1448802-15-0Relevant articles and documents
Competent Route to Unsymmetric Dimer Architectures: Total Syntheses of (?)-Lycodine and (?)-Complanadines A and B, and Evaluation of Their Neurite Outgrowth Activities
Zhao, Le,Tsukano, Chihiro,Kwon, Eunsang,Shirakawa, Hisashi,Kaneko, Shuji,Takemoto, Yoshiji,Hirama, Masahiro
, p. 802 - 812 (2017/02/05)
Valuable synthetic routes to the Lycopodium alkaloid lycodine (1) and its unsymmetric dimers, complanadines A (4) and B (5), have been developed. Regioselective construction of the bicyclo[3.3.1]nonane core structure of lycodine was achieved by a remote functionality-controlled Diels–Alder reaction and subsequent intramolecular Mizoroki–Heck reaction. A key coupling reaction of the lycodine units, pyridine N-oxide (66) and aryl bromide (65), through C?H arylation at the C1 position of 66 provided the unsymmetric dimer structure at a late stage of the synthesis. This strategy greatly simplified the construction of the dimeric architecture and functionalization. Complanadines A (4) and B (5) were synthesized by adjusting the oxidation level of the bipyridine mono-N-oxide (67). The diverse utility of this common intermediate (67) suggests a possible biosynthetic pathway of complanadines in Nature. Both enantiomers of lycodine (1) and complanadines A (4) and B (5) were prepared in sufficient quantities for biological evaluation. The effect on neuron differentiation of PC-12 cells upon treatment with culture medium, in which human astrocytoma cells had been cultured in the presence of 1, 4, or 5 was evaluated.
