Helichrysum Seed Oil. II. Structure and Chemistry of a New Enynolic Acid¹

Absolute configurations of 13-hydroxydocosanoic and 17-hydroxyoctadecanoic acids

“…Methyl 9-D-hydroxyoctadecanoate was obtained from hydrogenated oil of Dimorphotheca aurantiaca (9,10). The specific rotation in methanol solution is shown in Table I and is very similar to that reported previously (5).…”

“…The oil (60 g) was hydrogenated in glacial acetic acid using 10% palladium on charcoal as catalyst (10). Methyl esters (56 g) were obtained by refluxing the hydrogenated oil with 4 % methanolic hydrogen chloride.…”

Gas chromatography‐mass spectrometry of methyl esters of unsaturated oxygenated fatty acids

“…Advantages from analysis of the silylated unsaturated oxygenated esters over analysis of their saturated analogs are: (a) unsaturation, in addition to the oxygen function, is located; (b) side reactions that occur during catalytic hydrogenation (7)(8)(9) and complicate GC analysis are avoided; (c) rearrangements during MS are minimized; and (d) molecular ions (M) are usually present in significant amounts.…”

Lipoxygenase fromZea mays: 9‐d‐hydroperoxy‐trans‐10,cis‐12‐octadecadienoic acid from linoleic acid

“…The products, methyl hydroxystearates, were isolated by column chromatography between fractions 57 and 81. Other products (Table II) were due to hydrogenolysis commonly observed in the reduction of activated hydroxyls (15).…”

“…15 decoupled it from Hto at 5 5.63 and caused the Hlo doublet-split-doublet to collapse to a simple doublet with a splitting of 15.4 Hz, which result is typical of a trans proton coupling accross a double bond. Thus the double bond adjacent to the hydroxyl carbon is trans.…”