Dimethyl (1R,8R)-1,11,11-trimethyl-2,3-diazatricyclo[6.2.1.02,6]undeca-3,5-diene-4,5-dicarboxylate, a chiral molecule with an approximate centrosymmetric crystal structure - Bats, Jan Willem; Gundl, Marc A.; Hashmi, A. Stephen K. (Acta crystallographica. Section C, Crystal structure communications, 2001)