Organic Structure Challenge
$\ce{C20H18}$, 246 characters


InChI=1S/C20H18/c1-2-13(1)5-15(13)7-17(15)9-19(17)11-12(19)20(11)10-18(20)8-16(18)6-14(16)3-4-14/h1-4,11-12H,5-10H2/t11-,12+,15-,16-,17-,18-,19-,20-/m1/s1
PIN: (1'R,1''R,1'''R,1''''R,1'''''R,1''''''R,2''''R,3''''S)-octaspiro[tetrakis(cyclopropane)-1,2':1',2'':1'',2''':1''',4''''-bicyclo[1.1.0]butane-2'''',2''''':1''''',2'''''':1'''''',2''''''':1''''''',1''''''''-tetrakis(cyclopropane)]-2,2''''''''-diene