This fourth volume in the series Organic Synthesis: Theory and Applications is composed of five chapters that span a wide range of disciplines. Alkaloid chemistry, total synthesis, synthetic methodology, carbohydrate technology, and spin-trapping agents are all covered by experts in these fields. The first chapter is one of the finest examples of deductive reasoning in the chemical literature, examining the rich history of the chemistry of morphine. Within the following chapters, synthetic challenges of the marine terpenoids are brought into focus, the chemistry and synthetic applications of cyclobutenediones are reviewed and the utility of glycosyl iodides in the preparation of glycosides are summarized. Finally a report on a new class of spin-traping agents, azulenyl nitrones is covered. In all, five diverse subdisciplines are brought together and reviewed in this volume. Preface. The story of morphine structure elucidation: one hundred years of deductive reasoning. Synthesis of terpenoids of marine origin. Cyclobutenediones as versatile four-carbon synthons in organic synthesis. Glycosyl iodides in organic synthesis. Aspects of the chemistry and biology of azulenyl nitrones, a newly synthesized class of spin-trapping agents. Biographical sketches of the contributers.