Angelo Diaz

Brain copper, iron, magnesium, zinc, calcium, sulfur and phosphorus storage in Wilson's disease.

PROJECT Wilsons disease (WD) is an inherited disorder of copper metabolism characterised by juvenile liver cirrhosis and by neurological symptoms. Copper levels in brain in WD have been reported to be 10 to 15 fold normal values, depending on the different brain regions. Being very few data on copper distribution in central nervous system in WD available, it seemed of interest to study the concentration of copper and of other trace elements (Zn, P, Mg, Ca, Fe and S) in the brain of a patient died for WD. PROCEDURE a 56 year old woman affected by WD was admitted to our hospital with signs of hepatic failure and died few days later. At autopsy, a brain slice extending from the left to the right hemisphere was divided in 28 samples. On each sample Copper, Iron, Magnesium, Phosphorus, Sulphur, Zinc and Calcium were determined by Induced Coupled Plasma Atomic Emission Spectroscopy. RESULTS the mean concentration of copper, ranging from 88 to 158 microg/g of dry tissue in all the brain specimens was higher than literature reference values, while that of the other tested elements was considerably lower. CONCLUSIONS 1) In the brain of WD patient examined the status of trace elements was extensively altered. Further studies are necessary to correlate the concentration of trace elements with pathological lesions and with clinical pictures. 2) The elements considered in our study showed an uneven distribution in different brain areas.

REACTION OF CuX2(X = Cl, Br) WITH 5,5-DIMETHYLMIDAZOLIDINE-2,4-DITHIONE (ss), AND THEIR -2-ONE-4-THIONE (oxs) AND -2-THIONE-4-ONE (sox) ISOLOGUES-CRYSTAL STRUCTURES OF CU(oxs)2Br AND Cu(ss)2Cl

Abstract Copper(I) complexes, obtained by reacting CuX2 (X = Cl, Br) with 5.5-dimethylimidazolidine-2-thione-4-one (sox), and its 2-one-4-thione (oxs) and 2,4-dithione (ss) derivatives, are reported. Infrared spectra show evidence for S-coordination in all the complexes. The crystal structure of Cu(oxs)2Br shows dimeric units, where every copper(I), practically trigonal planar, undergoes a tetrahedral distorsion by long range interactions with one bridging bromine and one bridging sulphur atom of oxs. The crystal structure of Cu(ss)2Cl is formed by a polymeric chain in which every copper has a tetrahedral environment, achieved by two ligands bridged via the two sulphur atoms between two coppers, one ligand bonded only through the 2-thione sulphur, and one chlorine. The distortions of the C=O and C=S groups from the symmetrical positions with respect to the other two bonds of the C(sp2) carbons, verified in the complexes and in the free ligands, are interpreted in terms of the VSEPR model.

Characterization of tricarbonyl-chromium(0), -molybdenum(0) and -tungsten(0) complexes with 2,2-para-cyclophane

Abstract Complexes of the type M(CO) 3 (22cy), where M = Cr, Mo, W and 22cy = 2,2-para-cyclophane were prepared and characterised. The i.r., p.m.r., mass spectrography spectra are discussed. The Mo derivative decomposes in solution giving 22cy, Mo(CO) 6 and Mo, according to a first order mechanism.

NH stretching vibrations of 5,5-dimethylimidazolidines with O,S or Se at C-2 and C-4☆

Abstract The i.r. spectra of the title compounds have been recorded in the region 3500-3150 cm −1 in CH 2 Cl 2 and CH 2 Cl 2 /DMSO solutions. In the region of the free NH stretching vibrations, the spectra show an envelope of bands which have been deconvoluted in order to separate the two ν (NH) contributions. The peak due to ν (NH) of N-3 decreases on increasing the DMSO concentration, thus indicating that this hydrogen is mainly involved in the interaction with DMSO in accordance with its higher acidity. The influence of the exo-chalcogen atoms on these frequencies has been discussed. A good empirical correlation has been found between the ν (NH)s and the charge densities (calculated by CNDO/S) on the hydrogen and nitrogen atoms.

Copper (I) complexes of pentatomic heterocyclic selone donors

SummaryNew complexes of copper(I) with some heterocyclic pentatomic rings, X·CH2·CH2·NR·CSe, where X=CH2, NH, NMe, NEt, S and R=H, Me, Et, were prepared by reacting copper(II) chloride and bromide in MeOH. The stoichiometry of the complexes and the binding mode of the ligands have been discussed comparatively, together with those of the thione parents. It is noteworthy that the selone ligands with R=H (L) yield complexes of the type CuLnY, (n=1,2 or 3; Y=Cl or Br) like the corresponding thione ones. On the contrary, when R=Me or Et, the selonic ligands (L′) give complexes whose stoichiometries, Cu2L′Y2 and Cu3L′2Y3, differ from the thione homologues. The i.r. spectra of the complexes compared with those of the ligands support the coordinative bondvia selenium atom.

