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Phytochemical studies on the leaves and twigs of Garcinia oligantha Merr. led to the isolation of twelve previously undescribed depsidone derivatives (oliganthdepsidones A-L, 1-12). Their structures were elucidated by extensive spectroscopic analysis including 1 H and 13 C NMR, HSQC, HMBC and NOESY along with HRESIMS. The structures of oliganthdepsidones G and J were finally determined using DFT-NMR chemical shift calculations and DP4+ methods. Cytotoxicity test in four human cancer cell lines indicated that oliganthdepsidone F had relatively strong cytotoxic effect against A375 (melanoma), A549 (lung cancer), HepG2 (liver cancer), and MCF-7 (breast cancer) cell lines with IC 50 of 18.71, 15.44, 10.92, and 15.90 μM, respectively. The dose- and time-dependent antiproliferative effects of oliganthdepsidone F on these cell lines were also observed by CCK-8 test. As determined by fluorescent microscopy and flow cytometry in these cell lines, oliganthdepsidone F could promote cell apoptosis, leading to the inhibition of cell proliferation. The results of wound healing assay and transwell assay showed that oliganthdepsidone F could inhibit the migration and invasion of A549 and MCF-7 cell lines in a concentration-dependent manner., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Bioassay-guided isolation of the stems of Garcinia paucinervis led to one new adamantane-type polycyclic polyprenylated acylphloroglucinols (PPAPs), (-)-garpauvinin A ( 1 ), and four known analogues ( 2-5 ). The structure and absolute configuration of 1 was established via spectroscopic techniques and ECD method. All the isolates displayed moderate antiproliferative activity against HL-60, PC-3 and Caco-2 human cancer cell lines with IC 50 values ranging from 0.81 to 19.92 μM, and exhibited low toxicity on WPMY-1 normal human cells, showing selectivity between normal and malignant prostate cells. The biosynthetic pathways of the isolated PPAPs were proposed.

In recent years, with sinomenine hydrochloride as the main ingredient, Qingfengteng had been formulated as various dosage forms for clinical treatment. Subsequent findings confirmed a variety of biological roles for sinomenine. Here, 15 H 2 S-donating sinomenine derivatives were synthesized. Target hybrids a11 displayed substantial cytotoxic effects on cancer cell lines, particularly against K562 cells, with an IC 50 value of 1.36 μM. In-depth studies demonstrated that a11 arrested cell cycle at G1 phase, induced apoptosis via both morphological changes in nucleus and membrane potential collapse in mitochondria. These results indicated a11 exerted an antiproliferative effect through apoptosis induction via mitochondrial pathway.

Genome editing tools based on SpCas9 and FnCpf1 have facilitated strain improvements for natural product production and novel drug discovery in Streptomyces . However, due to high toxicity, their editing requires high DNA transformation efficiency, which is unavailable in most streptomycetes. The transformation efficiency of an all-in-one editing tool based on miniature Cas nuclease AsCas12f1 was significantly higher than those of SpCas9 and FnCpf1 in tested streptomycetes, which is due to its small size and weak DNA cleavage activity. Using this tool, in Streptomyces coelicolor , we achieved 100% efficiency for single gene or gene cluster deletion and 46.7 and 40% efficiency for simultaneous deletion of two genes and two gene clusters, respectively. AsCas12f1 was successfully extended to Streptomyces hygroscopicus SIPI-054 for efficient genome editing, in which SpCas9/FnCpf1 does not work well. Collectively, this work offers a low-toxicity, high-efficiency genome editing tool for streptomycetes, particularly those with low DNA transformation efficiency.

Two new aporphine alkaloids, 6a R -2'-(3-oxobutenyl)-thaliadin ( 1 ) and N -methylthalisopynine ( 2 ), along with ten known analogs ( 3 - 12 ), were isolated from the roots of Thalictrum omeiense W. T. Wang et S. H. Wang. Their structures were determined by extensive spectroscopic and X-ray crystallographic analyses. Compounds 1 - 7 and 9 - 12 were tested for their antiproliferative effects in vitro against two human cancer cell lines (A549 and MCF-7). Among them, compounds 1 , 3, and 7 exhibited moderate inhibitory activity against the tested cell lines with IC 50 values ranging from 23.73 to 34.97 μM.

