Oxindole (Indolin-2-one) is an aromatic heterocyclic building block. 2-indolinone derivatives have become lead compounds in the research of kinase inhibitors.

Oxindole (Indolin-2-one) is a bicyclic structure consisting of a benzene ring fused to 2-pyrrolidone. Substituted indolinones can be referred as 'privileged structures' owing to their excellent binding affinity for many receptors and to the number of approved drugs containing this scaffold[1]. Oxindole has been found in tissues and fluids of mammals as well as natural products produced by a range of plants, bacteria and invertebrates. 2-indolinone derivatives possess diverse range of pharmacological activities including anti-cancer, anti-HIV, anti-diabetic, antibacterial, antioxidant, kinase inhibitory, AChE inhibitory, anti-leishmanial, b3 adrenergic receptor agonistic, phosphatase inhibitory, analgesic, spermicidal, vasopressin antagonists, progesterone antagonists, neuroprotection, NMDA blocker and sleep inducing activities[2].

[1]. Leoni A, et al. 2-Indolinone a versatile scaffold for treatment of cancer: a patent review (2008-2014). Expert Opin Ther Pat. 2016;26(2):149-73. [2]. Kaur M, et al. Oxindole: A chemical prism carrying plethora of therapeutic benefits. Eur J Med Chem. 2016 Nov 10;123:858-894.