| 内容提要: |
Optically pure hinckdentine A was synthesized
on a 300 mg scale via an asymmetric catalysis-based
strategy. The key steps to the first asymmetric synthesis
involved (i) enantioselective dearomative cyclization of an
achiral N-acyl indole that allowed for the efficient construction
of the key polycyclic indoline intermediate with a
crucial tetrasubstituted stereogenic carbon center, (ii) Beckmann
fragmentation-mediated ring expansion, (iii) rearrangement-
based introduction of an anilinic nitrogen atom,
(iv) regioselective tribromination, and (v) final closure of
the cyclic amidine moiety. |