4-Nitrobenzyl 2-((1R,5R)-3-benzyl-7-oxo-4-thia-2,6-Diazabicyclo[3.2.0]hept-2-en-6-yl)-3-methylbut-2-enoate 1g

4-Nitrobenzyl 2-((1R,5R)-3-benzyl-7-oxo-4-thia-2,6-Diazabicyclo[3.2.0]hept-2-en-6-yl)-3-methylbut-2-enoate 1g