Constitution of the surface lipid from the leaves of Brassica oleracea (var. capitata ( Winnigstadt )) - II. Esters, free primary alcohols and free acids

Abstract

The constitution of the free primary alcohols and the free acids has been determined by comparing their properties with those of reference compounds on reversed-phase partition film chromatograms. The compositions of the alcoholic and acidic fractions derived from the esters by hydrolysis have been determined in the same way. Usually, at least one member of each group has been isolated, and in each instance the melting point shows that the compounds belong to the normal series. In all, seven free alcohols, five free acids, six ester-alcohols and five ester-acids have been identified. Only even-numbered carbon chains are present: the acids range from n -dodecanoic to n -tetracosanoic acid and the alcohols range from n -dodecanol to n -octacosanol. In each group at least two members of the series are missing. The missing members might be present, and so too might members of the odd-numbered carbon series but, if so, the amounts could not exceed 1 % each.