- Overcoming imatinib resistance in chronic myelogenous leukemia cells using non-cytotoxic cell death modulators
-
Recent studies examined the possibility to overcome imatinib resistance in chronic myeloid leukemia (CML) patients by combination therapy with peroxisome proliferator-activated receptor gamma (PPARγ) ligands. Pioglitazone, a full PPARγ agonist, improved the survival of patients by the gradual elimination of the residual CML stem cell pool. To evaluate the importance of the pharmacological profile of PPARγ agonists on the ability to circumvent resistance, the partial PPARγ agonist 4‘-((2-propyl-1H-benzo[d]imidazol-1-yl)methyl)-[1,1’-biphenyl]-2-carboxylic acid, derived from telmisartan, and other related derivatives were investigated. The 4-substituted benzimidazole derivatives bearing a [1,1′-biphenyl]-2-carboxamide moiety sensitized K562-resistant cells to imatinib treatment. Especially the derivatives 18a-f, which did not activate PPARγ to more than 40% at 10 μM, retrieved the cytotoxicity of imatinib in these cells. The cell death modulating properties were higher than that of pioglitazone. It is of interest to note that all novel compounds were not cytotoxic neither on non-resistant nor on resistant cells. They exerted antitumor potency only in combination with imatinib.
- Schoepf, Anna M.,Salcher, Stefan,Obexer, Petra,Gust, Ronald
-
supporting information
(2019/10/22)
-
- Amplification of Trichloroisocyanuric Acid (TCCA) Reactivity for Chlorination of Arenes and Heteroarenes via Catalytic Organic Dye Activation
-
Heteroarenes and arenes that contain electron-withdrawing groups are chlorinated in good to excellent yields (scalable to gram scale) using trichloroisocyanuric acid (TCCA) and catalytic Brilliant Green (BG). Visible-light activation of BG serves to amplify the electrophilic nature of TCCA, providing a mild alternative approach to acid-promoted chlorination of deactivated (hetero)aromatic substrates. The utility of the TCCA/BG system is demonstrated through comparison to other chlorinating reagents and by the chlorination of pharmaceuticals including caffeine, lidocaine, and phenazone.
- Rogers, David A.,Bensalah, Adam T.,Espinosa, Alvaro Tomas,Hoerr, John L.,Refai, Fares H.,Pitzel, Amy K.,Alvarado, Juan J.,Lamar, Angus A.
-
supporting information
p. 4229 - 4233
(2019/06/17)
-
- ALDOSTERONE SYNTHASE INHIBITORS
-
This invention relates to tricyclic triazole analogues of the formula I or their pharmaceutically acceptable salts, wherein the variable are defined herein. The inventive compounds selectively inhibit aldosterone synthetase. This invention also provides for pharmaceutical compositions comprising the compounds of Formula I or their salts as well as to methods for the treatment, amelioration or prevention of conditions that could be treated by inhibiting aldosterone synthetase.
- -
-
Page/Page column 129
(2012/11/13)
-
- Inhibition of Cdc25 phosphatases by indolyldihydroxyquinones
-
Overexpression of the Cdc25A and Cdc25B dual-specificity phosphatases correlates with a wide variety of cancers, making the Cdc25s attractive drug targets for anticancer therapies. However, the search for good lead molecules has been hampered by the reactivity of the active site thiolate anion and the flat solvent-exposed active site region. We describe here the indolyldihydroxyquinones, a new class of inhibitors of Cdc25 that bind reversibly to the active site with submicromolar potency. Structure-activity relationships in the 50 derivatives of the lead molecule 2,5-dihydroxy-3-(1H-indol-3-yl)[1,4]benzoquinone show interesting and consistent trends identifying features required for inhibition of all three isoforms of Cdc25. The compounds do not show time-dependent inhibition, indicating that they form neither covalent adducts with nor oxidize the active site thiol. Our best compounds, 2,5-dihydroxy-3-(7-farnesyl-1H- indol-3-yl)[1,4]benzoquinone and 2,5-dihydroxy-3-(4,6-dichloro-7-farnesyl-1H-indol-3-yl)[1,4]- benzoquinone, are competitive with substrate for the active site and yield Kis of 640 and 470 nM, respectively. Binding of the indolylhydroxyquinones is diminished by three, but not by six other, specific mutations in the active site region. Additionally, the flexible C-terminal tail required for binding of protein substrate is also required for binding derivatives with hydrophobic modifications at the 7-position. The indolyldihydroxyquinones compete effectively with the protein substrate for Cdc25 in vitro and lead to rapid cell death in vivo. Thus, the indolyldihydroxyquinones will serve as useful lead molecules for drug discovery and further cell-based studies on the role of Cdc25s in cell cycle control.
