Synthesis of tri- and tetracyclic diterpenes. Cyclisations promoted by SmI 2

1. Marcos, I.S.
2. Cubillo, M.A.
3. Moro, R.F.
4. Carballares, S.
5. Díez, D.
6. Basabe, P.
7. Llamazares, C.F.
8. Benéitez, A.
9. Sanz, F.
10. Broughton, H.B.
11. Urones, J.G.