Indole alkaloids from the roots of Isatis ingigotica and their antiherpes simplex virus type 2 (HSV-2) activity in vitro

Abstract

A new indole alkaloid 1, together with four known indole alkaloids 2-5, was isolated from the 95% EtOH extract of the traditional Chinese medicinal plant Isatis indigotica. Alkaloids 2-5 were found in the plant for the first time. Their structures were elucidated as 3-hydroxy-3-acetonitrile-4-hydroxy-2-indolone (1), 1-methoxy-3-indoleacetonitrile (2), 3-indoleacetic acid (3), 3-indolealdehyde (4), and 1-methoxy-3-indolecarbaldehyde (5) on the basis of spectroscopic data. Their anti-HSV effects in vitro were evaluated by plaque reduction assay.Keywords: Isatis indigotica, indole alkaloids, antiherpes simplex virus type 2 (HSV-2) activity. The root of Isatis indigotica Fort. (Brassicaceae), a traditional Chinese medicine, has been used to treat fever, phlogosis, headache, rheumatism, and viruses in China since ancient times [1]. Nowadays, it is routinely applied for the treatment of diseases such as catarrhal rhinitis, influenza, bacterial infection, sickness with the symptom of hypoimmunity, etc. that are caused by bacteria and virus infection [2, 3]. In the literature, many biological activities, including antiviral, have been reported for Isatis indigotica [4]. In previous studies, the constituents isolated from the plant are acids [5], alkaloids [6, 7], benzenoids [8, 9], flavonoids [10], lignans [11], amino acids [4], sterols [5], nucleosides [9], and sulfur-containing compounds [12].In this investigation, a new indole derivative (1), together with four indole compounds 2-5, which were separated for the first time, was isolated from the 95% EtOH extract of the traditional Chinese medicinal plant Isatis indigotica. Their structures were elucidated as 3-hydroxy-3-acetonitrile-4-hydroxyl-2-indolone (1), 1-methoxy-3-indoleacetonitrile (2), 3-indoleacetic acid (3), 3-indolealdehyde (4), and 1-methoxy-3-indolecarbaldehyde (5) on the basis of spectroscopic data. Their anti-HSV effects in vitro were evaluated by plaque reduction assay.Purification of the EtOAC fraction of the root of Isatis indigotica by several column chromatographic methods has afforded a new indole derivative 1. The structure elucidation of the indole compound was performed by HR-ESI-MS and 1D and 2D NMR experiments. Fig. 1. Partial HMBC correlations of 1.

A chromosome-scale genome assembly of Isatis indigotica, an important medicinal plant used in traditional Chinese medicine

“…The major active compounds isolated from this species comprise terpenoids, lignans, and indole alkaloids [14][15][16][17] . These compounds were confirmed to have antiviral 18,19 , antibacterial 20 , anti-inflammatory 21,22 , and antileukemia 23,24 functions. Previous studies based on transcriptomes revealed a few candidate genes involved in the biosynthesis of active compounds in this species [25][26][27][28] .…”

High-Throughput Sequencing and De Novo Assembly of the Isatis indigotica Transcriptome

“…Their common names are “Da-Qing-Ye”and “Ban-Lan-Gen”, respectively, in the Chinese Pharmacopeia [1] . Previous studies have shown that Da-Qing-Ye and Ban-Lan-Gen have a wide range of pharmacological bioactivities, including antivirus [2] , [3] , [4] , anti-bacterial [5] , anti-endotoxic [6] , antitumor [7] , anti-inflammatory [8] , [9] and immune regulatory effects [10] . Chemical research indicated that Da-Qing-Ye contains a substantial amount of alkaloids [4] , [11] , [12] , [13] , organic acids [14] , nucleosides [15] , ignanoids [16] , quinoline and quinazolone [17] .…”

Antiviral effects against EV71 of pimprinine and its derivatives isolated from Streptomyces sp

“…Natural substances offer an interesting pharmacological perspective for the development of novel antiviral drugs with broad-spectrum antiviral properties and novel modes of action. Some natural indole alkaloid compounds have been proven to have antiviral potential against dengue virus and HSV-2 [ 23 , 24 ]. In this study, we report novel findings that pimprinethine, WS-30581 A and WS-30581B, as natural indole alkaloids, were effective inhibitors of the replication of EV71 and ADV-7, with slight inhibitory activity against CVB3, HSV-1 and H1N1 (with a few exceptions).…”