Anti‐HIV‐1 constituents from Clausena excavata: Part II. carbazoles and a pyranocoumarin

Abstract

Three carbazole derivatives, O-methylmukonal (1), 3-formyl-2,7-dimethoxycarbazole (2) and clauszoline J (3), and a pyranocoumarin, clausenidin (4), were isolated from the rhizomes and roots of Clausena excavata. Compound 1, isolated from this plant for the first time, has not been reported previously as having anti-HIV-1 activity. Compounds 1-4 displayed anti-HIV-1 activity in a syncytial assay with EC(50) values of 12, 29.1, 34.2 and 5.3 microm, respectively, and thus exhibited potential therapeutic index (PTI) values of 56.7, 8.0, 1.6 and 7.0, respectively. All isolated compounds demonstrated a lack of cytotoxicity against the KB and BC-1 cancer cell lines.

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“…Activity guided fractionation of the crude hexane extract led to the isolation of 5 carbazoles: heptaphylline (1), 7-methoxyheptaphylline (2), 7-methoxymukonal (5), 7-hydroxyheptaphylline (6), and clausine C (7), as well as 2 coumarins: dentatin (3) and xanthoxyletin (4). In addition, the purification of the crude EtOAc extract afforded a coumarin: nordentatin (8), and 4 carbazoles: 7-methoxymurrayacine (9), clausine E (10), lansine (11), and clausine K (12). The structures of all compounds were identified by spectroscopic methods (IR, 1D and 2D NMR, HRMS) together with the comparison of their spectroscopic data with literature values.…”

“…During previous investigations of this plant, carbazoles and coumarins have been isolated and evaluated for antimalarial, antifungal, anti TB, and cytotoxicity 7,8 . Moreover, carbazole alkaloids exhibit many activities such as topoisomerase II inhibition 9 , antiplatelet aggregating, and vasorelaxing activities 10 , antimycobacterial, anti-inflammatory 11 , anti HIV-1 agents 12 , and cytotoxicity against the human leukaemia cell line HL-60 13 . Biological activities of coumarins include antibacterial and antitumor promoting activity, as well as an inhibitory effect on iNOS protein expression 11 .…”

A New Coumarin and Carbazole Alkaloid from Clausena vestita D. D. Tao

“…Plants of the genus Clausena have been extensively subjected to phytochemical investigations [1 -23]. In addition, various biological activities have been demonstrated, such as antimycobacterial [2], antifungal [2], antiplatelet [5] [6], antitumor [7], antiplasmodial [8], antimicrobial [9], antituberculosis [24], and anti-HIV activities [25]. Clausena vestita D. D. Tao is an endemic species of China distributed in Yunnan Province.…”

Alkaloids from the stems of Clausena lansium and their neuroprotective activity

“…IR spectra were recorded on a Nicolet 5700 spectrometer using an FT-IR microscope transmission method. NMR spectra were acquired with Bruker AVIIIHD 600, VNS-600, and Mercury-400 spectrometers in DMSO-d 6 and MeOH-d 6 . HRESIMS spectra were collected on an Agilent 1100 series LC/MSD ion trap mass spectrometer.…”