Azole

An azole is a type of organic compound. Azoles have a pentagon-shaped ring of five atoms. Azoles have two double bonds, like cyclopentadiene, and have at least one nitrogen atom.

Azole is the systematic name of pyrrole, the simplest azole. Its analogs are called pyrroles. Other azoles can have a second heteroatom, which can be chalcogen (oxygen, sulfur, selenium, or tellurium) or more nitrogen.

Types

Azoles are grouped by the type of heteroatom in the ring.

Type	Second heteroatom	Example	Example structure
Pyrroles	None	Pyrrole
Oxazoles	Oxygen	Oxazole
		Isoxazole
Thiazoles	Sulfur	Thiazole
		Isothiazole
Imidazoles	Nitrogen	Imidazole
		Pyrazole

There are also selenazoles and tellurazoles, containing selenium and tellurium. These molecules are much less common and do not have notable applications.

Sources