Metallofoldamers – Supramolecular Architectures from Helicates to Biomimetics

Professor Dr. Markus Albrecht: Institut fur Organische Chemie, RWTH Aachen, Germany Professor Albrecht was born in 1964 and studied Chemistry in Wurzburg and Munster, spending time as a postdoctoral fellow in the laboratories of Professor Kenneth N. Raymond in Berkeley, and a habilitation at the Institute of Organic Chemistry of the University of Karlsruhe. Since 2002 he has been Professor of Organic Chemistry at the RWTH Aachen, where his main topics of investigation are the self-assembly, structure and property of helicates, and influencing peptide conformations by metal coordination. Dr. Galia Maayan: The Department of Chemistry, University of Florida, USA Dr Maayan was born in 1974 and studied Chemistry at Tel Aviv University and at The Weizmann Institute of Science, Israel. She is currently a postdoctoral research associate with Professor Michael D. Ward and Kent Kirshenbaum, in the Molecular Design Institute at New York University, investigating the interaction between biomimetic foldamers and metal ions.

List of Contributors xi Foreword xiii Preface xv 1 Metalloproteins and Metallopeptides Natural Metallofoldamers 1 Vasiliki Lykourinou and Li-June Ming 1.1 Introduction 1 1.2 Metalloproteins 2 1.3 Metallopeptides 12 1.4 Conclusion and Perspectives 28 Acknowledgements 30 References 30 2 Introduction to Unnatural Foldamers 51 Claudia Tomasini and Nicola Castellucci 2.1 General Definition of Foldamers 51 2.2 Biotic Foldamers 53 2.3 Abiotic Foldamers 70 2.4 Organization Induced by External Agents 72 2.5 Applications 78 2.6 Conclusions and Outlook 81 References 81 3 Self-Assembly Principles of Helicates 91 Josef Hamacek 3.1 Introduction 91 3.2 Thermodynamic Considerations in Self-Assembly 93 3.3 Cooperativity in Self-Assembly 100 3.4 Kinetic Aspects of Multicomponent Organization 104 3.5 Understanding Self-Assembly Processes 108 3.6 Secondary Structure and Stabilizing Interactions 118 3.7 Conclusions 118 References 120 4 Structural Aspects of Helicates 125 Martin Berg and Arne Lutzen 4.1 Introduction 125 4.2 Structural Dynamics 127 4.3 Template Effects 129 4.4 Sequence Selectivity 130 4.5 Self-Sorting Effects in Helicate Formation 135 4.6 Diastereoselectivity I Meso -Helicate versus Helicate Formation 138 4.7 Diastereoselectivity II Enantiomerically Pure Helicates from Chiral Ligands 139 4.8 Summary and Outlook 150 References 151 5 Helical Structures Featuring Thiolato Donors 159 F. Ekkehardt Hahn and Dennis Lewing 5.1 Introduction 159 5.2 Coordination Chemistry of Bis- and Tris(Benzene-o-Dithiolato) Ligands 162 5.3 Coordination Chemistry of Mixed Bis(Benzene-o-Dithiol)/Catechol Ligands 176 5.4 Subcomponent Self-Assembly Reactions 181 5.5 Summary and Outlook 186 References 186 6 Photophysical Properties and Applications of Lanthanoid Helicates 193 Jean-Claude G. Bunzli List of Acronyms and Abbreviations 193 6.1 Introduction 194 6.2 Homometallic Lanthanoid Helicates 197 6.3 Heterometallic d-f Helicates 223 6.4 Chiral Helicates 236 6.5 Extended Helical Structures 239 6.6 Perspectives 240 Acknowledgements 241 References 241 7 Design of Supramolecular Materials: Liquid-Crystalline Helicates 249 Raymond Ziessel 7.1 Introduction 249 7.2 Imino-Bipyridine and Imino-Phenanthroline Helicates 252 7.2.1 Liquid Crystals from Imino-Polypyridine Based Helicates 257 7.3 Conclusions 266 7.4 Outlook and Perspectives 267 Acknowledgements 268 References 268 8 Helicates, Peptide-Helicates and Metal-Assisted Stabilization of Peptide Microstructures 275 Markus Albrecht 8.1 Introduction 275 8.2 Selected Examples of Metal Peptide Conjugates 276 8.3 Helicates and Peptide-Helicates 279 8.4 Metal-Assisted Stabilization of Peptide Microstructures 288 8.5 Conclusion 298 References 300 9 Artificial DNA Directed toward Synthetic Metallofoldamers 303 Guido H. Clever and Mitsuhiko Shionoya 9.1 Introduction 303 9.2 The Quest for Alternative Base Pairing Systems 309 9.3 Design and Synthesis of Metal Base Pairs 311 9.4 Assembly and Analysis of Metal Base Pairs Inside the DNA Double Helix 315 9.5 Artificial DNA for Synthetic Metallofoldamers 318 9.6 Functions, Applications and Future Directions 324 References 327 10 Metal Complexes as Alternative Base Pairs or Triplets in Natural and Synthetic Nucleic Acid Structures 333 Arnie De Leon, Jing Kong, and Catalina Achim 10.1 Introduction 333 10.2 Brief Overview of Synthetic Analogues of DNA: PNA, LNA, UNA, and GNA 338 10.3 Metal-Containing, Ligand-Modified Nucleic Acid Duplexes 340 10.4 Duplexes Containing Multiple Metal Complexes 361 10.5 Metal-Containing, Ligand-Modified Nucleic Acid Triplexes 367 10.6 Summary and Outlook 367 Acknowledgement 369 Abbreviations 369 References 370 11 Interaction of Biomimetic Oligomers with Metal Ions 379 Galia Maayan 11.1 Introduction 380 11.2 Single-Stranded Oligomers in Which Metal Coordination Templates, or Templates and Nucleates the Formation of an Abiotic Helix 381 11.3 Folded Oligomers in Which Metal Coordination Nucleates the Formation of an Abiotic Single-Stranded Helix 384 11.4 Folded Oligomers in Which Metal Coordination Enhances Secondary Structure and Leads to Higher-Order Architectures 393 11.5 Concluding Remarks 402 References 402 12 Applications of Metallofoldamers 407 Yan Zhao 12.1 Introduction 407 12.2 Metallofoldamers in Molecular Recognition 409 12.3 Metallofoldamers as Sensors for Metal Ions 414 12.4 Metallofoldamers as Dynamic Materials 419 12.5 Conclusions and Outlook 429 References 430 Index 433