C. V.  Ramana, Suryawanshi, S. B., and Gonnade, R. G., ?Pd(II)-mediated alkynediol spiroketalization: first total synthesis of (-)-cephalosporolide E and (+)-cephalosporolide F?, Journal of Organic Chemistry, vol. 74, no. 7, pp. 2842-2845, 2009.