Two new lignans, pre-gomisin (I) and gomisin J (II) have been isolated from the fruits of Schizandra chinensis BAILL. (Schizandraceae). Their structures were established by chemical and spectral evidence.
Synthesis of Lignans Based on a Borate‐mediated One‐pot Sequential Suzuki‐Miyaura Coupling of Cyclic Boranes
作者:Ko Sato、Hiroshi Tanaka
DOI:10.1002/chem.202100804
日期:2021.6.25
phytochemicals that possess a large spectrum of chemical structures and biological activities. Here the syntheses of lignans – anwulignan, burseran, dehydroxycubebin, ruburisandrin B, and sesamin – are achieved based on a borate-mediated one-pot sequential Suzuki-Miyaura coupling of cis- and trans-fused bicyclic boranes, which were prepared by diastereoselective cyclic hydroboration of exo-cyclic diene with
木脂素是一组多酚类植物化学物质,具有广泛的化学结构和生物活性。在这里,木脂素的合成——anwulignan、burseran、dehydroxycubebin、ruburisandrin B 和芝麻素——是基于硼酸盐介导的顺式和反式一锅序贯 Suzuki-Miyaura 偶联实现的-稠合双环硼烷,分别通过环戊基-和甲苯基硼烷对环外二烯进行非对映选择性环状硼氢化反应制备。每个环状硼酸酯与各种芳基溴化物的一锅顺序 Suzuki-Miyaura 偶联通过用碳亲核试剂活化环状硼烷引发,提供具有不同芳族取代基的 2,3-二苄基丁烷衍生物。最后,从 Suzuki-Miyaura 偶联的产物中分几个步骤完成了天然存在的木脂素的合成。
The constituents of Schizandra chinensis Baill. IV. The structures of two new lignans, pre-gomisin and gomisin J.
Two new lignans named pre-gomisin (1) and gomisin J (2) were isolated from the fruits of Schizandra chinensis BAILL. (Schizandraceae). The structure of the former was elucidated as (2S, 3R)-1, 4-bis (3´-hydroxy-4´, 5´-dimethoxyphenyl)-2, 3-dimethylbutane (1) by its preparation from guaiaretic acid. The structure and conformation of the latter were elucidated by chemical and spectral studies.