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Nine new highly oxygenated 3,5-dimethylorsellinic acid-derived meroterpenoids, talaromynoids A-I (1-9), were isolated from the marine-derived fungus Talaromyces purpureogenus SCSIO 41517. Their structures including absolute configurations were elucidated by HRMS, NMR, single-crystal X-ray diffraction analysis, and electronic circular dichroism calculations. Compounds 1 and 7-9 possessed unprecedented 5/7/6/5/6/6, 6/7/6/6/6/5, 6/7/6/5/6/5/4, and 7/6/5/6/5/4 polycyclic systems, respectively. Biologically, compound 5 showed selective inhibitory activity against phosphatase CDC25B with an IC50 value of 13 μM. Moreover, 7-9 and 12 exhibited the activity of reducing triglyceride in 3T3-L1 adipocytes in a dosage-dependent manner.

(+)- and (-)-talaromyoxaones A and B (1 and 2, respectively), two new oxaphenalenone derivatives with a hemiacetal frame and an unprecedented spirolactone frame of a 2'H,3H,4'H-spiro[isobenzofuran-1,3'-pyran]-3-one unit that show biosynthetic enantiodivergence, and two new oxaphenalenone analogues (±)-11-apopyrenulin (3) and (+)- or (-)-abeopyrenulin (4) were isolated from the marine-derived fungus Talaromyces purpureogenus SCSIO 41517. Their structures were elucidated by spectroscopic analysis, single-crystal X-ray diffraction, and quantum chemical calculations of ECD spectra. Compounds 1 and 2 showed selective inhibitory activity against phosphatases SHP1, SHP2, and MEG2 with IC50 values of 1.3-3.4 μM, and the potential modes of action for 1 were investigated by a preliminary molecular docking study.

Background:Sample preparation is one of the most challenging phases in pharmaceutical analysis, especially in biological matrices, affecting the whole analytical methodology.Objective:In this study, a new Ca(II)/Cu(II)/alginate/CuO Nanoparticles Hydrogel Fiber (CCACHF) was synthesized through a simple, green procedure and applied for fiber micro solid-phase extraction (FMSPE) of diazepam (DIZ) and oxazepam (OXZ) as model drugs prior to high-performance liquid chromatography-UV detection (HPLC-UV).Methods:Composition and morphology of the prepared fiber were characterized and the effect of main parameters on the fiber fabrication and extraction efficiency have been studied and optimized.Results:In optimal conditions, calibration curves were linear, ranging between 0.1–500 μg L−1with regression coefficients of 0.9938 and 0.9968. Limit of Detection (LOD) (S/N=3) and Limit of Quantification (LOQ) (S/N=10) of the technique for DIZ and OXZ were 0.03 to 0.1 μg L−1. Within-day and between-day Relative Standard Deviations (RSDs) for DIZ and OXZ were 6.0–12.5% and 3.3–9.4%, respectively.Conclusion:The fabricated adsorbent has been substantially employed to the extraction of selected benzo-diazepines (BZDs) from human serum real specimens and the obtained recoveries were also satisfactory (82.1-109.7%).

Manganese oxides (MnOx) have been extensively investigated due to their extremely high theoretical capacities for application as conversion anodes in lithium-ion batteries. However, fully performing their theoretical performance still faces poor electric conductivity and serious volume change upon lithium insertion/extraction. Herein, we demonstrate encapsulating manganese oxide nanoparticles within a conducting polymer polypyrrole (PPy) shell as a facile strategy to overcome such flaws through in situ redox reaction and oxidative polymerization process. Such an in situ method combines the redox reaction between potassium permanganate and tetrahydrofuran to form MnOx nanoparticles and the subsequent oxidative polymerization of pyrrole to form a conductive polypyrrole coating shell by the oxidant KMnO4 into one step. For the as-fabricated products (MnOx@PPy), this tenderly introduced conductive PPy shell highly favors the fast electron transfer and preserves the electrode structure integrity upon repeated cycling. As the anode for LIBs, MnOx@PPy exhibits superior lithium storage performance with a high reversible capacity (1538 mAh·g−1), long-life cyclability (747 mAh·g−1 after 1000 cycles at 1.0C) and durable ratability (574 mAh·g−1 at 2.0C). This work demonstrates that the convenient in situ strategy to form conductive polymer coating shell is effective to improve the performance of conversion anodes and can be extended to other materials for energy storage applications.

The coordination complex bis(1H-benzimidazole-κN3)cadmium(II) dibenzoate has been synthesized and characterized by single crystal diffraction analysis. Cadmium center is six coordinated and formed a distorted octahedron coordinated geometry. The Hirshfeld analysis shows that in the dnorm-surface of the compound, there are dark red spots near the hydrogen-bonds acceptor and donor atoms, while intermolecular interactions result in faint-red spots. The AIM analysis was performed, there exist a BCP in each N(C)–H∙∙∙O hydrogen bond, the bond paths also can be seen, the |V(b)|/G(b) < 1 and the H(b) > 0, the interaction is indicative of being a closed shell. The TG results are consistent with the X-ray diffraction structure.

