0000000000453825

AUTHOR

Frank Totzke

0000-0002-7261-8155

showing 4 related works from this author

Arthrinins A–D: Novel diterpenoids and further constituents from the sponge derived fungus Arthrinium sp.

2011

Bioassay-guided fractionation of a methanolic extract of the fungus Arthrinium sp., isolated from the Mediterranean sponge Geodia cydonium, afforded 10 natural products including five new diterpenoids, arthrinins A-D (1-4) and myrocin D (5). In addition, five known compounds were obtained, which included myrocin A (6), norlichexanthone (7), anomalin A (8), decarboxycitrinone (9) and 2,5-dimethyl-7-hydroxychromone (10). The structures of all isolated compounds were unambiguously elucidated based on extensive 1D and 2D NMR and HR-MS analyzes. The absolute configuration of arthrinins A-D (1-4) was established by the convenient Mosher method performed in NMR tubes and by interpretation of the R…

Vascular Endothelial Growth Factor AClinical BiochemistryPharmaceutical ScienceAntineoplastic AgentsBiochemistryMiceAscomycotaCell Line TumorNeoplasmsDrug DiscoveryAnimalsHumansMTT assayCytotoxicityProtein Kinase InhibitorsMolecular BiologyNeovascularization PathologicKinaseChemistryOrganic ChemistryTerpenoidIn vitroPoriferaEndothelial stem cellVascular endothelial growth factor ABiochemistryCell cultureMolecular MedicineDiterpenesProtein KinasesBioorganic & Medicinal Chemistry
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Profile and molecular modeling of 3-(indole-3-yl)-4-(3,4,5-trimethoxyphenyl)-1 H-pyrrole-2,5-dione (1) as a highly selective VEGF-R2/3 inhibitor.

2006

We report on selectivity profiling of 1 in a panel of 20 protein kinases and molecular modeling indicating 1 to be highly active and selective for VEGF-R2/3. Sequence alignment analysis and detailed insights into the ATP binding pockets of targeted protein kinases from the panel result in a unique structural architecture of VEGF-R2 mainly caused by the hydrophobic pocket I, determining the molecular basis for activity and selectivity of 1.

Indole testModels MolecularBinding SitesIndolesMolecular modelStereochemistryChemistryKinaseMolecular Sequence DataBiological activitySequence alignmentCrystallography X-RayVascular Endothelial Growth Factor Receptor-3Vascular Endothelial Growth Factor Receptor-2Drug DiscoveryMolecular MedicinePyrrolesAmino Acid SequenceBinding siteSelectivityPeptide sequenceHydrophobic and Hydrophilic InteractionsJournal of medicinal chemistry
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Bioactive pyrrole alkaloids isolated from the Red Sea : marine sponge Stylissa carteri

2017

Abstract Fifteen pyrrole alkaloids were isolated from the Red Sea marine sponge Stylissa carteri and investigated for their biological activities. Four of them were dibrominated [(+) dibromophakelline, Z-3-bromohymenialdisine, (±) ageliferin and 3,4-dibromo-1H-pyrrole-2-carbamide], nine compounds were monobrominated [(−) clathramide C, agelongine, (+) manzacidin A, (−) 3-bromomanzacidin D, Z-spongiacidin D, Z-hymenialdisine, 2-debromostevensine, 2-bromoaldisine and 4-bromo-1H-pyrrole-2-carbamide)] and finally, two compounds were non-brominated derivatives viz., E-debromohymenialdisine and aldisine. The structure elucidations of isolated compounds were based on 1D & 2D NMR spectroscopic …

StereochemistryCell Survival01 natural sciencesGeneral Biochemistry Genetics and Molecular BiologyCell LineRSchemistry.chemical_compoundAlkaloidsAnimalsHumansPyrrolesProtein kinase ACytotoxicityIndian OceanAgeliferinPyrrolebiologyMolecular Structure010405 organic chemistryKinasebiology.organism_classificationHCT116 Cells0104 chemical sciencesPorifera010404 medicinal & biomolecular chemistrySpongechemistryStylissa carteriDrug Screening Assays AntitumorTwo-dimensional nuclear magnetic resonance spectroscopy
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Design, Synthesis, and Biological Evaluation of 3,4-Diarylmaleimides as Angiogenesis Inhibitors

2006

The new analogue 2 of combretastatin A-4 was discovered to be an inhibitor of tubulin polymerization with an IC50 of 7.6 microM and reduced angiogenesis in the in vivo chick embryo model. Interestingly, in a series of 2,3-diarylmaleimides closely related to this lead, no other compound was found to be active in the tubulin polymerization assay. However, by screening in the in vivo chick embryo assay 10 was identified as a potent angiogenesis inhibitor indicating an alternative target. Indeed, molecular modeling studies suggest a reasonable binding mode of 10 at the ATP-binding site of the model kinase CDK2. Motivated by these results, analogues of 10 were screened for inhibitory activity in…

Models MolecularIndolesanimal structuresAngiogenesisAngiogenesis InhibitorsChick EmbryoIn Vitro TechniquesMaleimidesStructure-Activity Relationshipchemistry.chemical_compoundAdenosine TriphosphateIn vivoDrug DiscoveryAnimalsStructure–activity relationshipPyrrolesBinding siteCombretastatinBinding SitesbiologyChemistryKinaseCyclin-dependent kinase 2Vascular Endothelial Growth Factor Receptor-2Angiogenesis inhibitorBiochemistryDrug Designbiology.proteinMolecular MedicineJournal of Medicinal Chemistry
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