Adenosine is a kind of nucleoside. It consists of respectively part of ribose (ribofuranose) and adenine; middle of these two parts is connected withβ-N9-and matched sugar linkage (β-N9-glycosidic bond). Adenosine is a kind of endogenous nucleoside that widely distributed in human body. It can directly enter into the cardiac muscle, and generate adenylate through phosphorylation, participate in myocardial energy metabolism and simultaneously participate in expending coronary bypass and adding blood flow volume. Adenosine I has physiological action with cardiovascular system and other system and tissues of human body. Adenosine is an important intermediate used to compound triphosadenine (ATP), adenine, adenylate and vidarabine.