Download full text in PDF Opens in a new window. Article suggestions will be shown in a dialog on return to ScienceDirect. ... Please enable JavaScript to use all the features on this page. ... The dipolar cycloaddition reaction of α-methylene butyrolactone and N-benzyl azomethine ylid (5) affords the spirolactone (2) which rearranges to give ethyl 1-zabicyclo[2.2.1]hept-4-yl carboxylate (1) in excellent overall yield. ... Ester (1) is derived from the spirolactone (2) obtained ...
[Orlek, Barry S.; Blaney, Frank E.; Brown, Frank; Clark, Michael S. G.; Hadley, Michael S.; et al. Journal of Medicinal Chemistry, 1991 , vol. 34, # 9 p. 2726 - 2735]