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Five new α-pyrone derivatives, cryptoyunnanes A − E (1 − 5), together with four known analogues, were isolated from the leaves and twigs of Cryptocarya yunnanensis. Their structures including absol...

In the aim to evaluate the functional food property of Cinnamomum bejolghota, seven new lignans and neolignans, bejolghotins A-G (1-4 and 9-11), along with 14 known ones (5-8 and 12-21), were isolated and their structures including absolute configurations were elucidated by extensive spectroscopic data and electronic circular dichroism (ECD) analyses. All of the isolates were tested for antioxidant and human cancer cell proliferation inhibitory activities. Twenty compounds showed comparable antioxidant activity to the positive controls, and three significantly inhibited the growth of three cancer cell lines HCT-116, A549, and MDA-MB-231 with IC50 values of 0.78-2.93 μM, which confirmed its health benefits.

Two new spiroketal derivatives with an unprecedented amino group, 2'-aminodechloromaldoxin (1) and 2'-aminodechlorogeodoxin (2), along with one known analogue dechloromaldoxin (3), were isolated from the plant endophytic fungus Pestalotiopsis flavidula. Their structures were elucidated on the basis of extensive spectroscopic analysis. The purification was cytotoxicity-guided which indicated the extract, fractions and compounds were evaluated in vitro for anti-proliferative activity against a panel of human cancer cell lines. The results showed compounds 1 and 2 with moderate cytotoxicity while 3 was inactive, which suggested -NH2 group might play a very important role for their cytotoxicity. This is the first study for P. flavidula and the first time to report the spiroketal derivatives as alkaloids from the Pestalotiopsis genus.

Five undescribed cycloartane triterpenoids, including two cycloartane trinor-triterpenoids, were isolated from a 70% ethanol extract of the whole plant of Actaea vaginata (Ranunculaceae), together with thirteen known cycloartane triterpenoids. Their structures were determined by spectroscopic techniques and quantum chemical calculations for intramolecular noncovalent interactions with reduced density gradient method. All compounds were evaluated for their anti-inflammatory effects by a lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production model in RAW264.7 macrophage cells, and some showed potent inhibitory effects with IC 50 values ranging from 5.0 to 24.4 μ M. Further mechanism studies showed that one compound dose-dependently suppressed LPS-induced NO production and pro-inflammatory cytokines secretion, and decreased the expression of iNOS, through inhibiting NF- κ B activation.

Phytochemical investigation on the twigs and leaves of Trichilia sinensis led to the isolation of two previously undescribed limonoids (i.e., trichiliasinenoids D and E, 1 and 2), two previously undescribed phenolic acids (3 and 4), and one previously undescribed natural phenolic acid dimer (5), together with 11 known compounds (6-16). Their structures were elucidated by extensive spectroscopic analysis (IR, UV, HRESIMS, 1D and 2D NMR) and chemical techniques. The potential anti-inflammatory activities of all the compounds were evaluated in lipopolysaccharide-stimulated RAW 264.7 cells. Among these isolates, compounds 1, 2, 6, and 11-13 expressed weak NO inhibition. The antibacterial activities of all the compounds against bacteria were also tested in vitro. Compound 16 exhibited moderate antibacterial activities against Escherichia Coli.

Eleven previously uncharacterized steroids, along with three analogs were isolated from Aglaia lawii leaves. Their structures were definitely characterized by the methods of NMR, MS, IR, ECD and X-ray crystallography study. Among these unreported compounds, 3-epi-dyscusin C, 3-epi-lansisterone E and (Z)-2α-hydroxyaglawone were C-21 pregnane steroids incorporating a highly oxygenated ring A, while others were Δ5-3β-hydroxy-7-ketosteroids bearing different ring D and C-17 aliphatic chains. All isolates were evaluated for nitric oxide (NO) inhibitory activities. 3-Epi-dyscusin C, 3-epi-lansisterone E, (Z)-2α-hydroxyaglawone and 17(20)E-dyscusin B showed significant anti-inflammatory activities with IC50 values of NO inhibition less than 10 μM (in the range from 4.47 ± 0.36 to 7.67 ± 0.46 μM).

