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1.
Rev Med Suisse ; 1(22): 1511-4, 2005 Jun 01.
Artigo em Francês | MEDLINE | ID: mdl-16025891

RESUMO

The diabetic pathway project is based on the objective of bettering the care of diabetic patients, through a new organisation of the care which should be more based on collaboration, on the sharing of information and on the coordination of activities. This project concern 6000 patients. The diabetic pathway is organised into three groups of intervention. The group called "first intention" (patient, physician and pharmacist), the multidisciplinary group (team of specialized professionals in diabetes care) and the group of independent professionals. The patients care is based on common procedures and guidelines. The physician remains the agent of the patient.


Assuntos
Diabetes Mellitus/terapia , Gerenciamento Clínico , Equipe de Assistência ao Paciente , Humanos , Papel Profissional , Suíça
2.
J Am Chem Soc ; 123(37): 9144-52, 2001 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-11552823

RESUMO

Bis(NBH(3)), bis(NBF(3)), and NBF(3)/NBH(3) adducts 1-3 were prepared from 1,3-dimethyl-1,3-diazolidine and characterized by the (1)H, (13)C, (11)B, (19)F, 2D (1)H(-13)C HETCOR and NOESY NMR spectra. The structures and conformations of the adducts were established by the variable-temperature (1)H NMR spectra, the X-ray diffraction method (adduct 2A), and density functional calculations at different theoretical levels. The experimental and theoretical data have revealed that bis adducts 1-3 prefer trans orientations of the borane groups (1A, 2A, 3A) in solution, the solid state, and the gas phase. The studies have shown that the energetic preference of trans adducts with respect to cis compounds, decreasing as 2A (2.9 kcal/mol) > 3A (2.7 kcal/mol) > 1A (1.4 kcal/mol), is dictated by spatially repulsive interactions between the CH(3), BH(3), and BF(3) groups. The results of DFT calculations agree well with an experimental trans/cis isomeric ratio of 9:1 determined in solutions of adduct 1. The calculated geometry and energy, as well as the topological analysis of electronic densities, show that trans adducts 1-3 should exist in gas phase as twist conformations T-2 stabilized by the intramolecular C-H(delta+)...(-delta)H-B or C-H(delta+)...(-delta)F-B interactions. These interactions are characterized as closed-shell. The energy of one proton-hydride and proton-fluoride intramolecular contact, estimated as 1.9 (1A-T-2) and 0.7 (2A-T-2) kcal/mol, respectively, classifies the "elongated" intramolecular interactions CH(delta+)...(-delta)HB and CH(delta+)...(-delta)FB as weak ones. It has been established that, on going from gas phase to a condensed phase (solution and solid), the twist-conformations T-2 transform to conformations T-1, probably by intermolecular dipole-dipole interactions. The data presented in this work show that despite a weakness of the "elongated" proton-hydride and proton-fluoride interactions, they can play a significant role in the stabilization of conformational molecular states, especially when cooperativity is in action.

