6-((Isobutoxycarbonyl)amino)-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid compound with N~1~,N~2~-dibenzyl-1,2-ethanediamine (1:1) AIDS-156045 AIDS156045 NSC98947