Recent Advances in the Multicomponent Synthesis of Heterocycles Using 5-Aminotetrazole

Abstract

The unique reactivity and beneficial features of the 5-aminotetrazole synthon (1H-tetrazol-5-amine) have made it a versatile and effective building block in the synthesis of heterocyclic compounds. In addition, several drugs containing this scaffold with a wide array of biological properties have been already introduced. Heterocyclic structures are the backbone of many biologically active and industrially important compounds. 5-Aminotetrazole is one of the favored synthons used in the preparation of heterocycle-bearing compounds, especially in multicomponent synthesis. This review highlights a comprehensive overview of the emerging applications of 5-aminotetrazole as a key component in the synthesis of heterocyclic frameworks through multicomponent reactions, reported between 2017 and July 2023.1 Introduction2 5-Aminotetrazole3 Tetrazolopyrimidine Compounds4 Spiro Compounds5 Miscellaneous6 Conclusion

Recent advances in microwave-assisted multicomponent synthesis of spiro heterocycles

“…Single-crystal X-ray analyses of the pyrrolidine-fused bis-spirooxindoles unambiguously conrmed their structures and stereochemistries. 182 Mukhopadhyay et al reported a rapid method for the one-pot, chromatography-free synthesis of diversied dihydrospiro [indeno[1,2-b]pyridine]-4,3 0 -indolines (35) or the analogous spiro acenaphthylene-1,4 0 -indeno[1,2-b]pyridines (36). A viable microwave-assisted MCR in minimal aqueous ethanol (1 : 1, v/v) as the green solvent without any metal catalyst was demonstrated by using a mixture of a series of substituted amines (33) and isatins (1) or acenaphthenequinone (1 0 ), malononitrile (17) or acyclic-1,3-diketone (10), and indane-1,3-dione (34) (Scheme 11).…”

“…In addition to their rich chemical reactivity and ability to adopt various conformations, spiro heterocycles possess an array of intriguing biological functions due to their unique structural arrangements. [35][36][37][38][39][40] In this review, we report on the recent progress in MCRs 41-46 and summarize a comprehensive overview of the recent advances in the microwave-assisted MCR of spiro heterocycles, highlighting key developments and methodologies that have contributed to the rapid expansion of the technique applied the synthesis of spiro heterocycles. In addition to providing some perspectives for future research, we also outline the benets of this method and some challenges it faces.…”

“…In addition to their rich chemical reactivity and ability to adopt various conformations, spiro heterocycles possess an array of intriguing biological functions due to their unique structural arrangements. 35–40 …”

Recent developments using malononitrile in ultrasound-assisted multicomponent synthesis of heterocycles

“…Harnessing this approach, researchers have adeptly accessed an expansive class of biologically active molecules, encompassing pharmaceuticals, agrochemicals, and materials. These substances have promising uses in drug discovery and development since they display a diverse range of pharmacological activities, thus enhancing the synthesis of different heterocyclic frameworks [26] , [27] .…”