✦ LIBER ✦
A modified approach to C-14-labeled 2-(3,4-difluorophenoxy)-5-fluoronicotinic acid and other halogen-substituted analogs
✍ Scribed by Yinsheng Zhang; Zhigang Jian; Wayne T. Stolle
- Publisher
- John Wiley and Sons
- Year
- 2011
- Tongue
- French
- Weight
- 153 KB
- Volume
- 54
- Category
- Article
- ISSN
- 0022-2135
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
A modified approach to a carbon‐14‐labeled pyridine ring system was developed based on the electrocyclic ring‐closure of 1,4,4‐trisubstituted butadiene. The new method was applied to prepare 2‐(3,4‐difluorophenoxy)‐5‐fluoro‐[2‐^14^C] nicotinic acid and other halogen‐substituted analogs. The targeted compound was isolated with a radiochemical purity of >98% and a specific activity of 53 mCi/mmol from four radiochemical steps, starting from ethyl [1‐^14^C] cyanoacetate in an overall radiochemical yield of 39%. Copyright © 2011 John Wiley & Sons, Ltd.