Arabian Journal of Chemistry (Jun 2024)
Oxamic acid thiohydrazides and hydrazones based on them as convenient starting compounds for the synthesis of S- and N-containing heterocyclic products. A mini-review
Abstract
The chemistry of hydrazones is currently undergoing intensive development. For example, thioacylhydrazones, which are synthesized most often from thiosemicarbazides, have become very popular in recent years owing to impressive results of their extensive testing in medicinal chemistry. Their antiviral, insecticidal, antisclerotic, antioxidant, and antiparasitic activities have been demonstrated; thioacylhydrazones showed promise for the development of drugs against COVID-19 and HIV. The ligands based on these compounds with soft donor nitrogen and sulfur atoms are widely used in the creation of complexes with various bioactivities, including strong anticancer properties. Since the replacement of the oxygen atom with a sulfur atom may increase the biological activity of the compound, the desire to expand the spectrum of pharmacological action or to change the type of activity induces understandable interest in thio analogues of acylhydrazones that are known to have high bioactivity. At the same time, there are publications indicating that oxamic acid thiohydrazides containing thioamide and thiohydrazide moieties, due to their polyfunctional nature, can be effectively used in the synthesis of a wide variety of compounds, including bioactive products. This review describes the synthetic and applied potential of poorly investigated oxamic acid thiohydrazides and hydrazones based on them. A considerable benefit of these oxamic acid derivatives is the presence of an additional carboxamide group, which is itself significant for biological processes and can also be easily modified, thus providing a wealth of combinations for the synthesis of new promising products. The review describes convenient methods for the preparation of oxamic acid derivatives of this type and demonstrates their large synthetic potential, which opens up the way to new thiohydrazone analogues and to various heterocyclic compounds, including new-generation antibacterial drugs targeting the secretory system of bacteria, thus suppressing the infectious process and eliminating the pathogen from the body without affecting the proliferation of bacteria.
