CRYSTAL-STRUCTURE OF THE COPPER(II) CHLORIDE COMPLEX OF 3,5-DIIODO-L-TYROSINE

The crystal structure of the copper(II) chloride complex of the thyroid hormone precursor, 3,5-diiodo-L-tyrosine, (C9H9I2NO3.CuCl) was determined by the X-ray diffraction method. The space group is P2(1)2(1)2(1), with cell dimensions a = 8.405(2), b = 20.694(3) and c = 7.532(3) angstrom. The structure was refined to R = 0.064 for 1374 reflections (I > 3sigma(I)). The Cu(II) ion is six-coordinated by interaction with one amino nitrogen, two carboxyl oxygens and one chlorine atom in a square plane, and the phenol iodine and oxygen atoms in axial positions. Three-dimensional arrangement of the molecules are stabilized by two hydrogen bonds of O-H(phenol) - - 0(carboxyl), and N-H(amino) .. O(carboxyl).