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Antiprotozoal Activity
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Reto Brun – One of the best experts on this subject based on the ideXlab platform.
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Alkamides from Anacyclus pyrethrum L. and Their in Vitro Antiprotozoal Activity.
Molecules, 2017Co-Authors: J B Althaus, Marcel Kaiser, Reto Brun, Claudine Malyszek, Thomas J. SchmidtAbstract:In our ongoing study to evaluate the Antiprotozoal Activity of alkamides from Asteraceae, a dichloromethane extract from the roots of Anacyclus pyrethrum L. showed a moderate in vitro Activity against the NF54 strain of Plasmodium falciparum and against Leishmania donovani (amastigotes, MHOM/ET/67/L82 strain). Seven pure alkamides and a mixture of two further alkamides were isolated by column chromatography followed by preparative high performance liquid chromatography. The alkamides were identified by mass- and NMR-spectroscopic methods as tetradeca-2E,4E-dien-8,10-diynoic acid isobutylamide (anacycline, 1), deca-2E,4E-dienoic acid isobutylamide (pellitorine, 2), deca-2E,4E,9-trienoic acid isobutylamide (3), deca-2E,4E-dienoic acid 2-phenylethylamide (4), undeca-2E,4E-dien-8,10-diynoic acid isopentylamide (5), tetradeca-2E,4E,12Z-trien-8,10-diynoic acid isobutylamide (6), and dodeca-2E,4E-dien acid 4-hydroxy-2-phenylethylamide (7). Two compounds—undeca-2E,4E-dien-8,10-diynoic acid 2-phenylethylamide (8) and deca-2E,4E-dienoic acid 4-hydroxy-2-phenylethylamide (9)—were isolated as an inseparable mixture (1:4). Compounds 3, 4, and 5 were isolated from Anacyclus pyrethrum L. for the first time. While compounds 4 and 5 were previously known from the genus Achillea, compound 3 is a new natural product, to the best of our knowledge. All isolated alkamides were tested in vitro for Antiprotozoal Activity against Plasmodium falciparum, Trypanosoma brucei rhodesiense, Trypanosoma cruzi, and Leishmania donovani and for cytotoxicity against L6 rat skeletal myoblasts.
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Antiprotozoal Activity of dehydroabietic acid derivatives against Leishmania donovani and Trypanosoma cruzi
MedChemComm, 2016Co-Authors: Mikko Vahermo, Reto Brun, Marcel Kaiser, Sara Krogerus, Abdelmajeed Nasereddin, Charles L. Jaffe, Jari Yli-kauhaluoma, Vânia M. MoreiraAbstract:Derivatives of dehydroabietic acid bearing different amino acids scaffolds have potent Antiprotozoal Activity against Leishmania donovani and Trypanosoma cruzi, with good to high selectivity, and can therefore be regarded as good models for further development into new drugs to fight leishmaniasis and Chagas disease. Several of the tested compounds were able to kill parasites residing inside cells, with IC50 values ranging from 2.3 to 9 μM (L. donovani) and 1.4 to 5.8 μM (T. cruzi), reflecting their ability to fight these infections at the relevant stage responsible for disease. One of the compounds, bearing a 3-pyridyl-D-alanine side chain, was 1.5-fold more potent against T. cruzi amastigotes residing in L6 cells than the reference compound benznidazole.
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Antiprotozoal Activity of bicycles featuring a dimethylamino group at their bridgehead.
Bioorganic & Medicinal Chemistry, 2016Co-Authors: Johanna Faist, Reto Brun, Marcel Kaiser, Werner Seebacher, Robert Saf, Robert WeisAbstract:Several dimethylamino-derivatives of the new compound-class 3-azabicyclo[3.2.2]nonanes were prepared. For better comparison of Activity also a few analogues of bicyclo[2.2.2]octanes and 2-azabicyclo[3.2.2]nonanes were synthesized. Their activities were examined in vitro against the multiresistant K1 strain of Plasmodium falciparum and against Trypanosoma brucei rhodesiense (STIB 900). A couple of the newly synthesized compounds showed promising Antiprotozoal Activity and selectivity. The results of the biological tests of the novel compounds were compared with the activities of already synthesized compounds and of drugs in use. Structure-Activity relationships were discussed.
