Synthesis of substituted 3-(5-amino-[1,3,4]thiadiazol-2-yl)-2H-pyrano[2,3-c]pyridin-2-ones

✍ Scribed by Irina O. Zhuravel'; Valentin P. Chernykh; Pavlo E. Shinkarenko; Sergiy M. Kovalenko; Alexandre V. Ivachtchenko

• Publisher: Journal of Heterocyclic Chemistry
• Year: 2004
• Tongue: English
• Weight: 222 KB
• Volume: 41
• Category: Article
• ISSN: 0022-152X
• DOI: 10.1002/jhet.5570410407

✦ Synopsis

Abstract

An efficient two‐step synthesis of novel 3‐(5‐amino‐[1,3,4]thiadiazol‐2‐yl)‐2__H__‐pyrano[2,3‐c]pyridine‐2‐ones was developed. In the first step, a new 2__H__‐pyrano[2,3‐c]pyridine‐3‐carboxamide 5 was prepared by Knoevenagel condensation of pyridoxal hydrochloride with cyanoacetamide. In the second step, the reaction of carboxamide 5 with a series of N^4^‐substituted thiosemicarbazides yielded a library of 35 dis crete compounds 8{1–35} in high yields. The intermolecular recyclization mechanism leading to these products is discussed.