3.
Inorg Chem ; 40(14): 3570-5, 2001 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-11421707

RESUMO

The reaction of [N(2)H(5)](+)(2)[SO(4)](2-) with barium 5,5'-azotetrazolate gave new high-energy-density materials (HEDM) based on the 5,5'-azotetrazolate dianion. The dihydrazinium salt of [N(4)C-N=N-CN(4)](2-) 1, its dihydrate 2, and its dihydrazinate 3 were prepared in high yield. Synthesis in water afforded yellow needles of [N(2)H(5)](2)(+)[N(4)C-N=N-CN(4)](2-).2H(2)O (2): monoclinic, P2/c, a = 8.958(2) A, b = 3.6596(7) A, c = 16.200(3) A, beta = 96.834(3) degrees, V = 527.3(2) A(3), Z = 2; synthesis in anhydrous hydrazine gave yellow [N(2)H(5)](2)(+)[N(4)C-N=N-CN(4)](2-).2N(2)H(4) (3): triclinic, P1, a = 4.6208(6) A, b = 8.585(1) A, c = 9.271(1) A, alpha = 108.486(2) degrees, beta = 95.290(2) degrees, gamma = 102.991(2) degrees, V = 334.51(8) A(3), Z = 1. The compounds were characterized by elemental analysis and vibrational (IR, Raman) and multinuclear NMR spectroscopy ((1)H, (13)C, (14)N, (15)N). The new compounds represent new high-nitrogen HEDMs with one of the highest nitrogen contents reported to date ([N(2)H(5)](+)(2)[N(4)C-N=N-CN(4)](2-) 85.2%; [N(2)H(5)](+)(2)[N(4)C-N=N-CN(4)](2-).2H(2)O 73.3%; [N(2)H(5)](+)(2)[N(4)C-N=N-CN(4)](2-).2N(2)H(4) 85.7%). The standard heat of formation of the solvate-free compound 1 was computed at the MP2(FULL)/6-311+G(d,p) level of theory to be DeltaH degrees (f) = 264 kcal mol(-1), which translates to 1147 kcal kg(-1) and is one of the highest ever reported. The compounds are stable at room temperature, almost insensitive to friction and impact, but detonate violently when the explosion is initiated, e.g., by rapid heating over the decomposition temperature or by using an initiator.

4.
Inorg Chem ; 40(6): 1334-40, 2001 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-11300838

RESUMO

The first crystal structures of the highly energetic tetraazidoborate anion and boron triazide adducts with quinoline and pyrazine as well as of tetramethylpiperidinium azide have been determined. Synthesis procedures and thorough characterization by spectroscopic methods of these hazardous materials are given. Quantum chemical calculations were carried out for B(N(3))(4)(-), B(N(3))(3), C(5)H(5)N.B(N(3))(3), (N(3))(3)B.NC(4)H(4)N.B(N(3))(3), and the hypothetical C(3)H(3)N(3).[B(N(3))(3)](3) at HF, MP2, and B3-LYP levels of theory. The structure of tetraazidoborate was optimized to S(4) symmetry and confirmed the results obtained from the X-ray diffraction analysis. The dissociation enthalpies for the pyridine (model for quinoline) as well as for the pyrazine adduct were calculated. For pyridine-boron triazide a value of 10.0 kcal mol(-1) (for pyrazine-bis(boron triazide) an average of 2.35 kcal mol(-1) per BN unit) was obtained.

5.
Chemistry ; 6(19): 3531-9, 2000 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-11072818

RESUMO

From the reaction of trimethylsilyl ylides with AsCl3 the dichloroarsanyl ylides 2b and 5b are obtained. As shown by X-ray structure determination, their AsCl2 groups deviate systematically from the symmetric orientation. This conformation enables an effective charge transfer from the ylide moiety to one of the As-Cl bonds, which as a consequence is up to 15 pm longer than the other. At the same time the length of the As-C bonds in 2b and 5b indicates a partial double bond. The effects observed here are of the same type as those observed for the corresponding dichlorophosphanyl ylides; they are, however, more pronounced. The 1:1 condensation of the bis(trimethylsilyl) ylide 3 and AsCl3 yields the oligomers (Ph3PCAsCl)2,3,4. The dimer 7b has a diarsetane structure. HCl adds readily to one of its As-C bonds without opening it. The trimer and the tetramer are ionic. The cation of the trimer forms a six-membered ring with a delocalized arsenium/phosphonium charge, the cation of the tetramer forms a barrelane cage with a phosphonio substituent, and the anion is AsCl4- in both cases (10, 13). An arsa-phosphocyanine cation as in 10 is also part of the diphosphonio isoarsindolide tetrachloroarsenate(III) 12. The structures of 7b.HCl, 10, and 13 reflect again an ylide to As-Cl charge transfer. The As-Cl bonds of 13 are by far the longest ones known for a chloroarsine (average 249 pm).