Four previously undescribed steroids, identified as (3S,7S,8S,9S,10R,13S,14S,16S,17R,20S)-7α-methoxy-ergosta-5,24(28)-dien-3β,16β,20-triol (1), ergosta-5,24(28)-dien-3β,7α,16β-triol (2), ergosta-5,25-dien-3β,7α,16β,20-tetrol (3) and 7α,16β,24α-trihydroxy-varninasterol (4), as well as five known analogues (5–9), were isolated from the leaves and twigs of Dysoxylum pallens Hiern (Meliaceae). Their structures were elucidated based on extensive spectroscopic analysis such as HR-ESI-MS, 1D and 2D NMR, UV, and IR. The absolute configuration of compound 1 was determined by X-ray diffraction analysis. Selected compounds were evaluated for their cytotoxic activities. Compounds 1, 2, and 8 exhibited moderate cytotoxic activity against HL-60, Hela, and HepG2 tumor cell lines with IC50 ranged from 11.09 to 17.51 μM.

Trichiliasinenoids A–C (1–3), three new limonoids with an unprecedented C-29-C-7 connecting carbon skeleton formed by migration of C-7 from C-6 to C-29 of a mexicanolide-type limonoid precursor were isolated from the leaves and twigs of Trichilia sinensis. Their structures were assigned by spectroscopic analysis, and the absolute configurations were determined by X-ray crystallography (1) and ECD calculation (2 and 3). A possible biosynthetic pathway of 1 was also proposed. Compound 2 exhibited moderate cytotoxicity against HL-60 cells and weak cytotoxicity against SMMC-7721cells.

Two new prenylated acetophenone derivatives racemates, meliviticines A ( 1 ) and B ( 2 ) with unprecedented rearranged skeletons, were isolated from Melicope viticina . Subsequent chiral resolution led to the separation of two pairs of enantiomers, (±)-meliviticines A ( 1a / 1b ) and (±)-meliviticines B ( 2a / 2b ). Their structures including absolute configurations were elucidated by extensive spectroscopic data, electronic circular dichroism analysis, and X-ray crystallography. A plausible biosynthetic pathway of 1 and 2 , involving ring cleavage and rearrangement of the prenylated acetophenone backbone was proposed. All the isolates showed moderate antimicrobial activities with MIC values of 25–50 μ g/mL against several bacterial and fungal strains.

Three new arylalkenyl α,β-unsaturated δ-lactones, cryptobrachytones A–C (1–3), together with one known analogue kurzilactone (4), were isolated from the leaves and twigs of Cryptocarya brachythyrsa. Their structures were elucidated based on extensive spectroscopic data and electronic circular dichroism (ECD) analysis. All the isolates were evaluated in vitro for anti-proliferative activity against a panel of five human cancer cell lines and one human normal cell, respectively, and the results showed 1, 2 and 4 possessing significant selective cytotoxicity toward the human cancer cell lines with IC50 values from 5.41 to 15.43 μM. This is the first study for C. brachythyrsa.

Eight new prenylated coumarins (1a/1b, 2a/2b, and 3–6) including two pairs of enantiomers (1a/1b and 2a/2b), a new phenolic acid derivative, methyl (E)-3,4-bis(4-hydroxyphenyl)-4-oxobut-2-enoate (7), and 33 known compounds (8–40) were isolated from the stems of Toddalia asiatica. Their structures were established from spectroscopic data and by chemical methods. The absolute configurations of two pairs of enantiomers (1a/1b and 2a/2b) were determined by X-ray diffraction analysis together with ECD and specific optical rotation calculations. The inhibitory effects of selected compounds against phosphodiesterase-4 (PDE4) were evaluated, and compounds 12, 19, 21–23, 26, 34, and 35 exhibited PDE4 inhibition activities with IC50 values less than 10 μM.

Choosing a suitable solvent system for a counter-current chromatography separation presents a challenge for many researchers. In this study we introduce a quick method of separating a target compound from the bark of Zanthoxylum myriacanthum var. pubescens by counter-current chromatography. This method relies on the thin-layer chromatography based generally useful estimation of solvent systems. This paper will present how to quickly choose a suitable solvent system with a thin-layer chromatography based generally useful estimation of solvent systems working chart. O-Methyltembamide (1) was enriched by counter-current chromatography using n-hexane/ethyl acetate/methanol/water (6:4:6:4) as the solvent system. Further purification was achieved by high-performance liquid chromatography with purities of 98.2% from Z. myriacanthum var. pubescens bark. This article is protected by copyright. All rights reserved

Five new compounds, namely fimbricalyxoids A–D (1–4) and 13-O-methylfimbricalyx B (5), together with five known compounds (6–10) were isolated from the leaves and stems of Strophioblachia fimbricalyx. Fimbricalyxoid A (1), a cleistanthane diterpenoid, possesses a rare 3,20-oxybridge, while fimbricalyxoids C–D (3–4) are the first seco-ring-A pentanorditerpenoids. Their structures and absolute configuration were established based on NMR and MS data and ECD calculation (1). Compounds 1, 6, and 7 exhibited cytotoxicity against five human tumor cell lines with IC50 values in the range of 1.4–8.2 μM.