Streptomycetes have a strong ability to produce a vast array of bioactive natural products (NPs) widely used in agriculture and veterinary/human medicine. The recently developed CRISPR/Cas9-based genome editing tools have greatly facilitated strain improvement for target NP overproduction as well as novel NP discovery in Streptomyces . However, CRISPR/Cas9 shows high toxicity to the host, limiting its application in many Streptomyces strains with a low DNA transformation efficiency. In this study, we developed a low-toxicity CRISPR/Cas9 D10A nickase (nCas9)-based genome editing tool in the model strain Streptomyces coelicolor M145. We showed that in the presence of both targeting sgRNA and Cas proteins, utilization of nCas9 instead of Cas9 significantly reduced the toxicity to the host and greatly enhanced cell survival. Using this tool, we achieved deletion of single genes and gene clusters with efficiencies of 87-100 and 63-87%, and simultaneous deletion of two genes or gene clusters with efficiencies of 47 and 43%, respectively. The editing efficiency of nCas9 is comparable to that of the Cas9-mediated editing tool. Finally, the nCas9-based editing tool was successfully applied for genome editing in the industrial rapamycin-producing strain Streptomyces rapamycinicus , in which CRISPR/Cas9 cannot work well. We achieved the deletion of three tested genes with an efficiency of 27.2-30%. Collectively, the CRISPR/nCas9-based editing tool offers a convenient and efficient genetic modification system for the engineering of streptomycetes, particularly those with low DNA transformation efficiency.

In order to find potential agents for treating cancer disease in naturally occurring compounds, we conducted a systematic phytochemical investigation on the endemic species of Garcinia nujiangensis. Three new biphenyl derivatives (1-3) and one new polycyclic polyprenylated benzophenone (4), together with four known benzophenone analogues (5-8), have been isolated from the CH 2 Cl 2 extract of the twigs and leaves of G. nujiangensis. Their structures were determined by detailed spectroscopic analyses and comparison with structurally related known analogues. Experimental and calculated ECD method was used to determine the absolute configuration of 1 and 4. Moreover, compounds 5-7 were isolated for the first time from this species. The cytotoxicities of the new compounds were evaluated using HL-60, HepG2, and A549 human cancer cell lines. Compound 4 showed more significant antiproliferative effects against HepG2 cells with an IC 50 value of 11.38 ± 0.79 μM than that of three biphenyl derivatives. The morphological features of apoptosis were evaluated in 4-treated HepG2 cells. Compound 4 effectively prevented the cell cycle progression of HepG2 cells in G 2 phase. Additionally, western blot analysis indicated that treatment of 4 on HepG2 cells led to decreased expression of anti-apoptotic Bcl-2 and pro-Caspase-3, and increased protein expression of both pro-apoptotic Bax and cleaved PARP with reference to β-actin. Overall, our results suggested that the active polycyclic polyprenylated benzophenone derivatives in the twigs and leaves of G. nujiangensis can be used as a valuable source of bioactive compounds for the pharmaceutical industry., Competing Interests: Declaration of Competing Interest No potential conflict of interest was reported by the authors., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The present study aimed to explore the chemical constituents from the stems and leaves of Cephalotaxus fortunei. Seven lignans were isolated from the 75% ethanol extract of C. fortunei by various chromatographic methods, including silica gel, ODS column chromatography, and HPLC. The structures of the isolated compounds were elucidated according to physicochemical properties and spectral data. Compound 1 is a new lignan named cephalignan A. The known compounds were identified as 8-hydroxy-conidendrine(2), isolariciresinol(3), leptolepisol D(4), diarctigenin(5), dihydrodehydrodiconiferyl alcohol 9'-O-β-D-glucopyranoside(6), and dihydrodehydrodiconiferyl alcohol 4-O-β-D-glucopyranoside(7). Compounds 2 and 5 were isolated from the Cephalotaxus plant for the first time.

Two new iridoid glycosides, named 3'- O -benzoyl-dolichocymboside D ( 1 ) and dolichocymboside E ( 2 ), along with ten known glycosides ( 3-12 ), were isolated from the ethanol extract of the whole plants of Odontites vulgaris Moench. The structures of the isolated compounds were elucidated by 1D and 2D NMR and HR-ESI-MS spectra and by comparison with those reported in the literature. This is the first report on compounds 11 and 12 isolated from the family Scrophulariaceae, and compounds 8-10 were isolated from the genus Odontites .

Stilbenes (based on the 1,2-diphenylethylene skeleton) are a class of plant polyphenols with rich structural and bioactive diversity. Twenty-six stilbenes, including five undescribed compounds (7,8-dioxy-4,3',5'-trihydroxystilbene, trans-13'-methoxygnetin H, suffruticosol E, paestibenetrimerols A and B), were isolated from the seedcases of Paeonia suffruticosa Andrews. Their structures were elucidated by spectroscopic analyses and comparison with previously reported data. The absolute configurations of trans-13'-methoxygnetin H, suffruticosol E, paestibenetrimerols A and B were assigned from their respective electronic circular dichroism (ECD) spectra. Additionally, the structures of known compounds suffruticosols A, B and rockiol B were revised and the absolute configurations of them, and along with (+)-davidiol A, were also further determined by ECD. The isolated compounds, trans-gnetin H, cis-gnetin H and suffruticosol E, were found to have potent cytotoxicity against the DU-145 and MDA-MB-231 cell lines with IC 50 values of 4.89-8.61 μM. The preliminary antitumor structure-activity relationship of these stilbenes is discussed as well., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

