异氰酸甲酯 、
7,7,9,9,7',7',9',9'-octamethyl-3,3'-{2,2'-dihydroxy-3,3'-[4,4'-(1-methyl-ethane-1,1-diyl)-diphenoxy]-dipropyl}-bis-1,3,8-triaza-spiro[4.5]decane-2,4-dione 在
silica gel 、
乙酸乙酯 、
苯 、
三乙胺 、
乙醇 作用下,
反应 8.5h,
以31 was obtained in the form of white crystals, melting point 238°-242° C.的产率得到7,7,9,9,7',7',9',9'-octamethyl-3,3'-{2,2'-bis-methylcarbamoyloxy-3,3'-[4,4'-(1-methyl-ethane-1,1-diyl)-diphenoxy]-dipropyl}-bis-1,3,8-triaza-spiro[4.5]decane-2,4-dione