This book deals with discovery and development of drugs for treating variety of diseases. The present edition of Medicinal Chemistry treats many aspects of drugs such as Structure-Activity Relationships, Mechanism of action, synthetic concepts and clinical uses. Synthetic procedures are described in mechanistic approach in simple language. It provides comprehensive chemistry of synthetic drugs. In this book each chapter commences with an introduction followed by classification of drugs, Chemical names, structures and / or synthetic procedures, properties and uses of drugs.