Calophyline A, a New Rearranged Monoterpenoid Indole Alkaloid from Winchia calophylla

Abstract

Calophyline A (1), a novel unprecedented rearranged monoterpenoid indole alkaloid, along with a new natural product N-methyl aspidodasycarpine (2) and six known analogues, was isolated from the trunk barks of Winchia calophylla. The structure of compound 1 was elucidated on the basis of spectroscopic data and then confirmed by a single-crystal X-ray crystallographic analysis. A hypothetical biogenetic pathway for compound 1 was proposed. All isolated compounds were evaluated for their in vitro cytotoxicity against a small panel of human cancer cell lines.

Total Synthesis of the Monoterpenoid Indole Alkaloid (±)‐Aspidophylline A

“…[7] In the past decades, considerable efforts have been directed toward synthetic studies of these alkaloids. [8][9][10][11] These studies have resulted in three total syntheses of vincorine (5), [9] two total syntheses of scholarisine A (6), [10] and a total synthesis of aspidophylline A in 2011 by the Garg research group. [11] In pursuit of a general strategy for assembling akuammiline alkaloids, we recently completed the enantioselective total synthesis of vincorine [9b] by using an intramolecular oxidative coupling [8i, k 12, 13] between indole and malonate moieties as the key step.…”

“…Since akuammiline (1, Scheme 1) was characterized in 1932, [1] more than 100 akuammiline monoterpenoid indole alkaloids have been discovered from different medicinal plants. [2][3][4][5] Preliminary studies have indicated that these natural products possess a wide range of biological activity, such as the reversal of drug resistance in drug-resistant KB cells by aspidophylline A (2), [3] the in vivo antiinflammatory and analgesic activity exhibited by pseudoakuammigine (3), [6] and the mixed type of competitive and noncompetitive antagonism displayed by corymine (4) at the glycine receptor. [7] In the past decades, considerable efforts have been directed toward synthetic studies of these alkaloids.…”

Analysis of Monoterpenoid Indole Alkaloids Using Electrospray Ionization Tandem Mass Spectrometry

“…Mass spectrometry (MS), especially tandem mass spectrometry (MS/MS), is an important physicochemical method for the identification of alkaloids such as vinca alkaloids [8], plumeran indole alkaloids [9], epipolythiodioxopiperazines [10, 11], communesins [12], and uleine alkaloids [13]. In our laboratory, three monoterpenoid indole alkaloids with unique skeletons, that is echitaminic acid, N b -demethylechitamine, and N-methyl aspidodasycarpine, were isolated from the trunk barks of Winchia calophylla [14][15][16][17]. To our knowledge, these indole alkaloids have not been studied in detail by electrospray ionization (ESI)-MS/MS.…”

Electrospray ionization tandem mass spectrometry of uleine alkaloids

“…1), were isolated from the trunk bark of Winchia calophylla. [14][15][16] To our knowledge, uleine alkaloids have not been studied in detail by electrospray ionization (ESI)-MS/MS. The aim of the study was to obtain sufficient information on the structural elucidation of this class of compounds, such as their degradation products, metabolites, and biosynthetic intermediates.…”

“…The uleine alkaloids were isolated from the trunk bark of Winchia calophylla. [16] MS experiments were performed on a Bruker micrOTOF-Q mass spectrometer (Bremen, Germany). The mass resolution was 10 000 FWHM (full width at half maximum) at 922 u. Argon was used as the collision gas and high-purity nitrogen as the nebulizer and drying gas at flow rates of 0.3 and 4.0 L/min, respectively.…”