19 compounds, including seven previously undescribed alkaloids ((-)-macleayin K (1), (+)-macleayin K (2), macleayin M (3), macleayin N (4), macleayin L (5), macleayin O (6), oxohydrastinine A (7), one new natural product (8), and 11 known compounds, were isolated from the fruit pods of Macleaya microcarpa. Their structures were defined based on NMR, HRESIMS, and electronic circular dichroism (ECD) data. A network pharmacology approach combined with molecular docking and in vitro validation was performed to determine the bioactivity, key targets of the 19 compounds against breast cancer (BC) and cervical cancer (CC). EGFR and PIK3CA could become potential therapeutic targets based a network pharmacology. Moreover, molecular docking suggested that the 19 compounds combined well with EGFR and PIK3CA, respectively. Their cytotoxicity of selected compounds was tested against the MCF-7 and HeLa cells, and the preliminary structure-activity relationship is discussed. Compounds 1 (IC 50 : 6.00 μM) and 2 (IC 50 : 6.82 μM) exhibited strong inhibitory activity against the HeLa cells and are worthy of further study., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Two pairs of unprecedented β-carboline-phenylpropanoid heterogeneous alkaloids, (±)-pheharmines A-B (1-4), characterized by a morpholino[4,3,2- hi ]β-carboline core with two chiral centers, were isolated from the roots of Peganum harmala . The structures, including their absolute configurations, were identified using spectroscopic analyses and electronic circular dichroism (ECD) calculations. The biosynthetic hypothesis for the formation of pheharmines A-B was proposed. Compounds 1-4 exhibited moderate cytotoxic activities against HL-60 cell lines.

Frankincense (FRA), the oily resin consisting of essential oils, boswellic acids (BAs) and polysaccharides, has been used to improve the blood circulation and relieve pain against carbuncles. According to the theory of traditional Chinese medicine, vinegar processed frankincense (VPF) can increase the effects of promoting blood circulation and relieving pain. Existing studies have carried out much on BAs and essential oils. However, the comparative analysis of polysaccharides from FRA and VPF has not been reported. In this paper, two polysaccharides were isolated and purified from FRA and the other two were from VPF, and their structures and physicochemical properties were analyzed. The immunological and anticoagulatant activities of the four polysaccharides were tested in RAW 264.7 cell and Sprague-Dawley rats, respectively. The polysaccharides purified from VPF showed better immunological and anticoagulatant activities than those in FRA. Therefore, polysaccharides may be one of the active substances for the synergistic effect of VPF., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Twenty-two cephalotaxine-type and ten homoerythrina-type alkaloids, including seven previously undescribed ones, were isolated from the twigs and leaves and the seed kernels of Cephalotaxus fortunei . Their structures were established by spectroscopic analysis, single crystal X-ray diffraction, and ECD calculation methods. Cephalofortunine A β- N -oxide (1) is the first nitrogen-oxidized homoerythrina-type alkaloid. The isolated compounds were evaluated for their in vitro antiproliferative effects against two human leukemia cell lines (THP-1 and K562). All compounds showed different levels of antiproliferation in THP-1 and K562 cells with GI 50 values of 0.24-29.55 μM. Hainanensine (31) was the most active against two cancer cell lines with GI 50 values of 0.24 ± 0.07, and 0.29 ± 0.01 μM, respectively.

The chemical constituents from the roots of Thalictrum cultratum and T. baicalense were investigated. By various isolation methods, such as silica gel, aluminium oxide, ODS, and Sephadex LH-20 column chromatographies, and semi-preparative HPLC, 11 simple isoquinoline alkaloids were isolated from the ethanol extract of the roots of these two plants, including a new compound, named dehydrothalflavine(1), and ten known ones(2-11): N-methylcorydaline(2), N-methylthalidaldine(3), thaliflavine(4), oxyhydrastinine(5), noroxyhydrastinine(6), dimethoxyisoquinolone(7), thalactamine(8), dehydronoroxyhydrastinine(9), 6,7-dimethoxy-2-methyl-1,2,3,4-tetrahydroisoquinoline(10), and isopicnarrhine(11). Their structures were elucidated on the basis of HR-ESI-MS and 1 D and 2 D NMR techniques. Compound 1 was a new isoquinoline alkaloid. Compound 11 was obtained from Tha-lictrum plant for the first time. All compounds did not show cytotoxic activities against HL-60, U937, HCT116, Caco-2, and HepG2 cancer cell lines.