Herein, a novel pillar[5]arene-based gemini-[1]rotaxane molecule DEP5 was successfully designed and synthesized. Interestingly, the gemini-[1]rotaxane DEP5 serving as a chemosensor could selectively recognize L-Arg with high sensitivity and its lowest detection limit (LOD) was 1.43 × 10−7 M. Simultaneously, the gemini-[1]rotaxane DEP5 could assemble into the microsphere structure and its microsphere morphology could transform into cross-linked supramolecular networks through host–guest interactions with L-Arg. Furthermore, its microsphere morphology could be recovered again by the addition of competitive reagent guest trifluoroacetic acid (TFA). Therefore, this work provides a new and simple approach to construct gemini-[1]rotaxane-based smart materials which could assemble into the microsphere in solution and achieve reversible regulation of morphology between the microsphere and cross-linked supramolecular networks by external chemical stimuli (L-Arg/TFA). This kind of material not only has a perspective in L-Arg sensors but also has potential for application in other fields such as drug control release.

In the present study, 2,6-bis(diphenylphosphino)pyridine ((Ph2P)2py)-supported cis- and trans-Pt2Ag2 alkynyl complexes were prepared and characterized by X-ray crystallography. Although the cis-Pt2Ag2 complexes are slightly emissive at ambient conditions, the trans-Pt2Ag2 complexes exhibit moderate photoluminescence in dichloromethane and have strong emission in the solid state, originating from aromatic acetylide to (Ph2P)2py ligand-to-ligand charge transfer (3LLCT) and Pt2Ag2 cluster metal-centered (3MC) triplet states. Remarkably, the trans-Pt2Ag2 complex [Pt2Ag2{(Ph2P)2py}2(CCC6H5)4](SO3CF3)2 exhibit remarkable luminescent vapochromism with emission red-shifts of 100 nm in response to MeCN vapor, arising from intramolecular structural conversion from staggered to parallel arrangements of two face-to-face Pt(CCC6H5)2 moieties, which results in the alteration of the excited-state energy in the solid state as supported by TD-DFT studies.

A novel photochemical sensor (FQ-5) based on quinoline-functionalized phenazine derivatives was designed and synthesized. The FQ-5 showed a good response to certain pH values in a wide pH range (from 2.0 to 13.0). Particularly, at pH = 12 and 13, the fluorescence emission showed obvious enhancement, the fluorescence quantum yields could reach 80.9% and 77.0%, respectively, and the color of solution changed from yellow to purple. Meanwhile, the sensor not only showed a rapid response toward CO2, but also showed high selectivity and sensitivity for the detection of L-Arg in buffer solution (pH = 7), and the limit of detection (LOD) was 8.1 × 10−8. Furthermore, the FQ-5-based fluorescent writing material and CO2 gas reaction device were developed for the rapid detection of L-Arg and CO2. Therefore, this work will provide a new approach for photochemical sensing in the detection of multiple substrates.

The copper-catalyzed cycloamination of indolylquinones and various (hetero)aromatic amines under ligand-free conditions for the synthesis of polycyclic N-heterocycles has been developed. This method allows facile access to polycyclic N-heterocycles with the tolerance of chloride, bromide, amino, thio, etc. groups in moderate to high yields (60-89%).

Developing novel stimuli-responsive fluorescent nanomaterials and achieving controllable regulation of the morphology and optical properties of this kind of material is very important. Herein, we demonstrate a novel way to construct stimuli-responsive fluorescent nanomaterials by rotaxanes. Significantly, a feasible method to reversibly control the morphology of nanomaterials from nanoparticles to nano-film has been developed. At the beginning of the work, a novel pillar[5]arene-based tri-[2]rotaxane was designed and synthesized. The tri-[2]rotaxane shows selective fluorescence response to suberic acid. Moreover, the tri-[2]rotaxane could self-assemble into fluorescent nanoparticles. By alternating addition of suberic acid and trimethylamine, the tri-[2]rotaxane-based nanomaterials could reversibly change from nanoparticles to nano-film, meanwhile, the fluorescence of the tri-[2]rotaxane shows “off–on–off” switch; this process is controlled by the formation and destruction of intermolecular hydrogen bonds. Reversible control of the morphology and optical properties of rotaxane-based nanomaterials have broad prospects in biomedicine and smart materials.

Multifunctional stimuli-responsive supramolecular polymers have applications in the field of smart materials. Herein, a tri-pillar[5]arene-based multifunctional stimuli-responsive supramolecular po...

The booming of host-guest assembly-based supramolecular chemistry provides abundant ways to construct functional systems and materials. Attracted by the important application prospect of white light emission and aggregation-induced emission (AIE) materials, herein, we report an efficient way for fabricating metal-free white light-emitting AIE materials through the supramolecular assembly of simple organic compounds: methoxyl pillar[5]arene (

The char samples were prepared from the coal impregnated with NaCl under different steam concentrations and temperatures. The mode of occurrence of sodium and the contents of sodium in different chars with the same conversion ratio were analyzed by inductively coupled plasma mass spectrometry. The effects of steam and temperature on the migration and transformation of sodium in the coal during the thermal conversion processes were studied. The results showed that the increase of steam concentration enhanced the release of water-soluble sodium during the thermal conversion of coal and promoted the transformation of water-soluble sodium into ammonium acetate, hydrochloric acid and insoluble sodium. As a result, the release of sodium was suppressed to a certain extent. It was also observed that increasing the reaction temperature could promote the release of water-soluble sodium and promote the transformation of water-soluble sodium to the other soluble forms of sodium. The evolution of char structure was an important influence on the release of sodium. The results revealed that the degrees of char condensation increased with the steam gasification reaction. The formation of large aromatic ring structures from the condensation of the small aromatic rings played the important role in the encapsulation of sodium, which would inhibit the release of sodium.

With the comprehensive promotion of ultralow emissions and world-class energy consumption standards, the disposal of the spent SCR (selective catalytic reduction of NOx with NH3) catalyst and fly a...

