Glycerol ether esters

Uses. Stabilizer in the manufacture of vinyl polymers chemical intermediate in preparation of glycerol, glycidyl ethers, esters, and amines in pharmaceuticals in sanitary chemicals... 

In 1956, glycidol was only used for research purposes (Hine et al., 1956), but by 1978 it was used in the preparation of glycerol, glycidyl ethers, esters and amines in the pharmaceutical industry (Proctor Hughes, 1978) and as a sterilant in pharmaceuticals (Ivashkiv Dunham, 1973). 

Carnahan, M. A., and Grinstaff, M. W. 2001b. Synthesis and characterization of poly-ether-ester dendrimers from glycerol and lactic acid. J. Am. Chem. Soc., 12, 2905-2906. 

More commonly, waxes are esters of an alcohol other than glycerol (long chain alcohol, sterol, hydroxycarotenoids, vitamin A) and a long chain acid (wax esters). Wax esters are saponified by hot alkaline solutions and give a fatty acid and an alcohol. They are soluble in aromatic solvents, chloroform, ethers, esters and ketones. 

A new synthetic substrate (l,2 0-dilauryl-rac-glycero-3-glutaric acid-(4-methyl-resorufin)-ester), consisting of two glycerol ether and one ester bonds, has been proposed. LPS hydrolyze the latter bond in an alkaline medium to an unstable dicarbonic acid ester that spontaneously hydrolyzes to yield glutaric acid and methylresorufin this is a bluish-purple chromophore with peak absorption at 580 nm. 

The composition of membranes in the archaea is remarkably different from both bacteria and the eukaryotes. Instead of the straight-chain fatty acids linked to glycerol through ester bonds that are typically found in the lipids that comprise membranes, the hydrocarbon chains in the membranes of the archaea are linked by ether linkages. In addition, archaean membrane lipids also contain some branched-chain hydrocarbons. 

Important distinguishing features between eubacteria and A. are the cell wall structures of A. are heterogeneous (pseudomurein, proteins, glycoproteins, heteropolysaccharides), all A. lack muramic acid, a typical building block of the eubacterial cell wall. Thus, various antibiotics (e. g. penicillin, chloramphenicol) do not exhibit any inhibitory action. The cytoplasm membranes contain glycerol ethers with Cjo- and C4o-iso-prenoids instead of fatty acid glycerol esters. In addition to special biosynthetic pathways and unusual co-... 

Ethers, Esters, and Ether Esters of Glycerol and Various Diols... 

Baumann and Ulshofer (1968) have recorded and interpreted spectra of long-chain ethers, esters, and ether esters of glycerol, 1,2-ethanediol, and propanediols. They have discussed the influence of the environment of alkoxy, acyloxy, and hydroxy groups on the absorption frequencies of these functional groups. 

Glucoside alkyl ethers Polyoxyethylene glycol octylphenol ethers Polyoxyethylene glycol alkylphenol ethers Glycerol alkyl esters... 

Ester or lipid hydrolysis is most conveniently effected in the laboratory by refluxing with aqueous ethanolic alkali. Acidification of the hydrolysate liberates fatty acids which can be extracted with hexane or other organic solvent. Non-acidic compounds (unsaponi-fiables) such as hydrocarbons, long-chain alcohols, sterols and glycerol ethers will also be present in the organic extract, but glycerol remains in the aqueous phase. The hydrolysis may be effected quantitatively for determination of saponification equivalent or saponification value (Section 6.2.10). 

Glycerol ethers, AG-OCH2CH(OH)CHjOH Butyl ethers, AG-OCHjCHjCHjCHj Benzyl ethers, AG-OCH2C5H5 Ethoxylates, AG-O(CH2CH20),H Carboxylic acid esters, AG-OC(=0)(CH2)xH Ethyl carbonates, AG-OC(=0)OC2Hj Anionic alkyl glucoside derivatives Sulfates, AG-OSO3-... 

Diol lipids have recently been detected in maize oil (seed oil from Zea mays) with the help of chromatographic methods [12]. It was evident that adsorption TLC was not capable of separating the esters and alkenyl ether esters of diols from the corresponding glycerol derivatives [12] (see also [22] and [9]). Using TLC, it was nevertheless possible to fractionate the products of alkaline methanolysis of the triglycerides of maize oil into three fractions methyl esters, alkenyl ethers and polyhydric alcohols. The alcohols could be separated and identified as their acetates by gas chromatography [12]. 

Esters of long-chain fatty acids with ethanediol and other diols occur in beef lung [22], beef suet and pig lard [22] and in rat liver [12], Diesters, ether esters and dialkyl ethers of ethanediol cannot be separated from the corresponding glycerol derivatives through adsorption TLC but this separation succeeds with reversed phase partition TLC [9]. 

The ether linkage in glycerol ethers is stable to both acidic and basic hydrolysis, although the ester bonds are readily hydrolysed as in all glycerolipids. 

Recently, new poly(ether ester) polyols were synthesized by epoxidation, followed by hydroxylation and transesterification with 1,3-propanediol and 1,2-propanediol (Kong et al., 2011,2012) (Fig. 3.3). This reaction has the peculiarity of yielding polyols which do not contain the glycerol backbone. The hydroxyl number of these polyols ranges from 270 to 320mgKOH/g. 

The fundamental character of these glycerol ethers lies in the configuration of the central carbon of glycerol. This is sn-2,3 for the ethers encountered in Archaea, and sn-1,2 for esters present in the membranes of Eubacteria (prokaryotic) and Eukaryotes. Figures 6.1 and 6.2 present some examples of these structural variations for the diethers and the tetraethers, respectively. 

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