Six alkaloids peharmalines F-K, along with 14 known ones, were isolated from the aerial part of Peganum harmala L.. The structures of the isolated compounds were determined based on their HR-ESI-MS data, extensive NMR spectroscopic analyses, and ECD calculations. 3-(4-Hydroxyphenyl)quinoline exhibited potent antiproliferative activity against the HepG-2 cell lines with an IC 50 value of 3.05 μM. Norharmane displayed a moderate inhibition against A549 and HepG-2 cells with IC 50 values of 16.45 μM and 17.27 μM, respectively., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Eight cephalotaxine-type alkaloids (1-8), including two new compounds cephafortunines A and B (1-2), were isolated from the branches and leaves of Cephalotaxus fortunei var. alpina. Their structures were identified by a series of spectroscopic methods (MS, UV, IR, 1D, and 2D NMR) and comparison with the reported data of known analogs. The absolute configurations of 1 and 2 were determined by electronic circular dichroism (ECD) calculations. 1-8 were evaluated for their in vitro antiproliferation effects against two human leukemia cell lines (U937 and HL-60). All compounds showed different levels of antiproliferation effects against U937 cells with GI 50 values of 4.21-23.70 μM. 4 and 5 were the most active against U937 cells with GI 50 values of 4.21 and 6.58 μM and against HL-60 cells with GI 50 values of 6.66 and 6.70 μM, respectively. 4 and 5 arrested HL-60 cell cycle in G0/G1 phase., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Six new tirucallane-type triterpenoids (1-6), along with ten known triterpenoids, were isolated from methylene chloride extract of the resin of Boswellia carterii Birdw. By the application of the comprehensive spectroscopic data, the structures of the compounds were clarified. The experimental electronic circular dichroism spectra were compared with those calculated, which allowed to assign the absolute configurations. Compounds 5 and 6 possesed a 2, 3-seco tirucallane-type triterpenoid skeleton, which were first reported. Their inhibitory activity against NO formation in LPS-activated BV-2 cells were evaluated. Compound 9 showed appreciable inhibitory effect, with an IC 50 value of 7.58 ± 0.87 μmol·L -1 ., (Copyright © 2021 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.)

Baicalensines A ( 1 ) and B ( 2 ) were isolated from the roots of Thalictrum baicalense and structurally characterized using spectroscopic data, 13 C NMR calculations, and the CASE algorithm. Compound 1 , representing a new class of alkaloid dimers, contains berberine conjugated to a ring-opened isoquinoline. Compound 2 is the first reported natural benzylisoquinoline bearing a formyl group at C-3. Plausible biosynthetic pathways are proposed. Compound 1 exerted moderate cytotoxicity against the Caco-2 and HL-60 cell lines.

Two nonbiaryl axially chiral β-carboline-quinazoline dimers, pegaharmols A ( 1 ) and B ( 2 ), were isolated from the roots of Peganum harmala . Their planar structures were elucidated by the spectroscopic methods of high-resolution mass spectrometry and 1D and 2D nuclear magnetic resonance (NMR). The stereochemistry was established by a comparison between the experimental data of NMR and electronic circular dichroism and the computed data by quantum mechanical calculations. It is discovered for the first time that the β-carboline at the C-8 position is bonded to the vasicine at the C-9 position. 1 exhibited moderate cytotoxic activity against HL-60 and A549 cell lines.

A new xanthyletin-type coumarin, neopeucedalactone ( 1 ), was isolated from the roots of Peucedanum praeruptorum Dunn. Its chemical structure was elucidated based on extensive spectroscopic interpretation. The absolute configurations of xanthyletin-type coumarin were determined by comparing experimental and calculated ECD spectra for the first time. Compound 1 exhibited moderate cell growth inhibitory activities in vitro against human leukemic HL-60, THP-1 cell lines, and human prostate cancer PC-3 cell lines, with IC 50 values of 9.97, 27.80, and 48.68 µM, respectively. [Formula: see text].

Inspired by the intriguing structures and bioactivities of polyprenylated xanthones, ten previously undescribed polyprenylated xanthones, nujiangxanthones G-P (1-10), and fifteen known ones (11-25) were isolated from the twigs and leaves of Garcinia nujiangensis. The structures of these compounds were established on the basis of spectroscopic data as well as comparison with the literature. Most of the isolates showed potent cytotoxicity against selected cancer cells. Compound 8 showed the highest effects against MDA-MB-231 and A549 cell lines with IC 50 values of 4.12 and 2.67 μM and 16 demonstrated the most potent activity against MCF-7 cell line with an IC 50 value of 3.36 μM., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Two new lignanamides, majusamides A and B (1 and 2), and two new alkaloids, chelidoniumine (3) and tetrahydrocoptisine N-oxide (4), together with six known hydroxycinnamic acid amides (HCCA) were isolated from the 75% ethanol extract of Chelidonium majus through the silica gel, Sephadex LH-20, MCI, ODS column chromatography, and semi-HPLC. Their structures were determined on the basis of spectroscopic data and physico-chemical methods. The absolute configurations of 1-3 were determined by electronic circular dichroism (ECD) calculations. The anti-inflammatory activities of all the isolates on the NO production in lipopolysaccharide (LPS)-induced macrophages were evaluated. Compounds 7 and 9 exhibited moderate inhibitory activity with IC 50 values of 25.3 ± 0.5 and 23.5 ± 1.7 μM, respectively., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A new fumiquinazoline-type alkaloid 2-methyl-versiquinazoline C (1), together with six known compounds (2-7), was isolated from Aspergillus flavipes PJ03-11 using OSMAC method. Their structures were elucidated on the basis of extensive spectroscopic analysis, and the absolute configuration of compound 1 was determined by the experimental and calculated ECD data. In addition, the cytotoxic activities against three human cancer cell lines (HL-60, THP-1, and PC-3) were evaluated.

