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Toads produce potent toxins, named bufadienolides, to defend against their predators. Pharmacological research has revealed that bufadienolides are potential anticancer drugs. In this research, we reported nine bufadienolides from the eggs of the toad Bufo bufo gargarizans, including two new compounds (1 and 3). The chemical structures of 1 and 3, as well as of one previously reported semisynthesized compound (2), were elucidated on the basis of extensive spectroscopic data interpretation, chemical methods, and X-ray diffraction analysis. Compound 1 is an unusual 19-norbufadienolide with rearranged A/B rings. A biological test revealed that compounds 2 and 4-8 showed potent cytotoxic activities toward human melanoma cell line SK-MEL-1 with IC50 values less than 1.0 μM. A preliminary mechanism investigation revealed that the most potent compound, 8, could induce apoptosis via PARP cleavage, while 5 and 6 significantly suppressed angiogenesis in zebrafish. Furthermore, an in vivo biological study showed that 5, 6, and 8 inhibit SK-MEL-1 cell growth significantly.

Fischdiabietane A (1), a novel asymmetric diterpenoid dimer with a unique nonacyclic 6/6/6/5/7/6/6/6/6 ring system possessing unprecedented 2-oxaspiro[4.5]decane-1-one and 2-oxabicyclo[3.2.2]nonane frameworks in D/E/F rings, was isolated from the roots of Euphorbia fischeriana. Its structure was determined by spectroscopic techniques, electronic circular dichroism calculations, and X-ray diffraction experiments. Notably, 1 is the first abietane-type [4 + 2] Diels-Alder dimer identified from nature. The IC50 of 1 against T47D cells was about sixfold higher than that of cisplatin (the positive control). Furthermore, 1 induced apoptosis in T47D cells through the activation of caspase-3 and the degradation of poly(ADP-ribose) polymerase.

A phytochemical investigation of the roots of Euphorbia fischeriana Steud. led to the isolation of eleven undescribed gallotannins, fishertannins A-K, together with four known analogues. Their structures were elucidated by the comprehensive spectroscopic data including UV, IR, HR-ESI-MS, and NMR, while the absolute configurations of the sugar moiety were determined by the acid hydrolysis and HPLC analyses. Fishertannin A possessed an unusual skeleton comprised of acetophenone, galloyl group, arabinofuranosyl and glucopyranosyl moieties. Fishertannin B, fishertannin H, fishertannin K, 1,2,3-tri-O-galloyl-β-D-glucopyranose, 3,4,6-tri-O-galloyl-D-glucopyranose, and 1,6-di-O-galloyl-β-D-glucopyranose displayed the potent α-glucosidase inhibitory activities with the IC

Toad venom (Chansu) is used in the treatment of infectious and inflammatory diseases in China and East/Southeast Asian countries. However, the anti-inflammatory components of toad venom have not yet been systematically evaluated and clearly defined. To investigate the anti-inflammatory effects of toad venom and identify new anti-inflammatory ingredients, we used zebrafish, an alternative drug screening model, to evaluate the anti-inflammatory effects of 14 bufadienolides previously isolated from toad venom. Most of the bufadienolides were found to exert significant anti-inflammatory effects on lipopolysaccharide-, CuSO4-, or tail transection-induced zebrafish inflammatory models. Moreover, gammabufotalin ( 6) inhibits lipopolysaccharide-induced inflammation by suppressing the myeloid differentiation primary response 88/nuclear factor-kappa B and STAT3 signal pathways. This study confirms the potential of zebrafish in drug screening, clarifies the anti-inflammatory effects of bufadienolides from toad venom, and indicates that gammabufotalin may be developed as a novel therapeutic agent for inflammatory diseases in the future.

Neuraminidase inhibitors (NAIs) are the mainstay antiviral drugs against influenza infection. In this study, a ligand fishing protocol was developed to screen NAIs using neuraminidase immobilized magnetic beads (NA-MB). After verifying the feasibility of NA-MB with an artificial mixture including NA inhibitors and non-inhibitors, the developed ligand fishing protocol was applied to screen NAIs from the crude extracts of Duchesnea indica Andr. Twenty-four NA binding compounds were identified from the normal butanol (n-BuOH) extract of D. indica as potential NAIs by high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC–Q-TOF-MS) assisted with Compound Structure Identification (CSI):FingerID, including 12 ellagitannins, 4 brevifolin derivatives, 3 ellagic acid derivatives, and 4 flavonoids. Among them, 9 compounds were isolated and tested for in vitro NA inhibitory activities against NA from Clostridium perfringens, and from oseltamivir sensitive and resistant influenza A virus strains. The results indicate that compound B23 has the NA inhibitory activities in both the oseltamivir sensitive and resistant viral NA, with half maximal inhibitory concentration (IC50) values of 197.9 and 125.4 μmol/L, respectively. Moreover, B23 can obviously reduce the replication of oseltamivir sensitive and resistant viruses in Madin–Darby canine kidney (MDCK) cells at the concentrations of 40 and 200 μmol/L., Graphical abstract An efficient neuraminidase ligand fishing protocol was developed and verified to rapidly screen the neuraminidase inhibitors (NAIs) from natural sources. Twenty-four potential neuraminidase inhibitors were identified from Duchesnea indica as potential NAIs by HPLC–Q-TOF-MS. One compound can inhibit neuraminidase activities in both the oseltamivir sensitive and resistant virus strains.Image 1, Highlights • An efficient ligand fishing protocol was developed to rapidly screen the neuraminidase inhibitors from natural sources. • 24 potential neuraminidase inhibitors were identified from Duchesnea indica as potential NAIs by HPLC-Q-TOF-MS. • One compound can inhibit neuraminidase activities in both the oseltamivir sensitive and resistant virus strains.

Five new matrine-type alkaloid dimers, alopecuroides A-E, were isolated from the aerial parts of Sophora alopecuroides. Alopecuroides A and B represent the first dimeric matrine-type alkaloids possessing a cyano group and an epoxy moiety. Alopecuroides C and D are dimeric matrine-type alkaloids connected via C-2-C-9' and C-10-C-3' bonds, respectively. The chemical structures of alopecuroides A-E were elucidated by spectroscopic methods combined with single-crystal X-ray diffraction analysis. The anti-inflammatory effects of alopecuroides A-E were evaluated, and alopecuroide B exhibited the most significant activity, better than that of matrine, the representative compound from S. alopecuroides.

Three pairs of dimeric phenylpropanoyl–phloroglucinol enantiomers, (+)- and (−)-xanthchrysones A–C [(+)- and (−)-1–3], as well as their postulated biosynthetic precursors, were isolated and identified from the leaves of Xanthostemon chrysanthus. Compound 1 featured an unprecedented bis-phenylpropanoyl-benzo[b]cyclopent[e] oxepine tricyclic backbone. Compounds 2 and 3 represent the first examples of 1-(cyclopentylmethyl)-3-(3-phenylpropanoyl)benzene scaffold. The structures and absolute configurations of 1–3 were determined by spectroscopic and X-ray diffraction analysis as well as electronic circular dichroism (ECD) calculation. Both (+)-2 and (−)-2 showed moderate antibacterial activities including several multidrug-resistant strains.

Jatrogricaine A (1), a new diterpenoid possessing a 5/6/6/4 carbon ring system, together with eight known diterpenoids (2-9) were isolated from the stems of Jatropha podagrica. Their structures were elucidated by extensive spectroscopic methods and the absolute configuration of 1 was determined by single crystal X-ray diffraction analysis. All compounds were evaluated for their anti-inflammatory activities in vitro, and compound 3 showed significant inhibitory effects against nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells with an IC50 of 13.44 ± 0.28 μmol·L-1, being comparable to the positive control, quercetin (IC50 17.00 ± 2.10 μmol·L-1).

In order to study the alkaloids from branches and leaves of Ervatamia hainanensis, silica gel, ODS, Sephadex LH-20 and HPLC chromatography were used to obtain six alkaloids from the branches and leaves of E. hainanensis with use of. Based on the physicochemical properties and spectral data, their structures were identified as 10-hydroxydemethylhirsuteine(1), 3R-hydroxycoronaridine(2), 3-(2-oxopropyl)coronaridine(3), pandine(4), 16-epi-vobasine(5), and 16-epi-vobasinic acid(6). Among them, compound 1 was a new monoterpenoid indole alkaloid, and compounds 5 and 6 were obtained from this plant for the first time.

Toads produce potent toxins, named bufadienolides, to defend against their predators. Pharmacological research has revealed that bufadienolides are potential anticancer drugs. In this research, we reported nine bufadienolides from the eggs of the toad Bufo bufo gargarizans, including two new compounds (1 and 3). The chemical structures of 1 and 3, as well as of one previously reported semisynthesized compound (2), were elucidated on the basis of extensive spectroscopic data interpretation, chemical methods, and X-ray diffraction analysis. Compound 1 is an unusual 19-norbufadienolide with rearranged A/B rings. A biological test revealed that compounds 2 and 4–8 showed potent cytotoxic activities toward human melanoma cell line SK-MEL-1 with IC(50) values less than 1.0 μM. A preliminary mechanism investigation revealed that the most potent compound, 8, could induce apoptosis via PARP cleavage, while 5 and 6 significantly suppressed angiogenesis in zebrafish. Furthermore, an in vivo biological study showed that 5, 6, and 8 inhibit SK-MEL-1 cell growth significantly.

Fischdiabietane A (

Ethnopharmacological relevance Chansu, dried secretions from Bufonidae, has long been used for cancer treatment as a traditional Chinese medicine. In searching for effective anti-hepatoma agents from Chansu, our preliminary drug screening found that a bufadienolide, namely 1β-hydroxyl-arenobufagin (1β–OH–ABF), displays anti-hepatoma activities. However, the anti-hepatoma effects and molecular mechanisms of 1β–OH–ABF have not been defined. Aim of the study To evaluate the anti-hepatoma activity of 1β–OH–ABF against liver cancer Hep3B and HepG2 cells in vitro and in vivo, as well as explore the underlying mechanisms. Materials and methods The anti-proliferative effects of 1β–OH–ABF on liver cancer Hep3B, HepG2, HuH7, SK-HEP-1 and normal hepatocyte LO2 cells were examined by MTT assay and colony formation assay. Hoechst 33258 staining and Annexin V-FITC/PI staining assay were used to analyze apoptosis induced by 1β–OH–ABF. The collapse of the mitochondrial membrane potential (ΔΨm) was detected by JC-1 staining assay. Western blotting was used to examine the expression levels of targeted proteins. The role of mTOR in 1β–OH–ABF-induced apoptosis was investigated using small interfering RNA (siRNA) transfection. Zebrafish xenograft model was established to evaluate the anti-hepatoma effects of 1β–OH–ABF in vivo. Results We found that 1β–OH–ABF inhibits the proliferation of Hep3B, HepG2, HuH7, SK-HEP-1 cells but has little cytotoxicity towards LO2 cells. 1β–OH–ABF induces mitochondria dysfunction and triggers mitochondria apoptotic pathway, which is accompanied by the loss of ΔΨm, upregulation and translocation of Bax, as well as cleavages of caspase-9, caspase-3 and PARP. Mechanistically, 1β–OH–ABF markedly decreases the expression level of p-AKT/AKT and p-mTOR (Ser2248 and Ser2481)/mTOR in a time-dependent manner. Inhibition of mTOR by siRNA strengthens 1β–OH–ABF-mediated apoptosis. Critically, 1β–OH–ABF shows a marked in vivo anti-hepatoma effect on human Hep3B cell xenografts in zebrafish model. Conclusion 1β–OH–ABF induces mitochondrial apoptosis through the suppression of mTOR signaling in vitro and in vivo, indicating that 1β–OH–ABF may serve as a potential agent for the treatment of liver cancer.

Bufadienolides are cardioactive C24 steroids with an α-pyrone ring at position C17. In the last ten years, accumulating studies have revealed the anticancer activities of bufadienolides and their underlying mechanisms, such as induction of autophagy and apoptosis, cell cycle disruption, inhibition of angiogenesis, epithelial-mesenchymal transition (EMT) and stemness, and multidrug resistance reversal. As Na+/K+-ATPase inhibitors, bufadienolides have inevitable cardiotoxicity. Short half-lives, poor stability, low plasma concentration and oral bioavailability in vivo are obstacles for their applications as drugs. To improve the drug potency of bufadienolides and reduce their side effects, prodrug strategies and drug delivery systems such as liposomes and nanoparticles have been applied. Therefore, systematic and recapitulated information about the antitumor activity of bufadienolides, with special emphasis on the molecular or cellular mechanisms, prodrug strategies and drug delivery systems, is of high interest. Here, we systematically review the anticancer effects of bufadienolides and the molecular or cellular mechanisms of action. Research advancements regarding bufadienolide prodrugs and their tumor-targeting delivery strategies are critically summarized. This work highlights recent scientific advances regarding bufadienolides as effective anticancer agents from 2011 to 2019, which will help researchers to understand the molecular pathways involving bufadienolides, resulting in a selective and safe new lead compound or therapeutic strategy with improved therapeutic applications of bufadienolides for cancer therapy.

Six new cassaine diterpenoids (1, 3–7), along with three known ones (2, 8–9) were isolated from the seeds of Erythrophleum fordii. Their structures were elucidated by extensive spectroscopic methods and acid hydrolysis. Compound 2 was tested to be the most potent one and showed more sensitive activities on MCF-7 and A549 cancer cells with IC50 values of 3.66 ± 1.20 and 2.87 ± 0.46 μM, respectively. Furthermore, compound 2 reduced the number of cell colonies significantly in a dose-dependent manner in the colony formation assay and triggered apoptosis of MCF-7 cell.

Objective To compare the clinical efficacy difference between comprehensive ying needling therapy and intramuscular injection with ribavirin for mumps. Methods One hundred patients with mumps were randomly divided into comprehensive ying needling therapy group (group A, 52 cases) and western medicine group (group B, 48 cases), then 8 cases were eliminated and drop out from group A and 4 cases were eliminated and drop out from group B respectively, actual inclusion 44 cases in group A 44 cases in group B. Point bloodletting was performed at parotid gland (腮腺Sāixian) and Threeshang acupoints of the patients in group A for once every other day, treatment for 7 days was considered as 1 course of treatment, and 2 courses were needed. Intramuscular injection with ribavirin was given to the patients in group B for twice a day, treatment for 7 days was considered as 1 course, and 2 courses were needed. The parotid gland swelling score, fever score, orifice parotid duct swelling score, score of difficulty in opening mouth and the clinical efficacy of the patients in the two groups were compared before and after treatment. Results The cured and markedly effective rate in group A was 90.9% (40/44), which was superior to 68.2% in group B (30/44) (P Conclusion The curative effect of comprehensive ying needling therapy for treatment of mumps was superior to that of conventional western medicine therapy.

Callisretones A (1) and B (2), two rearranged phloroglucinol-monoterpenoid adducts featuring an unprecedented isopropylcyclopenta[b]benzofuran backbone, together with their postulated biosynthetic precursors (3–9), were isolated from Callistemon rigidus. The previously assigned absolute configurations of viminalins H (7), L (8), and N (9) were revised and unequivocally established by X-ray diffraction data. A putative biosynthetic pathway toward callisretones A and B involving the rearrangement of the terpenoid motif is proposed. In addition, 1 and 2 showed inhibitory effects on nitric oxide production with IC50 values of 15.3 ± 1.0 and 17.7 ± 1.1 μM, respectively.

Objective To compare the clinical efficacy between electroacupuncture combined with heat-sensitive moxibustion and western medicine for treatment of premature ovarian failure. Methods Eighty patients were randomly divided into an electroacupuncture combined with heat-sensitive moxibustion group (group A, n=40) and a western medicine group (group B, n=40). Zigōng ( EX-CA 1), Xuehâi ( SP 10), Gānshū ( BL 18) and Shenshū ( BL 23) were selected in group A, and acupuncture combined with heat-sensitive moxibustion were carried out. Climen was taken orally in group B. The score changes of menstrual cycle, tidal fever and sweatiness, emotional excitement, soreness and weakness of waist and knees, dizziness and tinnitus, as well as the cured and markedly effective rate of the patients in the two groups before and after two courses of treatment were compared. Results The cured and markedly effective rate of group A was 72.5% (29/40), which was superior to that of group B (37.5%, 15/40) (P Conclusion The efficacy of electroacupuncture combined with heat-sensitive moxibustion is superior to that of conventional western medicine in treatment of premature ovarian failure.

In the present study, two new diterpenoid lactones, 3-deoxy-andrographoside (1) and 14-deoxy-15-methoxy-andrographolide (2), were isolated from the aerial parts of Andrographis paniculata. Their structures were elucidated by combination of NMR, MS, and chemical methods. The configurations of 1 and 2 were established based on the analysis of ROESY data and single crystal X-ray diffraction experiment.

