e5negB1

;ethyl (3~{S},7~{R},10~{R},11~{R},13~{S})-4-[(3~{S},6~{R},8~{a}~{S})-1'-[(2~{S})-2-acetamido-3-(2-chlorophenyl)propanoyl]-5-oxidanylidene-spiro[1,2,3,8~{a}-tetrahydroindolizine-6,2'-pyrrolidine]-3-yl]carbonyl-11-ethyl-2-oxidanylidene-1,4-diazatricyclo[8.3.0.0^{3,7}]tridec-8-ene-13-carboxylate ;