Natural Origin of Optically Active Substances and Optical Resolution by Symmetric Agents

Abstract

THE communication by R. C. Ferreira¹ stresses the implications of his findings (and those of H. M. Powell²) on the origin of ‘molecular dissymmetry’ in living matter through nucleation of a saturated solution of an externally compensated compound by a crystal containing an excess of one enantiomer. Possibly certain earlier work bearing upon the same fundamental principle runs some danger of being overlooked. It was observed more than a hundred years ago³ that a solution of externally compensated ammonium hydrogen malate upon evaporation deposited crystals containing about three parts of the (−)-salt to one part of the (+)-salt, showing that a partial spontaneous resolution had taken place.