p. 986 - 992
(2007/10/07)(tert-Butoxycarbonylmethylene)triphenylphosphorane
(6R)-7t-acetylamino-3-hydroxymethyl-8-oxo-(6rH)-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid benzhydryl ester
(6R)-3-(2-carboxy-vinyl)-7t-((Ξ)-2-hydroxy-2-phenyl-acetylamino)-8-oxo-(6rH)-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid
(6R)-3-(2-tert-butoxycarbonyl-vinyl)-7t-((Ξ)-2-formyloxy-2-phenyl-acetylamino)-8-oxo-(6rH)-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid benzhydryl ester