Mycosphazine A ( 1 ), a new iron(III) chelator of coprogen-type siderophore, and mycosphamide A ( 2 ), a new cyclic amide benzoate, together with six known aryl amides ( 3−8 ), were isolated from the fermentation broth of the deep-sea-derived fungus Mycosphaerella sp. SCSIO z059. Alkaline hydrolysis of 1 afforded a new epimer of dimerum acid, mycosphazine B ( 1a ), and a new bi-fusarinine-type siderophore, mycosphazine C ( 1b ). The planar structures of the new compounds were elucidated by extensive spectroscopic data analysis. The absolute configurations of amino acid residues in 1a and 1b were determined by acid hydrolysis. And the absolute configuration of 2 was established by quantum chemical calculations of the electronic circular dichroism (ECD) spectra. Compound 1 is the first siderophore-Fe(III) chelator incorporating both L-ornithine and D-ornithine unites. Compounds 3−8 were reported as natural products for the first time, and the 1H and 13C NMR data of 6 and 8 were assigned for the first time. Compounds 1 and 1a could greatly promote the biofilm formation of bacterium Bacillus amyloliquefaciens with the rate of about 249% and 524% at concentration of 100 μg·mL−1, respectively.

Stimuli-responsive optical materials attract lots of attention due to their broad applications. Herein, a novel smart stimuli-responsive supramolecular polymer was successfully constructed using a simple tripodal quaternary ammonium-based gelator (TH). The TH self-assembles into a supramolecular polymer hydrogel (TH-G) and shows aggregation-induced emission (AIE) properties. Interestingly, the transparency and fluorescence of the TH-G xerogel film (TH-GF) could be reversibly regulated by use of triethylamine (TEA) and hydrochloric acid (HCl) vapor. When alternately fumed with TEA and HCl vapor, the optical transmittance of the TH-GF was changed from 8.9% to 92.7%. Meanwhile, the fluorescence of the TH-G shows an "ON/OFF" switch. The reversible switching of the transparency and the fluorescence of the TH-GF is attributed to the assembly and disassembly of the supramolecular polymer TH-G. Based on these stimuli-response properties, the TH-GF could act as an optical material and shows potential applications as smart windows or fluorescent display material controlled by TEA and HCl vapor.

The objective of this study was to develop cancer drugs effective to take out both cancer stem cells (CSCs) and cancer cells, particularly CSCs since these cells stood in the way to deny the success of conventional therapies to put cancer away. The association of methylation enzymes with telomerase constitutes a unique abnormality of cancer cells. This abnormality locks methylation enzymes in an exceptionally stable and active state so that hypomethylation of nucleic acids necessary for the cells to undergo Terminal Differentiation (TD) cannot take place. Human body produces metabolites that are able to eliminate telomerase from abnormal methylation enzymes of cancer cells to allow TD to proceed. Cell Differentiation Agent-2 (CDA-2) is a preparation of human metabolites from freshly collected urine, which has been approved for cancer therapy by the Chinese FDA. The effective components of CDA-2 are Differentiation Inducers (DIs) to target on the telomerase of abnormal methylation enzymes and Differentiation Helper Inducers (DHIs) which are the inhibitors of individual enzymes of ternary methylation enzymes. CDA-2 was very effective for the therapy of Myelodysplastic Syndrome (MDS), which is a disease attributable to Cancer Stem Cells (CSCs). We have previously carried out extensive studies on the DHIs of CDA-2.We are now focusing on the DIs of CDA-2 in order to formulate synthetic CDA for the prevention and therapy of cancer via targeting of CSCs. DIs were purified from CDA-2 solution by procedures including differential solvent extraction, gel filtration, ion exchange chromatography, TLC, and HPLC. The mass of purified active preparation was determined by mass spectroscopy. DI activity was based on the Nitro Blue Tetrazolium (NBT) assay of HL-60 cells. DIs of CDA-2 were found predominantly as acidic liposomal complexes extractable by dichloromethane. A good proportion of which became covalently linked to inactive carriers which were not soluble in dichloromethane, but soluble in alcohols. We have identified pregnenolone as a DHI of active liposomal complexes. After dissociation from pregnenolone, the active DIs of CDA-2 were not associated with UV absorption peaks of HPLC. We suspected that the active DIs might be acidic peptides derived from endogenous proteins, because we have previously found that acidic peptides of CDA-2 were active DIs. We, thus, randomly picked pentapeptides containing at least two acidic amino acid residues from the sequences of \(\alpha\)- and \(\beta\)-hemoglobin for synthesis to test their DI activities. Indeed, acidic pentapeptides of hemoglobin were active as DIs, although the activities were not impressive. Retinoic Acid (RA) and 12-O-TetradecanoylPhorbol-13-Acetate (TPA) are well known DIs with much better activities. In this study, we found Pyrvinium Pamoate (PP) as the best DHI, and triinosinate + tetrainosinate (I3 + I4) as an acceptable DHI. With effective DIs and DHIs on hand, our deliberated CDA formulations were as followings: for the therapy of MDS, the CDA-MDS formulation was RA(ED25)-5P-1(ED25)-I3 + I4(RI0.5)-PP(RI0.5)-sodium pregnenolone sulfate(RI0.5); for the therapy of CSCs, the CDA-CSC formulation was RA(ED25)- TPA(ED25)-PP(RI0.5)-resveratrol(RI0.5)-curcumin(RI0.5); for the therapy of brain tumor, the CDA-BT formulation was TPA(2xED25)-PP(2xRI0.5)-sodium phenylbutyrate(RI0.5)-pyrogallol(RI0.5); and for the therapy of melanoma and pancreatic cancer, the CDA-M&P formulation was RA(ED25)-TPA(2xED25)- 5P-1(ED25)-PP(2xRI0.5)-sodium tannate (RI0.5). The above CDA formulations all produced 100% NBT + on HL-60 cells. In conclusion, CDA formulations are the best to take out CSCs protected by drug resistant mechanism. A major biological mission of CSCs is to repair the wound. CDA formulations are primarily made up by DIs and DHIs which are wound healing metabolites, the partners involved in the biological mission of CSCs. Naturally, DIs and DHIs are tolerable to CSCs. CDA formulations can also induce cancer cells to undergo TD to terminate malignant growth.

