《Parallel synthesis of derivatives of 1H-1,2,4-triazole-3-carboxylic acids with heterocyclic substituents at position 5》 was written by Grebenkina, Lyubov E.; Matveev, Andrey V.; Chudinov, Mikhail V.. Product Details of 16982-21-1 And the article was included in Chemistry of Heterocyclic Compounds (New York, NY, United States) in 2020. The article conveys some information:
A mild universal method for the synthesis of derivatives of 5-substituted 1H-1,2,4-triazole-3-carboxylic acids I (R = tetrahydrofuran-2-yl, furan-3-yl, tetrahydropyran-2-yl, thiophen-3-yl, pyridin-2-yl, etc.; R1 = OEt, NH2) from a single precursor, Et β-N-Boc-oxalamidrazone, has been proposed. The method was applied for the parallel synthesis of a library of 1H-1,2,4-triazole-3-carboxamides I (R1 = NH2) with heterocyclic substituents at position 5. After reading the article, we found that the author used Ethyl 2-amino-2-thioxoacetate(cas: 16982-21-1Product Details of 16982-21-1)
Ethyl 2-amino-2-thioxoacetate(cas: 16982-21-1) belongs to anime. Primary amines having a tertiary alkyl group (R3CNH2) are difficult to prepare with most methods but are made industrially by the Ritter reaction. In this method a tertiary alcohol reacts with hydrogen cyanide (HCN) in the presence of a concentrated strong acid; a formamide, RNH―CHO, is formed first, which then undergoes hydrolysis.Product Details of 16982-21-1
Referemce:
Ester – Wikipedia,
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