O-Methylmurrayamine A (7) and 7-methoxymurrayacine (8) are natural products isolated from Murraya koenigii and Murraya siamensis, respectively. In this paper, we report the synthesis of 7 and 8 which are featured in the key step of cyclization to form carbazole intermediate 5 with mild conditions. The structures were confirmed by H-1 NMR, C-13 NMR, and HR-ESI-MS. In addition, compounds 7 and 8 were tested for their neuroprotective effects against H2O2 -induced PC12 cell damage. The results showed that compounds 7 and 8 have neuroprotective effect.
Murrayamine-A,-B,-C and (+)-mahanine, carbazole alkaloids from Murraya euchrestifolia
作者:Tian-Shung Wu
DOI:10.1016/0031-9422(91)85313-o
日期:1991.1
Four new carbazole alkaloids, murrayamine-A, -B, -C and (+)-mahanine, were isolated from leaves of Murraya euchrestifolia. Two known carbazole alkaloids, mahanimbine and girinimbine and a triterpenoid, fredelin and a carotenoid, beta-carotene together with p-hydroquinone were also isolated and characterized. The absolute configuration of (+)-mahanine was determined as 3'S. Murrayamine-A and (+)-mahanine showed significant cytotoxity.
YAMAMOTO, TATSUO;IMAGAWA, MASUMI T.;YABE, YUMIKO T.;SUWABE, ERIKO M.;MURA+, J. CHEM. SOC. PERKIN TRANS. PT 1,(1990) N1, C. 3003-3009
WU, TIAN-SHUNG, PHYTOCHEMISTRY, 30,(1991) N, C. 1048-1051
作者:WU, TIAN-SHUNG
DOI:——
日期:——
Palladium(<scp>ii</scp>)-catalysed total synthesis of naturally occurring pyrano[3,2-<i>a</i>]carbazole and pyrano[2,3-<i>b</i>]carbazole alkaloids
作者:Ronny Hesse、Anne Jäger、Arndt W. Schmidt、Hans-Joachim Knölker
DOI:10.1039/c4ob00367e
日期:——
Seven naturallyoccurring pyranocarbazole alkaloids (pyrayafoline A–E, O-methylmurrayamine A and O-methylmahanine) have been obtained by totalsynthesis using a palladium(II)-catalysed oxidative cyclisation of a diarylamine to an orthogonally diprotected 2,7-dihydroxycarbazole as key step.