Hypericum patulum has been used as a folk medicine for its varied therapeutic effects including antifungal, wound-healing, spasmolytic, stimulant, hypotensive activities. The water decoction is drank as tea could treat cold, infantile malnutrition. The present study aims to isolate the constituents of the plant and investigate their effects on the glucose consumption in insulin-resistant HepG2 cells, furthermore, lipid metabolism in oleic acid (OA)-treated HepG2 cells was also studied. The phytochemical investigation of the plant led to the isolation of eleven compounds, and their structures were identified by spectroscopic analysis as n-dotriacontanol (1), shikimic acid (2), 1-O-caffeoylquinic acid methyl ester (3), 5-O-caffeoylquinic acid methyl ester (4), 5-O-coumaroylquinic acid methyl ester (5), 5-O-caffeoylquinic acid butyl ester (6), quercetin-3-O-α-L-rhamnoside (7), quercetin (8), quercetin-3-O-(4״-methoxy)-α-L-rahmnopyranosyl (9), hyperoside (10), and rutin (11). The results revealed that compounds 7, 9, and 10 could enhance glucose consumption significantly in hyperglycemia induced HepG2 cells and insulin-resistant HepG2 cells. In addition, the western blotting analysis result exhibited that compounds 7, 9, and 10 in high concentration (5 μM, H) group could dramatically upregulate the expression of PPARγ protein, and even the effect of them had no significant difference compared with that of rosiglitazone. Furthermore, compounds 9 and 10 in middle concentration (2.5 μM, M) group and H group could dramatically promote triglyceride metabolism and decrease TG content in OA-treated HepG2 cells, and even in H group, reactive oxygen species (ROS) level were significantly decreased compared with model group. PRACTICAL APPLICATIONS: Hypericum patulum is a well-known plant of the genera Hypericum for its varied preventive and therapeutic potential activities. To study the chemical constituents and their effects on glucose and lipid metabolism in vitro, we detected glucose consumption in insulin-resistant HepG2 cells, triglyceride content and reactive oxygen species level in OA-treated HepG2 cells. In addition, PPARγ protein was also detected by western blotting analysis in the study. Compounds 1, 2, 3, 5, 6, 9, 10, and 11 were isolated from the plant for the first time. Quercetin-3-O-(4"-methoxy)-α-L-rahmnopyranosyl (9) and hyperoside (10) had potential therapeutic benefit against glucose and lipid metabolic disease. Therefore, this study might have certain guiding significance for further research and development of H. patulum.

Herein, porous wollastonite ceramics with high porosity and low density were successfully fabricated with silicate tailings and electrolytic manganese slag (MS) as primary raw materials. The influences of calcination temperature, SiC and MS addition amounts on porosity, water adsorption, pore distribution, bulk density and bending strength were systematically studied. The results showed that 0.4 wt% of SiC was optimal for the ceramic foaming at the sintering temperature of 1140 ℃. The addition of MS promoted the foaming of ceramic matrix at low temperature. The porosity of ceramics reduced from 78.4–63.7%, bulk density elevated from 0.96 to 1.13 g/cm3, and bending strength increased from 8.43 to 11.22 MPa as the MS increased from 8.33 wt% to 46.67 wt%. Moreover, the best corrosion resistance performance reached to 99.55% with 8.33 wt% MS content and sintering temperature of 1160 ℃. This work is of significance for the solid waste utilization.

Introduction: Long-term diabetes may cause oculomotor nerve palsy and anxiety disorder. Diabetic oculomotor nerve palsy is usually accompanied by diplopia, ptosis and eye movement disorders. The oculomotor nerve is often separated into superior and inferior divisions; diabetic third cranial nerve palsy may affect either division in isolation. However, anxiety disorder and alternating bilateral ptosis as the first symptoms of diabetes are extremely rare. Case Presentation: This case report describes a 63-year-old female patient who was admitted to the hospital for anxiety disorder with bilateral alternating ptosis. The patient had no diplopia or other new focal neurological symptoms. A neurological examination revealed left upper eyelid ptosis; other findings were negative. Except for hyperglycemia (13.96 mmol/L) and glycated hemoglobin (7.9%), laboratory tests showed no other abnormalities. The patient eventually recovered in a short time after a comprehensive treatment, including effective blood glucose control, microcirculation improvement and anxiety management. Conclusion: The upper eyelid droop caused by long-term diabetes may result in anxiety disorder. A comprehensive treatment may be considered for the patients admitted to the hospital for diabetes and its vascular neuropathy.

A polyketide-derived alkaloid featuring a unique 3,4-dihydro-2H-indeno[1,2-b]pyridine 1-oxide motif, named phomopsol A (1), and a highly oxidized polyketide containing a new 3,5-dihydro-2H-2,5-methanobenzo[e][1,4]dioxepine moiety, named phomopsol B (2), were isolated from the Thai mangrove endophytic fungus Phomopsis sp. xy21, together with the related biosynthetic polyketide 3. The structures of 1-3 were unambiguously established by single-crystal X-ray diffraction analysis (Cu Kα), and their neuroprotective effects in PC12 cells were evaluated. The biosynthetic origins of 1-3 are proposed.

Atherosclerosis is a chronic inflammatory disease with lipid accumulation. Apolipoprotein C3 (APOC3), which is an important regulator of human lipid metabolism, is associated with multiple vascular mechanisms in atherosclerosis and proinflammatory responses. We have previously reported that the expression of inflammatory cytokine TNF-α is elevated in human endothelial cells (HUVECs) after APOC3 treatment. This study investigates the APOC3 signaling pathway involved in TNF-α-mediated expression of JAM-1 in HUVECs. Cultured HUVECs were exposed to APOC3 (50 μg/ml) for 16 h. Mechanistic studies were carried out by silencing TNF-α gene with lentiviral TNF-α-shRNA. Our study was based on the eight signaling pathway inhibitors to block the effect of APOC3 in HUVECs. The expression of JAM-1 was determined by qRT-PCR, Western blotting, and flow cytometry. IKK2 degradation and NF-κB p65 phosphorylation were determined by Western blotting. Our results showed that APOC3 significantly promoted the TNF-α-induced expression of JAM-1 in HUVECs. Inhibiting APOC3 reversed the TNF-α-induced overexpression of JAM-1. Moreover, APOC3 induced the expression of NF-κB p65 and degraded IκB. In conclusion, APOC3 promoted the expression of JAM-1 via the NF-κB, IKK2, and PI3K signaling pathway.

In this study, we report a bacterium, Achromobacter sp. TY3-4, capable of concurrently removing Mn (II) and Cr (VI) under oxic condition. TY3-4 reduced as much as 2.31 mM of Cr (VI) to Cr (III) in ...

Ascorbic acid (AA), as a key coenzyme in human metabolic pathways, plays an important role in various physiological reactions. An abnormal level of AA is found to be associated with several diseases. In this paper, we developed a label-free colorimetric method for the determination of AA by using manganese dioxide (MnO2) nanosheets. Once AA was introduced, MnO2 was reduced to Mn2+, which resulted in a remarkable color fading of MnO2 nanosheet solution. Thus, AA can be quantified by photometry in a linear range from 0.1 to 20 μM with a detection limit of 98 nM. The detection strategy possesses the advantages of versatility and low cost and shows great potential for AA detection in clinical medicine and food safety.

A bi-component supramolecular gel (RQ) was successfully constructed by the assembly of the gelators 4-aminophenyl functionalized naphthalimide derivative (R) and tri-(pyridine-4-yl)-functionalized trimesic amide (Q) in DMSO–H2O (6.1 : 3.9, v/v) binary solution. The gel RQ exhibits excellent self-healing capacity. Interestingly, the RQ could fluorescently detect and reversibly remove Hg2+ from water through cation–π interactions with high selectivity, efficient adsorption and quick response. The limit of lowest detection (LOD) of the RQ for Hg2+ is 4.52 × 10−8 M and the separation ratio is 91.14%. Moreover, the RQ could be efficiently recycled and regenerated with little loss via a simple treatment by I−. Notably, thin films based on RQ and RQ + Hg2+ were prepared, which could serve as convenient and efficient test tools for the detection of Hg2+ and I−, respectively. This work provided an efficient method and novel supramolecular gel material for the separation and detection of Hg2+.

The selective and efficient C-H methylation of sp2 and sp3 carbon centres has become a powerful transformation in the synthetic toolbox. Due to the potential for profound changes to physicochemical properties attributed to the installation of a "Magic Methyl" group at a strategic site in a lead compound, such techniques have become highly desirable in modern drug discovery and synthesis programmes. This review will cover the diverse techniques that have been employed to enable the selective installation of the C-Me bond in a wide range of chemical structures, from simple building blocks to complex drug-like architectures.

OBJECTIVE Visceral fat is thought to play different roles in the carcinogenesis of the colon with peripheral fat. Our aim was to evaluate the association of body fat distribution measured by bioelectrical impedance analysis (BIA) with the incidence of colorectal adenoma (CRA). METHODS A total of 410 asymptomatic participants who underwent a screening colonoscopy from July 2017 to December 2019 in our center were recruited, including 230 with adenomas and 180 without detected adenomas. The participants' body fat was measured by BIA, including their body fat mass (BFM), body fat percentage (BFP), and waist-to-hip ratio. Parameters of metabolic syndrome (MetS), including waist circumference, blood pressure, fasting blood glucose (FBG), blood level of triglyceride, cholesterol, and high-density lipoprotein were measured as well. RESULTS According to univariate analysis, age, male sex, body mass index, waist circumference, BFM, waist-to-hip ratio, blood pressure, and FBG were higher in the adenoma group than in the adenoma-free group (P

