triethyloxonium fluoroborate 、
4-{N'-[3-(2-Methoxycarbonyl-ethyl)-4-methyl-5-[3-methyl-5-oxo-4-vinyl-1,5-dihydro-pyrrol-(2Z)-ylidenemethyl]-pyrrol-(2Z)-ylidene]-hydrazino}-benzoic acid ethyl ester 生成 4-[5-[5-Ethoxy-3-methyl-4-vinyl-pyrrol-(2Z)-ylidenemethyl]-3-(2-methoxycarbonyl-ethyl)-4-methyl-1H-pyrrol-2-ylazo]-benzoic acid ethyl ester