Cancer and AIDS are the major causes of global health issue causing death worldwide. During the past few decades, targeted therapy has emerged as an idealistic and challenging approach for the evolution of selective anti-cancer and anti-AIDS agents. Hence, an update or modification in current therapeutics is required to combat these serious diseases more efficiently. The large numbers of biologically active molecules that contain heterocyclic rings play important roles in the drug discovery process and the oxazine derivatives are in the development phase as potential new drugs. This book provides the comprehensive literature review on biological activities and synthesis of oxazine derivatives in Chapter I. The chapter II and III deals with synthesis and chracterization of novel 2-pyrimidinyl-2, 3-dihydro-1H-naphtho [1, 2-e][1,3] oxazine and 2-thiazolyl-2, 3-dihydro-1H-naphtho [1, 2-e][1,3] oxazine derivatives respectively. The chapter IV and V are on the in vitro antitubulin and anti-AIDS activity of synthesized derivatives and study of Structure-Activity Relationship which will be helpful for new researcher to learn the design and synthesis of drug molecule.