title: Structural characterization of anhydrous naloxone- and naltrexone hydrochloride by high resolution laboratory X-ray powder diffraction and thermal analysis.
abstract: The crystal structures of the analgesic compounds anhydrous naloxone and naltrexone hydrochloride were determined ab initio from high resolution laboratory X-ray powder diffraction data. Both compounds crystallize in the orthorhombic space group P2(1)2(1)2(1) with lattice parameters of a = 14.6588(10) A, b = 17.4363(9) A, c = 7.96200(22) A, and V = 2035.06(23) A(3) for naloxone hydrochloride and a = 15.4560(5) A, b = 14.9809(4) A, c = 7.84121(18) A, and V = 1815.58(11) A(3) for naltrexone hydrochloride. The crystal structure of anhydrous naloxone hydrochloride forms one-dimensional chains through hydrogen bonds. In the crystal structure of anhydrous naltrexone hydrochloride, two-dimensional sheets are formed by hydrogen bonds. The dehydration processes of naloxone hydrochloride dehydrate and naltrexone hydrochloride tetrahydrate was analyzed by DTA, DSC, TG, and MG.
authors.affiliation: Max-Planck Institute for Solid State Research, Heisenbergstrasse 1, Stuttgart, Germany.
authors.forename: Kunihisa
authors.initials: K
authors.lastname: Sugimoto
authors.forename: Robert E
authors.initials: RE
authors.lastname: Dinnebier
authors.forename: Marek
authors.initials: M
authors.lastname: Zakrzewski
mesh_terms: D002152:Calorimetry, Differential Scanning; D003460:Crystallization; D018360:Crystallography, X-Ray; D003890:Desiccation; D004055:Differential Thermal Analysis; D006860:Hydrogen Bonding; D008958:Models, Molecular; D015394:Molecular Structure; D009270:Naloxone / Q000737:chemistry*; D009271:Naltrexone / Q000737:chemistry*; D009292:Narcotic Antagonists / Q000737:chemistry*; D033362:Powder Diffraction; D013678:Technology, Pharmaceutical / Q000379:methods*; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D009292:Narcotic Antagonists; D014867:Water; D009270:Naloxone; D009271:Naltrexone