The Structures of Gardnerine, Gardnutine and Hydroxygardnutine and the Absolute Configuration of Gardnerine
作者:SHIN-ICHIRO SAKAI、AKINORI KUBO、TAKENORI HAMAMOTO、MIKIO WAKABAYASHI、KATSUHIRO TAKAHASHI、HIROYUKI OHTANI、JOJU HAGINIWA
DOI:10.1248/cpb.21.1783
日期:——
Four kinds of indole alkaloids, gardneramine, gardnerine, gardnutine and hydroxygardnutine, were isolated from Gardneria nutans SIEB. et ZUCC. (Horaikazura). Among them, gardnerine, gardnutine and hydroxygardnutine were examined and the structures, I, II and III were assigned respectively to gardnerine, gardnutine and hydroxygardnutine on the basis of chemical and physical data. The main alkaloid gardnerine (I) was interrelated with ajmaline (IV)(of established absolute configuration) by two different routes (A and B). In the route A, I was transformed to 1-demethyl-Δ1-17, 21-dideoxyajmaline (XXVIII) which in turn was erived from ajmaline (IV). On the other hand, in the route B, I was transformed to XXXII which in turn was derived from isoajmaline (XXXV)(C20-ethyl epimer of ajmaline). The stereochemistry of the ethylidene side chain of II was determined by NOE measurement. These correlations as well as the nuclear overhauser effect (NOE) experiment established the absolute stereochemistry of I, II and III as shown in Chart 15.
从加德纳纳豆(Gardneria nutans SIEB. et ZUCC.)中分离出四种吲哚生物碱,即加德纳胺(gardneramine)、加德纳宁(gardnerine)、加德纳宁(gardnutine)和羟基加德纳宁(hydroxygardnutine)。(Horaikazura)中分离得到。根据化学和物理数据,对其中的加德纳林碱、加德纳林碱和羟基加德纳林碱进行了研究,并分别确定了加德纳林碱、加德纳林碱和羟基加德纳林碱的结构 I、II 和 III。主要生物碱加德纳碱(I)通过两种不同的途径(A 和 B)与阿吉马林碱(IV)(已确定绝对构型)相互关联。在路线 A 中,I 被转化为 1-去甲基-Δ1-17, 21-二脱氧刺五加碱 (XXVIII),而刺五加碱 (XXVIII)又是从刺五加碱 (IV) 中提取出来的。另一方面,在路线 B 中,I 转化为 XXXII,而 XXXII 又来自异颉马林 (XXXV)(颉马林的 C20-乙基外延物)。II 亚乙基侧链的立体化学结构是通过 NOE 测量确定的。如图 15 所示,这些相关性以及核超豪效应(NOE)实验确定了 I、II 和 III 的绝对立体化学结构。