HYDANTOIN DERIVATIVES. SYNTHESES AND INFRARED SPECTRA OF 5,5-DIMETHYLIMIDAZOLIDINES HAVING O, S OR SE ATOMS AT C-2 AND C-4

Abstract The syntheses of a complete series of 5,5-dimethylimidazolidines 2,4-disubstituted with chalcogen atoms (O, S and Se) are reported. Their infrared spectra (4000–250 cm−1) are discussed on the basis of the selenation effect and the bands arising from [sbnd]HN[sbnd]CX[sbnd]NH[sbnd]CY[sbnd] (X, Y=O, S, Se) groups are tentatively assigned.

Reactivity of mercury(II) perchlorate towards 5,5-dimethylimidazolidine-2-thione-4-one. Structure of bis(5,5-dimethylimidazolidine-2-thione-4-one)mercury(II) perchlorate triaquo.

Abstract The reaction between Hg(GO4)2 and 5,5-Dimethylimidazolidine-2-thione-4-one (L) has been investigated in water, diethylether and perchloric acid solutions. In water, three different complexes, HgL(ClO4)2·nH2O, HgL′ClO4 and HgL′2 (L′ = deprotonated L) have been obtained; in diethylether HgLn(C104)2 (n = 1, 3–5) was prepared, whereas in perchloric acid solutions, besides the HgL2(CIO4)2 complex, a mercury(I) complex of formula HgL2ClO4 was obtained at high acid concentration. The mercury(I) complex can also be obtained at a lower acid concentration using a L:Hg(ClO4)2 molar ratio higher than 2:1. The crystal structure of bis(5,5-dimethylimidazolidine-2-thione-4-one) mercury(II) perchlorate triaquo shows the existence of the [HgL2]2+ cation, in which the coordination around the mercury atom is almost linear.

1H and 13C NMR study on some substituted azolidine derivatives

Abstract The 1 H and 13 C NMR spectra carried out on R N·CH 2 ·CH 2 ·X·C O (where for R = H, X = NH, NMe, NEt, CH 2 , S, O; for R = Me, X = NMe, CH 2 ; for R = Et, X = NEt) are reported. The comparison of these results with those obtained for the thionic and selonic isologues shows that sulphur and selenium have a greater deshielding effect on the ring than oxygen. The resonance of the carbons not involved in the π system have been correlated with the σ charges calculated by the Del Re method.

Diselenocarbamates with tetrahedral, octahedral or square-pyramidal stereochemistry

Abstract Tetrahedral of Group II B metals and octahedral diselenocarbamates of iron(III), cobalt(III) and chromium(III) were isolated as well as some squarepyramidal Fe(dsc) 2 X (where X = Cl, Br, I) derivatives. The magnetic moment values, infrared and electronic spectra are reported and interpreted to obtain the ligand field parameters and the selenium nephelauxetic effect. The increase of the NC double bond character with coordination is pointed out and discussed in comparison with the corresponding dtc derivatives.

Five-coordinated complexes of cadmium(II) and mercury(II) with tripod-like tetramines

Abstract Some complexes of cadmium(II) and mercury(II) with the tetramines tris(2-aminoethyl)amine, tren, and tris(2-dimethylaminoethyl)amine, Me 6 tren, are described. The anions are Cl − , Br − , I − , SCN − , NO 3 − , ClO 4 − , BPh 4 − . They were characterized by chemical analysis, electric conductivity, and vibrational spectroscopy. According to the nature of metal, amine, and anion a variety of complexes of different stoicheometries has been obtained. The cationic species are of the types [MX(Me 6 tren)] + and [MX(tren)] + (X = Cl, Br, I, ClO 4 , SCN) where the metal ions are five-coordinated. Metallic anionic species are [HgCl 4 ] 2− , [HgBr 4 ] 2− , and the novel ones [Cd 2 I 6 ] 2− , [Hg 2 I 6 ] 2− , and [Hg 2 Br 6 ] 2− , all having tetrahedrally coordinated metal ions. The neutral complexes CdCl 2 (Me 6 tren) and CdBr 2 (Me 6 tren) are five-coordinated, with the amine acting as a tridentate ligand.