Seven new drimane-type sesquiterpenoids, namely the sporulositols A - D ( 1 - 4 ), 6-hydroxydiaporol ( 5 ), seco -sporulositol ( 6 ) and sporuloside ( 7 ) were isolated from the ethyl acetate extract of fermentation broth for a marine-derived fungus Paraconiothyrium sporulosum YK-03. Their structures were elucidated by analysis of extensive spectroscopic data, and the absolute configurations were established by crystal X-ray diffraction analysis and comparisons of circular dichroism data. Among them, sporulositols A - E ( 1 - 4 ) and seco -sporulositol ( 6 ) represent the first five examples of a unique class of drimanic mannitol derivatives, while compounds 6 and 7 may represent two new series of natural drimanes, possessing an aromatic ring with a rare 4,5-secodrimanic skeleton and an unusual CH 3 -15 rearranged drimanic α-D-glucopyranside, respectively. Furthermore, the origin of mannitol moiety was investigated by reliable HPLC and NMR analyses.

Bioassay-guided fractionation of the dichloromethane-soluble portion of the stems of Garcinia paucinervis led to the isolation of eight new xanthones, including three pairs of enantiomers, (+) and (-) paucinervins L-N (1a-3a, and 1b-3b), one optically pure compound, (-) paucinervin O (4), and one new analogue, paucinervin P (5), as well as thirteen known xanthones (6-18). Their structures were established by detailed analysis of extensive spectroscopic data. The absolute configurations of 1-4 were confirmed by ECD calculations. All the isolates 1-18 displayed antiproliferative effect against HL-60 with IC 50 values ranging from 0.87 to 29.14 μM, of which compound 5 was the most active. Compounds 6, and 14 exhibited potential inhibitory activity against PC-3 cells, while compounds 5-7, 14, and 16-17 displayed cytotoxic potency against Caco-2 cells. A preliminary structure-activity relationship was also discussed., (Copyright © 2018 Elsevier B.V. All rights reserved.)

With bioassay- and chemistry-guided fractionation, seven new caged prenylxanthones including two scalemic mixtures, epiisobractatin (1), 13-hydroxyisobractatin (2), 13-hydroxyepiisobractatin (3), 8-methoxy-8,8a-dihydrobractatin (4), 8-ethoxy-8,8a-dihydrobractatin (5), garcibracteatone (6), and 8-methoxy-8,8a-dihydroneobractiatin (7), and the eight known compounds 8-15 were isolated from the leaves of Garcinia bracteata. The structures were unambiguously elucidated through analysis of spectroscopic data. The 2D structures and relative configurations of 1 and 5 were confirmed by X-ray crystallographic analysis. The separation of the enantiomers of 1-5 was accomplished by chiral-phase HPLC. The absolute configurations of the enantiomers of 1 and 5 were assigned by comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. The absolute configurations of the related compounds were determined via comparisons of their ECD data with those of the enantiomers of 1 and 5, respectively. Notably, compound 7, with a neo caged skeleton, is the first representative of a novel type of caged xanthone lacking a Δ 8(8a) double bond. The isolated compounds exhibited significant cell growth inhibitory activities in vitro against human leukemic HL-60 and K562 cell lines, with GI 50 values ranging from 0.2 to 8.8 μM. A preliminary structure-activity relationship is discussed.

One pair of new cyclopentaisochromenone derivatives, (+)-(S)-6-hydroxy-1,8-dimethoxy-3a-methyl-3,3a-dihydrocyclopenta[c]isochromene-2,5-dione (1a) and (-)-(R)-6-hydroxy-1,8-dimethoxy-3a-methyl-3,3a-dihydrocyclopenta[c]isochromene-2,5-dione (1b), together with seven known analog 2‒8, were isolated from a rice solid culture of the endophytic fungus Alternaria sp. TNXY-P-1, obtained from fresh leaf of Arisaema heterophyllum. Their structures were elucidated on the basis of detailed 1D, 2D NMR, and HRESIMS analysis. Among them, compounds 1a and 1b were enantiomers separated from 1 by chiral HPLC. The absolute configurations of 1a and 1b were assigned by quantum chemical calculations of the electronic circular dichroic spectra. All isolated compounds were evaluated for cytotoxic activities. Interestingly, enantiomers (+)-1a and (-)-1b showed distinct selective antitumor activities against HL-60 cell lines with IC 50 values of >200, 75.3 μM, respectively.

