Table of Contents
Preface ix
List of Abbreviations xi
1 Introduction 1
1.1 Steroids and Steroid Dimers 1
1.2 General Physical and Spectroscopic Properties of Steroid Dimers 2
1.3 Chromatographic Behaviour of Steroid Dimers 5
1.4 Applications of Steroid Dimers 6
References 6
2 Synthesis of Acyclic Steroid Dimers 7
2.1 Dimers via Ring A–Ring A Connection 7
2.1.1 Direct Connection 7
2.1.2 Through Spacer Groups 21
2.2 Dimers via Ring B–Ring B Connection 68
2.2.1 Direct Connection 68
2.2.2 Through Spacer Groups 74
2.3 Dimers via Ring C–Ring C Connection 84
2.3.1 Through Spacer Groups 84
2.4 Dimers via Ring D–Ring D Connection 87
2.4.1 Direct Connection 87
2.4.2 Through Spacer Groups 89
2.4.3 Through Side Chain and Spacer Groups 100
2.5 Dimers via Ring A–Ring D Connection 151
2.5.1 Direct Connection 151
2.6 Dimers via Connection of C-19 169
2.7 Molecular Umbrellas 170
2.8 Miscellaneous 174
References 182
3 Synthesis of Cyclic Steroid Dimers 187
3.1 With Spacer Groups: Cholaphanes 187
3.2 Without Spacer Groups: Cyclocholates 232
References 238
4 Naturally Occurring Steroid Dimers 241
4.1 Cephalostatins 242
4.2 Crellastatins 254
4.3 Ritterazines 262
4.4 Others 277
References 284
5 Synthesis of Cephalostatin and Ritterazine Analogues 287
5.1 Introduction 287
5.2 Synthesis of Cephalostatin and Ritterazine Analogues 288
5.3 Total Synthesis of Naturally Occurring Cephalostatin 1 371
References 376
6 Applications of Steroid Dimers 379
6.1 Application of Steroid Dimers as ‘Molecular Umbrellas’: Drug Delivery 379
6.2 Biological and Pharmacological Functions of Steroid Dimers: Drug Discovery and Design 382
6.2.1 Antimalarial Activity 383
6.2.2 Cytotoxicity and Anticancer Potential 386
6.2.3 Effect on Micellar Concentrations of Bile Salts and Serum Cholesterol Level 401
6.2.4 Effect on Bilayer Lipid Membranes 402
6.2.5 Supramolecular Transmembrane Ion Channels, and Artificial Receptors and Ionophores 402
6.2.6 Other Properties 404
References 405
Index 409