Adenosine is a purine nucleoside comprising a molecule of adenine attached to a ribose sugar molecule moiety via a β-N9-glycosidic bond. It plays an important role in energy transfer. It is an endogenous purine nucleoside that modulates physiological process wherein cellular signaling by adenosine occurs through four known adenosine receptor subtypes (A1, A2A, A2B, and A3) Adenosine is an anti-inflammatory agent at the A(2A) receptor. Cardioprotective effects may relate to activation of A1 adenosine receptors.
Thymidine is a nucleoside composed of deoxyribose (a pentose sugar) joined to the pyrimidine base thymine.Deoxythymidine can be phosphorylated with one, two or three phosphoric acid groups, creating respectively dTMP, dTDP or dTTP (deoxythymidine mono- di- or triphosphate.It exists in solid form as small white crystals or white crystalline powder.The stability of deoxythymidine under standard temperature and pressure (STP) is very high.Thymidine is listed as a chemical teratogen.