Five pairs of new 2-oxoindole alkaloids, (±)-peganumalines A-E (1-5), and a new indole alkaloid, peganumaline F (6), along with two known analogues, were isolated from the seeds of Peganum harmala. Their structures and absolute configurations were elucidated through spectroscopic analyses and quantum chemistry calculations. Notably, (±)-peganumalines A (1) represent a pair of rare 2-oxoindole dimeric alkaloid enantiomer with the hitherto unknown carbon skeleton. All isolates were tested for antiproliferative and antibacterial activities., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Three new diterpenoids, ebractenoids O~Q (1-3), and a new phenolic glucoside, γ-pyrone-3-O-β-d-(6-galloyl)-glucopyranoside (4), together with 6 known compounds, were isolated from the 95% ethanol extract of the roots of Euphorbia ebracteolata, and their structures were elucidated on the basis of spectroscopic data. The absolute configurations of 1-3 were determined by electronic circular dichroism (ECD) calculations. The inhibitory effects of all the isolates with exception of compounds 8 and 10 on the NO production in lipopolysaccharide (LPS)-induced macrophages were evaluated. All of them exhibited significant inhibitory activity., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Seventeen quinazoline alkaloids and derivatives, containing two pairs of new epimers, named as (S)- and (R)-1-(2-aminobenzyl)-3-hydroxypyrrolidin-2-one β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranoside (1, 2), (S)- and (R)-vasicinone β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranoside (3, 4), and a new enantiomer (12b), together with six known ones (5-8, 10, and 12a), and three pairs of known enantiomers (9, 11, and 13), were isolated from the ethanol extracts of the seeds of Peganum harmala L.. Their structures including the absolute configuration were elucidated by using 1D and 2D NMR, and ECD calculation approaches. The cytotoxic activities of all isolated compounds were evaluated. 11 showed moderate cytotoxicity against PC-3 cells with an IC 50 value of 15.41 μM., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Inspired by the intriguing structures and bioactivities of dimeric alkaloids, 11 new thalifaberine-type aporphine-benzylisoquinoline alkaloids, thalicultratines A-K, a tetrahydroprotoberberine-aporphine alkaloid, thalicultratine L, and five known ones were isolated from the roots of Thalictrum cultratum. Their structures were defined on the basis of NMR and HRESIMS data. The antiproliferative activities of compounds 1-17 were evaluated against human leukemia HL-60 and prostate cancer PC-3 cells. Most alkaloids showed potent cytotoxicity against selected cancer cells. Preliminary SARs are discussed. The most active new compound (3), with an IC 50 value of 1.06 μM against HL-60 cells, was selected for mechanism of action studies. The results revealed that compound 3 induced apoptosis and arrested the HL-60 cell cycle at the S phase with the loss of mitochondria membrane potential. The nuclear morphological Hoechst 33258 staining assay was also carried out, and the results confirmed apoptosis.

Four new α-pyrone derivatives phomones C-F (1-4) together with four known compounds (5-8) were isolated from the endophytic fungus Phoma sp. YN02-P-3. Compound 1 is the first example of 6-α,β-unsaturated ester-2-pyrone dimers via intermolecular symmetrical [2+2] cycloaddition. The chemical structures of these compounds were determined from spectroscopic data (1D/2D NMR, MS and IR). The acetylated product (9) of 1 along with compounds 1-8 were then tested for their cytotoxicity against HL-60, PC-3 and HCT-116 cell lines. Compounds 2, 3, 5 and 9 with acetyl groups showed significant inhibitory activities against the three cell lines with IC 50 values in the range 0.52-9.85μM. while compounds 1, 4 and 6-8 that possess no acetyl group showed no inhibitory activity (IC 50 >50μM), indicating that the acetyl group at 10- or 12- are essential for their cytotoxic activities. The structure-activity relationships of these phomones were also reported., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Two new d-threitol orsellinates (1-2) were isolated from the EtOAc extract of a sea mud-derived fungus, Ascotricha sp. ZJ-M-5, cultured in Czapek Dox broth. These two compounds featured in the symmetrical substitution of orsellinic acid or acetic acid, which was established on the basis of 1D and 2D NMR experiments. The characteristic optical rotations enabled the assignment of the absolute configuration.

Neobraclactones A-C (1-3), featuring an unprecedented further rearranged prenylxanthone skeleton with a unique octahydro-2H-1,3-dioxacyclopenta[c,d]inden-2-one scaffold, along with their biosynthesis-related known compound neobractatin (4), were isolated from the leaves of Garcinia bracteata. Their structures with absolute configurations were determined by extensive analyses of spectroscopic data and ECD calculations. Compounds 1 and 2 showed significant growth inhibition activities against the human leukaemia HL-60 and K562 cell lines with GI 50 values from 0.40 to 0.86 μM.

