A series of novel quinoline appended biaryls have been synthesized (5a−5o) by reacting various substituted boronic acids (4e−4h) with various substituted 2-(4-bromophenoxy)quinolin-3-carbaldehydes (3a−3d) through carbon−carbon bond formation. Effects of various quinoline appended biaryls (5a−5o) on the breast cancer protein 3ERT are moderate to high, as found by in silico molecular docking studies. Comparatively, all quinoline appended biaryls (5a−5o) 5h show better efficacy with a binding energy of −9.39 kcal/mol, and hydrogen bonds are Thr347, Glu353, and Arg394 in the binding pocket. Conclusively, the final novel quinoline appended biaryls (5a−5o) have been confirmed with all the spectral studies, and their efficacy has been validated with in silico studies.