Abstract:
A facile, convenient and high yielding synthesis of a series of novel 5-(3′-indolyl)-2-(substituted)-1,3,4-oxadiazoles from readily available starting materials has been described. The key step of this protocol is oxidative cyclization of N-acylhydrazones 1 using [bis(trifluoroacetoxy)iodo]benzene under solvent-free condition. The 5-(3′-indolyl)-2-(substituted)-1,3,4-oxadiazoles were screened for their in vitro anticancer activity against various human cancer cell lines. Compounds 3c, 3d and 3j exhibited potent cytotoxicity (IC50 ∼1 μM) and selectivity against human cancer cell lines.