Adenine combines with the sugar ribose to form adenosine, which in turn can be bonded with from one to three phosphoric acid units, yielding the three nucleotides adenosine monophosphate , adenosine diphosphate, and adenosine triphosphate . These adenine derivatives perform important functions in cellular metabolism. Adenine is one of four nitrogenous bases utilized in the synthesis of nucleic acids . A modified form of adenosine monophosphate is thought to be a secondary messenger in the propagation of many hormonal stimuli. Adenine is an integral part of the structure of many coenzymes.