Produkte des reduktiven Abbaus von α‐(Acyloxy)plasmalogenen aus Rindergewebe‐Lipiden mit LiAlH₄

Abstract

Products of Reductive Degradation of a-(Acy1oxy)plasmalogens from Bovine Tissue Lipids If bovine tissue lipids are treated with LiA1H4, two types of ether-en01 acetate structure was synthesized and treated with unexpected products are detectable: 1-Acetylglycerols (homo-LiA1H4. Corresponding derivatives of 1-acylglycerols 2 as well logs of compound 2) and a-hydroxylated glycerol acetals as a-hydroxylated glycerol acetals 7 and 8 were produced, thus (homologs of compounds 7 and 8). This fact was assumed to confirming the existence of a-(acy1oxy)plasmalogens 1 in tisindicate the presence of a-(acy1oxy)plasmalogens 1, an up to sue of natural origin. They are detectable by GC and GC/MS now unknown class of mammalian tissue lipids. To confirm after conversion of free hydroxy groups with diazomethane/ this assumption, the model compound 6 possessing an enol silica gel into the corresponding methyl ether derivatives.Kurzlich zeigten wir, daD maskierte, d. h. gebundene langkettige a-Hydroxyaldehyde nach Aufarbeitung von Rindergewebe-Lipiden als Dithiolanderivate nachweisbar sind I,*). Wir kamen zu dem SchluD, daD diese a-Hydroxyaldehyde aus a-(Acy1oxy)plasmalogenen 1 freigesetzt werden. In dieser Arbeit berichten wir uber weitere Befunde, die fur das Vorkommen von a-(Acy1oxy)plasmalogenen 1 in Rinderorgan-Lipiden sprechen. Unterzieht man Rinderleber-Lipid einer reduktiven Aufarbeitung mit LiA1H43.4), trennt entstandene Fettalkohole dunnschichtchromatographisch ab, setzt die Restprobe mit CH,N2/Kieselge15) zu Methoxyderivaten um und fraktioniert die Produkte erneut durch DC, so findet man mit GC/MS in Proben einer Fraktion (chromatographische Daten siehe exp. Teil) 1 -Glycerolfettsaureester-Derivate 24). Detektierbar sind ausschlieDlich homologe Verbindungen der Struktur 2 mit vornehm- OCH3

Solvent-free Lipase-Catalyzed Preparation of Long-Chain Alkyl Phenylpropanoates and Phenylpropyl Alkanoates

“…The resulting mixture of methyl esters, unreacted alkanols or 3-phenylpropanols, and alkyl cinnamates or 3-phenylpropyl alkanoates was analyzed by GC. The phenolic hydroxy group of 2-hydroxycinnamic acid derivatives was methylated to the 2-methoxy compounds by treatment with an ethereal solution of diazomethane in the presence of catalytic amounts of silica gel (45) to avoid coumarin formation during hightemperature GC. A Hewlett-Packard (Bo ¨blingen, Germany) HP-5890 series II gas chromatograph equipped with a flame ionization detector was used.…”

Highly Efficient Preparation of Lipophilic Hydroxycinnamates by Solvent-free Lipase-Catalyzed Transesterification

“…The resulting mixtures of hydroxylated cinnamic acid methyl esters, unreacted alkanols, and 3-phenylpropanols as well as medium-and long-chain alkyl hydroxycinnamates and 3-phenylpropyl alkanoates were analyzed by GC. The phenolic hydroxy group of 2-hydroxycinnamic acid derivatives was methylated to the 2-methoxy compounds by treatment with an ethereal solution of diazomethane in the presence of catalytic amounts of silica gel (33) to avoid coumarin formation during high-temperature GC. Similarly, phenolic hydroxy groups of hydrocaffeic and caffeic acid derivatives were (partially) methylated to improve FID response.…”

Formation of N- and O-methyl derivatives of lipids containing amino, amide or hydroxy groups by the pyrolytic reaction with trimethylsulfonium hydroxide

“…Methoxy fatty acid methyl esters were obtained from the corresponding hydroxy fatty acid methyl esters by the reaction with diazomethane in the presence of silica gel [29,30].…”