29637-29-4 4-(4-(4-(3-Ethyl-benzoxazol-2(3H)-ylidene)buten-2-ylidene)-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl)benzenesulphonic acid Benzenesulfonic acid, 4-(4-(4-(3-ethyl-2(3H)-benzoxazolylidene)-2-butenylidene)-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl)- EINECS 249-746-0