ASA (2-stearoyldiacetin) and APA (2-palmitoyldiacetin) occur in metastable subalpha and alpha forms and stable beta prime-like forms (alpha heing questionable for the palmitic compound). Mixtures of the symmetricaland unsymmetrical isomers in the binary systems ASA-SAA and APA-PAA show greatly increased alpha stability over that of the pure compounds. Melting points of mixtures in the alpha form lie in a straight line joining those ...