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11. Metal bisthiophenedithiolates as building blocks in molecular materials

Author

Belo, D., primary, Figueira, M. J., additional, Mendonça, J., additional, Alves, H., additional, Santos, I. C., additional, Lopes, E. B., additional, Pereira, L. C., additional, Duarte, M. T., additional, Gama, V., additional, Henriques, R. T., additional, Almeida, M., additional, Rovira, C., additional, and Veciana, J., additional

Published
2004
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31. Isoprenoid compounds from Euphorbia portlandica. X-ray structure of lupeportlandol, a new lupane triterpene

Author

Madureira, A. M., Duarte, M. T., Piedade, M. F. M., Jose Ascenso, Ferreira, M. -J U., and Repositório da Universidade de Lisboa

Subjects
triterpenes, Chemistry, Multidisciplinary, lupane, Euphorbia portlandica, steroids, X-ray diffraction
Abstract

Phytochemical survey of the Me2CO extracts of the whole dried plant Euphorbia portlandica led to the isolation of a new pentacyclic triterpene alcohol, with the lupane skeleton, named lupeportlandol. Its structure was established as 3alpha-hydroxy-19alphaH-lup-20(29)-ene. The known pentacyclic triterpene glutinol and the steroid b-sitostenone were also isolated. The characterization of the new compound and its acetylated derivative was based on spectroscopic methods and an X-ray diffraction analysis. Lupeportlandol acetate was inactive in cytotoxicity assays in vitro against three human tumor cell lines: MCF-7 (breast cancer), NCI-H460 (non-small cell lung cancer) and SF-268 (CNS cancer). O estudo fitoquímico dos extratos de Me2CO da planta inteira e seca de Euphorbia portlandica levou ao isolamento de um novo álcool triterpênico pentacíclico, com o esqueleto do lupano, designado por lupeportlandol. A sua estrutura foi estabelecida como 3alfa-hidroxi-19alfaH-lup-20(29)-eno. Foram também isolados os já conhecidos triterpeno pentacíclico glutinol e o esteróide beta-sitostenona. A caracterização do novo composto e do seu derivado acetilado foi baseada em métodos espectroscópicos e numa análise de difração de raio-X. O acetato de lupeportlandol mostrou-se inativo em ensaios de citotoxicidade in vitro contra três linhagens de células tumorais humanas: MCF-7 (câncer da mama), NCI-H460 (câncer do pulmão) e SF-268 (câncer do SNC).

34. Decamethyl­ferrocenium bis­(2-oxo-1,3-dithiole-4,5-dithiolato-κ2 S4, S5)nickelate(III) tetra­hydro­furan solvate.

Author

Duarte, M. T., Gama, V., Rabaça, S., and Santos, I. C.

Subjects
*CRYSTALS, *CATIONS, *MOLECULAR structure, *CRYSTALLIZATION, *ORGANOMETALLIC compounds
Abstract

The title compound, [Fe(C10H15)2][Ni(C3OS4)2]·C4H8O or [Fe(Cp*)2][Ni(dmio)2]·THF, where [Fe(Cp*)2]+ is the deca­methyl­ferrocenium cation, dmio is the 2-oxo-1,3-dithiole-4,5-dithiol­ate dianion and THF is tetra­hydro­furan, crystallizes with two independent half-anion units [one Ni atom is at the centre of symmetry ( , , 0) and the other is at the centre of symmetry ( , 0, )], one cation unit (located in a general position) and one THF solvent mol­ecule in the asymmetric unit. The crystal structure consists of two-dimensional layers composed of parallel mixed chains, where pairs of cations alternate with single anions. These layers are separated by sheets of anions and THF mol­ecules. [ABSTRACT FROM AUTHOR]

Published
2006
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37. Decamethylferrocenium bis(2-oxo-1,3-dithiole-4,5-dithiolato-kappa(2)S(4),S(5))nickelate(III) tetrahydrofuran solvate.

Author

Rabaça S, Santos IC, Duarte MT, and Gama V

Abstract

The title compound, [Fe(C(10)H(15))(2)][Ni(C(3)OS(4))(2)].C(4)H(8)O or [Fe(Cp*)(2)][Ni(dmio)(2)] x THF, where [Fe(Cp*)(2)](+) is the decamethylferrocenium cation, dmio is the 2-oxo-1,3-dithiole-4,5-dithiolate dianion and THF is tetrahydrofuran, crystallizes with two independent half-anion units [one Ni atom is at the centre of symmetry ({1/2}, {1/2}, 0) and the other is at the centre of symmetry ({1/2},0, {1/2})], one cation unit (located in a general position) and one THF solvent molecule in the asymmetric unit. The crystal structure consists of two-dimensional layers composed of parallel mixed chains, where pairs of cations alternate with single anions. These layers are separated by sheets of anions and THF molecules.

Published
2006
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38. Trans-[N,N'-Bis(salicydene)cyclohexane-1,2-diaminato]nickel(II)-chloroform (1/1).

Author

de Castro B, Freire C, Duarte MT, Minas Da Piedade MF, and Santos IC

Abstract

In the title complex, trans-(2,2'-[cyclohexane-1,2-diylbis(nitrilomethylidyne)]diphenolato-kappa(4)O,N,N',O')nickel(II)-chloroform (1/1), [Ni(C(20)H(20)N(2)O(2))].CHCl(3), the Ni atom has a square-planar geometry, slightly tetrahedrally distorted. The Ni-N and Ni-O bonding distances are within the expected ranges for Ni-Schiff base derivatives. The diimine bridge has a gauche conformation with the cyclohexyl ring almost coplanar with the NiN(2)O(2) plane. The complex molecules pack in dimers with an Ni.Ni distance of 3.59 (1) A and form a three-dimensional structure displaying a herring-bone configuration. Channels are occupied by solvent molecules, which are involved in C-H.O hydrogen bonds with the ligand O atoms.

Published
2001
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