PubMed Health⌕ Search

Biomedical subjects

F D Rochon

Publications and source records attributed to F D Rochon.

7 recordsLinked to original sources
PubMed2001

Novel pyrimidine-bridged platinum(II) complexes: multinuclear magnetic resonance spectroscopy and crystal structures of (NR4)2[(PtCl3)2(mu-pyrimidine)] and cis- and trans-[Pt(R2SO)Cl2]2(mu-pyrimidine).

Two new types of pyrimidine-bridged Pt(II) complexes, (NR4)2[(PtCl3)2(mu-pm)] and cis- and trans-[Pt(R2SO)Cl2]2(mu-pm) where pm = pyrimidine, were synthesized and characterized by IR and multinuclear magnetic resonance spectroscopies and by crystallographic methods. Compounds with dimethylsulfoxide, tetramethylenesulfoxide, di-n-propylsulfoxide (DPrSO), di-n-butylsulfoxide (DBuSO), dibenzylsulfoxide (DBzSO), and diphenylsulfoxide were studied. The aqueous reaction of K2PtCl4 with pyrimidine produced the [(PtCl3)2(mu-pm)](2-) ions, which can be precipitated with a NR4(+) salt. The aqueous reaction of K[Pt(R2SO)Cl3] with pyrimidine in a 2:1 ratio produced the dinuclear species trans-[Pt(R2SO)Cl2]2(mu-pm). With DBuSO and DBzSO, the analogous cis isomers were also obtained. The 195Pt NMR resonances of the trans dimeric complexes were observed at higher field (av -3088 ppm) than the cis compounds (av -2948 ppm). The 195Pt coupling constants with the atoms of pyrimidine 3J(195Pt-1H) and 3J(195Pt-13C) are larger in the cis configuration than in the trans analogues. The crystal structures of two ionic complexes, (NR4)2[(PtCl3)2(mu-pm)] (R = Me and n-Bu), and of three mixed-ligands dimers, trans-[Pt(R2SO)Cl2]2(mu-pm) (R2SO = DMSO, DPrSO) and cis-Pt(DBuSO)Cl2]2(mu-pm), were determined.

Carbon Isotopes↗
PubMed2000

Syntheses of new ionic technetium(III) complexes containing four monodentate phosphine ligands. Crystal structures of trans-[Tc(PMe2Ph)4Cl2]PF6, trans-[Tc(PMe3)4Cl2]BPh4, and trans-[Tc(PMe3)4Cl2]PF6.

New ionic technetium complexes of the type trans-[Tc(PR3)4Cl2]+ are synthesized by various methods. The simplest method is the reaction of [TcO4]- with the phosphine in methanol in the presence of a chloride salt. Compounds containing PMe2Ph and PMe3 are synthesized and characterized by crystallographic methods. The complexes containing the less bulky phosphine can be prepared from complexes containing the bulker phosphine. The compounds are paramagnetic, with two unpaired electrons. The complexes studied by X-ray diffraction methods are the trans isomers. [Tc(PMe2Ph)4Cl2]PF6 crystallizes in the monoclinic space group P2(1)/c, with a = 11.511(2) A, b = 26.713(7) A, c = 12.688(3) A, beta = 92.79(1) degrees, Z = 4, and R1 = 0.0574. [Tc(PMe3)4Cl2]BPh4 (II) crystallizes in the orthorhombic space group Pbcn, with a = 18.213(5) A, b = 22.950(5) A, c = 19.428(6) A, Z = 8, and R1 = 0.0691. [Tc(PMe3)4Cl2]PF6 crystallizes in the monoclinic space group P2(1)/c, with a = 18.152(7) A, b = 16.838(9) A, c = 18.090(6) A, beta = 106.63(1) degrees, Z = 8, and R1 = 0.0670. The compounds all have octahedral coordination, but an important tetrahedral deformation of the plane containing the Tc and the four P atoms is observed in each case. In II, the two independent Tc atoms are both located on 2-fold axes.

Crystallography, X-Ray↗
PubMed1999

(2S*,4S*,5R*)-4-methyl-2-[(5S*)-3-methyl-4,5-dihydroisoxazol-5-yl]-5- phenyl-3-(toluene-4-sulfonyl)oxazolidine.

