Which of the following is not a fused-ring heterocycle?

A) purine
B) pyrimidine
C) benzofuran
D) indole
E) quinoline

Fused-ring Heterocycle

A cyclic compound where two or more rings share two or more common atoms, with at least one of the rings containing atoms other than carbon.

Purine

A heterocyclic aromatic organic compound, forming the basis of two of the four nucleotides that constitute DNA and RNA (adenine and guanine).

Pyrimidine

A heterocyclic aromatic organic compound, similar to benzene and pyridine, containing nitrogen atoms at positions 1 and 3 in the ring.