Hydrazonoyl Halides as Precursors for Synthesis of Bioactive Heterocyclic Compounds via Reaction with Aryl- and Hetaryl-Amine

A literature survey revealed that a great deal of interest had been focused on the synthesis of functionalized heterocyclic compounds due to their wide range of biological activities such as antimicrobial, antitumor, anti-inflammatory, antiviral, antibiotic, antidepressant, antimalarial, antifungal and antihypertensive. Moreover, it is used as pharmaceuticals, agrochemicals and veterinary products. They are also found in sensitizers, developers, antioxidants, as corrosion inhibitors, as copolymers, and dyes. On the other hand, hydrazonoyl halides are interesting synthons for valuable bioactive heterocyclic compounds. Reaction of hydrazonoyl halides with various types of aryl-amines and hetaryl-amines generated a huge number of different heterocyclic systems. In this review, we collected all reactions of hydrazonoyl halides with aryl- and hetaryl amines and classified them according to the type of the amines up to the end of 2021. Most reaction types have been successfully applied and used in the production of biologically active compounds.