The crystal structure of rubidium ammonium hydrogen fluorocitrate dihydrate

摘要: The crystal structure of the racemate rubidium ammonium hydrogen fluorocitrate dihydrate, RbNHaH(C6HaO7F).2H20, containing isomer that inhibits enzyme aconitase, has been determined. configurations two isomers in are I R:2R and 1S:2S for 1-fluoro-2-hydroxy-l,2,3-propanetricarboxylic acid. crystals triclinic, space group PT, Z = 2 , with unit-cell dimensions a=8-458 (2), b= 10.910 (3), c=7.516 (2) A,, 0c= 102.80 ° fl= 115.90 7,=80-50 (4). observed calculated densities 1.92 1.925 g c m 3 respectively. was solved from Patterson map refined to an R value 0.072. All atoms, except on a carboxyl anion, were located difference electron-density map. ion forms tridentate chelate ion, fluorine atom being shared by coordination polyhedra. There is disorder ions approximate extent 84 % and, corresponding this, also disordered 84%, presumed pack so each case coordinated ion.