Preferential Crystallisation of one Stereoisomer from Solutions of Atropine Sulphate in Ethanol

Abstract

Summary Atropine and l-hyoscyamine sulphates crystallise from ethanol solution as alcoholates. The solubility of l-hyoscyamine alcoholate is considerably lower than that of the atropine compound, which may account for the “spontaneous resolution” of the latter. The direction of optical rotation of crystals from deliberately seeded atropine sulphate solutions follows that of the seeds.