Guanosine
Guanosine is a [purine] [nucleoside] which is made up of a guanine attached to a purine with a beta N9-glycosidic bond. It can be phosphorylated to form important [molecules] such as guanosine monophosphate ([GMP]), guanosine diphosphate ([GDP]) and guanosine triphosphate ([GTP]).