# OEIsMacrocycle¶

bool OEIsMacrocycle(const OEChem::OEMolBase &mol, const unsigned int minSize = 10)


Checks if the specified molecule is a macrocycle. The second argument refers to the minimum number of atoms required to be in a ring for the molecule to be treated as a macrocycle molecule. By default a molecule is defined as macrocycle when it contains a 10-membered or larger ring regardless of their aromaticity and hetero atoms content, so for example large cyclic alkanes, annulenes, crown ethers or porphyrins are all macrocycles.