quinelike

Quinolike is an adjective used in chemistry and related fields to describe molecules that resemble quinoline in structure or properties. Quinoline is a heterocyclic aromatic compound formed by a benzene ring fused to a pyridine ring. Consequently, quinoline-like molecules typically possess a fused bicyclic framework in which a nitrogen-containing heteroaromatic ring is integrated with an additional ring, or they carry substituents that preserve the overall electronic and planar character of the quinoline core. The term can also apply to scaffolds that retain the characteristic pi system, basic nitrogen, and potential sites for substitution associated with quinoline.

In medicinal chemistry, quinoline and related quinoline-like scaffolds appear widely in natural products and drugs. They feature in antimalarial agents such as chloroquine and quinine derivatives, as well as various antibiotics, anticancer candidates, and other therapeutic leads. Quinoline-like motifs are also common in dyes, fluorescent probes, and organic electronic materials, where the planar, electron-rich character supports specific optical or electronic properties.

Usage and scope of the term are informal rather than strict systematic nomenclature. Quinoline-like descriptions are used to convey structural resemblance or related chemical behavior rather than to define a discrete, official class. The term should not be confused with quinone, which refers to a distinct non-aromatic oxygen-containing motif, or with quinolone, which denotes a different subclass of heterocycles. See also quinoline and isoquinoline for closely related cores.