Thomas J. Schmidt – One of the best experts on this subject based on the ideXlab platform.
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Salvia Species as Sources of Natural Products with Antiprotozoal Activity
International Journal of Molecular Sciences, 2018Co-Authors: Núria Llurba-montesino, Thomas J. SchmidtAbstract:Natural products from plants have been used since ancestral times to treat a wide variety of diseases worldwide. Plants of the genus Salvia (Sage) have been reported to be used for the prevention and treatment of various diseases and ailments. In particular, some Salvia species have been used in traditional medicine to treat diseases caused by protozoan parasites of the genera Trypanosoma, Leishmania and Plasmodium and scientific studies have demonstrated the Activity of various isolated constituents from these plants against these pathogens. The current review attempts to give a critical overview of published information about the Antiprotozoal Activity of species of the genus Salvia and their chemical constituents. It is meant to give a unified overview of these results in order to avoid repetitions caused, e.g., by limited access to some primary reports, and to stimulate further research to possibly facilitate the development of new molecular leads against protozoal neglected tropical diseases (NTDs) based on Salvia constituents.
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Alkamides from Anacyclus pyrethrum L. and Their in Vitro Antiprotozoal Activity.
Molecules, 2017Co-Authors: J B Althaus, Marcel Kaiser, Reto Brun, Claudine Malyszek, Thomas J. SchmidtAbstract:In our ongoing study to evaluate the Antiprotozoal Activity of alkamides from Asteraceae, a dichloromethane extract from the roots of Anacyclus pyrethrum L. showed a moderate in vitro Activity against the NF54 strain of Plasmodium falciparum and against Leishmania donovani (amastigotes, MHOM/ET/67/L82 strain). Seven pure alkamides and a mixture of two further alkamides were isolated by column chromatography followed by preparative high performance liquid chromatography. The alkamides were identified by mass- and NMR-spectroscopic methods as tetradeca-2E,4E-dien-8,10-diynoic acid isobutylamide (anacycline, 1), deca-2E,4E-dienoic acid isobutylamide (pellitorine, 2), deca-2E,4E,9-trienoic acid isobutylamide (3), deca-2E,4E-dienoic acid 2-phenylethylamide (4), undeca-2E,4E-dien-8,10-diynoic acid isopentylamide (5), tetradeca-2E,4E,12Z-trien-8,10-diynoic acid isobutylamide (6), and dodeca-2E,4E-dien acid 4-hydroxy-2-phenylethylamide (7). Two compounds—undeca-2E,4E-dien-8,10-diynoic acid 2-phenylethylamide (8) and deca-2E,4E-dienoic acid 4-hydroxy-2-phenylethylamide (9)—were isolated as an inseparable mixture (1:4). Compounds 3, 4, and 5 were isolated from Anacyclus pyrethrum L. for the first time. While compounds 4 and 5 were previously known from the genus Achillea, compound 3 is a new natural product, to the best of our knowledge. All isolated alkamides were tested in vitro for Antiprotozoal Activity against Plasmodium falciparum, Trypanosoma brucei rhodesiense, Trypanosoma cruzi, and Leishmania donovani and for cytotoxicity against L6 rat skeletal myoblasts.
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Antiprotozoal Activity of achillea ptarmica asteraceae and its main alkamide constituents
Molecules, 2014Co-Authors: J B Althaus, Marcel Kaiser, Reto Brun, Thomas J. SchmidtAbstract:In the course of our ongoing screening of plants of the family Asteraceae for Antiprotozoal Activity, a CH2Cl2-extract from the flowering aerial parts of Achillea ptarmica L. (sneezewort yarrow) was found to be active in vitro against Trypanosoma brucei rhodesiense (IC50 = 0.67 µg/mL) and Plasmodium falciparum (IC50 = 6.6 μg/mL). Bioassay guided fractionation led to the isolation and identification of five alkamides from the most active fractions. Pellitorine and 8,9-Z-dehyropellitorine are the main components of the extract. Beside these olefinic acid amides, four alkamides with diene-diyne structures were isolated. All alkamides were tested for Antiprotozoal Activity in vitro. Pellitorine was the most active compound so far within this study against P. falciparum (IC50 = 3.3 µg/mL), while 8,9-Z-dehydropellitorine was most active against T. b. rhodesiense (IC50 = 2.0 µg/mL). The Activity of pure pellitorine against Plasmodium is higher than that of the crude extract and thus explains the Activity of the latter. None of the isolated alkamides, however, was as active against T. b. rhodesiense as the crude extract whose antitrypanosomal Activity must therfore be due to a synergistic effect of the isolated compounds or to more active yet to be identified constituents.
