1,2-Phenylene 5-oxo-2,4,8-trimethyl-6-oxa-3,9-dithia-2,4,7-triazadec-7-enoate 6-Oxa-3,9-dithia-2,4,7-triazadec-7-enoic acid, 5-oxo-2,4,8-trimethyl-, 1,2-phenylene ester 87767-36-0