133141-63-6Relevant academic research and scientific papers
Synthesis and Characterization of Telmisartan-Derived Cell Death Modulators to Circumvent Imatinib Resistance in Chronic Myeloid Leukemia
Schoepf, Anna M.,Salcher, Stefan,Hohn, Verena,Veider, Florina,Obexer, Petra,Gust, Ronald
, p. 1067 - 1077 (2020/05/25)
New strategies to eradicate cancer stem cells in chronic myeloid leukemia (CML) include a combination of imatinib with peroxisome proliferator-activated receptor gamma (PPARγ) ligands. Recently, we identified the partial PPARγ agonist telmisartan as effective sensitizer of resistant K562 CML cells to imatinib treatment. Here, the importance of the heterocyclic core on the cell death-modulating effects of the telmisartan-derived lead 4′-((2-propyl-1H-benzo[d]imidazol-1-yl)methyl)-[1,1′-biphenyl]-2-carboxylic acid (3 b) was investigated. Inspired by the pharmacodynamics of HYL-6d and the selective PPARγ ligand VSP-51, the benzimidazole was replaced by a carbazole or an indole core. The results indicate no correlation between PPARγ activation and sensitization of resistant CML cells to imatinib. The 2-COOH derivatives of the carbazoles or indoles achieved low activity at PPARγ, while the benzimidazoles showed 60-100 % activation. Among the 2-CO2CH3 derivatives, only the ester of the lead (2 b) slightly activated PPARγ. Sensitizing effects were further observed for this non-cytotoxic 2 b (80 % cell death), and to a lesser extent for the lead 3 b or the 5-Br-substituted ester of the benzimidazoles (5 b).
Overcoming imatinib resistance in chronic myelogenous leukemia cells using non-cytotoxic cell death modulators
Schoepf, Anna M.,Salcher, Stefan,Obexer, Petra,Gust, Ronald
, (2019/10/22)
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.
New telmisartan-derived PPARγ agonists: Impact of the 3D-binding mode on the pharmacological profile
Obermoser, Victoria,Urban, Margarethe E.,Murgueitio, Manuela S.,Wolber, Gerhard,Kintscher, Ulrich,Gust, Ronald
, p. 138 - 152 (2016/08/30)
In previous studies, the 4′-((2-propyl-1H-benzo[d]imidazol-1-yl)methyl)-[1,1′-biphenyl]-2-carboxylic acid was identified as pharmacophoric core for PPARγ activation. In this structure-activity relationship study the C2-alkyl chain was elongated and the 2-COOH group was changed to a carbamide/carbonitrile or shifted to the 3- or 4-position. Furthermore, the benzo[d]imidazole was exchanged by 2,3-dihydrobenzo[d]thiazole or 1H-indole. C2-propyl derivatives showed the profile of partial agonists, while elongation of the C2-chain to that of an n-heptyl group or a 4-COOH shift changed the pharmacological profile to that of a potent full agonist. This finding can be explained by binding to the LBD in different ligand conformations. Two anchoring points (Tyr473 and Arg288) exist in the LBD, which have to be contacted to achieve receptor activation. In a crystal violet chemosensitivity assay using COS-7?cells and LNCaP cells expressing PPARγ only the carbamide derivatives influenced the cell growth, independently on the presence of the PPARγ. Therefore, receptor mediated cytotoxicity can be excluded.
Characterization of new PPARγ agonists: Benzimidazole derivatives - Importance of positions 5 and 6, and computational studies on the binding mode
Goebel, Matthias,Wolber, Gerhard,Markt, Patrick,Staels, Bart,Unger, Thomas,Kintscher, Ulrich,Gust, Ronald
experimental part, p. 5885 - 5895 (2010/10/01)
In this and previous studies we investigated the importance of partial structures of Telmisartan on PPARγ activation. The biphenyl-4-ylmethyl moiety at N1 and residues at C2 of the central benzimidazole were identified to be essential for receptor activation and potency of receptor binding. Now we focused our attention on positions 5 and 6 of the central benzimidazole and introduced bromine (3b-5/6, 3c), phenylcarbonyl (3d-5/6), hydroxy(phenyl)methyl (3g-5/6), hydroxymethyl (3h-5/6) and formyl (3i) groups. The selection of these moieties was inspired by the structure of Losartan and its metabolite EXP3179. In order to increase the hydrophobicity of the central part of the molecule, the benzimidazole was exchanged by a naphtho[2,3-d]imidazole (5). The compounds 3a-3i and 5 were tested in a differentiation assay using 3T3-L1 preadipocytes and a luciferase assay using COS-7 cells, transiently transfected with pGal4-hPPARγDEF, pGal5-TK-pGL3 and pRL-CMV, as established models for the assessment of cellular PPARγ activation. An enhanced effect on PPARγ activation could be observed if lipophilic moieties are introduced in these positions. 4′-[(2-Propyl-1H-naphtho[2,3-d]imidazol-1-yl)methyl]biphenyl-2- carboxylic acid (5) was identified as the most potent compound with an EC 50 of 0.26 μM and the profile of a full agonist. Together with compounds of the former structure-activity relationship study (position 2-substituted benzimidazole derivatives 4a-4j), the binding mode of Telmisartan and its derivatives have been analyzed in 3D pharmacophore-driven docking experiments.
Benzimidazoles and medicaments containing these compounds
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, (2008/06/13)
The invention relates to benzimidazoles of the formula STR1 in which R1 to R2 are as defined in claim 1, 1 and 3 isomer mixtures thereof and addition salts thereof which have valuable properties. In particular, the novel compounds ar
