Two new monoterpenoid indole alkaloids from the kernels of Kopsia arborea

Abstract

Two new monoterpenoid indole alkaloids, (2R, 7R, 16R, 20R, 21S)-12hydroxypleiocarpine (1) and (2S, 7R, 16S, 20R, 21S)-N-methoxycarbonyl-11,12methylenedioxy- 14,15 -kopsinaline (2), along with six known alkaloids were isolated from the methanol extract of the kernels of Kopsia arborea. Their structures including the absolute configurations were elucidated by HRESIMS, NMR spectroscopy, and quantum computational methods. Their cytotoxicity against two human cancer cell lines were also evaluated. Figure S2. 13 C NMR and DEPT spectra (125 MHz, chloroform-d) of 1 (↔) correlations of 1.

Divergent Total Synthesis of Four Kopsane Alkaloids: N‐Carbomethoxy‐10,22‐dioxokopsane, Epikopsanol‐10‐lactam, 10,22‐Dioxokopsane, and N‐Methylkopsanone

“…[1] A central group of these alkaloids is the kopsane-type alkaloids and the family is still growing (Figure 1). [1][2][3][4][5][6][7][8] Besides the promising biological activities, kopsane alkaloids feature an extraordinarily complex heptacyclic skeleton, which contains six to seven contiguous stereocenters including two quaternary centers. Thus, they pose a significant challenge in synthetic chemistry.…”