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Nicotabaflavonoidglycoside (1), a novel cembrane-type diterpenoid and flavonoid heterodimer had been isolated from the leaves of Nicotiana tabacum. Its structure was elucidated as (1″S, 6″S) or (1″R, 6″R)-8-[6″-((-)-(1″S, 2″E, 4″Z, 7″E, 11″E)-cembra-2″, 4″, 7″, 11″-tetraenyl)]-rutin by comprehensive analyses of the NMR and HRESIMS spectra. Its absolute configurations of C-1″ and C-6″ were assigned as (1″S, 6″S) by its biogenesis and electronic circular dichroism (ECD). A possible biogenesis involving eliminate reaction of (1S, 2E, 4S, 6R, 7E, 11E)-2, 7, 11-cembratriene-4, 6-diol or its 4R isomer, as well as electrophilic substitution reaction of rutin was postulated.

Two new sesquiterpenoid glycosides, nicotabalactonecoside (1) and nicotabadiolcoside (2), along with four known terpenoids (3-6) were isolated from the leaves of Nicotiana tabacum. The structures of compounds 1 and 2 were determined as dihydrodeacetylphytuberin-2-one 11-O-β-D-glucopyranoside and 1,2-dehydro-4-epieremophil-9-ene-11,12-diol 12-O-β-D-glucopyranoside by extensive spectroscopic analyses (HR-ESI-MS, UV, IR, 1D, and 2D NMR) and chemical method. Compound 1 is an unusual phytuberin-type sesquiterpenoid with a 6/5/5 tricyclic system.

(+)-Paeoveitol and (-)-paeoveitol, a pair of new norditerpene enantiomers, were isolated from the root of Paeonia veitchii. Their structures and absolute configurations were determined on the basis of extensive analysis of 1D and 2D NMR spectra, crystal X-ray diffraction, and electronic circular dichroism (ECD). A possible biogenesis involving two molecules of paeoniflorin was postulated.

To study the chemical constituents of Lepidium meyenii, the air-dried rhizome of L. meyenii was extracted with 70% EtOH. The extract was condensed to a small amount of volume and extracted with petroleum ether, EtOAc and n-BuOH, successively. The compounds were isolated and purified by column chromatography, and identified based on spectral analyses (1H-NMR, 13C-NMR, HRESIMS). Eighteen compounds were isolated from L. meyenii, including 7 alkaloids and 4 fatty acids and 7 other compounds. They were characterized as (3-hydroxybenzyl) carbamic acid(1), phenylmethanamine(2), N-benzylformamide (3), N-benzylacetamide (4), pyridin-4-ylmethanamine(5), n-(4-methoxybenzyl) aniline(6), uracil(7), succininc acid(8), decanedioic acid(9), n-hexa- decanoic acid methyl ester(10), heptanoic acid(11), solerole(12), pyromucic acid methyl ester(13), 5-hydroxymethyl-2-furancar- boxadehyde(14), 5-(methoxymethyl)-1H-pyrrole-2-carbaldehyde(15), 1,7-dihydroxy-2,3, 4-trimethoxyxanthone (16), 1,7-di- hydroxy-3,4- dimethoxy-xanthone(17), (+)-pinoresinol(18). Meanwhile, compounds 1-18 were obtained from L. neyenii for the first time.

In this paper, the chemical constituents and bioactivities of leaves of Nicotiana tabacum were investigated. Six compounds were isolated by means of various chromatographic techniques (silica gel, Sephadex LH-20, MCI GEL CHP-20P and HPLC), and their structures were elucidated as cis-5'-(2-oxopropyl)-nicotine (1), 3-O-(9, 12, 15-octadecatrienoyl)-glyceryl-β-D-galactppyranoside (2), (l'R, 2R, 5S, 10R)-2-(1', 2'-dihydroxy-l'-methylethyl)-6, 10-dimethylspiro [4, 5] dec-6-en-8-one (3), (l'S, 2R, 5S, l0R)-2-(1', 2'-dihydroxy-l'-methylethyl)-6, 10-dimethylspiro [4, 5] dec-6-en-8-one (4),2, 3-dihydroxypropyl-β-D-galactoside (5) and phenylethyl β-D-glucopyranoside (6) by extensive spectroscopic analyses (UV, IR, MS, 1D- and 2D-NMR). Among them, compound 1 is a new alkaloid, and compounds 2-6 are isolated for the first time from N. tabacum. Compounds 1 and 2 were assayed for agitating activities on transient receptor potential vanilloid 1 (TRPV1), melatonin receptor 1 and 2 (MT1 and MT2), 1 showed agitating rate of 55.41% (1.53mmol•L⁻¹) on MT2 and 2 possessed agitating rate of 128.11% (0.59 mmol•L⁻¹) and 52.00% (0.73mmol•L⁻¹) on TRPV1 and MT1, respectively.

Investigation on the fruits of Melia toosendan afforded seven new lignans (1-7), along with seventeen known compounds (8-24). The structures of the new compounds, involving four neo-lignans (1-4), two sesquilignans (5-6), and a nor-lignan (7), were elucidated based on extensive spectroscopic analyses (high-resolution electrospray ionization mass spectra, ultraviolet, infrared, one-dimensional and two-dimensional nuclear magnetic resonance). Compound 24 exhibited activity on melatonin receptor type 1 with an agonistic rate of 57.77% at 1.02 mM according to the assay on HEK293 cell lines in vitro.