The title compound, C21H24N2O4S, containing 2-isoxazoline and oxazolidine moieties, was studied in order to determine its relative configuration, which could not be determined unambiguously by NMR techniques. The results have shown that the substituents on the three C atoms of the oxazolidine cycle are all on the same side of the ring, while the aromatic group of the toluene-4-sulfonate substituent on the N atom is located on the opposite side. The 2-isoxazoline ring was found to have the 5'S* configuration.

Antineoplastic Agents↗
PubMed1989

Structures of cis-amminedichloro(cyclopentylamine)platinum 0.25-hydrate and potassium trichloro(cyclopentylamine)platinate 0.5-hydrate.

cis-Pt(NH3)(cyclopentylamine)Cl2.1/4H2O, C5H14Cl2N2Pt.0.25H2O, Mr = 372.7, tetragonal, P-4b2, a = 11.456 (4), c = 16.172 (6) A, V = 2122 (1) A3, Z = 8, Dx = 2.333 Mg m-3, lambda(Mo K alpha) = 0.71069 A, mu = 13.83 mm-1, F(000) = 1380, T = 295 K, R = 0.040 for 725 unique observed reflections. Pt has cis square-planar coordination with bond distances Pt-Cl = 2.31 (1), 2.33 (1) A and Pt-N = 2.02 (3) and 1.99 (2) A. The C atoms in the cyclopentylamine ligand, especially C(4), show very high thermal motion. The structure is stabilized by hydrogen bonding involving the ammine ligand and the amino group with the chloro ligands. K[Pt(cyclopentylamine)Cl3].1/2H2O, K+.C5H11Cl3NPt-.0.5H2O, Mr = 434.7, monoclinic, C2/c, a = 33.169 (21), b = 5.881 (4), c = 12.280 (8) A, beta = 102.45 (5) degrees, Z = 8, V = 2339 (3) A3, Dx = 2.468 Mg m3, lambda(Mo K alpha) = 0.71069 A, mu = 13.13 mm-1, F(000) = 1608, T = 295 K, R = 0.043 for 1399 unique observed reflections. Pt has square-planar coordination with Pt-Cl = 2.313 (4), 2.309 (4), 2.304 (4) A, and Pt-N = 2.03 (1) A. The carbon atoms of cyclopentylamine are disordered and two positions were refined for C(1). The compound crystallizes with a molecule of water located on a twofold axis. The water molecule is exceptionally close to the K+ ion [O...K = 2.756 (9) A]. The compound is stabilized by hydrogen bonds between the amino group and one chloro ligand.

Molecular Structure↗
PubMed1988

trans-dichlorobis(di-n-propyl sulfoxide)platinum(II).

[PtCl2(C6H14OS)2], Mr = 534.48, monoclinic, P2(1)/c, a = 9.092 (2), b = 5.696 (2), c = 19.749 (7) A, beta = 110.63 (3) degrees, V = 957.2 (6) A3, Z = 2, D chi = 1.854 Mg m-3, lambda(Mo K alpha) = 0.71069 A, mu(Mo K alpha) = 7.894 mm-1, F(000) = 520, room temperature, R = 0.047 for 1842 unique observed reflections. The Pt atom is located on a center of symmetry. Pt has trans square-planar coordination and the sulfoxide ligands are bonded through their S atoms. The Pt-Cl bond distances are 2.292 (3) A. The Pt-S bond lengths [2.292 (2) A] are significantly longer than the corresponding distances in the cis isomer. The packing consists of layers of molecules parallel to the ab plane.

Models, Molecular↗
PubMed1976

Reactions between nucleosides and platinum dimethylsulfoxide complexes.

Nucleosides (Nuc) react with cis-[Pt(DMSO)2Cl2] in dimethysulfoxide (DMSO) solution, to produce trans-[Pt(DMSO)(Nuc)Cl2], which then isomerize to cis-[Pt(DMSO)(Nuc)Cl2]. They also displace chlorine from K[Pt(DMSO)Cl3] in water to form trans-[Pt(DMSO)(Nuc)Cl2]. K[Pt(inosine)Cl3] and DMSO give in water cis-[Pt(DMSO)(Inosine)Cl2]. The configuration assignment of the compounds was based on chemical reactions, NMR techniques, analytical results, conductivity measurements and comparison with pyridine analogues. Chemical shifts in NMR and coupling constants of the aromatic protons of the nucleosides with 195Pt were used for the assignment of the binding sites of the nucleosides.

Binding Sites↗