8.
Angew Chem Int Ed Engl ; 39(1): 222-224, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10649382

RESUMO

Highly stable multinuclear metal complexes with planar [{Me(3)SiNC(H)N}(2)CH](-) ligands are obtained from MN(SiMe(3))(2) (M=Na, Tl) and 1,3,5-triazine (structure for Tl shown in the picture). These complexes display unusual structural features such as a pseudo-C(3) symmetry (Na complex).

9.
Inorg Chem ; 39(21): 4721-4, 2000 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-11196945

RESUMO

The magnesiation of tri(tert-butyl)silylphosphane in THF yields tetrameric (tetrahydrofuran-O)magnesium tri(tert-butyl)silylphosphandiide 1. The central moiety is a slightly distorted Mg4P4 cube with tetracoordinate magnesium and phosphorus atoms. The reaction of dibutylmagnesium with H2PSitBu3 in toluene gives tetramagnesium tetrakis[mu-tri(tert-butyl)silylphosphanide] bis[mu 4-tri(tert-butyl)silylphosphandiide] 2. The central fragment is a Mg4P2 octahedron with the phosphorus atoms in a trans position. The Mg...Mg edges are bridged by the phosphanide substituents. Crystallographic data of 1: C68H148Mg4O5P4Si4, monoclinic, P2(1)/c, a = 13.454(1) A, b = 26.123(1) A, c = 24.539(2) A, beta = 96.53(1) degrees, Z = 4; crystallographic data of 2: C72H166Mg4P6Si6, monoclinic, P2(1)/n, a = 13.951(1) A, b = 14.269(1) A, c = 24.209(2) A, beta = 102.415(1) degrees, Z = 2.

10.
Angew Chem Int Ed Engl ; 38(21): 3225-3228, 1999 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-10556910

RESUMO

Self-assembly of chiral, half-sandwich complexes results in the formation of triangular metallomacrocycles under complete stereocontrol and in quantitative yields. The assembly-disassembly process can be triggered by the addition of acid or base (see scheme).

11.
Angew Chem Int Ed Engl ; 38(8): 1103-5, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-25138509

RESUMO

Dark violet hexastannane (tBu3 Si)6 Sn6 displays a new framework motif for molecular tin compounds, in which six Sn atoms are located at the corners of a trigonal prism. The compound can be synthesized according to Equation (a). R*=SitBu3 .

12.
13.
Inorg Chem ; 36(6): 1070-1075, 1997 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-11669670

RESUMO

The 1:1 reactions of [((i)()Pr(2)N)BP(H)B(N(i)()Pr(2))PLi.DME] (1) and [(tmp)BP(H)B(tmp)PLi.DME] (2; tmp = 2,2,6,6-tetramethylpiperidino) with organylhalostannanes have been examined, and stannyl-substituted diphosphadiboretanes, (R(2)N)BP(H)B(NR(2))PSn(Cl)R'(2) (R(2)N = (i)()Pr(2)N, tmp; R' = Me, (t)()Bu) have been isolated and characterized. Dehydrohalogenation of these compounds with (t)()BuLi produced bicyclic cage compounds P(2)(R(2)NB)(2)SnR'(2) (R(2)N = (i)()Pr(2)N (9), tmp (8); R' = (t)()Bu) or an oligomer [-P(R(2)NB)(2)PSn(R'(2))-] (R(2)N = tmp; R' = Me). The 2:1 reactions of R'(2)SnCl(2) with 1 and 2 have been studied, and with a small R' group (Me) a disubstitution product, [HP(tmpB)(2)P](2)SnMe(2) (11), is obtained. With a larger R' group ((t)()Bu), cage products P(2)(tmpB)(2)Sn(t)()Bu(2) and P(2)((i)()Pr(2)NB)(2)Sn(t)()Bu(2) are isolated. The molecular structures of 8 and 9 have been determined by single crystal X-ray diffraction techniques, and these structures and their spectroscopic features are discussed in relation to other boron-phosphorus cage compounds.

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