyltrimethyl ammonium chloride) (Polyquaternium 28) have been introduced. Replacement of the ester group in DMAEMA with an amide analog as in Polyquaternium 28 results in a resin resistant to alkaline hydrolysis and hence greater utility in alkaline permanent-wave and bleach formulations (see Quaternary ammonium compounds). 

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