Marcel Kaiser – One of the best experts on this subject based on the ideXlab platform.
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Phototemtide A, a Cyclic Lipopeptide Heterologously Expressed from Photorhabdus temperata Meg1, Shows Selective Antiprotozoal Activity.
ChemBioChem, 2020Co-Authors: Lei Zhao, Marcel Kaiser, Helge B. BodeAbstract:A new cyclic lipopeptide, phototemtide A (1), was isolated from Escherichia coli expressing the biosynthetic gene cluster pttABC from Photorhabdus temperata Meg1. The structure of 1 was elucidated by HR-ESI-MS and NMR experiments. The absolute configurations of amino acids and 3-hydroxyoctanoic acid in 1 were determined by using the advanced Marfey’s method and comparison after total synthesis of 1, respectively. Additionally, three new minor derivatives, phototemtides B-D (2-4), were identified by detailed HPLC-MS analysis. Phototemtide A (1) showed weak Antiprotozoal Activity against Plasmodium falciparum, with an IC50 value of 9.8 μm. The biosynthesis of phototemtides A-D (1-4) was also proposed.
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Design, Synthesis, and Testing of Antiprotozoal Activity of Primin and Analogues
Journal of Medicinal and Chemical Sciences, 2019Co-Authors: Hamid R. Nasiri, Marcel Kaiser, Betül Ceylan, Katharina F. Hohmann, Harald SchwalbeAbstract:A set of conformationally restricted analogues of the natural product primin were synthesized as potential Antiprotozoal agents. The synthesis utilizes quinone C-H functionalization methods to enable an efficient and easy access to primin analogues. The Antiprotozoal activities of this series were evaluated in a panel of parasites and compared with the natural product primin. For all synthesized primin analogues a potent in vitro Activity was found against the pathogen Trypanosoma brucei rhodesiense (IC50 < 0.05 µg/mL). The observed Antiprotozoal Activity is not related to production of reactive oxygen species (ROS). Initial results of the in vivo experiments with a T. b. rhodesiense rodent animal model of the human disease were also reported. Intraperitoneal injection administration of compound 7 resulted in complete clearance of T. b. rhodesiense in tested rodent animals 24 hours after the last treatment. Our results show that the primin scaffold represents a new scaffold for further development of potent inhibitors of Trypanosoma brucei rhodesiense.
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Synthesis of Jacaranone-Derived Nitrogenous Cyclohexadienones and Their Antiproliferative and Antiprotozoal Activities.
Molecules, 2018Co-Authors: Armin Presser, Marcel Kaiser, Robert Saf, Gunda Lainer, Nadine Kretschmer, Wolfgang Schuehly, Marc Manuel KaltAbstract:The cytotoxic and Antiprotozoal activities of the phytoquinoide, jacaranone, and related compounds have been an ongoing topic in recent drug discovery. Starting from the natural product-derived cyclohexadienone scaffold, a series of nitrogen-containing derivatives were synthesized and subsequently evaluated for their antiproliferative and Antiprotozoal Activity. Anticancer potency was analyzed using different types of cancer cell lines: MDA-MB-231 breast cancer, CCRF-CEM leukemia, HCT-116 colon cancer, U251 glioblastoma, and, in addition, non-tumorigenic MRC-5 lung fibroblasts. Antiproliferative activities at micromolar concentrations could be shown. Antiprotozoal Activity was assessed against Plasmodium falciparum NF54 and Trypanosoma brucei rhodesiense STIB900. For all compounds, selectivity indices (SI) were calculated based on assessed cytotoxicity towards L6 cells. In addition, the structure-Activity-relationships and physicochemical parameters of these compounds are discussed.