- Sohn, Jungsan,Kiburz, Brendan,Li, Zhitao,Deng, Liu,Safi, Alexias,Pirrung, Michael C.,Rudolph, Johannes
-
p. 2580 - 2588
(2007/10/03)
-
- A convenient copper-catalyzed direct animation of nitroarenes with 9-alkylhydroxylamines
-
O-Alkylhydroxylamines, particularly O-methylhydroxylamine, aminate nitroarenes in the presence of a strong base and a copper catalyst to give aminonitroarenes in good yields, ortho- or para-Animation with respect to the nitro group takes place, and in some cases the ortho-aminated product is preferentially obtained. With 3-substituted nitrobenzenes where the substituent has a lone pair of electrons, preferential amination occurs at the 2-position to give the sterically most congested 3c-f, 14 and 22g.
- Seko, Shinzo,Miyake, Kunihito,Kavvamura, Norio
-
p. 1437 - 1444
(2007/10/03)
-
- Nitroarylamines via the Vicarious Nucleophilic Substitution of Hydrogen: Amination, Alkylamination, and Arylamination of Nitroarenes with Sulfenamides
-
A new reaction of sulfenamides with electrophilic arenes under basic conditions is described. The σ adducts formed from nitroarenes and the anions of sulfenamides undergo elimination of thiol to produce the corresponding o- and/or p-nitroanilines. This reaction is analogous to the known alkylation and hydroxylation of nitroarenes via the vicarious nucleophilic substitution of hydrogen (VNS). The reaction gives access to a wide range of substituted nitroanilines, nitronaphthylamines, and aminoheterocycles. By means of the reaction with N-alkyl- and N-arylsulfenamides, it is possible to obtain N-alkylnitroanilines and nitrodiarylamines. By varying the structure of sulfenamide and the reaction conditions, particularly the nature and concentration of the base, it is possible to control the orientation of animation.
- Makosza, Mieczyslaw,Bialecki, Maciej
-
p. 4878 - 4888
(2007/10/03)
-
- THE REACTION OF ORTHO-SUBSTITUTED AROMATIC AZIDES WITH BORON TRICHLORIDE OR TRIFLUORIDE
-
The reactiont of boron trichloride or trifluoride with ortho-aryl, -diazoaryl, and -arylazoaryl phenyl azides in benzene at room temperature generally gives fused azoles in high yields.Treatment of 2-nitrophenyl azide with boron trichloride mainly affords chlorinated nitroanilines, whereas with boron trifluoride it gives N-o-nitrophenylaniline.In aromatic solvents at 60 deg C in the presence of boron trifluoride-diethyl ether, 2-azidobiphenyl forms carbazole and 2-(arylamino)biphenyls, the formation of which depends greatly upon the nucleophilicity of the solvent used; however, its pseudo-first-order decomposition rate is slightly greater in benzene than in toluene or m-xylene.Under the same conditions, phenyl azide forms diarylamines.The results suggest that singlet nitrenium ions, arising from the corresponding azidetrihalogenoborane complexes by loss of molecular nitrogen, are generally the reactive intermediates.
- Spagnolo, Piero,Zanirato, Paolo
-
p. 2615 - 2620
(2007/10/02)
-
- REGIOSELECTIVITY IN THE REACTION OF NITROQUINOXALINE-N-OXIDES WITH PHOSPHORYL CHLORIDE
-
6-nitro-, 2-methyl-6-nitro- and 2,3-dimethyl-6-nitroquinoxaline have been transformed into their N-oxides by MCPBA in chloroform; the nitro group orients the oxygen atom preferentially to nitrogen atom N1, but the N4:N1 selectivity is diminished in the methylated derivatives.Under the action of POCl3 (the Meisenheimer reaction), the N-oxides of the unmethylated compounds are transformed into chloro-nitroquinoxalines having lost the N-oxide oxygen atom.The orientation of the entering chloride ion is discussed on the basis of electronic effects induced by the N-oxide and nitro groups, and it is suggested that the last step, the elimination of "HPO2Cl2" is a concerted process.
- Nasielski-Hinkens, R.,Vyver, E. Vande,Nasielski, J.
-
p. 663 - 670
(2007/10/02)
-
- Oxidative Cyclizations. VII. Cyclization of 2-Substituted Anilines with Alkaline Hypohalite
-
The Green-Rowe oxidation of 2-nitroanilines with alkaline hypohlorite, to yield benzofuroxans, is demonstrated by studies of the visible spectra of transient intermediates to proceed through N-chlorination and a singlet nitrene.Two variations on the route to the nitrene are possible.The cyclization step is represented as an internal capture of the nitrene by the ortho substituent, and on this basis the Green-Rowe oxidative cyclization is now extended to anilines whose ortho substituent is benzoyl or phenylazo.It is not however successful for ortho phenyl.Azo compounds were observed as byproducts in some of these reactions, and are shown to arise via N,N-dichloroanilines.
- Dyall, Leonard K.
-
p. 2013 - 2026
(2007/10/02)
-
- The reaction of Organic Azides with Boron Trichloride: A New Simple Route for the Production of Fused Heterocycles Containing Nitrogen
-
The reaction of boron trichloride with an ortho-aryl and ortho-diazoaryl phenyl azides at room temperature yielded fused azoles via 1,5-cyclization of a probable singlet nitrenium ion intermediate, arising from displacement of molecular nitrogen from the azido group.
- Zanirato, Paolo
-
p. 1065 - 1067
(2007/10/02)
-