NEW STRATEGY FOR THE SYNTHESIS OF THE TAXANE DITERPENES - FORMATION OF THE BC-RINGS OF TAXOL VIA A [5+2]-PYRYLIUM YLIDE-ALKENE CYCLIZATION, RING EXPANSION STRATEGY - Bauta, W; Booth, J; Bos, M; Deluca, M; Diorazio, L; Donohoe, T; Magnus, N; Magnus, P; Mendoza, J; Pye, P; Tarrant, J; Thom, S; et al. (1995)