Bufospirostenin A (1) and bufogargarizin C (2), two novel steroids with rearranged A/B rings, were isolated from the toad Bufo bufo gargarizans. Compound 1 represents the first spirostanol found in animals. Compound 2 is an unusual bufadienolide with a cycloheptatriene B ring. Their structures were elucidated by spectroscopic analysis, single crystal X-ray diffraction analysis, and computational calculations.

Three pairs of bufadienolide l/d-lactate epimers (1-6) were isolated from the eggs of the toad Bufo bufo gargarizans. The structures were elucidated by using spectroscopic methods, X-ray diffraction analysis and a modified Mosher's method. Compounds 1-6 represent the first occurrence of lactate-conjugated bufadienolides in nature, and illustrate the existence of an enzyme-controlled epimerization from l- to d-lactate in amphibians. The biosynthetic pathways, in which two key enzymes might be involved (i.e., lactate racemase and acyltransferase), were proposed. In addition, the biological assays revealed that compounds 1-4 are potent cytotoxic agents against human gastric cancer cells BGC-823 and human lung cancer cells A549 with IC50 values in a range of 8.0 to 80.0 nM.

Five new matrine-type alkaloid dimers, alopecuroides A-E, were isolated from the aerial parts of

Erythrosides A-G, seven undescribed oleanane-type triterpenoid saponins, were isolated from the seeds of Erythrophleum fordii. Their structures with absolute configurations were determined by extensive spectroscopic analysis including one-dimensional [1D] and two-dimensional [2D] nuclear magnetic resonance [NMR], high-resolution electrospray ionization mass spectroscopy [HR-ESI-MS] analysis, and chemical methods. Erythrosides A-G featured a diverse oligosaccharide chain containing 4–6 pentoses or hexoses at C-3 and a monoterpenic acid or a (E)-cinnamic acid unit at the C-21 position. Of particular interest, erythrosides A-C, E and F contained a rare alpha xylose in their sugar chains. The bioassay results indicated that erythrosides A-C showed moderate cytotoxic activities against human lung cancer cell line PC9 with IC50 values of 13.14, 16.67 and 17.59 μM, respectively (the positive control, Taxol, IC50 = 0.60 nM).

Three pairs of dimeric phenylpropanoyl-phloroglucinol enantiomers, (+)- and (-)-xanthchrysones A-C [(+)- and (-)

Chemical investigation of the aerial parts of

Toad venom (venenum bufonis, also called Chan'su) has been widely used for centuries in China to treat different diseases, especially for cancer. Bufadienolides are mainly responsible for the anti-cancer effects of toad venom. However, systematic chemical composition and cytotoxicity as well as key pharmacophores of these bufadienolides from toad venom have not yet been defined clearly. To enrich the understanding of the diversity of bufadienolides and to find bufadienolides with better activities from toad venom. This study was carried out to isolate chemical constituents, research their anti-tumor effects and mechanisms by MTT assay, flow cytometry and Western blotting, and develop a CoMFA and CoMSIA quantitative structure-activity relationship (QSAR) model for illustrating the vital relationship between the chemical structures and cytotoxicities. Among 47 natural bufadienolides, most of bufadienolides (21 compounds isolated in this study and 26 compounds isolated previously) could significantly inhibit the proliferation of cancer cells, and compounds 1, 8, 12, 18 and 19 showed the most potent inhibitory activity against four types of human tumor cells. Compound 18 induced G2/M cell cycle arrest and apoptosis. Moreover, 3D contour maps generated from CoMFA and CoMSIA identified several pharmacophores of bufadienolides responsible for the anti-tumor activities. Our study might provide reliable information for future structure modification and rational drug design of bufadienolides with anticancer activities in medical chemistry.

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).

Two novel monoterpenoid indole alkaloids (MIAs), gelsechizines A-B (1-2), along with four known ones (3-6) were isolated from the fruits of Gelsemium elegans. Compound 1 features a new carbon skeleton with two additional carbon atoms forming a 4-methylpyridine unit. Their structures with absolute configurations were elucidated by NMR, MS, X-ray diffraction and electronic circular dichroism (ECD) calculations. Compounds 1-3 showed significant anti-inflammatory effects in vivo and in vitro, which may be related to the inhibition of the trecruitment of neutrophils and macrophages as well as the secretion of TNF-α and IL-6. Preliminary structure-activity relationship analysis revealed that the β-N-acrylate moiety plays an important role in the anti-inflammatory effect.

