The first asymmetric total synthesis of new biphenylquinolizidine alkaloids 4″--demethyllythridine and 14--4″--demethyllythridine isolated from was accomplished. The key steps in the synthesis were a copper(I)-catalyzed asymmetric intramolecular aza-Michael reaction to build a chiral 4-arylquinolizidine unit and an intramolecular Suzuki-Miyaura cross-coupling reaction to construct a macrolactone ring comprising a biphenyl moiety.
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