90704-68-0Relevant articles and documents
The Synthesis of (3'-Oxo-3',4'-dihydro-2'H-1',4'-benzothiazin-2'-yl)acetic Acid and (3'-Oxo-3',4'-dihydro-2'H-1',4'-benzoxazin-2'-yl)acetic Acid Derivatives
Teitei, Tsutomu
, p. 503 - 510 (2007/10/02)
Reaction of o-aminophenol with various maleic anhydrides gave first 2-hydroxymaleanilic acids (4-(2'-hydroxyphenylamino)-4-oxobut-2-enoic acids) (1), which were then converted into the 3-oxo-1,4-benzoxazines (1d-h) and (3f-l) under mild basic conditions:
