Synthesis of sinomenine derivatives with potential anti-leukemia activity.

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 H2S-donating sinomenine derivatives were synthesized. Target hybrids a11 displayed substantial cytotoxic effects on cancer cell lines, particularly against K562 cells, with an IC50 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.

New aporphine alkaloids with antitumor activities from the roots of Thalictrum omeiense.

Two new aporphine alkaloids, 6aR-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 IC50 values ranging from 23.73 to 34.97 µM.

Antiproliferative polycyclic polyprenylated acylphloroglucinols from Garcinia paucinervis.

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 IC50 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.

[Lignans from stems and leaves of Cephalotaxus fortunei (â ¡)].

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-ß-D-glucopyranoside(6), and dihydrodehydrodiconiferyl alcohol 4-O-ß-D-glucopyranoside(7). Compounds 2 and 5 were isolated from the Cephalotaxus plant for the first time.

Apoptotic effects of phenols from the twigs and leaves of Garcinia nujiangensis.

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 CH2Cl2 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 IC50 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 G2 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 ß-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.

Two new iridoid glycosides from Odontites vulgaris.

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.

Cytotoxic alkaloids from the fruit pods of Macleaya microcarpa.

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 (IC50: 6.00 µM) and 2 (IC50: 6.82 µM) exhibited strong inhibitory activity against the HeLa cells and are worthy of further study.

Stilbenes with potent cytotoxicity from the seedcases of Paeonia suffruticosa Andrews.

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 IC50 values of 4.89-8.61 µM. The preliminary antitumor structure-activity relationship of these stilbenes is discussed as well.

(±)-Pheharmines A-B, two pairs of racemic alkaloids with a morpholino[4,3,2-hi]ß-carboline core, from the roots of Peganum harmala.

Two pairs of unprecedented ß-carboline-phenylpropanoid heterogeneous alkaloids, (±)-pheharmines A-B (1-4), characterized by a morpholino[4,3,2-hi]ß-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.

Cephalotaxine-type and homoerythrina-type alkaloids with antiproliferative effects from Cephalotaxus fortunei.

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 ß-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 GI50 values of 0.24-29.55 µM. Hainanensine (31) was the most active against two cancer cell lines with GI50 values of 0.24 ± 0.07, and 0.29 ± 0.01 µM, respectively.

[Isoquinoline alkaloids from two species of Thalictrum genus plants].

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.

Isolation, molecular characterization, immunological and anticoagulatant activities of polysaccharides from frankincense and its vinegar processed product.

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.

Anti-tumor alkaloids from Peganum harmala.

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 IC50 value of 3.05 µM. Norharmane displayed a moderate inhibition against A549 and HepG-2 cells with IC50 values of 16.45 µM and 17.27 µM, respectively.

New tirucallane-type triterpenoids from the resin of Boswellia carteriiand their NO inhibitory activities.

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 IC50 value of 7.58 ± 0.87 µmol·L-1.

Cephalotaxine-type alkaloids with antiproliferation effects from the branches and leaves of Cephalotaxus fortunei var. alpina.

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 GI50 values of 4.21-23.70 µM. 4 and 5 were the most active against U937 cells with GI50 values of 4.21 and 6.58 µM and against HL-60 cells with GI50 values of 6.66 and 6.70 µM, respectively. 4 and 5 arrested HL-60 cell cycle in G0/G1 phase.

Pegaharmols A-B, Axially Chiral ß-Carboline-quinazoline Dimers from the Roots of Peganum harmala.

Two nonbiaryl axially chiral ß-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 ß-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.

Baicalensines A and B, Two Isoquinoline Alkaloids from the Roots of Thalictrum baicalense.

Baicalensines A (1) and B (2) were isolated from the roots of Thalictrum baicalense and structurally characterized using spectroscopic data, 13C 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.

A new xanthyletin-type coumarin from the roots of Peucedanum praeruptorum.

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 IC50 values of 9.97, 27.80, and 48.68 µM, respectively. [Formula: see text].

Polyprenylated xanthones from the twigs and leaves of Garcinia nujiangensis and their cytotoxic evaluation.

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 IC50 values of 4.12 and 2.67 µM and 16 demonstrated the most potent activity against MCF-7 cell line with an IC50 value of 3.36 µM.

New lignanamides and alkaloids from Chelidonium majus and their anti-inflammation activity.

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 IC50 values of 25.3 ±â€¯0.5 and 23.5 ±â€¯1.7 µM, respectively.