Two new vilasinin limonoids, walsuronoids DnE ( 1 n 2 ), along with three known compounds ( 3 n 5 ) were isolated and identified from the leaves ofn Walsura robusta . Their structures were established based on extensive spectroscopic analysis. Compoundsn 1 n 2 nshowed potent cytotoxic activity against HL-60, SMMC-7721, A-549, MCF-7, and SW480 cancer cell lines, with IC 50 nvalues ranging from 2.7 to 4.5nmM. The absolute configuration ofn 3 nwas determined to be (24 R , 25 S )-cycloartane-3b,24,25,26-tetrol for the first time by using X-ray diffraction analysis.

Twelve previously undescribed mexicanolide-type limonoids, including two pairs of isomers, together with seven known analogues were isolated from the twigs and leaves of Cipadessa baccifera. Their structures were determined by extensive spectroscopic methods and electronic circular dichroism (ECD) calculations. Structural variations mainly occurred at the attachment of C-3 and the carbon residues linked to C-17. 21-deoxo-23-oxofebrifugin A and 3-O-detigloyl-3-O-isobutyryl-21-deoxo-23-oxofebrifugin A are two rare naturally occurring mexicanolide-type limonoids bearing an α,β-unsaturated-γ-lactone motif at C-17. Moreover, cipaferen R is the first degraded tetranortriterpenoid derivative featuring an unique acetyl group at C-17. Some isolated compounds were evaluated for nematicidal, antifungal, cytotoxic (against five human cancer cell lines), and acetylcholinesterase inhibitory activities. No nematicidal and antifungal activities were observed, yet 3-O-detigloyl-3-O-isobutyrylfebrifugin A, febrifugin A, febrifugin, and khaysin T exhibited moderate cytotoxic activity against the tested cells with IC50 values ranging from 18.56 ± 0.27 to 38.00 ± 0.85 μM, and 3-O-detigloyl-3-O-isobutyrylfebrifugin A, granatumin E, khaysin T, and 2′S-cipadesin A showed moderate inhibitory activities against acetylcholinesterase (AChE) at 50 μM.

Eight previously undescribed diterpenoids, euphoroyleans A−H, including two cembranes, three ingenanes, two ent-atisanes, and one ent-kaurane, along with 22 known analogues were isolated from the whole plants of Euphorbia royleana. The structures of euphoroyleans A−H, including the absolute configurations, were elucidated by extensive spectroscopic analyses, chemical transformation, and single crystal X-ray diffractions. All the isolates were screened for their chemoreversal abilities on P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) cancer cell line HepG2/DOX, and eight compounds exhibited significant activities. Among them, ingol-3,7,12-triacetate-8-benzoate, the most active MDR modulator with no obvious cytotoxicity, could enhance the efficacy of anticancer drug DOX to ca. 105 folds at 10 μM, being stronger than the positive drug verapamil. Mechanistic study revealed that ingol-3,7,12-triacetate-8-benzoate could inhibit the transport activity of P-gp rather than its expression, and the possible recognition mechanism between compounds and P-gp was predicted by molecular docking.

Chemical investigation of Lansium domesticum has led to the isolation of two undescribed compounds, namely 17(20)E-dyscusin B (1) and 17(20)Z-dyscusin B (2), as well as three known ones (3 – 5). Structural elucidation was accomplished by the analysis of NMR, MS and IR data. Compounds 1 and 2 were a pair of Δ17(20) geometric isomers of pregnane steroids and showed the significant nitric oxide (NO) inhibitory activities.

Chemical investigation of the aerial parts of Mikania micrantha led to the isolation of eight sesquiterpenoids and ten diterpenoids, including five cadinane sesquiterpenoids (1−5), three bisabolene sesquiterpenoids (6 − 8), nine ent-kaurane diterpenoids (9–17), and an abietane diterpenoid (18). Among them, 1 − 3 are new and feature a rare lactone or furan ring derived from C-6 isopropyl group side chain. Compound 18 was isolated from genus Mikania for the first time, and was also the first example of abietane-type diterpenoids from this plant. Their structures were elucidated on the basis of extensive spectroscopic analyses (1D and 2D NMR, HRESIMS, and ECD). All compounds were examined for their inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 macrophage cells, and compound 18 exhibited pronounced inhibition on NO production (IC50 = 11.04 µM), being comparable to the positive control, quercetin (IC50 = 11.15 µM).

