{(7R,8R)-8-hydroxymethyl-1,4-dioxa-spiro[4.5]dec-7-yl}-carbamic acid benzyl ester

ethyl 7-oxo-1,4-dioxaspiro[4.5]decane-8-carboxylate

[(7R,8R)-7-((R)-1-phenyl-ethylamino)-1,4-dioxa-spiro[4.5]dec-8-yl]-methanol

(7R,8R)-7-((R)-1-phenyl-ethylamino)-1,4-dioxa-spiro[4.5]decane-8-carboxylic acid ethyl ester

(7R,8S)-7-((R)-1-phenyl-ethylamino)-1,4-dioxa-spiro[4.5]decane-8-carboxylic acid ethyl ester