Two new amide compounds, mariamides A and B (1-2), were obtained together with fourteen known compounds from the seeds of milk thistle (Silybum marianum). Their structures were established on the basis of extensive 1D and 2D NMR analyses, as well as HR-ESI-MS data. Most of the compounds showed significant antioxidant activities than positive control in ABTS and FRAP assays. However, only amide compounds 1-4 showed moderate DPPH radical scavenging activity and compounds 7 and 16 showed the most potent activity against DPPH. Most of the compounds showed moderate to stronger α-glucosidase inhibitory activities. Nevertheless, only flavonoids showed strong PTP1B inhibitory activities. These results indicate a use of milk thistle seed extracts as promising antioxidant and antidiabetic agents., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Three new (1-3) and one known (4) bioactive terpenoids were isolated from the seeds of Silybum marianum based on the investigation to get new NO inhibitors. Their structures were determined by extensive NMR (1D and 2D NMR) and MS spectroscopic data, and the absolute configurations were identified by experimental and calculated ECD spectra. The NO inhibitory activities in murine microglial BV-2 cells and interactions with iNOS protein by molecular docking were evaluated for all compounds. The results showed that these compounds had potent NO inhibitory effects., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

1. Butyrolactone I (BL-I), one of the major secondary metabolites of fungus Aspergillus terreus, is a selective cdc2 kinase inhibitor. In the present study, the metabolism of BL-I in male Wistar rats was investigated by characterizing metabolites excreted into feces. 2. Following an oral dose of 40 mg/kg BL-I, 10 phase I metabolites were isolated from the feces of rats, and their structures were identified on the basis of a range of spectroscopic data and ICD analysis. These metabolites were fully characterized as butyrolactone VI (M1), aspernolide E (M2), 7''S-hydroxy-9''-ene-butyrolactone I (M3), 7''R-hydroxy-9''-ene-butyrolactone I (M4), 7″S, 8″R-dihydroxy-aspernolide E (M5), 7″R, 8″S-dihydroxy-aspernolide E (M6), 7″R-acetyl-8″S-hydroxy-aspernolide E (M7), 7″S-acetyl-8″R-hydroxy-aspernolide E (M8), 7″R-methoxy-8″S-hydroxy-aspernolide E (M9), butyrolactone V (M10), respectively. It is the first time to describe the metabolites of BL-I in vivo, and metabolites M3 to M9 are new compounds. 3. BL-I and metabolites M2 to M10 were evaluated for their antimicrobial activity and in vitro antiproliferative activities. Only M-3 and M-4 showed inhibitory effect against staphylococcus aureus both with MIC of 125 μg/ml. BL-I and metabolites M-4 and M-5 exhibited potent cancer cell growth inhibitory activities against HL-60 (human leukemia) cell lines with the IC 50 values of 13.2, 28.8 and 35.7 μM, respectively. 4. On the basis of metabolites profile, a possible metabolism pathway for BL-I in rats has been proposed. This is the first systematic study on the phase I metabolites of BL-I.

Investigation of the alkaloids from Peganum harmala seeds yielded two pairs of unique racemic pyrroloindole alkaloids, (±)-peganines A-B (1-2); two rare thiazole derivatives, peganumals A-B (3-4); six new β-carboline alkaloids, pegaharmines F-K (5-10); and 12 known analogues. Their structures, including stereochemistry, were elucidated through spectroscopic analyses, quantum chemistry calculations, and single-crystal X-ray diffraction. Notably, the incorporation of pyrrole and indole moieties in peganines A-B, thiazole fragments in peganumals A-B, and a C-1 α,β-unsaturated ester motif in pegaharmine F (5) are all rare, and their presence in the genus Peganum were demonstrated for the first time. All isolates were tested for antiproliferative activities against the HL-60, PC-3, and SGC-7901 cancer cell lines, and compounds 9, 11, 12, and 13 exhibited moderate cytotoxicity against HL-60 cancer cell lines with IC 50 values in the range of 4.36-9.25 μM.

A new sesquiterpene lactone glycoside (1) and a new quinic acid methyl ester (2) were isolated from Patrinia villosa, together with another two known compounds chlorogenic acid n-butyl ester (3), 3, 4-di-O-caffeoylquinic acid methyl ester (4). Their structures were established using 1D/2D-NMR spectroscopy, mass spectrometry, and comparing with spectroscopic data reported in the literature.

In this study, we screened 17 medicinal plants for binding activity to G-quadruplex d(TTGGGTT)4 by (1)H NMR spectroscopy and found that the crude extract of Peganum harmala L. seeds showed the most potential binding activity. Subsequently, (1)H NMR- and bioassay-guided isolation of the extract of P. harmala L. was performed to obtain four pairs of partially racemized β-carboline alkaloids, pegaharmines A-D (1-4). Their structures and absolute configurations were determined by extensive NMR analyses, X-ray crystallography, ECD calculations, and CD exciton chirality approaches. Interestingly, pegaharmine D (4), which showed the strongest G-quadruplex interaction, exhibited significant cytotoxic activity against three cancer cell lines. This work contributed a practical strategy for the discovery of novel G-quadruplex ligands from natural products and provided potential insights for using β-carboline alkaloids as anticancer lead compounds specifically targeting G-quadruplexes.