Four highly rearranged labdane-type diterpenoids, maximumins A–D (1–4) possessing different new carbon skeletons, together with a biosynthetically related known analog 5 were isolated from Amomum maximum. The structures of new compounds with absolute configurations were characterized by spectroscopic and computational approaches. The plausible biogenetic pathways for 1–4 were proposed. These compounds showed moderate to weak activities against nuclear factor kappa B (NF-κB).

Mulberry Diels-Alder-type adducts (MDAAs) are a group of structurally unique natural products biosynthetically derived from the intermolecular [4 + 2] cycloaddition of a dehydroprenylphenol and a chalcone. In the current study, ten MDAAs, including an undescribed one, inethermulberrofuran C, were isolated from the root bark of Morus alba. The anti-Alzheimer's disease (anti-AD) properties of these isolates were systematically screened for a series of potential targets (Aβ self-aggregation, tau aggregation, and ChEs) as well as the anti-neuroinflammatory and neuroprotective activities. Four compounds, mulberrofuran C, mulberrofuran K, mulberrofuran G, and isomulberrofuran G, turned out to be potent multi-targeted agents for AD. Among them, mulberrofuran K with a good blood-brain barrier (BBB) permeability (8.7 ± 0.3 × 10−6 cm/s) was selected as a promising candidate for further mechanism study in glutamate-induced HT22 cell model, which showed its neuroprotective ability on up-regulation of the glutathione (GSH) level and suppression of the reactive oxygen species (ROS) production.

Twelve compounds were isolated from the roots of Aglaia odorata. Their structures were established on the basis of NMR and MS data as rocaglaol (1), rocaglamide (2), eichlerialactone (3), sapelins A (4), isofouquierone (5), eichlerianic acid (6), shoreic acid (7), agladupol E (8), 3-epimeliantriol (9), cleomiscosins B (10), 2β,3β-dihydroxy-5α-pregnane-16-one (11) and β-D-glucopyranos-1-yl N-methylpyrrole-2-carboxylate (12). Among them, compounds 1 and 2 showed significant cytotoxicity against human cancer cell (HL-60, SMMC-7721, A-549, MCF-7 and SW480) with IC50 values of 0.007-0.095 μM, while compounds 3-5 and 10 and 11 showed moderate to no cytotoxicity (IC50 0.43 to values >40 μM). Compound 6 showed only weak cytotoxicity (IC50 6.87 to >40 μM) and its epmier 7 was completely inactivite (IC50>40 μM) in the assay. However, potent synergistic effect was observed when the molar ratio of 6 to 7 is between 4:1 and 1:1.

Four new diterpenoids, named aspidoptoids A&ndash, D (1&ndash, 4), together with two known analogues (5&ndash, 6) were isolated from Aspidopterys obcordata vine. Aspidoptoids A&ndash, B (1&ndash, 2) are the first examples of phenylethylene-bearing 20-nor-diterpenoids of which aspidoptoid B (2) possesses a rare 3,10-oxybridge. Their structures and absolute configuration were determined by extensive spectroscopic analyses (IR, HRESIMS, 1D and 2D NMR) and electronic circular dichroism (ECD) calculation. In addition, all the isolates were evaluated for their cytotoxic activities and inhibitory effects on the nitric oxide (NO) production.

Five selaginellin derivatives (1 and 3–6) including a new one, selaginellin T (1), and a new triarylbenzophenone analog, selagibenzophenone A (2), were isolated from the whole plants of Selaginella pulvinata. Their structures were determined by 1D- and 2D-NMR and HR-ESI-MS data. Selagibenzophenone A (2) is the first example of naturally occurring triarylbenzophenone. The results of the phosphodiesterase-4 (PDE4) inhibitory screening assays showed that compounds 1−6 exhibited potent activities with the IC50 values in the range of 1.04−9.35 μM.

Phytochemical investigation of Strychnos nitida has led to the isolation of three new racemic pyridocarbazole alkaloids, (±)-stritidas A-C (1–3) and three known monoterpenoid indole alkaloids (4–6). Compounds 2 and 3 represent the first examples of pyridocarbazole alkaloids featuring an N-2-hydroxyethyl moiety. Their structures were determined by combined spectroscopic data (MS, UV, IR and NMR) and chemical methods.