In addition to foundational concepts, the book provides case studies and detailed illustrations that guide readers through synthesizing N-, O-, and S-heterocycles, as well as total and semisynthesis of bioactive compounds. It covers sonochemical reactions under solvent- and catalyst-free conditions, the use of aqueous media as a green solvent, and the application of nanoparticles as catalysts. The book also addresses drug design, synthesis, and the intersection of ultrasound technology with pharmaceutical and environmental chemistry, offering practical methodologies and insights for both academic and industry audiences.