New Class Of Lipids Research Articles

N-alkenylpyrogallol dimethyl ethers, aliphatic diol monoesters and some minor ether lipids from Botryococcus braunii a race

From two strains of the green microalga, Botryococcus braunii (A race), we have isolated two series of very long chain n-alkenylphenols: n-alkenylpyrogallol dimethyl ethers along with the already known series of n-alkenylhydroquinol dimethyl ethers, two series of monoesters of aliphatic vicinal diols derived from alkadienes and from botryals, two new series of alkoxy ether lipids formed by oxidative coupling of two alkatrienes, and four new series of phenoxy ether lipids structurally related to an homologous series of three long chain n-alkenylresorcinols, linked by phenoxy bonds to alkenyl, botryalyl or alkylhydroquinol moieties, in the mid-chain. The structures were elucidated by spectroscopic and chemical methods. Among them, very long chain n-alkenylpyrogallol dimethyl ethers are reported for the first time from a natural source, and esters of aliphatic vicinal diols are a new class of lipids in B. braunii. By comparison with a recent report about a Bolivian strain, phenoxy ether lipids are only minor constituents.

ChemInform Abstract: Branched Long Chain Alkyl Methyl Ethers: A New Class of Lipids from Spider Silk

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Branched long chain alkyl methyl ethers: a new class of lipids from spider silk

Long chain methyl branched 1-methoxyalkanes, a new class of ether lipids, have been identified from silk of the spider Linyphia triangularis (Araneae: Linyphiidae) by use of gas chromatographic retention indices, GC/MS investigations, and chemical modifications. Methyl groups are predominantly located at C-2, and ω-3 or ω-2 positions, respectively. Chain length varies between C 24 and C 32. The synthesis of representative compounds is reported.

Rac-1,2-DIACYLOXYPROPYL-3-ARSONIC ACIDS: ARSONOLIPID ANALOGUES OF PHOSPHONOLIPIDS

Abstract A new class of lipids, arsonolipids or rac-1,2-diacyloxypropyl-3-arsonic acids, have been synthesized by acylating tetrabutyl ammonium hydrogen rac-1,2-dihydroxypropyl-3-arsonate with myristic, palmitic and stearic anhydrides in the presence of pyridine. The yields are moderate to low due to decomposition of rac-1,2-dihydroxypropyl-3-arsonic acid and its salts by acylating agents. Acid salts of arsonolipids were prepared by neutralization but neutral salts could not be made.

Cyanolipids ofCardiospermum halicacabum L. and other sapindaceous seed oils

AbstractA number of sapindaceous seed oils have been investigated with respect to their cyanolipid constituents. All but one of the oils have this new class of lipids in amounts ranging from 13% to 55%. These cyanolipids are of four different types, but all consist of long‐chain fatty acids esterified with an unsaturated isoprenoid hydroxy‐ or dihydroxynitrile. The large amounts of C20 acids usually found in these oils indicate an appreciable cyanolipid content because such acids are preferentially incorporated in nitrile‐containing fractions.Cardiospermum halicacabum L. seed oil was shown to contain 49% of a diester having two fatty acid moieties esterified with 1‐cyano‐2‐hydroxymethylprop‐2‐ene‐1‐ol and 6% of another diester derived from 1‐cyano‐2‐hydroxymethylprop‐1‐ene‐3‐ol. Treatment of the latter diester with methanolic hydrogen chloride produces methyl 4,4‐dimethoxy‐3‐(methoxymethyl) butyrate from the dihydroxynitrile moiety.

Diol lipids

Neutral fats of animal, plant and microbial origin contain minor amounts of two new types of lipids: long-chain diesters of dihydric alcohols and 1-alkenyl ethers of their monoesters. These lipids are not usually separated from triglycerides by column or thin-layer chromatography, but may be detected by high-temperature gasliquid chromatography. Among the dihydric alcohols entering into the composition of neutral lipids from corn seeds, soil yeasts (Lipomyces sp.) and rat liver, ethylene glycol, propane-1,2-diol, propane-1,3-diol, butane-1,3-diol and butane-1,4-diol were identified. The new class of lipids, for which the general term diol lipids is suggested, is apparently widespread in nature.