Publications de Wee Han Ang | EPFL Graph Search

A structure-based mechanism of cisplatin resistance mediated by glutathione transferase P1-1

Paul Joseph Dyson, Wee Han Ang, Laure Menin

Cisplatin [cis-diamminedichloroplatinum(II) (cis-DDP)] is one of the most successful anticancer agents effective against a wide range of solid tumors. However, its use is restricted by side effects and/or by intrinsic or acquired drug resistance. Here, we ...

National Academy of Sciences2019

Development of an Efficient Dual-Action GST-Inhibiting Anticancer Platinum(IV) Prodrug

Paul Joseph Dyson, Wee Han Ang, Patrycja Nowak-Sliwinska

The cytotoxicity of cisplatin (cDDP) is enhanced when co-administered with ethacrynic acid (EA), a glutathione S-transferase (GST) inhibito r. A Pt-lV EA conjugate containing a cDDP core and two axial ethacrynate ligands (compound 1) was shown to be an ex ...

2018

Ligand substitutions between ruthenium-cymene compounds can control protein versus DNA targeting and anticancer activity

Paul Joseph Dyson, Ursula Röthlisberger, Wee Han Ang, Pablo Campomanes Ramos, Alexey Nazarov, Michael Groessl, Catherine Marie Amélie Clavel

Ruthenium compounds have become promising alternatives to platinum drugs by displaying specific activities against different cancers and favourable toxicity and clearance properties. Nonetheless, their molecular targeting and mechanism of action are poorly ...

Nature Research2014

Phosphorylation of Diaminopyridines: Synthesis of a Compound Containing Both a Diphosphinoamine ( P-N-P) and an Iminobiphosphine ( N=P-P) Fragment

Rosario Scopelliti, Paul Joseph Dyson, Zhaofu Fei, Wee Han Ang, Emilia Paunescu

The phosphorylation of a series of diaminopyridines (2,3-, 3,4-, 2,5- and 2,6-diaminopyridine), with various molecular equivalents of chlorodiphenylphosphine in the presence of TEA has been studied. Notably, phosphorylation of 2,3- and 3,4-diaminopyridine ...

Wiley-V C H Verlag Gmbh2014

Anthracene-Tethered Ruthenium(II) Arene Complexes as Tools To Visualize the Cellular Localization of Putative Organometallic Anticancer Compounds

Rosario Scopelliti, Paul Joseph Dyson, Wee Han Ang, Julie Risse, Christian Hartinger, Alexey Nazarov, Michael Groessl, Olivier Pierre Zava, Albert Ruggi, Frédéric Schmitt

Anthracene derivatives of ruthenium(II) arene compounds with 1,3,5-triaza-7-phosphatricyclo[3.3.1.1]decane (pta) or a sugar phosphite ligand, viz., 3,5,6-bicyclophosphite1,2-O-isopropylidene-alpha-D-glucofuranoside, were prepared in order to evaluate their ...

2012

Acetal-Functionalized RAPTA Complexes for Conjugation and Labeling

Paul Joseph Dyson, Wee Han Ang

Ruthenium-arene complexes bearing the 1,3,5-triaza-7-phosphatricyclo-[3.3.1.1]decane ligand, namely, RAPTA compounds, are widely investigated as potential antimetastatic agents for cancer therapy. Although much evidence points toward covalent binding with ...

American Chemical Society2011

Characterization of New Potential Anticancer Drugs Designed To Overcome Glutathione Transferase Mediated Resistance

Paul Joseph Dyson, Wee Han Ang, Jie Zhang

Resistance against anticancer drugs remains a serious obstacle in cancer treatment. Here we used novel strategies to target microsomal glutathione transferase 1 (MGST1) and glutathione transferase pi (GSTP) that are often overexpressed in tumors and confer ...

2011

Studies of Glutathione Transferase P1-1 Bound to a Platinum(IV)-Based Anticancer Compound Reveal the Molecular Basis of Its Activation

Paul Joseph Dyson, Ursula Röthlisberger, Wee Han Ang, Pablo Campomanes Ramos

Platinum-based cancer drugs, such as cisplatin, are highly effective chemotherapeutic agents used extensively for the treatment of solid tumors. However, their effectiveness is limited by drug resistance, which, in some cancers, has been associated with an ...

Wiley-Blackwell2011

An Internal Fluorescent Probe Based on Anthracene to Evaluate Cation-Anion Interactions in Imidazolium Salts

Rosario Scopelliti, Paul Joseph Dyson, Zhaofu Fei, Wee Han Ang, Christian Hartinger, Xuemei Yang

A series of fluorescent imidazolium-based salts contg. the cation [AnCH2MeIm]+ (in which An=anthracene and Im=the imidazolium cation) with Cl-, BF4-, PF6-, SO3CF3-, [N(CN)2]-, [N(SO2CF3)2]-, or PhBF3- anions have been prepd. and characterized. X-ray diffra ...

