THE SOLUTION AND SOLID-STATE STRUCTURE OF L-CARNITINE L-TARTRATE

L-Carnitine forms a salt-like 2:1 adduct with L-tartaric acid which cr ystallizes in the orthorhombic space group P2(1)2(1)2(1) with Z = 4 fo rmula units in the unit cell. The lattice is composed of an L-tartrate dianion and two crystallographically independent L-carnitinium cation s. The two cations show only very minor differences in their conformat ion. Anions and cations are arranged in separate stacks which are link ed via hydrogen bonds. The tartrate anion and the carnitinium cations show standard geometries known from the structures of other salts of t hese ions, like the L-carnitine component of the R,L-carnitinium chlor ide or the dianion in alkali tartrates. The title compound has galenic advantages as an L-carnitine drug because of its non-hygroscopic prop erties. Aqueous solutions have been shown to contain solvated ionic co mponents, i. e. L-tartrate and L-hydrogentartrate anions, L-tartaric a cid (15:70:15) and carnitinium cations. The title compound can therefo re be classified as a genuine L-carnitinium salt of L-tartaric acid.