Alkyl diglycerides

Fig. 132. Analysis of the eluate fractions of a column-chromatographic separation of Hydrolagus colliei liver oil. I neutral plasmalogens II alkyl diglycerides III triglycerides (cf with Fig.. 131, No. 2)...

Two groups have reported that lipid extracts of mouse tumours contain compounds which riiigrate ahead of the triglyceride fractions on adsorbent layers [113, 191] these substances were considered at first to be methyl esters of fatty acids but more detailed studies of the material isolated through TLC, showed that they were alkyl diglycerides [191]. 

Fig. 136. Isolation of neutral plasmalogens and alkyl diglycerides from the human perinephrium [181]. Adsorbent silica gel G solvent hexane-diethyl ether (99 + 5), double development times of run 40 min each visualisation carbonisation by heating with chromic acid/sulphuric acid, a lipid extract 6 first concentration stage c second concentration stage d third concentration stage e neutral plasmalogens / alkyl diglycerides...

Myelin galactolipid analysis by HPLC. Fig. 2 and 3 show HPLC chromatograms obtained from myelin lipids on Silica column and reverse phase column, respectively. Reverse phase HPLC of mono-galactosyl diglyceride and its 1-0-alkyl ether homolog was not examined but typical chromatograms of these lipids obtained from calf brain stem were presented previously (11 ). Myelin was obtained from 25 day-old rat brains. 

Lipids are fats and oils. Fats exist as solids while oils exist as liquids at room temperature. Lipids are mainly composed of triglycerides, but may also contain steroids, phospholipids, fatty acids, monoglycerides, diglycerides and other amphi-pathic molecules with long alkyl chains. The intramolecular order of these molecules is largely determined by the conformational order of the alkyl chain. The conformational order is dependent on many factors such as chain length, temperature,... 

Transesterification of triglycerides can be facilitated by both Br0nsted acid and base catalysts [204, 205]. Essential steps over each catalyst types are shown in Scheme 6.30 and Scheme 6.31, respectively. Reaction over acid catalysts first requires triglyceride adsorption, whereas the reaction over base catalysts is initiated by alcohol adsorption. Thereafter, the carbonyl moiety in the glyceride molecule is attacked to produce the alkyl esters. These steps occur consecutively to form the diglyceride and monoglyceride esters, with three molecules of fatty acid alkyl esters produced for every molecule of glycerol. 

The alkyl glycerol ethers, alkenyl glycerol ethers and monoglycerides can occur as a- and j8-isomers diglycerides may be symmetrical (a,a -) or asymmetrical (a,jS-). 

With mono- or diglyceride sulphate. Acid hydrolysis (section 2.4.3), then as for alkyl sulphates, etc., above, or... 

Bass, DA, McPhail, LC, Schmitt, ID, Morris-Natschke, S, McCall, CE and Wykle, RL (1988) Selective priming of rate and duration of the respiratory burst of neutrophils by 1,2-diacyl and 1 -O-alkyl-2-acyl diglycerides. Possible relation to effects on protein kinase C. Journal of Biological Chemistry, 263, 19610-19617. 

The choice of pharmaceutical cosurfactants is challenging, as most of the cosurfactants utilized in fundamental research are not suitable due to bioincompatibility issues. Amongst the pharmaceutically acceptable cosurfactants are ethanol [24] medium chain mono and diglycerides [25-28], 1,2-alkanediols [29,30] and sucrose ethanol mixtures [31] alkyl monoglucosides, and geraniol [32]. 

Acetic acid, decyl ester, branched. See CIO alkyl acetate Acetic acid, esters wHh lanolin alcohols. See Acetylated lanolin alcohol Acetic acid esters of mono- and diglycerides Acetic acid esters of mono- and diglycerides of fatty acids. See Acetylated mono- and diglycerides of fetty acids... 

Sodium C9-22 alkyl sec sulfonate Sodium laureth-13 carhoxylate and diglycerides STEOL 4N... 

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