A chemical having the general formula R1R2C=NR3, where R3 is an alkyl or an aryl but not a hydrogen, is referred to as an organic compound and is known as a Schiff base. They are a subclass of imines and, depending on their structural makeup, are either secondary ketimines or secondary aldimines. Aziomethine, which particularly refers to secondary aldimines (i.e., RCH=NR' where R' H), is frequently used as a synonym for the phrase. For these compounds, there are several unique naming schemes. In contrast, bis-compounds are sometimes referred to as salen-type compounds. As an example, a Schiff base generated from an aniline, where R3 is a phenyl or a modified phenyl, can be called an anil. When these chemicals are utilised as ligands to create coordination complexes with metal ions, the name "Schiff base" is typically used to describe them.