- Combretastatin A-4 analogues with benzoxazolone scaffold: Synthesis, structure and biological activity
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In order to design and synthesize a new class of heterocyclic analogues of natural combretastatin A-4 and its synthetic derivative AVE8062, the benzoxazolone ring was selected as a scaffold for a bioisosteric replacement of the ring B of both molecules. A library of 28 cis- and trans-styrylbenzoxazolones was obtained by a modified Wittig reaction under Boden's conditions. Structures of the newly synthesized compounds bearing the 3,4,5-trimethoxy-, 3,4-dimethoxy-, 3,5-dimethoxy-, and 4-methoxystyryl fragment at position 4, 5, 6 or 7 of benzoxazolone core were determined on the basis of spectral and X ray data. The in vitro cytotoxicity of styrylbenzoxazolones against different cell lines was examined. Stilbene derivative 16Z, (Z)-3-methyl-6-(3,4,5-trimethoxystyryl)-2(3H)-benzoxazolone, showed highest antiproliferative potential of the series, with IC50 of 0.25 μM against combretastatin resistant cell line HT-29, 0.19 μM against HepG2, 0.28 μM against EA.hy926 and 0.73 μM against K562 cells. Furthermore, the results of flow cytometric analysis confirmed that 16Z induced cell cycle arrest in G2/M phase in the cell lines like combretastatin A-4. This arrest is followed by an abnormal exit of cells from mitosis without cytokinesis into a pseudo G1-like multinucleate state leading to late apoptosis and cell death. Accordingly, synthetic analogue 16Z was identified as the most promising potential anticancer agent in present study, and was selected as lead compound for further detailed investigations.
- Gerova, Mariana S.,Stateva, Silviya R.,Radonova, Elena M.,Kalenderska, Rositsa B.,Rusew, Rusi I.,Nikolova, Rositsa P.,Chanev, Christo D.,Shivachev, Boris L.,Apostolova, Margarita D.,Petrov, Ognyan I.
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p. 121 - 133
(2016/05/24)
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- Ramoplanin derivatives possessing antibacterial activity
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Novel ramoplanin derivatives are disclosed. These ramoplanin derivatives exhibit antibacterial activity. As the compounds of the subject invention exhibit potent activities against gram positive bacteria, they are useful antimicrobial agents. Methods of synthesis and of use of the compounds are also disclosed.
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Page/Page column 68
(2010/11/23)
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- VLA-4 INHIBITORS
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The present invention relates to a compound represented by the following formula (I): (wherein, W represents WA-A1 -WB - (in which, WA is substituted or unsubstituted aryl, etc., A1 is -NR1-, single bond, -C(O)-, etc., and WB is substituted or unsubstituted arylene, etc.), R is single bond, -NH-, -OCH2-, alkenylene, etc., X is -C(O) -CH2-, etc., and M is, for example, the following formula: (in which, R11, R12 and R13 each independently represents hydrogen, hydroxyl, amino, halogen, etc., R14 is hydrogen or lower alkyl, Y represents -CH2-O-, etc., Z is substituted or unsubstituted arylene, etc., A2 is single bond, etc, and R10 is hydroxyl or lower alkoxy)), or salt thereof; and a medicament containing the same. This compound or salt thereof selectively inhibits binding of cell adhesion molecules to VAL-4 and exhibits high bioavailability so that it is useful as a preventive and/or remedy for inflammatory diseases, autoimmune diseases, metastasis, bronchial asthma, rhinostenosis, diabetes, and the like.
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- Acid-catalyzed amino-migration of O-phenylhydroxylamines
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The mechanism of amino-migration of O-phenylhydroxylamine (1a) was studied. It was found that 1 rearranges to give 2-aminophenol (50%) and 4-aminophenol (7%) in trifluoroacetic acid (TFA). The predominance of the ortho rearrangement of 1 clearly distinguishes this process from the Bamberger rearrangement. From cross-coupling experiments employing stable isotopes, it was clarified that the ortho rearrangement proceeds intramolecularly and the para rearrangement involves both intra- and intermolecular processes. Good first-order kinetics were obtained for the rearrangement. The Hammett plot (σ+) with a large negative slope (ρ = -7.8) indicates that initial heterolytic N-O bond cleavage of 1 occurs and generates a positive charge on the oxygen atom with considerable delocalization into the aromatic ring. An ion-molecule pair involving a phenoxenium ion and an ammonia molecule as an intermediate rationalizes all of the results. In this pair, intramolecular combination to the ortho position proceeds preferentially over that to the para position. Formation of catechol and hydroquinone can be explained in terms of nucleophilic attack of TFA on the phenoxenium ion in a solvent-separated pair.
- Haga, Naoki,Endo, Yasuyuki,Kataoka, Ken-Ichiro,Yamaguchi, Kentaro,Shudo, Koichi
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p. 9795 - 9806
(2007/10/02)
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- The Mechanism for Interconversion of Stereoisomers in N-(2,3-Dihydro-2-oxobenzoxazol-3-yl)- and N-(1,2-Dihydro-2-oxoquinolin-1-yl)-N-1-methylallylarenesulphenamides
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Stereoisomers of the quinolone and benzoxazolinone-substituted sulphenamides (1) and (2) are interconverted by formal rotation around their N-N (chiral) axes.Two alternative pathways which could result in net rotation have been tested.Neither epimerisation at C-1 via a route involving sigmatropic rearrangement nor radical dissociation-recombination have been found to contribute significantly to interconversion of the stereoisomers.The retarded rate of stereoisomer interconversion in the 4-methylbenzoxazolinone-sulphenamide (16) by comparison with (2) suggests that this process in (2) occurs by simple N-N bond rotation and a similar conclusion has been drawn in the case of (1) by comparison with the rate of racemisation of (19).
- Atkinson, Robert S.,Judkins, Brian D.
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p. 509 - 513
(2007/10/02)
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- Thieno[3,4-b][1,5]benzoxazepin-10-ones and thieno[3,4-b][1,5]benzothiazepin-10-ones
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This disclosure describes novel substituted thieno[3,4-b][1,5]benzoxazepin-10 (9H)-ones and thieno[3,4-b][1,5]benzothiazepin-10(9H)-ones which are useful as intermediates for the preparation of 10-[4-(substituted)-1-piperazinyl]thieno[3,4-b][1,5]benzoxaze
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- 10-(Piperazinyl)thieno[3,4-b][1,5]benzoxazepines and 10-(piperazinyl)thieno[3,4-b][1,5]benzothiazepines
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This disclosure describes 10-[4-(substituted)-1-piperazinyl]thieno[3,4-b][1,5]benzoxazepines and 10-[4-(substituted-1-piperazinyl]thieno[3,4-b][1,5]benzothiazepines useful as anti-psychotic or neuroleptic agents.
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