Metallation of Ligands with Biological Activity: Synthesis and X‐Ray Characterization of [UO₂(PN)₂(H₂O)]Cl₂{PN = vitamin B₆ pyridoxine[2‐methyl‐3‐hydroxy‐4, 5‐bis(hydroxymethyl) pyridine]}

Abstract

Chloridrate of pyridoxine (vitamin B 6 ) reacts with UO 2 (NO 3 ) 2 ·6H 2 O in acetonitril containing triethylamine to give the complex salt [UO 2 (PN) 2 (H 2 O)]Cl 2 . The structure of the novel compound was analyzed by single crystal X-ray diffraction affording the centrosymmetric triclinic space group P1. In [UO 2 (PN) 2 -(H 2 O)] 2ϩ two zwitterionic pyridoxine molecules complex the uranium atom in a planar manner with a water molecule achieving the coordination of a semi planar pentagon. The two uranyl oxo ligands set the axis of a distorted pentagonal bipyramide. The ability of vitamin B 6 pyridoxine to react with UO 2 2ϩ allowing the chela-

Chelation of UO22+ by vitamin B6 complex derivatives: Synthesis and characterization of [UO2(β-pyracinide)2(H2O)] and [UO2(Pyr2en)DMSO]Cl2{Pyr2en=N,N′-ethylenebis(pyridoxylideneiminato)}. A useful modeling of assimilation of uranium by living beings

“…The uranium centers in 1 and 2 adopt a seven-coordinate configuration, already observed in [UO 2 (PN) 2 -(H 2 O)]Cl 2 [40]. This leads to more or less distorted pentagonal bipyramidal structures, completed, in case of 1, by one water molecule, and in case of 2 by one DMSO moiety.…”

“…Although the X-ray structure of a number of metal complexes of vitamin B 6 constituents have been described, like the reaction products of the diethyltin(IV) cation with pyridoxine [45], of dimethyltin(IV) with mono and bis-deprotonated pyridoxine [46,47], of copper(II) perchlorate with pyridoxine and 2,2 0 -bipyridine [48], of Cu(NO) 3 with anionic and neutral pyridoxamine [6], of cobalt(II) perchlorate and copper(II) perchlorate with anionic and neutral pyridoxine and 2,2 0 -bipyridine [11] and those of platinum and palladium salts with pyridoxal, pyridoxine and pyridoxamine [5], with exception of our reported complex [UO 2 (PN) 2 (H 2 O)]Cl 2 [40], up to date no other references have been made to the complexation of uranium by any vitamin B 6 constituent. The synthesis of the title complexes and their structure elucidation, as far we are concerned, represent a further qualitative contribution in the researches on possible models of interaction of radioactive and heavy elements with human beings.…”

Pyridoxinium trichloroacetate

“…For related literature on hydrogen-bond motifs see Etter et al (1990) and for values of bond lengths and angles see Allen et al (1987). For related structures see Longo et al (1982), Bacon & Plant (1980), Longo & Richardson, (1980), Franklin & Richardson (1980), Dey et al (2003), Culbertson et al (2003), Bonfada et al (2005) and Anitha et al (2006). For other related literature, see: Leklem (1990); Sabirov et al (1993); Trakatellis et al (1992).…”

Pyridoxinium picrate

“…The crystal structures of pyridoxine (Longo et al, 1982), pyridoxinium chloride (Bacon & Plant, 1980), pyridoxamine monohydrochloride (Longo & Richardson, 1980), copper complexes of neutral pyridoxamine (Franklin & Richardson, 1980), cis-oxalatobis(pyridoxine)palladium(II) (Dey et al, 2003), 6-dimethylaminopyridoxine-4 -(tert-butyldimethylsilyl ether) (Culbertson et al, 2003) and aquabis(2-methyl-4,5bis(hydroxymethyl)pyridinium-3-oxalato)dioxouranium dichloride (Bonfada et al, 2005) are already known. In the present work, the crystal structure of pyridoxinium picrate, (I), is reported.…”