2-Pentenoic acid, 4-oxo- 3-03-00-01310 (Beilstein Handbook Reference) 3-beta-Acetylacrylic acid 4-Ketopentenic acid 4-Oxo-2-pentenoic acid 4-Oxopent-2-en-2-oic acid 4743-82-2 Acetylacrylic acid BRN 1745249 EINECS 225-256-2 beta-Acetoacrylic acid