Pyrimidine nucleosides provide versatile and novel building blocks for pharmacological targets. They display fundamental and comprehensive roles in the growing area of medicinal chemistry. Various strategies for the synthesis of the many recent pyrimidine nucleosides have been exhibited throughout this book to access novel and potent pharmacological agents. Many of the synthesized pyrimidine nucleosides are considered as potential chemotherapeutic agents which offer a great impact on the current medicinal research. Recently, a number of pyrimidine S-glycosides, a new non classical class of nucleoside analogs, were synthesized by us and have been proved to be potential anticancer agents against many cell lines. The new insights for the current research of the pyrimidine nucleosides have offered significant opportunities for developing their synthetic approaches, that emulate our prospect in this book to be beneficial and valuable source to all scientists for drug discovery and developments.