THE HIGHLY UNSATURATED ACIDS IN SARDINE OIL. XL THE CONSTITUTION OF NISINIC ACID C24H36O2 IN SARDINE OIL

Abstract Nisinic acid C24H36O2 has been separated from sardine oil, and its amyl ester subjected to ozonolysis. Among the products of ozonolysis were found: propyl aldehyde, propionic acid, asetaldehyde, acetic acid, carbon dioxide, succinic acid and amyl hydrogen succinate. Of these compounds propyl aldehyde and propionic acid are derived from the group CH3·CH2·CH=, whilst acetaldehyde and acetic acid together with carbon dioxide are attributable to the secondary decomposition of malonic acid and the corresponding aldehyde which are derived from the group =CH·CH2·CH=. The yield of carbon dioxide indicated the presence of more than two of the group =CH·CH2·CH=. Succinic acid and amyl hydrogen succinate are derived from the groups =CH·(CH2)2·CH= and =CH·(CH2)2·COOC5H11 respectively. Accordingly, nisinic acid was found to be composed of the following groups: CH3·CH2·CH=, CH·CH2·CH=(three), =CH·(CH2)2·CH= (two), and =CH·(CH2)2·CH= were not determined in these experiments. If, however, it is assumed that three of the ethylenic linkings in nisinac acid lie at 4:5-, 8:9- and 12:13-positions as is the case with previously studied moroctic, eicosatetraenoic and clutanodonic acids,the constipution of nisinic acid is expressed by the following formula: CH3·CH2·CH=CH·CH2·CH=CH·CH2·CH=CH·CH2·CH=CH·(CH2)2·CH=CH·(CH2)2·CH=CH·(CH2)2·COOH