1.
Angew Chem Int Ed Engl
; 61(31): e202201213, 2022 08 01.
Artículo
en Inglés
| MEDLINE
| ID: mdl-35417620
RESUMEN
A 14-step synthesis of (+)-cochlearolâ B is reported. This renoprotective meroterpenoid features a unique core structure containing a densely substituted cyclobutane ring with three stereocenters. Our strategy employed an organocatalytic Kabbe condensation in route to the key chromenyl triflate. A subsequent Catellani reaction incorporated the remaining carbon atoms featured in the skeleton of cochlearolâ B. An ensuing visible-light-mediated [2+2] photocycloaddition closed the cyclobutane and formed the central bicyclo[3.2.0]heptane core. Notably, careful design and tuning of the Catellani and photocycloaddition reactions proved crucial in overcoming undesired reactivity, including cyclopropanation reactions and [4+2] cycloadditions.