Regioselective microwave synthesis and derivatization of 1,5-diaryl-3-amino-1,2,4-triazoles and a study of their cholinesterase inhibition properties

Herein we describe the development of an efficient one-pot regioselective synthesis protocol to obtain N-protected or N-deprotected 1,5-diaryl-3-amino-1,2,4-triazoles from N-acyl-N-Boc-carbamidothioates. This improved protocol using microwave irradiation and low reaction times (up to 1 h) furnished desired compounds in yields ranging from 50 to 84%. This chemistry is useful for a variety of aromatic groups with electronically diverse substituents. The design and correct derivation of the amino group led to compounds able to inhibit cholinesterases with good IC50 of up to 1 μM. Also, the mode of action (mixed-type) and SAR analysis for this series of compounds was described by means of kinetic and molecular modelling evaluations, showing potential for this class of compounds as new scaffolds for this biological activity.