Six new hirundigenin-type C21 steroidal glycosides, namely hirundigosides E–J (1–6), were obtained from the dried roots of Cynanchum stauntonii. Their chemical structures were elucidated by analyses of HR ESI-TOF MS, 1D, 2D-NMR, and X-ray crystallographic methods together with acidic hydrolysis. Interestingly, they exist in nature as epimers owing to the presence of 14-hemiketal hydroxyl group. Moreover, it is striking that only one set of resonance signals (14β-OH epimer) appeared in the 1H and 13C NMR spectra of compounds 1–6 when measured in CDCl3, while two sets of resonance signals (14α- and 14β-OH epimers) were observed when measured in pyridine-d5. It may ascribe to the favorable formation of intramolecular hydrogen bond of aglycone due to the proximate distance of hydroxyl group and oxygen atoms (1.86 nm) in 14β-OH epimer in CHCl3. The difference of potential energy (ΔG) of 14α-OH epimer to 14β-OH epimer is about 0.73 kcal mol−1 for compound 1 in CHCl3, while it is unfavorable for the formation of intramolecular hydrogen bond in pyridine and the G values of them are almost equal in 1. Also, CDCl3 is neither protic solvent nor Lewis acid and it can't induce the isomerization of hemiketal hydroxyl group in hirundigosides, while pyridine is Lewis base and it promotes the isomerization of hirundigosides. In addition, secondary anhydrohirundigenin-type glycosides and anhydrohirundigenin were obtained by mild acidic hydrolysis and their anti-inflammatory activities were also discussed.

Two new 19-norbufadienolides (1 and 2), one new 14,15-epoxy bufadienolide (3), and eight rare bufadienolide–fatty acid conjugates (4–11), together with four known ones (12–15) were isolated from the eggs of toad Bufo bufo gargarizans. Their chemical structures were elucidated by extensive spectroscopic methods in combination with X-ray diffraction analyses. Furthermore, we tested the inhibitory effect of these compounds against breast cancer cell lines MCF-7 and MDA-MB-231. Most of them showed strong cytotoxicity with IC50 values less than 0.1 μM. The further mechanistic study showed that they could induce apoptosis and cycle arrest in the G2/M phase in MCF-7 cells.

To enhance the structural diversity of tanshinones and provide more derivatives for the biological studies, a one-pot combinatorial modification strategy was performed on total tanshinones. Six new quinoxlinetanshinones 1–6 were subsequently isolated from the combinatorial modified semi-synthetic mixture. The structures were elucidated by spectroscopic analysis in combination with single-crystal X-ray diffraction. These quinoxlinetanshinones demonstrated strong DNA binding properties. Rapid synthesis of new quinoxlinetanshinones with significant biological activity highlights the great potential of one-pot combinatorial modification for the diversification of natural products.

A novel polyvinylidene fluoride (PVDF) membrane, i.e. Ag/TiO 2 /PVDF composite membrane, was prepared via the blending/photo reduction combined method in this paper. And the influence of Ag/TiO 2 embedment on the surface property of PVDF membrane was discussed, including the surface hydrophilicity and visible-light response activity. ATR/FTIR characterization certified that amount of hydroxyl group ( OH) was formed on the PVDF membrane surface owing to the embedment of Ag/TiO 2. The results suggested that the increased hydrophilicity of PVDF membrane can be achieved through the addition of Ag/TiO 2 nanoparticles because the surface hydroxyl group ( OH) had great contribution to membrane hydrophilicity. The increased hydrophilicity was also demonstrated by the contact angle measurement. In a word, Ag/TiO 2 improved the surface hydrophilicity of PVDF membrane in contrast with virgin PVDF membrane. Besides, Ag/TiO 2 nanoparticle provided PVDF membrane with an enhanced visible-light response activity. Ag/TiO 2 /PVDF composite membrane showed excellent activity on degradation of methylene blue (MB) and inactivation of bacterial under visible-light illumination. I hope this research can provide a new way for PVDF surface modification.

