Pyrrole

In organic chemistry, a pyrrole is a five membered aromatic ring, 4 elements of which are carbon atoms, one element of which is a nitrogen atom. The molecular formula for a pyrrole is C₄NH₅. The structure is:

Pyrroles are components of larger aromatic rings, including the porphyrins of heme, the chlorins and bacteriochlorins of chlorophyll, and the corrin ring of vitamin B12.