Stereochemistry of α-parinaric acid fromImpatiens edgeworthii seed oil

alpha-Parinaric acid is a major constituent fatty acid (48%) fromImpatiens edgeworthii Hook F. seed oil. Partial hydrazine reduction of the tetraene gave products which permit defining the stereochemistry of alpha-parinaric acid. Its structure iscis-9,trans-11,trans-13,cis-15-octadecatetraenoic acid. The tetraene readily reacts with maleic anhydride to give the Diels-Alder product with notrans-unsaturation. The formation of this adduct is contrary to previous reports.

Keto fatty acids formCuspidaria pterocarpa seed oil

The seed oil ofCuspidaria pterocarpa contains three keto fatty acids with unusually long carbon chains: 15-oxo-cis-18-tetracosenoic (5.4%), 17-oxo-cis-20-hexacosenoic (13.4%), and 19-oxo-cis-22-octacosenoic (3.3%) acids. These acids were isolated by countercurrent distribution of the corresponding methyl esters. Their structures were established by oxidative degradation, by reduction to known compounds, and by nuclear magnetic resonance and infrared spectra.

Glycolipids ofBriza spicata seed

The seeds ofBriza spicata contain 20% of lipid that is semisolid and quite unusual in character. This lipid contains 49% digalactosylglycerides, 29% monogalactosylglycerides, and consequently little, if any, conventional triglycerides. The predominant fatty acids present are palmitic, oleic, and linoleic. Partial resolution of the galactosylglycerides on the basis of fatty acid composition was achieved by countercurrent distribution.