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A novel transition metal complex, Venus flytrap cluster (VFC), is described for the preparation of radio-labeled antibodies. VFC contained 57Co, which was held tightly between the faces of two covalently bridged carborane ligands by cluster bonding of the metal with appropriate ligand orbitals. Anti-carcinoembryonic antigen monoclonal antibody T84.66 was conjugated to 57Co-VFC with full retention of immunological activity. Biodistribution studies in nude mice bearing carcinoembryonic antigen-producing tumors showed excellent tumor localization of 57Co-VFC-T84.66. The accumulation of radionuclide in normal liver was low and independent of dose, which may reflect the stability of the radionuclide complex. These results presage the use of VFC systems for binding transition metals that are clinically useful for radioimmunodiagnosis and radioimmunotherapy.

The closo-[B12H12-n(OH)n]2- (n = 1-4) ions have been synthesized by the reaction of cesium dodecahydro-closo-dodecaborate(2-), Cs21, with aqueous sulfuric acid. Variation of the reaction temperature, time, and acid concentration results in the stepwise introduction of from one to four hydroxyl groups. Each individual hydroxylation step proceeds regioselectively, affording only one isomer per step. Further substitution of the hydroxylated cluster preferentially takes place at a B-H vertex meta to a B-OH vertex. The closo-[B12H12-n(OH)n]2- (n = 1-4) species, designated 2-5, respectively, are characterized by one- and two-dimensional 11B NMR spectroscopy, IR spectroscopy, and high-resolution fast atom bombardment (FAB) mass spectrometry. A rationale that qualitatively explains the influence of the hydroxyl group on the chemical shifts of the individual boron vertices is developed. Furthermore, the solid state structures of closo-[B12H11(OH)]2-, 2, and closo-1,7-[B12H10(OH)2]2-,3, are determined by X-ray diffraction. Crystallographic data are as follows: For [MePPh3](2)2, monoclinic, space group P2(1)/n, a = 890.1(5) pm, b = 1814(1) pm, c = 1270.5(7) pm, beta = 101.66(2) degrees, Z = 2, R = 0.055; for [MePPh3](2)3, monoclinic, space group P2(1)/n, a = 887.6(4) pm, b = 1847.2(8) pm, c = 1271.1(5) pm, beta = 101.17(1) degrees, Z = 2, R = 0.065. In addition, synthetic routes to O-derivatized species of the anions 2-5 such as closo-[B12H11(OTiCpCl2)]2-, 7, closo-1,7-[B12H10(OTiCpCl2)2]2-, 8, closo-1,7,9-[B12H9(OTiCpCl2)3]2-, 9, closo-[B12H11(OCONHPh)]2-, 10, and closo-1,7-[B12H10(OSO2Me)2]2-, 11, are described. The crystal structures of 7 and 11 are determined by single-crystal X-ray diffraction. Crystallographic data are as follows: For [MePPh3](2)7, monoclinic, space group Cc, a = 2530.5(2) pm, b = 1653.3(1) pm, c = 1281.3(1) pm, beta = 118.79(2) degrees, Z = 4, R = 0.085; for [HPy](2)11, monoclinic, space group P2(1)/n, a = 1550.9(8) pm, b = 993.1(5) pm, c = 1726.5(9) pm, beta = 112.36(2) degrees, Z = 4, R = 0.061.

Two cyclic Lewis acidic receptors, namely B-hexamethyl-9-mecuracarborand-3, [9,12-(CH3 )2 -C2 B10 H8 Hg]3 , each host a single water molecule. A benzene molecule is situated between the two complexed water molecules in a sandwich fashion that suggests there is O-H⋅⋅⋅π hydrogen bonding.

No explosion, but per-B-hydroxylation occurs if the icosahedral boron hydrides [closo-B12 H12 ](2-) (see picture), [closo-CB11 H12 ](-) , or closo-1,12-(CH2 OH)2 -1,12-C2 B10 H10 are refluxed in 30 % hydrogen peroxide. Thus, the three isoelectronic species [closo-B12 (OH)12 ](2-) , [closo-1-H-1-CB11 (OH)11 ](-) , and closo-1,12-H2 -1,12-C2 B10 (OH)10 were obtained. ○=BH, ○=BOH.

Le complexe du titre cristallise dans le systeme monoclinique, groupe P2 1 /n et sa structure est affinee jusqu'a R=0,050. La molecule est constituee d'un triangle d'atomes Os ponte sur son cote le plus long par un groupe acetyl et un atome d'hydrogene

The Schiff base disulphide ligands N,N′-[1,1′-dithiobis(phenylene)]bis(salicylideneimine), designated hereunder as H2salps, and N,N′-[1,1′-dithiobis(ethylene)]bis(salicydeneimine), designated hereunder as H2sales, react with nickel(II) acetate tetrahydrate in methanol giving two mononuclear complexes: [Ni(salps)(MeOH)] · MeOH and [Ni(sales)], respectively. These complexes have been characterized by spectral, magnetic and electrochemical methods. The structure of [Ni(salps)(MeOH)] · MeOH has been determined by X-ray diffraction analysis. This complex crystallizes in the triclinic crystal system, space group P1, Z = 2, a = 9.476(1), b = 11.297(3) and c = 13.215(3) A, α = 106.66(1), β = 97.10(1), and γ = 99.94(1)° and V = 1312.3(3) A3. The refinement converged to R = 0.034 and Rw = 0.045 based on 2599 reflections with I ⪢ 3σ(I). The salps functions as a quinquedentate ligand coordinating through the two phenolate oxygen atoms the two imine nitrogen atoms and only one of the disulphide sulphur atoms. The sixth coordination site is occupied by the oxygen atom from a methanol molecule. The octahedron core, NiN2O3S, is highly distorted as indicated by the range in bond distances (from 2.063(3) to 2.531(1) A) and angles (from 79.47(8) to 100.4(1)°). The Ni bond distance is 2.531(1) A, while the SS bond distance is 2.066(1) A. On the other hand, the spectral and magnetic properties of [Ni(sales)] suggest a square-pyramidal structure with a NiS bond. The complexes show non-conjugated and irreversible redox processes in cyclic voltammetry, in DMF. The processes at − 1.30 and − 1.43 V have been attributed to the reduction of the disulphide group, whereas the oxidation process at ca + 0.74 V has been attributed to the nickel(II) oxidation.

Determination de la structure cristalline du compose diphenylphosphino-2 phenyl-3 triphenylphosphine-3 dicarba-1,2 rhoda-3-closo-dodecaborane(11)-benzene

Preparation d'un complexe du thallium et du gallium du type Tl [R] ou R est un spirobi-3,3' dicarba-1,2 galla-3 dodecaborane (11) a partir de chlorure de gallium (III) et de Tl 2 [C 2 -7,8BgH 11 ]

Crystal structure and conformation are determined for the cavitands (II) (space group P1, Z=2) and (V)·CH2Cl2 or (V)·EtOH ( P21/n, Z=4), as well as the caviplex (V)·CsClO4 (Pnam, Z=4).