title: Structure of the radiation protection agent S-3-(3-methylaminopropylamino)propylphosphorothioic acid (WR 151,327).
abstract: C7H19N2O3PS.3H2O, Mr = 296.3, triclinic, P1, a = 6.859 (2), b = 7.077 (2), c = 16.326 (5) A, alpha = 96.64 (2), beta = 100.66 (2), gamma = 105.82 (2) degrees, V = 737.7 A3, Z = 2, D chi = 1.337 g cm-3, Mo K alpha, lambda = 0.71073 A, mu = 3.33 cm-1, F(000) = 320, room temperature, final R = 8.4% for 1614 reflections with /F0/ greater than 3 sigma. The overall conformation of the molecule is linear with a bend at the terminal N atom. The molecule is a double zwitterion with the two phosphate hydrogens residing on the two N atoms, and the three P-O bonds are of equal length at approximately 1.51 A. The S-P bond is unusually long at 2.13 A. Each H atom on each N atom and in each water molecule participates in hydrogen bonding. Within the crystalline lattice the molecule forms head-to-tail dimers.
authors.affiliation: Department of Pharmacology, Walter Reed Army Institute of Research, Washington, DC 20307-5100.
authors.forename: J M
authors.initials: JM
authors.lastname: Karle
authors.forename: I L
authors.initials: IL
authors.lastname: Karle
mesh_terms: D003461:Crystallography; D008968:Molecular Conformation; D009946:Organothiophosphorus Compounds; D011837:Radiation-Protective Agents
chemical_list: D009946:Organothiophosphorus Compounds; D011837:Radiation-Protective Agents; C048392:WR 151327