We are delighted to present Medicinal Chemistry III – Theory, a textbook carefully developed to meet the academic requirements of pharmacy students and to provide a comprehensive understanding of medicinal chemistry. This book has been designed in accordance with the current syllabus and emphasizes the relationship between the chemical structure of drugs and their biological activity.

Medicinal Chemistry plays a crucial role in understanding drug design, development, mechanism of action, structure–activity relationships (SAR), metabolism, and therapeutic applications. The subject serves as a bridge between pharmaceutical chemistry and pharmacology, enabling students to appreciate how chemical modifications influence drug efficacy, safety, and selectivity. In this volume, various classes of therapeutic agents have been discussed systematically, including central nervous system drugs, anti-infective agents, antineoplastic agents, endocrine drugs, and other important medicinal compounds.

Special care has been taken to present the material in a clear, concise, and student-friendly manner. Illustrations, reaction schemes, tables, and review questions have been incorporated to enhance understanding and facilitate examination preparation.

We sincerely hope that this book will be a valuable resource for students, teachers, researchers, and pharmacy professionals. We welcome constructive suggestions and feedback for the improvement of future editions.