9%; the probable error is 6%. Assuming that a monomolecular layer of methyl red is adsorbed, the area covered by a methyl red molecule is ca. 160 sq. A. This value is in reasonable agreement with the projected area (125 sq. A.) of the flat-lying molecule using Pauling's values (9) for the necessary covalent and van der Waals' radii.The above results constitute a calibration of the methyl red adsorption method. The accessible surface area of alumina-silica and silica gel can be determined with a probable error of 6% simply by measuring methyl red adsorption as described and multiplying the resulting quantity by the factor, 960 sq. meters per mmole.Fine-Pore Samples. Samples of magnesia-silica (together with one alumina and two silica gel samples) adsorbed considerably less methyl red per unit area than the 1.04 Mmoles

No abstract

Fatty acids, recently reported as constituents of certain fish lipids, were identified to be derivatives of furan (furanoid fish fatty acids). 12,15-Epoxy-13,14-dimethyleicosa-12,14-dienoic acid is predominant among the furan acids and is associated with bis-homologs in regard to chain length. Monomethyl acids, such as 12,15-epoxy-13-methyleicosa-12,14-dienoic, are present in appreciable amounts. The structures were concluded from oxidative degradations, from mass spectrometry of methyl esters of the novel acids and fatty acids derived from them by opening the ring, and from nuclear magnetic resonance, infrared, and Raman spectra. The results from chemical procedures and from spectrometric methods were in agreement with those obtained with authentic methyl 9,12-epoxyoctadeca-9,11-dienoate. The number of substituents at the furan ring greatly influences hydrogenation, hydrogenolysis, and hydrolysis reactions of the ring.

An efficient procedure for preparing phytenic acid methyl ester, free of isomers, from phytol is reported. Phytyl phytenate and other isoprenoid wax esters were synthesized. Gas liquid chromatography of these wax esters and other compounds related to phytol and phytenic acid is described. The alkyl constituents of isoprenoid wax esters can be analyzed after alkaline methanolysis and the acyl constituents after acidic methanolysis. The applicability of these methods to natural mixtures was demonstrated with wax esters from mosses which contained both types of isoprenoids and with wax esters from healthy and frost damaged grass which contained phytol, but not phytenic acid.