Ethyl 3-(4-cyano-3-(trifluoromethyl)-phenyl)-2,4-dioxo-8-thia-1,3-diazaspiro[4.5]-decan-1-butanoate 、
sodium hydroxide 、
盐酸 以
甲醇 为溶剂,
反应 3.5h,
以95-5 as eluant to obtain 346 mg of the expected product (white crystals) melting at 197-198° C.的产率得到3-(4-cyano-3-(trifluoromethyl)-phenyl)-2,4-dioxo-8-thia-1,3-diazaspiro[4.5]decane-1-butanoic acid