0000000001307777
AUTHOR
Christoph Reiter
showing 12 related works from this author
Access to new highly potent antileukemia, antiviral and antimalarial agents via hybridization of natural products (homo)egonol, thymoquinone and arte…
2018
Hybridization of natural products has high potential to further improve their activities and may produce synergistic effects between linked pharmacophores. Here we report synthesis of nine new hybrids of natural products egonol, homoegonol, thymoquinone and artemisinin and evaluation of their activities against P. falciparum 3D7 parasites, human cytomegalovirus, sensitive and multidrug-resistant human leukemia cells. Most of the new hybrids exceed their parent compounds in antimalarial, antiviral and antileukemia activities and in some cases show higher in vitro efficacy than clinically used reference drugs chloroquine, ganciclovir and doxorubicin. Combined, our findings stress the high pot…
The broad-spectrum antiinfective drug artesunate interferes with the canonical nuclear factor kappa B (NF-κB) pathway by targeting RelA/p65.
2015
Infection with human cytomegalovirus (HCMV) is a serious medical problem, particularly in immunocompromised individuals and neonates. The success of standard antiviral therapy is hampered by low drug compatibility and induction of viral resistance. A novel strategy is based on the exploitation of cell-directed signaling inhibitors. The broad antiinfective drug artesunate (ART) offers additional therapeutic options such as oral bioavailability and low levels of toxic side-effects. Here, novel ART-derived compounds including dimers and trimers were synthesized showing further improvements over the parental drug. Antiviral activity and mechanistic aspects were determined leading to the followi…
New artesunic acid homodimers: Potent reversal agents of multidrug resistance in leukemia cells
2012
Abstract To evade the problem of multidrug resistance, hybridization of natural products in dimers is considered as an effective method. After the successful synthesis of three artesunic acid homodimers connected by different types of chemical linkers, we analyzed their activity against human CCRF-CEM and multidrug-resistant p -glycoprotein-overexpressing CEM/ADR 5000 leukemia cells and observed, that multidrug resistant cells were not cross-resistant to the new compounds. Collateral sensitivity was observed for artesunic acid homodimer 2. The obtained results deliver valuable information about the linker’s structure which is required for homodimers to be highly cytotoxic.
New efficient artemisinin derived agents against human leukemia cells, human cytomegalovirus and Plasmodium falciparum: 2nd generation 1,2,4-trioxane…
2015
Abstract In our ongoing search for highly active hybrid molecules exceeding their parent compounds in anticancer, antimalaria as well as antiviral activity and being an alternative to the standard drugs, we present the synthesis and biological investigations of 2nd generation 1,2,4-trioxane-ferrocene hybrids. In vitro tests against the CCRF-CEM leukemia cell line revealed di-1,2,4-trioxane-ferrocene hybrid 7 as the most active compound (IC50 of 0.01 μM). Regarding the activity against the multidrug resistant subline CEM/ADR5000, 1,2,4-trioxane-ferrocene hybrid 5 showed a remarkable activity (IC50 of 0.53 μM). Contrary to the antimalaria activity of hybrids 4–8 against Plasmodium falciparum …
Treatment of Multidrug-Resistant Leukemia Cells by Novel Artemisinin-, Egonol-, and Thymoquinone-Derived Hybrid Compounds
2018
Two major obstacles for successful cancer treatment are the toxicity of cytostatics and the development of drug resistance in cancer cells during chemotherapy. Acquired or intrinsic drug resistance is responsible for almost 90% of treatment failure. For this reason, there is an urgent need for new anticancer drugs with improved efficacy against cancer cells, and with less toxicity on normal cells. There are impressive examples demonstrating the success of natural plant compounds to fight cancer, such as Vinca alkaloids, taxanes, and anthracyclines. Artesunic acid (ARTA), a drug for malaria treatment, also exerts cytotoxic activity towards cancer cells. Multidrug resistance often results fro…
