New methods for the synthesis of 2-aminothiazolones
Seb Caille1, Eric A Bercot, Sheng Cui
1Chemical Process R&D, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, USA. scaille@amgen.com
Abstract:
Two new methods for the synthesis of 2-aminothiazolones from 2-(4-methoxybenzylthio)acetic acids are described. A single reagent and simple experimental conditions are used in the key tandem deprotection-cyclization process. In the first approach 2-aminothiazolones are directly accessed via cyclization of the corresponding N-acylisothioureas. The second complementary approach provides access to a variety of 2-thiomethylthiazolones via cyclization of N-acyldithioimidates. The product 2-thiomethylthiazolones are then efficiently converted to 2-aminothiazolones via amine displacement.
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