106 research outputs found
2,2′-[1,1′-(Octane-1,8-diyldioxydinitrilo)diethylidyne]diphenol
The title compound, C24H32N2O4, has a crystallographic inversion centre at the mid-point of the central C—C bond. At each end of the molecule, intramolecular O—H⋯N hydrogen bonds generate six-membered S(6) ring motifs. The crystal structure is stabilized by pairs of weak intermolecular C—H⋯O hydrogen bonds that link neighbouring molecules into R
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2(40) ring motifs, which in turn form infinite one-dimensional supramolecular ribbon structures
Bis[(E)-4-bromo-2-(ethoxyiminomethyl)phenolato-κ2 N,O 1]copper(II)
The title compound, [Cu(C9H9BrNO2)2], is a centrosymmetric mononuclear copper(II) complex. The Cu atom is four-coordinated in a trans-CuN2O2 square-planar geometry by two phenolate O and two oxime N atoms from two symmetry-related N,O-bidentate (E)-4-bromo-2-(ethoxyiminomethyl)phenolate oxime-type ligands. An interesting feature of the crystal structure is the centrosymmetric intermolecular Cu⋯O interaction [3.382 (1) Å], which establishes an infinite chain structure along the b axis
4-({4-[1-(Methoxyimino)ethyl]anilino}(phenyl)methylene)-3-methyl-2-phenyl-1H-pyrazol-5(4H)-one
In the title compound, C26H24N4O2, the dihedral angles between the central pyrazole ring and the other three benzene rings are 40.02 (3), 77.51 (5) and 55.72 (3)°. A strong intramolecular N—H⋯O hydrogen bond forms a six-membered ring with an S(6) motif. In the crystal structure, a weak intermolecular C—H⋯N interaction with graph-set motif R
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2(8) and C—H⋯O hydrogen bonds link each molecule to three others, forming an infinite two-dimensional supramolecular structure
SHP-2 tyrosine phosphatase inhibits p73-dependent apoptosis and expression of a subset of p53-target genes induced by the green tea polyphenol EGCG
Green tea polyphenol, epigallocatechin-3-gallate (EGCG) differentially regulates the cellular growth of cancer cells in a p53-dependent manner through apoptosis and/or cell cycle arrest. In an effort to further elucidate the mechanism of differential growth regulation by EGCG, we have investigated the role of the tyrosine phosphatase, SHP-2. Comparing the responses of mouse embryonic fibroblasts (MEFs), expressing either WT or functionally inactive/truncated SHP-2, we find that inactivation of SHP-2 remarkably sensitizes cells to EGCG-mediated killing. MEFs lacking functional SHP-2 undergo massive apoptosis upon treatment with EGCG. By comparing gene expression profiles, we have identified a set of transcriptional targets of p53 that are differentially modulated in cells undergoing apoptosis. Western blot and real-time PCR analyses of a select group of genes further confirm that the expression is SHP-2-dependent. Similar observations were made in MEFs lacking p53, confirming that the expression of these “p53 target genes” is p53-independent. In addition, EGCG treatment induced the expression of p73 mRNA and protein in both cell types, but not p63. Inactivation of p73 in cells expressing nonfunctional SHP-2 markedly inhibited apoptosis and p53 target gene expression. Although phosphorylation of JNK is differentially regulated by SHP2, it was found to be dispensable for EGCG-induced apoptosis and p53 target gene expression. Our results have identified SHP-2 as a negative regulator of EGCG-induced-apoptosis and have identified a subset of p53 target genes whose expression is paradoxically not mediated by p53 but by one of its family members, p73
{2,2′-[1,1′-(Ethylenedioxydinitrilo)diethylidyne]di-1-naphtholato}copper(II)
The title complex, [Cu(C26H22N2O4)], is isostructural with its Ni analogue. All intramolecular distances and angles are very similar for the two structures, whereas the packing of the molecules, including C—H⋯O and C—H⋯π interactions, are slightly different
2,2′-[1,1′-(Decane-1,10-diyldioxydinitrilo)diethylidyne]diphenol
The salen-type bis-oxime title compound, C26H36N2O4, lies about a crystallographic inversion centre. Classical intramolecular O—H⋯N hydrogen bonds generate two S(6) ring motifs. In the crystal structure, pairs of weak intermolecular C—H⋯O hydrogen bonds link adjacent molecules into an infinite one-dimensional supramolecular structure
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