containing a hetero ring of at least seven ring members, e.g. zearalenone, macrolide aglycons

Full Title

Preparation of heterocyclic carbon compounds with only O, N, S, Se or Te as ring hetero atoms (C12P13/04 - C12P13/24 take precedence) > Oxygen as only ring hetero atoms > containing a hetero ring of at least seven ring members, e.g. zearalenone, macrolide aglycons