Term Name:	precorrin
Synonyms:	precorrins
Definition:	Any of the intermediates in the biosynthesis of vitamin B12 from uroporphyrinogen III that lie on the pathway before the formation of the first corrin macrocycle. The figure after 'precorrin' corresponds to the number of C-methyl groups introduced into the tetrapyrrole framework.
Ontology:	ChEBI [CHEBI:26228]  ( EBI )