p. 2273 - 2283
(2007/10/02)3,4-cis-3-benzyloxycarbonylamino-4-carbamoyloxymethyl-1-(1-carboxy-2-methylpropyl)-2-azetidinone
(3S,4S) 3-<(benzyloxycarbonyl)amino>-4-<(carbamoyloxy)methyl>-2-azetidinone
(3S,4S)-3-benzyloxycarbonylamino-4-hydroxymethyl-2-azetidinone
(3S,4S)-3-benzyloxycarbonylamino-1-(1-carboxy-2-methylpropyl)-4-hydroxymethyl-2-azetidinone