Publication Cover
Synthetic Communications
An International Journal for Rapid Communication of Synthetic Organic Chemistry
Volume 37, 2007 - Issue 1
179
Views
10
CrossRef citations to date
0
Altmetric
Original Articles

New Straightforward Synthesis of2‐Amino‐6‐methyl‐5‐(pyridin‐4‐ylsulfanyl)‐3H‐quinazolin‐4‐one

&
Pages 53-61 | Received 31 Jan 2006, Published online: 25 Jul 2007
 

Abstract

The synthesis of 2‐amino‐6‐methyl‐5‐(pyridin‐4‐ylsulfanyl)‐3H‐quinazolin‐4‐one (1) was studied via three different synthetic routes starting from 4‐bromo‐5‐methylisatin. The best route was established, which is a straightforward route via 2‐guanidino‐5‐bromo‐6‐methyl‐quinazolin‐4‐one (6) as the key intermediate and a one‐pot synthesis by treatment of compound 6 with 4‐mercaptopyridine and KOH via the Ullmann reaction. When removing the amidino group from 2‐guanyl of compound 6 under strong alkaline conditions, surprisingly we found that 4‐mercaptopyridine could prevent the bromo group on a quinazoline ring from substitution by a hydroxyl group. Furthermore we found that 4‐mercaptopyridine analogues such as hydroxypyridinones also play a role of protecting agent in such a reaction system.

Acknowledgment

This work was partially supported by grants from the Guangdong Provincial Natural Science Foundation (No. 994078) and Foundation of Jinan University. We are grateful to Kai‐Bei Yu of Chengdu Institute of Organic Chemistry for performing the X‐ray crystallographic analysis and Zhongshan University Analyses Center for NMR, MS, and elemental analyses.

Log in via your institution

Log in to Taylor & Francis Online

PDF download + Online access

  • 48 hours access to article PDF & online version
  • Article PDF can be downloaded
  • Article PDF can be printed
USD 61.00 Add to cart

Issue Purchase

  • 30 days online access to complete issue
  • Article PDFs can be downloaded
  • Article PDFs can be printed
USD 422.00 Add to cart

* Local tax will be added as applicable

Related Research

People also read lists articles that other readers of this article have read.

Recommended articles lists articles that we recommend and is powered by our AI driven recommendation engine.

Cited by lists all citing articles based on Crossref citations.
Articles with the Crossref icon will open in a new tab.