Competent Route to Unsymmetric Dimer Architectures: Total Syntheses of (−)-Lycodine and (−)-Complanadines A and B, and Evaluation of Their Neurite Outgrowth Activities
作者:Le Zhao、Chihiro Tsukano、Eunsang Kwon、Hisashi Shirakawa、Shuji Kaneko、Yoshiji Takemoto、Masahiro Hirama
DOI:10.1002/chem.201604647
日期:2017.1.18
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)
有价值的合成路线到石松生物碱lycodine(1)和它的非对称的二聚物,complanadines A(4)和B(5),已被开发。可以通过远程功能控制的Diels-Alder反应和随后的分子内Mizoroki-Heck反应实现莱科定双环[3.3.1]壬烷核心结构的区域选择性构建。通过在66的C1位置进行CH芳基化反应,可以使lycodine单元,吡啶N-氧化物(66)和芳基溴化物(65)发生关键的偶联反应在合成后期提供了不对称的二聚体结构。该策略大大简化了二聚体体系结构和功能化的构建。Complanadines A(4)和B(5)中,通过调整单-联吡啶的氧化水平合成Ñ氧化物(67)。这种常见中间体(67)的多种用途表明在自然界中可能存在Complanadines的生物合成途径。lycodine(1)和complanadines A(4)和B(5)的对映体。)的量足以进行生物学评估。在PC-