Explanation of terms used by DrugBank

Chemical Formula

Every natural or synthetic chemical substance is composed of a particular numerical proportion of atoms of specific elements grouped together. The chemical formula of such a substance is subsequently a written line of letters and numbers that typically represent the number of each type of elemental atom (ie. H for the hydrogen element) or functional groups (ie. OH for the hydroxy group) that makes up a single molecule of the substance or drug. In particular, this kind of molecular formula of a substance is a type of chemical formula that lists the exact number of each type of atom that makes up a molecule of the substance.

For example, the chemical formula for magnesium hydroxide is Mg(OH)2 - that is, one molecule of magnesium hydroxide is comprised of one atom of magnesium and two hydroxy groups.