(4R,5S,6S,7R)-hexahydro-5,6-O-isopropylidene-4,7-bis(phenylmethyl)-2H-1,3-diazepin-2-one 、
4-(tert-butyloxymethyl)benzyl chloride 在
potassium tert-butylate 作用下,
以
四氢呋喃 为溶剂,
生成 (3aS,4R,8R,8aS)-4,8-Dibenzyl-5,7-bis-(4-tert-butoxymethyl-benzyl)-2,2-dimethyl-hexahydro-1,3-dioxa-5,7-diaza-azulen-6-one