Biomaterial Database

Redetermination of the crystal and molecular structure of the antimalarial chloroquine bis(dihydrogenphosphate) dihydrate. 1988

J M Karle, and I L Karle

Department of Pharmacology, Walter Reed Army Institute of Research, Washington, DC 20307-5100.

N4-(7-Chloro-4-quinolinyl)-N',N'-diethyl-1,4-pentanediamine bis(dihydrogenphosphate) dihydrate, C18H28ClN2+(3).2H2PO-4-2H2O, Mr = 551.8, monoclinic, P2(1)/c, a = 9.830 (2), b = 16.879 (3), c = 15.783 (4) A, beta = 105.51 (2) degrees, V = 2523.2 A3, Z = 4, Dx = 1.452 g cm-3, Mo K alpha, lambda = 0.71073 A, mu = 2.78 cm-1, F(000) = 1168, room temperature, final R = 5.5% for 2431 reflections with [F0] greater than 3 sigma. The chloroquine molecule is a dication with a hydrogen atom from each of the phosphate moieties residing on the quinoline and the terminal chain nitrogen atoms. Neighboring phosphate chains are bridged by chloroquine molecules via hydrogen bonding. Each hydrogen atom on each nitrogen atom, on each phosphate oxygen atom, and in each water molecule participates in hydrogen bonding. The helical manner in which the side chains of the chloroquine molecules wrap around phosphate chains and the stacking interval of the quinoline rings between the phosphate groups may be indicative of the interaction of chloroquine molecules with cellular constituents important to antimalarial action.

UI	MeSH Term	Description	Entries
D002738	Chloroquine	The prototypical antimalarial agent with a mechanism that is not well understood. It has also been used to treat rheumatoid arthritis, systemic lupus erythematosus, and in the systemic therapy of amebic liver abscesses.	Aralen,Arechine,Arequin,Chingamin,Chlorochin,Chloroquine Sulfate,Chloroquine Sulphate,Khingamin,Nivaquine,Sulfate, Chloroquine,Sulphate, Chloroquine
D006860	Hydrogen Bonding	A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.	Hydrogen Bonds,Bond, Hydrogen,Hydrogen Bond
D000962	Antimalarials	Agents used in the treatment of malaria. They are usually classified on the basis of their action against plasmodia at different stages in their life cycle in the human. (From AMA, Drug Evaluations Annual, 1992, p1585)	Anti-Malarial,Antimalarial,Antimalarial Agent,Antimalarial Drug,Anti-Malarials,Antimalarial Agents,Antimalarial Drugs,Agent, Antimalarial,Agents, Antimalarial,Anti Malarial,Anti Malarials,Drug, Antimalarial,Drugs, Antimalarial
D014961	X-Ray Diffraction	The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Xray Diffraction,Diffraction, X-Ray,Diffraction, Xray,Diffractions, X-Ray,Diffractions, Xray,X Ray Diffraction,X-Ray Diffractions,Xray Diffractions
D015394	Molecular Structure	The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.	Structure, Molecular,Molecular Structures,Structures, Molecular