p. 8313 - 8319
(2007/10/03)(6R)-3t-bromo-3c-methyl-8-oxo-7t-(2-phenoxy-acetylamino)-(6rH)-5-thia-1-aza-bicyclo[4.2.0]octane-2c-carboxylic acid 4-nitro-benzyl ester
(R)-2-[(2R,3R)-2-Chlorosulfinyl-4-oxo-3-(2-phenoxy-acetylamino)-azetidin-1-yl]-3-methyl-but-3-enoic acid 4-nitro-benzyl ester
(6R)-3t-bromo-3c-methyl-5t,8-dioxo-7t-(2-phenoxy-acetylamino)-(6rH)-5λ4-thia-1-aza-bicyclo[4.2.0]octane-2c-carboxylic acid 4-nitro-benzyl ester
(2R,6R,7R)-1-aza-3-methylene-7-<5R-5-p-nitrobenzyloxycarbonylamino-5-p-nitrobenzyloxycarbonylpentaamido>-8-oxo-5-thia-bicyclo<4.2.0>octane-2-carboxylic acid p-nitrobenzyl ester
(2R,6R,7R)-7-Amino-3-methylene-8-oxo-5-thia-1-aza-bicyclo[4.2.0]octane-2-carboxylic acid 4-nitro-benzyl ester; hydrochloride
p-Nitrobenzyl 7-(phenoxyacetamido)-3-methylenecepham-4-carboxylate
(6R)-3-methylene-8-oxo-7t-(2-phenoxy-acetylamino)-(6rH)-5-thia-1-aza-bicyclo[4.2.0]octane-2c-carboxylic acid 4-nitro-benzyl ester