- Cyclosporin derivatives
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The present invention relates to novel cyclosporin derivatives that do not cross the cellular membrane. The compounds according to the invention are used in medicine, more particularly in the treatment/diagnosis of acute and chronic inflammatory diseases,
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Page/Page column 84
(2016/10/17)
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- Triptycene-based, carboxylate-bridged biomimetic diiron(II) complexes
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A triptycene-based bis(benzimidazole) ester ligand, L3, was designed to enhance the electron-donating ability of the heterocyclic nitrogen atoms relative to those of the first-generation bis(benzoxazole) analogs, L1 and L2. A convergent synthesis of L3 was designed and executed. Three-component titration experiments using UV/Vis spectroscopy revealed that the desired diiron(II) complex could be obtained with a 1:2:1 ratio of L3/Fe(OTf)2(MeCN) 2/external carboxylate reactants. X-ray crystallographic studies of two diiron complexes derived in this manner from L3 revealed their formulas to be [Fe2L3(μ-OH)(μ-O2CR)(OTf)2], where R = 2,6-bis(p-tolyl)phenyl (7) or triphenylmethyl (8). The structures are similar to that of a diiron complex derived from L1, [Fe2L1(μ-OH)(μ- O2CArTol)(OTf)2] (9), a notable difference being that, in 7 and 8, the geometry at iron more closely resembles square-pyramidal than trigonal-bipyramidal. Moessbauer spectroscopic analyses of 7 and 8 indicate the presence of high-spin diiron(II) cores. These results demonstrate the importance of substituting benzimidazole for benzoxazole for assembling biomimetic diiron complexes with syn disposition of two N-donor ligands, as found in O2-activating carboxylate-bridged diiron centers in biological systems. Copyright
- Li, Yang,Soe, Chan Myae Myae,Wilson, Justin J.,Tuang, Suan Lian,Apfel, Ulf-Peter,Lippard, Stephen J.
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p. 2011 - 2019
(2013/06/05)
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- Potential Antitumor Agents. 59. Structure-Activity Relationships for 2-Phenylbenzimidazole-4-carboxamides, a New Class of "Minimal" DNA-Intercalating Agents Which May Not Act via Topoisomerase II
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A series of substituted 2-phenylbenzimidazole-4-carboxamides has been synthesized and evaluated for in vitro and in vivo antitumor activity.These compounds represent the logical conclusion to our search for "minimal" DNA-intercalating agents with the lowest possible DNA-binding constants.Such "2-1" tricyclic chromophores, of lower aromaticity than the structurally similar 2-phenylquinolines, have the lowest DNA binding affinity yet seen in the broad series of tricyclic carboxamide intercalating agents.Despite very low in vitro cytotoxicities, several of the compoundshad moderate levels of in vivo antileukemic effects.However, the most interesting aspect of their biological activity was the lack of cross-resistance shown to an amsacrine-resistant P388 cell line, suggesting that these compounds may not express their cytotoxicity via interaction with topoisomerase II.
- Denny, William A.,Rewcastle, Gordon W.,Baguley, Bruce C.
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p. 814 - 819
(2007/10/02)
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