Two decades of the synthesis of mono- and bis-aminomercapto[1,2,4]triazoles

Abstract

4-Amino-5-mercapto[1,2,4]triazole and its 3-substituted derivatives have proven to be of biological interest and provide access to a new class of biologically active heterocyclic compounds for biomedical applications. This study will be helpful for scientific researchers interested in the chemistry of bifunctional versatile compounds as it provides a collection of all the methods for the preparation of 3-substituted-4-amino-5-mercapto[1,2,4]triazoles with aliphatic, aromatic, and heterocyclic moieties during the period from 2000 to mid-2020.

Chart 1. Examples of [1,2,4]triazole bearing drugs.

Chart 2. Structures of bis-[4-amino-5-mercapto[1,2,4]triazoles] (1) and 3-substituted-4-amino-5-mercapto[1,2,4]triazoles (2–4).

Scheme 1. Synthesis of triazoles 2–4.

Scheme 2. Synthesis of bis-triazoles 8 and 9.

Scheme 3. Synthesis of bis-triazole 11.

Scheme 4. Synthesis of triazoles 13.

Scheme 5. Synthesis of bis-triazole 15.

Scheme 6. Synthesis of triazole 17.

Scheme 7. Synthesis of triazoles 21–23.

Scheme 8. Synthesis of triazoles 2 and 3.

Scheme 9. Synthesis of bis-triazole 27.

Scheme 10. Synthesis of bis-triazole 29.

Scheme 11. Synthesis of triazoles 4.

Scheme 12. Synthesis of bis-triazoles 34 and 35.

Scheme 13. Synthesis of bis-triazoles 38 and 39.

Scheme 14. Synthesis of bis-triazoles 42 and 43.

Scheme 15. Synthesis of triazoles 2–4.

Scheme 16. Synthesis of bis-triazole 45.

Scheme 17. Synthesis of bis-triazole 47.

Scheme 18. Synthesis of bis-triazole 49.