The first series of nitric oxide donating derivatives of evodiamine were designed and prepared. NO releasing ability of all target derivatives was evaluated in BGC-823, Bel-7402 and L-02 cells. The cytotoxicity was evaluated against three human tumor cell lines (Bel-7402, A549 and BGC-823) and normal human liver cells L-02. The nitrate derivatives 11a and 11b only exhibited moderate activity and furoxan-based derivatives 13a-c, 14a and 14b showed promising activity. 13c showed good cytotoxic selectivity between tumor and normal liver cells and was further investigated for its apoptotic properties on human hepatocarcinoma Bel-7402 cells. The molecular mode of action revealed that 13c caused cell-cycle arrest at S phase and induced apoptosis in Bel-7402 cells through mitochondria-related caspase-dependent pathways., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Investigation of the roots of Flemingia philippinensis resulted in the isolation of two new chalcones, flemiphilippinones B (1) and C (2), and one new pterocarpoid, demethylwedelolactone-11-methyl ether (3), together with 12 known compounds (4-15). The antiproliferative activity against PC-3 cells was evaluated and most compounds showed cytotoxicity, among which, compound 2 exhibited GI50 value of 14.12μM. The antiproliferative activity of 2 against Bel-7402 and CaEs-17 cells was also measured, with GI50 values of 1.91 and 2.58μM, respectively. Intensive mechanism study showed that 2 caused cell-cycle arrest at S/G2 phase and induced apoptosis in Bel-7402 cells through mitochondria-related pathway., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Two novel rare chloro-containing benzylisoquinoline alkaloids, thalfoliolosumines A (1) and B (2), along with eight known isoquinoline alkaloids (3-10) were isolated from the whole plant of Thalictrum foliolosum. The structures of these compounds were elucidated by spectral analyses, including 1D and 2D NMR (COSY, HSQC, HMBC and NOESY) experiments. The antiproliferative effects of all the isolated compounds were evaluated by MTT method against MCF-7, PC-3, and U937 cells, and trypan blue method against HL-60 cells. New compounds 1 and 2 exhibited moderate in vitro antiproliferative activity against MCF-7, PC-3, and HL-60 cells, and good inhibitory effects against U937 cells with IC50 values of 7.50 and 6.97 μM, respectively. Compounds 7 and 10 showed the strongest in vitro antiproliferative with IC50 values of 0.93 and 1.69 μM against HL-60 cell line. The antioxidant properties were also measured, bisbenzyltetrahydroisoquinoline alkaloids 3-6 showed the strongest antioxidant activities in ABTS assay.

Three new phenylnaphthalene-type lignans, vitexnegheteroins E-G (1-3), and a new polyoxygenated ursane-type triterpene, vitexnegheteroin H (9), were isolated from the seeds of Vitex negundo var. heterophylla, together with ten known compounds. Their structures were established on the basis of extensive 1D and 2D NMR experiments, as well as their mass spectroscopic data. The absolute configurations of compounds 1 and 2 were determined by comparing their experimental ECD spectra with that calculated by the time-dependent density functional theory (TDDFT) method. The isolates were evaluated for their cytotoxicities against three human cancer cell lines, inhibitory activities on lipopolysaccharide-induced NO production in murine microglial BV-2 cells, and antioxidant activities for ABTS radical scavenging., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Three new xanthones, paucinervins H-J (1-3), as well as eleven known compounds (4-14), were isolated from the leaves of Garcinia paucinervis. The structures of the new compounds (1-3) were elucidated by 1D, 2D NMR spectra and HR ESIMS. In vitro antiproliferative activity against human promyelocytic leukemia HL-60 cells was tested, among which, compounds 2, 5, 6 and 7 exhibited strong growth inhibitory effects with GI50 values ranging from 1.30 to 9.08 μM, respectively. Preliminary SARs were also discussed.

Ten new cassane-type diterpenoids, caesalbonducins D-F (1-3), 6-deacetoxybonducellpin B (4), 3-acetoxy-α-caesalpin (5), 2(3)-en-α-caesalpin (6), 1α-hydroxycaesalpinin J (7), 1α-hydroxy-6-decaetoxysalpinin J (8), 6α-hydroxycaesall M (9), and 6α-hydroxy-14(17)-dehydrocaesalpin F (10), along with eight known compounds (11-18), were isolated from the pericarps of Caesalpinia bonduc. Compounds 1-3 and 11 are methyl-migrated cassane-type diterpenoids with a 19(4→3)-cassane skeleton. The structures of 1-10 were elucidated on the basis of 1D and 2D NMR methods and other spectroscopic analysis. The neuroprotective effects of the isolated compounds were evaluated.

Five new polyketides including three new butenolides (1-3), one new diphenyl ether (4), and one new benzophenone (5), together with eleven known compounds (6-16) were isolated from a wetland fungus Aspergillus flavipes PJ03-11. Their structures were elucidated on the basis of detailed spectroscopic analysis. All the isolated compounds were tested for their α-glucosidase inhibitory activities. The results showed that compounds 1-3, 6, 7, 11, 15 and 16 exhibited stronger inhibitory activities than acarbose. And the preliminary structure-activity relationships of aspulvinone and diphenyl ether compounds on the α-glucosidase inhibitory activity were reported., (Copyright © 2015 Elsevier Ltd. All rights reserved.)