6,7-Dichloro-3-nitro-1,2,3,4-tetrahydro-naphthalene-2-carboxylic acid ethyl ester

(5S,6S)-6-tert-Butoxycarbonylamino-5-hydroxy-cyclohexa-1,3-dienecarboxylic acid ethyl ester

6,7-Dichloro-3-nitro-naphthalene-2-carboxylic acid ethyl ester

(2R,3S,7R,8S,8aR)-3-Benzyloxy-2-benzyloxymethyl-8-tert-butoxycarbonylamino-3,4,6,7,8,8a-hexahydro-2H-chromene-7-carboxylic acid ethyl ester

(2R,3R,7R,8S,8aR)-3-Benzyloxy-2-benzyloxymethyl-8-tert-butoxycarbonylamino-3,4,6,7,8,8a-hexahydro-2H-chromene-7-carboxylic acid ethyl ester