MALONIC ACID (methane-dicarbonic acid) — the necessary predecessor of fatty acids at their biosynthesis as de novo, and during the lengthening of their carbon chain. M to. it is used at synthesis of barbiturates, in particular veronal (barbital). In exchange reactions takes part in a type of salts — malonates. Malonate is the known competitive inhibitor of enzyme succinatedehydrogenases (see) in a cycle Tricarboxylic to - t (see. Tricarboxylic acids cycle ).
M to. represents crystal white matter with t°pl 135,6 °; restrictedly a rastvorima in water. M to. has all properties carboxylic acids (see), but of it high reactivity of hydrogen atoms of a methylene link is characteristic. Thanks to this M. to. easily enters substitution reactions, condensation, halogenation and it is widely applied in organic synthesis (especially in the form of malonic ester); COOH groups M. to. are easily chipped off during the heating.
In the nature in a stand-at-ease of M. to. meets only in plants.
Bibliography: Lenindzher A. Biochemistry, the lane with English. M, 1976; Nesmeyanov A. N. and Nesmeyanova. A. Beginnings of organic chemistry, book 1, page 182, etc., M., 1974.
N. V. Prokazova.