Difference in odour of d-, l- and dl-derivatives of amino- and bisamino-methylenecamphors

Abstract

It is well known that optically active isomers, despite the fact that they are identical in structure, differ from one another in those physical properties which are of the directional (vectorial) nature, such as, for example, direction of rotation of the plane of polarized light, unsymmetrical distribution of the hemihedral facets in their crystal forms, etc. The magnitude of these vectorial properties is, however, identical for the enantiomorphous forms. The optically active forms differ also in other respects, namely, in their action on micro-organisms, enzymes and in their physiological behaviour towards higher organisms. In 1886 Piutti1 observed that d-asparagine had a sweet taste, whereas the naturally occurring l-asparagine was insipid. Cushny2 found that l-hyoscyamine was twice as powerful in paralysing the vagus as the racemic form, atropine, while the d-form was twenty times weaker in this action. One of the most striking examples of different physiological activity recently observed is vitamin C or ascorbic acid3: the dextro-rotatory acid is active, the dextro-rotatory form being physiologically inactive.