Koniamborine, the First Pyrano[3,2-b]indole Alkaloid and Other Secondary Metabolites from Boronella koniambiensis
摘要:
Two new alkaloids,(-)-cis-1,2-dihydroxy- 1,2-dihydromedicosmine (3) and koniamborine (4), have been isolated from Boronella koniambiensis aerial parts. Their structures have been established from NMR and mass data. Koniamborine is a novel type of alkaloid, which derives from the pyrano[3,2-b]indole basic skeleton, described for the first time from nature. 6-Methoxy-1-methylisatin, also present in the plant material, can be considered biogenetically as a degradation product of the fused pyrone ring of 4.
A short synthesis of koniamborine, a naturally occurring pyrano[3,2-b]indole
作者:Ronald W. Clawson、Björn C.G. Söderberg
DOI:10.1016/j.tetlet.2007.06.092
日期:2007.8
An expedient synthesis of the alkaloid koniamborine, the only to date isolated naturallyoccurring pyrano[3,2-b]indole is presented. The key pyrano[3,2-b]indole forming step is a palladium-catalyzed reductive N-heteroannulation of 2-(4-methoxy-2-nitrophenyl)-(4H)-pyrane-4-one.
提出了生物碱可可宁的一种简便的合成方法,这是迄今为止唯一分离的天然吡喃并[3,2- b ]吲哚。关键的吡喃并[3,2- b ]吲哚形成步骤是2-(4-甲氧基-2-硝基苯基)-(4H)-吡喃-4-酮的钯催化的还原性N-杂环状。
Koniamborine, the First Pyrano[3,2-<i>b</i>]indole Alkaloid and Other Secondary Metabolites from <i>Boronella </i><i>k</i><i>oniambiensis</i>
Two new alkaloids,(-)-cis-1,2-dihydroxy- 1,2-dihydromedicosmine (3) and koniamborine (4), have been isolated from Boronella koniambiensis aerial parts. Their structures have been established from NMR and mass data. Koniamborine is a novel type of alkaloid, which derives from the pyrano[3,2-b]indole basic skeleton, described for the first time from nature. 6-Methoxy-1-methylisatin, also present in the plant material, can be considered biogenetically as a degradation product of the fused pyrone ring of 4.