2-Oxa-7,9-diazabicyclo[4.2.2]decane-8,10-dione, 6-hydroxy-1-[(S)-hydroxy[(4S)-2,2,4-trimethyl-1,3-dioxolan-4-yl]methyl]-5 -[(4-pyridinylthio)methyl]-, (1S,6R)-