T. Zoller et al., A C-B-A-D APPROACH TO BRASSINOSTEROIDS - GENERATION OF THE CIS-ANTI-TRANS A-B-C RING-SYSTEM, Tetrahedron letters, 38(19), 1997, pp. 3409-3412
Thermal intramolecular Diels-Alder cyclisation of the ketone C-1 proce
eds through an exo transition state to give the ketone CAT-2. (C) 1997
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