(n) :
(organic chemistry) Any of four isomeric tricyclic heterocycles, derivatives of which often have biological action, consisting of a pyridine ring fused with the five-membered ring of an indole.
(n) :
(organic chemistry) Any of four isomeric tricyclic heterocycles, derivatives of which often have biological action, consisting of a pyridine ring fused with the five-membered ring of an indole.