117570-53-3 5,6-Dimethyl xanthenone acetic acid 5,6-Dimethyl-9-oxo-9H-xanthene-4-acetic acid 5,6-Dimethylxanthenone-4-acetic acid 5,6-Mexaa 5,6-dimethylxanthenoneacetic acid 9H-Xanthene-4-acetic acid, 5,6-dimethyl-9-oxo- DMXAA Dimethyloxoxanthene acetic acid NSC 640488