The fruits of Swietenia macrophylla King have been processed commercially to a variety of health foods and healthcare products and exhibited antidiabetic, anti-inflammatory, antimutagenicity, antitumor activity, and so on. This study was aimed to examine the glucose consumption in human hepatoma HepG2 cells and the expression of PPARγ of limonoids isolated from the fruits of S. macrophylla. The phytochemical investigation of the fruits led to the isolation of ten limonoids which structures were elucidated by spectroscopic analysis as swietenine (1), khayasin T (2), 6-deoxyswietenine (3), 3-O-tigloylswietenolide (4), swietenolide (5), 3,6-O,O-diacetylswietenolide (6), 7-deacetoxy-7-oxogedunin (7), fissinolide (8), proceranolide (9), 7-deacetoxy-7α-hydroxygedunin (10), and compound 10 was isolated from this plant for the first time. The glucose consumption assay revealed that compounds 1, 2, 3, 5, and 9 could promote glucose consumption significantly in normal hyperglycemia-induced HepG2 cells, furthermore, compounds 1, 5, and 9 had a better effect on promoting glucose consumption in insulin-resistant HepG2 cells. In addition, compounds 1 and 5 could dramatically enhance the expression of PPARγ protein in insulin-resistant HepG2 cells according to the western blotting analysis result. PRACTICAL APPLICATIONS: Swietenia macrophylla King belongs to the family Meliaceae and the fruits have been exhibited a wide range of biological activities, such as antidiabetic, anti-inflammatory, antimutagenicity, antitumor activity, and so on. Phytochemical investigations of S. macrophylla have revealed that limonoids and triterpenoids were effective antidiabetic agents. However, the mechanism of these limonoids to antidiabetic activity is unclear. In this study, limonoids were isolated from the fruit of S. macrophylla and their effects on the glucose consumption of insulin-resistant HepG2 cells were studied. The results showed that compounds 1 and 5 could dramatically enhance the expression of PPARγ protein in insulin-resistant HepG2 cells, which will give aid to explore the mechanism of these limonoids in the treatment of type 2 diabetes. Therefore, this research might facilitate further research and development of S. macrophylla.

Char-bound nitrogen [char(N)] is confirmed to be the real intermediate in heterogeneous reduction during coal combustion. Aiming to have a deep insight into the interaction mechanism between NO and char(N) containing different functional forms of nitrogen, a comprehensive theoretical exploration with density functional theory at M06–2X/6–31G(d,p)//def-TZVP level is performed. The detailed electronic descriptions of char(N) surface based on spin density, Mulliken atomic charge and electrostatic potential exhibit the attack sites and electron donating capability during NO chemisorption in the following order: char(N-5) N bond and promote N2 separation. The migration of oxygen atoms to adjacent active sites is thermodynamically conducive to reduction reactions, leading to the preferred pathway of N2 release on char(N-5) and char(N-X) surfaces. Contiguous active sites remaining along char edge are unfavorable for N2O detaching, while beneficial to NO further chemisorption for consecutive reactions, resulting in the great contributions of char(N-5) in reducing NO. The lower energy barriers for NO reduction follow the sequence coincident with the results of electronic property analysis. The kinetically favorable temperatures and activation energies of different char(N) for reducing NO are determined, which is consistent with previous experiments. The theoretical results provide evidences to explain microscopic mechanism of NO-char(N) interaction, making contributions to effectively minimize NOx emissions in the future.

Acceptorless dehydrogenative coupling (ADC) of alcohols and water/hydroxides is an emergent and graceful approach to produce carboxylic acids. Therefore, it is of high demand to develop active and practical catalysts/catalytic systems for this attractive transformation. Herein, we designed and fabricated a series of cyclometallated N-heterocyclic carbene-Ru (NHC-Ru) complexes via ligand tuning of [Ru-1], the superior complex in our previous work. Gratifyingly, gram-scale synthesis of carboxylic acids was efficiently enabled at an ultralow Ru loading (62.5 ppm) in open air. Moreover, effects of distinct ancillary NHC ligands and other parameters on this catalytic process were thoroughly studied, while further systematic studies were carried out to provide rationales for the activity trend of [Ru-1]-[Ru-7]. Finally, determination of quantitative green metrics illustrated that the present work exhibited superiority over representative literature reports. Hopefully, this study could provide valuable input for researchers who are engaging in metal-catalyzed ADC reactions.

In this work, pyrite was first used to precipitate arsenic in lead copper matte as the form of FeAsO4 during pressure oxidative leaching process. Initial content of arsenic in lead copper matte is of 7.92 wt%, and concentration of arsenic in leaching liquid can be less than 0.25 g·L−1 when the dosage of pyrite reaches 10 g. Leaching time, liquid-to-solid ratio, oxygen partial pressure, temperature, sulfuric acid concentration, agitation speed, and sodium lignosulfonate content were systematically studied and optimized during pressure oxidative leaching process, and the optimized conditions for pressure oxidative leaching are: leaching time 2 h, liquid-to-solid ratio 5:1, oxygen partial pressure 1.2 MPa, temperature 150 °C, sulfuric acid 200 g·L−1, agitation speed 500 r·min−1, sodium lignosulfonate 4 g. A cyclone and vertical electro-deposition method is introduced to treat the above optimized leaching solution. This method is first applied for leaching solution which is obtained from lead copper matte. After having the cyclone and vertical electro-deposition step finished, cathode copper can be greater than 99.00%.

Eight new tetramic acid derivatives, cladosporiumins A–H (1–8) were isolated from a culture broth of Cladosporium sp. SCSIO z0025 derived from the deep-sea sediment collected from Okinawa Trough. Their structures were elucidated by extensive spectroscopic data analysis. Compounds 1–3 were unique 3-acyltetramic acids with a hexyl enic alcohol side chain and a six-membered lactone ring substituted at C-3 of the 2, 4-pyrrolidinedione skeleton. The absolute configurations of chiral carbons of the 2, 4-pyrrolidinedione unit in 1–4 and 7 were established by quantum chemical calculations of the electronic circular dichroism (ECD) spectra. And the absolute configurations of chiral carbons of the six-membered lactone ring in 1–3 were established by density functional theory calculation of their 13C NMR chemical shifts. In addition, all the compounds were tested for cytotoxic, antibacterial, anti-biofilm, and AchE inhibitory activities.

The addition of exogenous substances has an important influence on soil organic matter mineralization. The aim of the present study was to investigate the effect of calcium carbonate (CaCO3) and composted manure (CM) on soil organic C (SOC) fractions and soil CO2 emission in calcareous soil. We conducted a 105-day incubation experiment involving six treatments of two soils from Yangling (Y) and Tongchuan (T) on the Loess plateau, China, which had different CaCO3 and total organic C (TOC) content. Treatments consisted of 0, 30, and 50 g kg−1 CaCO3 (Y0, Y30, Y50, T0, T30, and T50) and 0, 30, and 50 g kg−1 CaCO3 plus 20 g kg−1 CM (Y0-M, Y30-M, Y50-M, T0-M, T30-M and T50-M). Soil pH, CaCO3, CO2 emissions, TOC, microbial biomass C (MBC), dissolved organic C (DOC), readily oxidizable organic C (ROC), and bound humus (B-Hs) C were determined for each of the treatments. The application of CM increased MBC, DOC, and ROC, promoting the mineralization of SOC. However, the effects of CaCO3 addition on SOC fractions differed based on soil type and CM amendment. The addition of CaCO3 stimulated soil microbial population in the soils of Y and T. When soil was amended with CaCO3 alone, CaCO3 decreased DOC and ROC but increased B-Hs C, resulting in a reduction in soil CO2 emissions. When soil was amended with both CM and CaCO3, positive and negative net increments in soil CO2 emissions are possible, resulting in different soil cumulative CO2 emissions. These differences in interaction resulted from the priming effect of CaCO3 and CM on soil microbial community activity and the protective effect of CaCO3 on SOC. Soil CO2 emissions are determined by the combined effect of the protective effect of CaCO3 on SOM and the priming effect of soil microbes on SOC mineralization. The effect of the application of CM plus CaCO3 on SOC cycle in calcareous soils is affected by the degree of protection of SOC from SIC on the Loess plateau, China.

Limited information is available to understand the effect of biochar (BC) on soil labile organic carbon (C) and humic fractions. A laboratory incubation experiment was conducted with Lou soil (Earth-cumuli-Orthic Anthrosol) to study the influence of BCs produced at 300, 400, 500 and 600 °C (BC300, BC400, BC500 and BC600) on soil labile organic C and humic fractions, respectively. BC products were added at the rate of 2% and incubated at 25 °C over 360 days. Non-amended soil was used as the control (CK). Compared with CK, BCs amendment significantly increased the contents of soil organic C and humin by 167.51%–255.52% and 288.42%–618.11%, respectively. Microbial biomass C (MBC), dissolved organic carbon (DOC), humic acid (HA) and fulvic acid (FA) were lower in BC500 and BC600 amendment after the initial stage of incubation, while MBC, DOC and HA were higher in BC300 and BC400 amendment during the whole incubation in comparison with CK. The color tone coefficients of HA and FA increased by 6.74%, 30.87% in BC300 amendment and by 2.57%, 9.27% in BC400 amendment, while decreased by 0.32%, 5.98% in BC500 amendment and by 3.19%, 12.19% in BC600 amendment at the end of incubation as compared with CK, respectively. Compared with CK, BC300 and BC400 amendment significantly increased the ratios of HA/FA, while BC500 and BC600 amendment showed no significant difference in comparison with CK. Thus, the properties of BC should be individually characterized and the application of BC should be carefully monitored due to the positive and negative effect on soil labile organic C and humic fractions after BCs amendment.

The catalytic mechanism of Na during NO reduction on char surface is proposed to provide fundamental information for minimizing NOx emissions. A molecular modeling study was carried out using density functional theory to clarify the NO reduction and CO release pathways on char surface. The calculation results explain the promotion phenomenon caused by Na catalysis, and the fluctuation of the CO release curve in the experiment. Under H2O/Ar atmosphere, besides the NO-char heterogeneous reaction, simultaneous occurrence of the NO homogeneous reaction with lower energy barrier improved the NO reduction rate. According to the simulation results, the catalytic effect of Na is manifested in that it can weaken the conjugated components of the aromatics structure, and form a stable H-C-O-Na structure to weaken the connected C–C bond, thereby facilitating the CO release. Mayer bond order and RDG analyses indicate that the participation of Na can prevent the C-O bond from being stretched, and generate the strong attractive interaction to promote the NO reduction.

Nanomaterials with intrinsic enzyme-like activities have attracted extensive research interest as promising alternatives to natural biological enzymes due to their advantages of low cost and high stability. Many artificial enzyme mimics have been successfully applied in the fields of sensing, environmental treatment, and oncotherapy. Herein, novel palygorskite@Co3O4 nanocomposites (Pal@Co3O4 NCs) were fabricated by modifying Pal with Co3O4 nanoparticles through a facile hydrothermal method. The obtained Pal@Co3O4 nanocomposites as nanozymes displayed enhanced peroxidase-like activity, which can catalyze the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H2O2) to obtain colored products. Kinetic assay indicated that the Pal@Co3O4 peroxidase mimics showed a higher affinity towards TMB than that of natural horseradish peroxidase (HRP). Moreover, a sensitive and selective sensor for colorimetric determination of H2O2 and ascorbic acid (AA) was successfully constructed by using Pal@Co3O4 nanocomposites as peroxidase mimics. Furthermore, the proposed assay for sensing of AA in model samples was evaluated with satisfactory results, demonstrating the potential applications in complex biological systems.