The rhizome of Cyperus rotundus (C. rotundus) is a well-known traditional Chinese medicine to cure hepatitis in many formulae, but the active components responsible for hepatitis have not been elucidated. According to our bioassay on HepG2.2.15 cell line in vitro, the ethanol extract of C. rotundus demonstrated potent anti-HBV activity. This current study was designed to isolate and identify the anti-HBV active constituents from the rhizomes of C. rotundus.Bioactivity and LC-MS guided fractionation on the extract of C. rotundus using various chromatographic techniques including open-column, Sephadex LH-20 and semi-preparative high performance liquid chromatography led to the isolation and identification of thirty-seven sesquiterpenoids. Structural elucidation of the isolates was carried out by extensive spectroscopic analyses (UV, IR, HRMS, 1D- and 2D -NMR). The anti-HBV activity and cytotoxicity were evaluated on the HBV-transfected HepG2.2.15 cell line in vitro. The cytotoxicity effects of the isolates were assessed by a MTT assay. The secretions of HBsAg and HBeAg in the culture medium were detected by ELISA method, and the load of HBV DNA was quantified by real-time fluorescent PCR technique.Five new patchoulane-type sesquiterpenoids, namely cyperene-3, 8-dione (1), 14-hydroxy cyperotundone (2), 14-acetoxy cyperotundone (3), 3β-hydroxycyperenoic acid (4) and sugetriol-3, 9-diacetate (5), along with 32 known sesquiterpenoids were isolated from the active fractions of C. rotundus. Compounds 2 and 3 were the first cyperotundone-type sesquiterpenoids with a hydroxyl group at C-14 position. Nine eudesmane-type sesquiterpenoids (15-21 and 23-24) significantly inhibited the HBV DNA replication with IC50 values of 42.7±5.9, 22.5±1.9, 13.2±1.2, 10.1±0.7, 14.1±1.1, 15.3±2.7, 13.8±0.9, 19.7±2.1 and 11.9±0.6 μM, respectively, of which, compounds 17, 21, 23 and 24 possessed high SI values of 250.4, 125.5,259.6 and 127.5, respectively. Two patchoulane-type sesquiterpenoids (4 and 7) effectively suppressed the secretion of HBsAg in a dose-dependent manner with IC50 values of 46.6±14.3 (SI=31.0) and 77.2±13.0 (SI=1.7) μM, respectively. Compounds 2, 8, 12, 15, 17 and 25 possessed moderate activities against HBeAg secretion with IC50 values of 162.5±18.9 (SI=13.3), 399.2±90.0 (SI=10.6), 274.7±70.8 (SI=5.2), 313.9±87.5 (SI=7.2), 334.0±70.4 (SI=9.9) and 285.3±20.9 (SI=15.5) μM, respectively.This is the first study to reveal the anti-HBV constituents of C. rotundus, demonstrating that the eudesmane-type sesquiterpenoids might contribute to the anti-HBV activity of the rhizomes of C. rotundus.

Six new 14-noreudesmane sesquiterpenoids, nicotabacosides A-F (1-6), along with five known sesquiterpenoids (7-11), were isolated from the leaves of Nicotiana tabacum. The structures of compounds 1-6 were elucidated as isorishitin 3-O-beta-D-glucopyranoside (1), rishitin 3-O-beta-D-glucopyranoside (2), rishitin 2-O-beta-D-glucopyranoside (3), 1, 6-dehydro-rishitin 3-O-beta-D-glucopyranoside (4), 2-hydroxyl-ligudentato 3-O-beta-D-glucopyranoside (5) and oxyglutinosone 3-O-beta-D-glucopyranoside (6) based on extensive spectroscopic analyses (HRESIMS, UV, IR, 1D and 2D NMR). Their absolute configurations were determined by X-ray single-crystal diffraction and comparison of their electronic circular dichroism (ECD) spectra. (C) 2014 Elsevier B.V. All rights reserved.

A new meta-homoisoflavane, 10,11-dihydroxydracaenone C (1), together with 7,4 '-dihydroxyflavone (2), 7,4 '-dihydroxyflavane (3), 4,4 '-dihydroxy-2-methoxychalcone (4), 4,4 '-dihydroxy-2-methoxydihydrochalcone (5), 7,4 '-dihydrohomoisoflavanone (6), 7,4 '-homoisoflavane (7), lophenol (8), beta-sitosterol (9), stigma-5, 22-diene-3-ol ( 10), 1-(4 '-O-beta-D-glucopyranosyl) benzyl-ethan-2-ol (11), 3,4-dihydoxy-1-allylbenezene-4-O-alpha-L-rhamnopyranosyl-(1 -> 6)-O-beta-D-glucopyranoside (12), 1-hydroxy-3,4,5-trimethoxybenzene1-O-alpha-L-apiopyranosyl-(1 -> 6)-O-beta-D-glucopyranoside (13), and tachioside (14) have been isolated from the fresh stems of Dracaena cochinchinensis. Their structures have been established by spectroscopic analysis, especially by 2D NMR. This is the first time compounds 11, 13, 14 have been isolated from Dracaena.