Biological relevance and synthesis of C-substituted morpholine derivatives

C-Functionalized morpholines are found in a variety of natural products and biologically active compounds, but have also for other reasons been applied in organic synthesis. This review deals with the biological relevance of C-substituted morpholines, their synthesis and important applications in other syntheses. 1 Introduction 2 Biological Relevance of Morpholines 2.1 Naturally Occurring Morpholines 2.2 Bioactive Morpholines 2.2.1 Antidepressants 2.2.2 Appetite Suppressants 2.2.3 Antitumor Activity 2.2.4 Antioxidants 2.2.5 Miscellaneous 3 Morpholine Synthesis 3.1 Synthesis from Amino Alcohols 3.2 Synthesis from Epoxides 3.3 Synthesis via Organometallic Reactions 3.4 Synthesis from Olefins 3.5 Synthesis from Carboxylic Acid Derivatives 3.6 Miscellaneous 4 Morpholines as Synthetic Tools 4.1 The Williams Chiral Auxiliary 4.2 Chiral Auxiliaries 5 Conclusions.