( Subject ( ( matter ( wherein ( ( ( a ( heterocyclic compound ) ) ( ( containing ( a ( nitrogen atom ) ) ) ( as ( a ( ring atom ) ) ) ) ) ( is ( employed ( as ( a reactant ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Subject)) (VP (NN matter) (SBAR (WHADVP (WRB wherein)) (S (NP (NP (DT a) (JJ heterocyclic) (NN compound)) (VP (VBG containing) (NP (DT a) (NN nitrogen) (NN atom)) (PP (IN as) (NP (DT a) (NN ring) (NN atom))))) (VP (VBZ is) (VP (VBN employed) (PP (IN as) (NP (DT a) (NN reactant)))))))) (. .)))
Subject matter wherein a heterocyclic compound containing a nitrogen atom as a ring atom is employed as a reactant.
(ROOT (S (NP (DT A) (JJ heterocyclic) (NN compound)) (VP (VBZ contains) (NP (NP (NNS atoms)) (PP (IN of) (NP (NP (QP (CD two) (CC or) (JJR more)) (JJ different) (NNS elements)) (PP (IN in) (NP (PRP$ its) (NN ring) (NN structure))))))) (. .)))