Eleven new cassane-type diterpenoids (1–11), along with 12 known compounds were isolated from the seeds of Caesalpinia minax Hance. Their structures were determined by extensive spectroscopic methods in combination with X-ray diffraction analysis. All the compounds were evaluated for COX-2 inhibitory activity, and displayed different levels of inhibition except for 14 whose C and D rings were connected through a spiro-atom. Among them, compound 23, a furanoditerpenoid lactone with a hydroxyl group at C-1 displayed the most potent inhibitory activity with an inhibition ratio of 82.0% at 4.0 μM, which was stronger than its analog 16 with an additional hydroxyl group at C-2. Further detailed testing showed that both compounds 23 and 16 dose-dependently inhibited the COX-2 enzyme with IC50 values of 2.4 ± 0.1 and 3.2 ± 0.2 μM, respectively. Molecular docking analysis showed significant hydrogen bonding and π–π interactions with the enzyme, and revealed the docking scores 36.3108 and 28.6678 for 23 and 16, respectively, which are consistent with their IC50 values. Cytotoxic assay showed that all these diterpenoids only exhibit weak activities with IC50 values over 50 μM on normal cells. Thus, these diterpenoids might be potential anti-inflammatory agents targeting the COX-2 enzyme with low toxicity.

The current study explored the Na+/K+-ATPase (NKA) inhibition-independent proarrhythmic mechanisms of cardiac glycosides (CGs) which are well-known NKA inhibitors. With the cytosolic Ca2+ chelated by EGTA and BAPTA or extracellular Ca2+ replaced by Ba2+, effects of bufadienolides (bufalin (BF) and cinobufagin (CBG)) and cardenolides (ouabain (Oua) and pecilocerin A (PEA)) on the L-type calcium current (I Ca,L) were recorded in heterologous expression Cav1.2-CHO cells and human embryonic stem cell-derived cardiomyocytes (hESC-CMs). BF and CBG demonstrated a concentration-dependent (0.1 to 100 µM) I Ca,L inhibition (maximal ≥50%) without and with the NKA activity blocked by 10 µM Oua. BF significantly shortened the action potential duration at 1.0 µM and shortened the extracellular field potential duration at 0.01~1.0 µM. On the other hand, BF and CBG at 100 µM demonstrated a strong inhibition (≥40%) of the rapidly activating component of the delayed rectifier K+ current (I Kr) in heterologous expression HEK293 cells and prolonged the APD of the heart of day-3 Zebrafish larva with disrupted rhythmic contractions. Moreover, hESC-CMs treated with BF (10 nM) for 24 hours showed moderate yet significant prolongation in APD90. In conclusion, our data indicate that CGs particularly bufadienolides possess cytosolic [Ca2+]i- and NKA inhibition- independent proarrhythmic potential through I Ca,L and I Kr inhibitions.

Three new 6,6-spiroketal polyketides, streptospirodienoic acids A (1), B (2) and streptospirodienoate A (3), were obtained from the fermentation broth of Streptomycetes sp. (no. 0950134). Their structures were constructed by one 6,6-spiroketal core coupled with hexadienoic acid, in which the starter unit might be 2-methylpropionyl-CoA. Their chemical structures were determined by detailed analyses of UV, IR, HRESIMS, 1D, 2D-NMR spectroscopic data and the X-ray crystallography technique. The biosynthetic pathway for 1 and 2 was proposed. Compound 3 showed moderate cytotoxic activity against HCT-116 cells (IC50 = 5.2 μM), while compounds 1 and 2 showed no activity (IC50 > 10.0 μM).

One new stenine-type alkaloid, tuberostemonine D ( 1 ), together with five known stenine-type alkaloids ( 2 – 6 ) and two known stemoninine-type alkaloids ( 7 and 8 ), were isolated from the roots of Stemona tuberosa . Their structures were elucidated by extensive spectroscopic methods (IR, UV, MS, 1D and 2D NMR), and the structure of 1 was further confirmed by X-ray diffraction analysis. First simultaneous isolation of stenine- and stemoninine-type alkaloids not only added a new chemical type and increased the chemical diversity of Stemona tuberosa , but also provided chemotaxonomic clues for the close relationship between genera Stemona and Stichoneuron , and favored retaining them in the same family.

Five new sesquiterpenoids Nardosinanone A–E (1–5), were isolated from the extract of Nardostachys chinensis, and their structures were determined by extensive spectroscopic analysis. Compound 1 featured a nardosinane sesquiterpenoid with an unusual tricyclic skeleton. Compounds 2–4 were new nardosinane sesquiterpenoids bearing a rare 10,11-epoxy group. The absolute configurations were determined by single-crystal X-ray diffraction analysis, ECD calculation method, the CD analysis of the in situ formed [Rh2(OCOCF3)4] complex, and the CD data analysis based on the octane rule of cyclohexanone.