2010

Organometallic complexes that interconvert between trimeric and monomeric structures as a function of pH and their effect on human cancer and fibroblast cells

Kay Severin, Rosario Scopelliti, Paul Joseph Dyson, Zacharias Immanuel Grote, Wee Han Ang

Organometallic half-sandwich complexes based on ruthenium with aminomethyl-substituted 3-hydroxy-2-pyridone ligands exist in aqueous solution as monomeric O,O′-chelate complexes or trimeric metallamacrocycles depending upon the pH. We hypothesized that adm ...

2009

A Crystallographic Story of Snakes and Ladders: Encapsulated Water Polymers and Rigid Metal Complexes Based on Mono-N-substituted Carboxylate 4,4'-Bipyridine

Rosario Scopelliti, Paul Joseph Dyson, Zhaofu Fei, Wee Han Ang, Andrew Douglas Phillips

A new zwitterionic bidentate ligand was synthesized incorporating a 4,4'-bipyridine core with a carboxylate group as a single building block, specifically designed for the rational construction of supramol. structures (metal-org. frameworks) that are capab ...

2009

Trimetal-arene clusters with anticancer activity

Paul Joseph Dyson, Wee Han Ang

The invention relates to new medicaments, pharmaceutical compns. and methods of treatment of cancer. The invention discloses trimetallic clusters for use as a medicament, in particular in the treatment of cancer including metastasis. Preferably, the compds ...

2009

Rational Design of an Organometallic Glutathione Transferase Inhibitor

Paul Joseph Dyson, Wee Han Ang

Double trouble: A hybrid org.-inorg. (organometallic) inhibitor was designed to target glutathione transferases. The metal center is used to direct protein binding, while the org. moiety acts as the active-site inhibitor (see picture). The mechanism of inh ...

Wiley-VCH Verlag GmbH2009

Ferrocenoyl Pyridine Arene Ruthenium Complexes with Anticancer Properties: Synthesis, Structure, Electrochemistry, and Cytotoxicity

Paul Joseph Dyson, Wee Han Ang

Reaction of the dimers [Ru(h6-arene)Cl2]2 (arene = C6H6, C6H5Me, p-iPrC6H4Me, C6Me6) with 2 equiv of the ferrocenoyl pyridine (NC5H4(OOCC5H4FeC5H5)-4) affords Ru(II) complexes [Ru(h6-arene)Cl2(NC5H4OOCC5H4FeC5H5)] (arene = C6H6 (1, 85% yield), C6H5Me (2, 8 ...

2008

Palladium nanoparticles stabilized by an ionic polymer and ionic liquid: A versatile system for C-C cross-coupling reactions

Paul Joseph Dyson, Dongbin Zhao, Zhaofu Fei, Wee Han Ang, Yuehui Li, Xuemei Yang

Highly stable palladium nanoparticles 5 nm diam., protected by an imidazolium-based ionic polymer in a nitrile-functionalized ionic liq., have been prepd. and characterized by TEM. These Pd nanoparticles are excellent precatalysts for Suzuki, Heck, and Sti ...

2008

Synthesis of new aminophosphine complexes and their catalytic activities in C-C coupling reactions

Rosario Scopelliti, Zhaofu Fei, Wee Han Ang

Two new aminophosphines, benzyl-N(Ph2P)(2) and 2-picolyl-N(Ph2P)(2), have been synthesized. Oxidation of the aminophosphines with either hydrogen peroxide, elemental sulfur and selenium gave the corresponding oxides, sulfides and selenides benzyl-N(Ph2P=E) ...

2008

Synthesis and characterizations of N,N-bis(diphenylphosphino)ethylaniline derivatives and X-ray crystal structure of palladium (II), platinum (II) complexes

Rosario Scopelliti, Zhaofu Fei, Wee Han Ang

N,N-Bis(diphenylphosphino)ethylaniline compounds, Ph2PN-C6H4-C2H5, with ethyl groups at the ortho- and para-positions have been synthesized. Oxidation of the aminophosphines with hydrogen peroxide, elemental sulfur and selenium gave the corresponding ...

2008

Aminophosphine complex as a catalyst precursor in Suzuki coupling reactions

Dongbin Zhao, Zhaofu Fei, Wee Han Ang

A palladium complex with an aminophosphine ligand has been prepared and investigated as a catalyst precursor in Suzuki coupling reactions in toluene. Nanoparticles composed of elemental palladium have been isolated from the reaction media and analyzed usin ...

2008

Ruthenium Porphyrin Compounds for Photodynamic Therapy of Cancer

Paul Joseph Dyson, Wee Han Ang, Frédéric Schmitt

Five 5,10,15,20-tetra(4-pyridyl)porphyrin (TPP) areneruthenium(II) derivs., a p-cymeneosmium, a pentamethylcyclopentadienyliridium and a pentamethylcyclopentadienylrhodium analog were prepd. and characterized as potential photosensitizing chemotherapeutic ...

2008

Transition metal complexes for inhibiting resistance in the treatment of cancer and metastasis

Paul Joseph Dyson, Wee Han Ang

The present invention relates to organometallic compounds useful in the treatment of metastasis. The organometallic compounds comprise a ligand that is convalently bound to a bioactive compound, which is an inhibitor of a resistance pathway or a derivative ...

2007