Which of the following is a heterocyclic amine?
A heterocyclic compound or ring structure is a cyclic
compound that has atoms of at least two different elements as members of its
ring(s). Heterocyclic amines, also sometime referred to as HCAs, are chemical
compounds containing at least one heterocyclic ring, which by definition has
atoms of at least two different elements, as well as at least one amine
(nitrogen-containing) group.
Attached image is of piperidine, a heterocyclic amine by definition.