Synthesis and study of cytotoxic activity of 1,2,4-trioxane- and egonol-derived hybrid molecules against Plasmodium falciparum and multidrug-resistan…
2014
Abstract Malaria and cancer cause the death of millions of people every year. To combat these two diseases, it is important that new pharmaceutically active compounds have the ability to overcome multidrug resistance in cancer and Plasmodium falciparum strains. In search of effective anti-cancer and anti-malaria hybrids that possess improved properties compared to their parent compounds, a series of novel 1,2,4-trioxane-based hybrids incorporating egonol and/or ferrocene fragments were synthesized and tested in vitro against P. falciparum strains, CCRF–CEM cells and the multidrug-resistant P-glycoprotein-over-expressing CEM/ADR5000 cells. The most active compounds against P. falciparum stra…
Highly potent artemisinin-derived dimers and trimers: Synthesis and evaluation of their antimalarial, antileukemia and antiviral activities
2015
New pharmaceutically active compounds can be obtained by modification of existing drugs to access more effective agents in the wake of drug resistance amongst others. To achieve this goal the concept of hybridization was established during the last decade. We employed this concept by coupling two artemisinin-derived precursors to obtain dimers or trimers with increased in vitro activity against Plasmodiumfalciparum 3D7 strain, leukemia cells (CCRF-CEM and multidrug-resistant subline CEM/ADR5000) and human cytomegalovirus (HCMV). Dimer 4 (IC50 of 2.6 nM) possess superior antimalarial activity compared with its parent compound artesunic acid(3) (IC50 of 9.0 nM). Dimer5 and trimers6 and 7 disp…
Synthesis of Thymoquinone–Artemisinin Hybrids: New Potent Antileukemia, Antiviral, and Antimalarial Agents
2017
[Image: see text] A series of hybrid compounds based on the natural products artemisinin and thymoquinone was synthesized and investigated for their biological activity against the malaria parasite Plasmodium falciparum 3D7 strain, human cytomegalovirus (HCMV), and two leukemia cell lines (drug-sensitive CCRF-CEM and multidrug-resistant subline CEM/ADR5000). An unprecedented one-pot method of selective formation of C-10α-acetate 14 starting from a 1:1 mixture of C-10α- to C-10β-dihydroartemisinin was developed. The key step of this facile method is a mild decarboxylative activation of malonic acid mediated by DCC/DMAP. Ether-linked thymoquinone–artemisinin hybrids 6a/b stood out as the most…
CCDC 1816140: Experimental Crystal Structure Determination
2018
Related Article: Aysun Çapcı Karagöz, Christoph Reiter, Ean-Jeong Seo, Lisa Gruber, Friedrich Hahn, Maria Leidenberger, Volker Klein, Frank Hampel, Oliver Friedrich, Manfred Marschall, Barbara Kappes, Thomas Efferth, Svetlana B. Tsogoeva|2018|Bioorg.Med.Chem.|26|3610|doi:10.1016/j.bmc.2018.05.041
CCDC 1816139: Experimental Crystal Structure Determination
2018
Related Article: Aysun Çapcı Karagöz, Christoph Reiter, Ean-Jeong Seo, Lisa Gruber, Friedrich Hahn, Maria Leidenberger, Volker Klein, Frank Hampel, Oliver Friedrich, Manfred Marschall, Barbara Kappes, Thomas Efferth, Svetlana B. Tsogoeva|2018|Bioorg.Med.Chem.|26|3610|doi:10.1016/j.bmc.2018.05.041
CCDC 994084: Experimental Crystal Structure Determination
2015
Related Article: Christoph Reiter, Tony Fröhlich, Maen Zeino, Manfred Marschall, Hanife Bahsi, Maria Leidenberger, Oliver Friedrich, Barbara Kappes, Frank Hampel, Thomas Efferth, Svetlana B. Tsogoeva|2015|Eur.J.Med.Chem.|97|164|doi:10.1016/j.ejmech.2015.04.053
CCDC 994085: Experimental Crystal Structure Determination
2015
Related Article: Christoph Reiter, Tony Fröhlich, Maen Zeino, Manfred Marschall, Hanife Bahsi, Maria Leidenberger, Oliver Friedrich, Barbara Kappes, Frank Hampel, Thomas Efferth, Svetlana B. Tsogoeva|2015|Eur.J.Med.Chem.|97|164|doi:10.1016/j.ejmech.2015.04.053