8-benzoyl-6-(1-hydroxyimino-ethyl)-1,4-dioxa-8-aza-spiro[4.5]decane
6-acetyl-8-benzoyl-1,4-dioxa-8-aza-spiro[4.5]decane
8-benzoyl-1,4-dioxa-8-aza-spiro[4.5]decane-6-carboxylic acid
8-benzoyl-1,4-dioxa-8-aza-spiro[4.5]decane-6-carboxylic acid ethyl ester
8-benzoyl-6-(imidazole-1-carbonyl)-1,4-dioxa-8-aza-spiro[4.5]decane