Nucleotides

Example: adenosine links with a phosphate group forming the nucleotide called adenylic acid or adenosine-monophosphate (AMP).
Since at physiological pH the phosphate is ionized, it is also called adenylate.

Two or three consecutive phosphate groups can also join, giving rise, respectively, to:
adenosine-diphosphate (ADP).
adenosine-triphosphate (ATP).
ATP is specially important for being the "energy currency" of cells.

Nucleotides formed with ribose are called ribonucleotides and take part in RNA, while those formed with deoxyribose are called deoxyribonucleotides and take part in DNA.