Two new metal–organic frameworks (MOFs) based on cadmium(II) ions, 1,2-benzenedicarboxylic acid (BDC), flexible ligand 1,4-bi(1H-imidazol-1-yl)butane (BIIM), coordinated water molecules, [(BIIM)(BDC)(H2O)Cd]3n (1) and copper(II) ions, BIIM, coordinated water, free thiophene-2,5-dicarboxylate (TDC), free water, {[(BIIM)4(H2O)4Cu2]·(TDC)2·(H2O)12}n (2) are prepared and characterized by X-ray diffraction, thermal gravimetric analysis (TGA), infrared (IR) spectrum and the photoluminescence property for complex (1). The X-ray diffraction analysis reveals that the structures of complexes 1 and 2 are 2D structures through the C–H···π stacking interactions (for 1) and the BIIM bridging connections (for 2). The IR spectrum for 1 and 2 are presented in the paper, for 1, the strong peaks at 1399 and 1573 cm−1 are owing to the carboxylic CO2 − symmetry and asymmetry stretching vibrations of BDC. The features of the IR spectrum are consistent with the single crystal structures. The TGA reveal the water is the first lost material from complex, then the ligands removed, and finally the residues of these two complexes are the metal oxide.

// Chao-Huan Xu 1 , Zhong-Hui He 1 and Hong Xu 1 1 Department of Gynaecology, First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China Correspondence to: Hong Xu, email: nnxuhong@163.com Keywords: vascular endothelial growth factor, polymorphism, ovarian cancer, meta-analysis Received: May 14, 2017 Accepted: August 09, 2017 Published: August 21, 2017 ABSTRACT This study meta-analyzed the literature on possible association of four polymorphisms (+936C/T, −460C/T, −2578C/A and −1154G/A) in the vascular endothelial growth factor (VEGF)-A gene with risk of ovarian cancer. Meta-analysis of 7 case-control studies involving +936C/T, 4 studies involving −460C/T, 4 studies involving −2578C/A and 2 studies involving −1154G/A showed significant association between −460C/T and ovarian cancer risk. This risk was observed in the total population (allelic model, OR 1.80, 95% CI 1.26–2.59, P = 0.001; recessive model, OR 1.84, 95% CI 1.13–2.98, P = 0.01; dominant model, OR 0.51, 95% CI 0.39–0.67, P < 0.001; homozygous model, OR 2.48, 95% CI 1.72–3.56, P < 0.001; heterozygous model, OR 1.67, 95% CI 1.26–2.21, P < 0.001) and in the subgroup of Asian study participants. The CA genotype at −2578C/A was a risk factor in the total population, while the CT genotype at +936C/T was a protective factor in Caucasians. None of the five genetic models suggested a significant association between −1154G/A and ovarian cancer risk in the entire study population, or between +936C/T and risk in Asian or Chinese participants. These findings should be verified in large, well-designed studies.

A new linear peptide simplicilliumtide I (1) and four new cyclic peptides simplicilliumtides J–M (2–5) together with known analogues verlamelins A and B (6 and 7) were isolated from the deep-sea-derived fungal strain Simplicillium obclavatum EIODSF 020. Their structures were elucidated by spectroscopic analysis, and their absolute configurations were further confirmed by chemical structural modification, Marfey’s and Mosher’s methods. Compounds 2, 6, and 7 showed significant antifungal activity toward Aspergillus versicolor and Curvularia australiensis and also had obvious antiviral activity toward HSV-1 with IC50 values of 14.0, 16.7, and 15.6 μM, respectively. The structure–bioactivity relationship of this type of cyclic peptide was also discussed. This is the first time to discuss the effects of the lactone linkage and the substituent group of the fatty acid chain fragment on the bioactivity of this type of cyclic peptides. This is also the first time to report the antiviral activity of these cyclic pe...

Several chiral phosphoric acids were evaluated as organocatalysts for the enantioselective Biginelli reaction of aliphatic aldehydes. With a chiral phosphoric acid derived from 3,3′-bis(3,5-di-tert-butyl-4-methoxyphenyl)-1,1′-binaphthalene-2,2′-diol, and after extensive optimization of the reaction conditions, the corresponding dihydropyrimidines were obtained in moderate to high yields with 73–87% ee by a three-component reaction of an aliphatic aldehyde, urea, and a β-keto ester.

Background VEGFR-2 inhibitors have been widely used in the treatment of cancer. In our continued efforts to search for potent and novel VEGFR-2 inhibitors as antitumor agents, we have identified a series of ureas and amides bearing a oxazolopyrimidine scaffold. Aim of the Study To discover more potent VEGFR-2 inhibitors with stronger binding affinity and better physical and chemical properties. Methods 23 pyrimidinylacetamide-based ureas were designed and synthesized. Replacement of oxazolopyrimidine with a pyrimidinylacetamide generated a series of novel VEGFR-2 inhibitors. Results and Conclusions In HUVEC inhibition assay, the most potent compound (compound 16) possessed an IC 50 value of 0.43 μM. Compound 16 also inhibited the migration and capillary like tube formation of HUVECs with inhibition rate at 22% (1 μM) and 17.5% (0.8 μM) respectively. These results support the further investigation of compound 16 as a potential anti-cancer agent.