Synthesis of 6-R-3-(2-Aminophenyl)-2Н-1,2,4-Thriazin-5-ones: Resources and Limitations

Authors: 
Alexey Voskoboynik, Galina Berest, Dmitriy Skorina, Alexander Karpenko and Sergey Kovalenko

The novel methods of 6-R-3-(2-aminophenyl)-2Н-1,2,4-triazin-5-ones synthesis by 2-R-[(3H-quinazoline-4-yliden)hydrazono]--carboxylic acid esters hydrazinolysis and nucleophylic cleavage of 3-R-2H-[1,2,4]triazino[2,3-c]quinazoline-2-ones are worked out. It is shown that 2-R-[(3H-quinazoline-4-yliden)–hydrazono]--carboxylic acid esters under hydrazinolysis form (3Н-quinazoline-4-yliden)hydrazine or 6-R-3-(2-aminophenyl)-2Н-1,2,4-triazin-5-ones. The reaction direction depends on geometric isomerism of corresponding esters.

[1] Perevalov S., Burgart Ya., Saloutin V. and Chupakhin O.: Russ. Chem. Rev., 2001, 11, 921.
[2] Kovalenko S., Voskoboynik A., Karpenko A. et al.: Zh. Org. ta Pharm. Khimii, 2008, 21, 25.
[3] Karpenko O., Kovalenko S., Chekotylo O. and Shyshkyna S.: Heterocycles, 2007, 3, 619.
[4] Kovalenko S., Voskoboynik O. and Karpenko O.: Zh. Org. ta Pharm. Khimii, 2007, 4(20), 54.
[5] Vereschagina N., Postovskii I. and Mertsalov S.: Zh. Obshey Khimii, 1964, 5, 1689.
[6] Vereschagina N., Postovskii I. and Mertsalov S.: Khimiya Geterocyklicheskih Soyed., 1967, 6, 1096.
[7] Antipenko L., Karpenko A., Kovalenko S. et al.: Chem. Pharm. Bull, 2009, 6, 580.