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A novel separator constructed by coating a layer of perovskite lithium lanthanum titanate (LLTO)/Super P (SP) composite over a commercial PE membrane was employed for the first time in the Li-S battery (LLTO@Li-S). It was found that the LLTO@Li-S battery possessed an obviously lower impedance but higher Li-ion diffusion than the Li-S battery employing the uncoated separator (Pristine@Li-S). This enabled the soluble polysulfides to be effectively immobilized and further electrochemically transformed into Li₂S via the formation of thiosulfate/polythionate intermediates over the LLTO/SP-coated separator during the discharge of the battery. As a result, the shuttle effect was effectively inhibited, and particularly the passivation of both the cathode and “dead S” over the separator was largely decreased. These properties ensured that the LLTO@Li-S battery displayed a significantly high specific capacity and rate capability as well as good cycling stability. For the LLTO@Li-S battery with a S loading of 2 mg cm–², an initial specific capacity of 1491 mAh g–¹ at 0.1C and a residual specific capacity of 459 mAh g–¹ at 1C after 1200 cycles had been achieved, while for the LLTO@Li-S battery with a S loading of 5 mg cm –², an initial specific capacity of 1046 mAh g –¹ and a residual specific capacity of more than 800 mAh g–¹ at 0.1C after 50 cycles could be delivered. more...

Heterogeneous catalytic reactions based on single metal–organic framework (MOF) material for the oxidative carboxylation of olefins following a tandem process, which involves the epoxidation of olefins and subsequent epoxide–CO2 cycloaddition, are highly desirable and economical for CO2 chemical fixation. In this work, a new trans-A2B2-type porphyrin ligand, 5,15-di(m-benzoato)-porphyrin (H2DMBP), was successfully synthesized and utilized for constructing a novel, highly porous, and stable Nd-porphyrin MOF, named CSUST-2. (CSUST stands for Changsha University of Science and Technology.) Furthermore, the coordinatively unsaturated Co(II) ions were implanted into the MOF by exploiting the innate non-metallated porphyrin ligands to generate Co(II)@CSUST-2 framework, which was evidenced to act as an efficient recyclable catalyst for oxidative carboxylation of olefins in the presence of tert-butyl hydroperoxide (TBHP) as an oxidant and tetrabutylammonium bromide (n-Bu4NBr) as a co-catalyst under mild conditions (1 atm CO2, 75 °C, and without solvent). more...

Cerium (IV)-based metal-organic frameworks (MOFs) are highly desirable due to their unique potential in fields such as redox catalysis and photocatalysis. However, due to the high reduction potential of Ce(IV) species in solution, it is still a great challenge to synthesize Ce(IV)-MOFs with novel structures, which are extremely dominated by the hexanuclear Ce-O cluster inorganic building units (IBUs). Herein, a Ce-O chain IBU containing Ce(IV)-MOF CSUST-3 (CSUST: Changsha University of Science and Technology) was successfully prepared guided by the kinetic stabilization study of UiO-66(Ce)-NDC (H 2 NDC = 2,6-naphthalenedicarboxylic acid). Furthermore, owing to the superior redox activity, Lewis acidity and semiconductor-like behavior incurred by Ce 4+ , activated CSUST-3 was demonstrated to be an excellent catalyst for CO 2 chemical fixation by virtue of one-pot synthesis of styrene carbonate from styrene and CO 2 under mild conditions (1 atm CO 2 , 80 °C, and solvent-free), as well as to be a remarkable co-catalyst-free photocatalyst for overall water splitting (OWS), which exhibits 59 μmol∙g -1 ∙h -1 of H 2 and 22 μmol∙g -1 ∙h -1 of O 2 under simulated sunlight irradiation (Na 2 S-Na 2 SO 3 as sacrificial agent). more...

Rapamycin is known to inhibit the mammalian target of rapamycin complex (mTORC)1 signaling pathway, but it is unable to effectively inhibit mTORC2, resulting in activation of protein kinase B in multiple myeloma (MM) cell lines. Additionally, certain studies have suggested that resveratrol has an effect on human MM cells, and that rapamycin in combination with resveratrol may be useful in cancer therapy. The present study aimed to investigate the combined treatment effect of resveratrol and rapamycin on the MM MM1.S cell line. The results demonstrated that combined treatment with rapamycin and resveratrol effectively inhibited cell viability in the MM1.S cell line through inhibition of the mTORC1 and mTORC2 signaling pathways, compared with resveratrol or rapamycin monotherapy. In addition, cyclin D1 levels were decreased and the activation of caspase-3 and poly (ADP-ribose) polymerase was increased. These results suggested that downregulation of the mTOR signaling cascades is likely to be a crucial mediator in the impairment of viability and the induction of apoptosis resulting from combined therapy with resveratrol and rapamycin in MM1.S cells. more...

Progressive diabetic nephropathy (DN) in diabetes leads to major morbidity and mortality. The major pathological alterations of DN include mesangial expansion, extracellular matrix alterations, tubulointerstitial fibrosis, and glomerular sclerosis. Polygoni avicularis is widely used in traditional oriental medicine and has long been used as a diuretic, astringent, insecticide and antihypertensive. However, to the best of the authors’ knowledge, the effects of the ethanolic extract from rhizome of Polygoni avicularis (ER-PA) on DN have not yet been assessed. The present study aimed to identify the effect of ER-PA on renal dysfunction, which has been implicated in DN in human renal mesangial cells and db/db mice and investigate its mechanism of action. The in vivo experiment was performed using Polygoni avicularis-ethanol soluble fraction (ER-PA) and was administrated to db/db mice at 10 and 50 mg/kg dose. For the in vitro experiments, the human renal mesangial cells were induced by high glucose (HG, 25 mM). The ER-PA group showed significant amelioration in oral glucose tolerance, and insulin resistance index. ER-PA significantly improved the albumin excretion and markedly reduced plasma creatinine, kidney injury molecule-1 and C-reactive protein. In addition, ER-PA significantly suppressed inflammatory cytokines. Histopathologically, ER-PA attenuated glomerular expansion and tubular fibrosis in db/db mice. Furthermore, ER-PA suppressed the expression of renal fibrosis biomarkers (TGF and Collagen IV). ER-PA also reduced the NLR family pyrin domain containing 3 inflammatory factor level. These results suggest that ER-PA has a protective effect against renal dysfunction through improved insulin resistance as well as the inhibition of nephritis and fibrosis in DN. more...

Since the discovery of liquid-phase-exfoliated black phosphorus (BP) as a field-effect transistor in 2014, BP, with its 2D layered structure, has attracted significant attention, owing to its anisotropic electroconductivity, tunable direct bandgap, extraordinary surface activity, moderate switching ratio, high hole mobility, good biocompatibility, and biodegradability. Several pioneering research efforts have explored the application of BP in different types of electrochemical sensors. This review summarizes the latest synthesis methods, protection strategies, and electrochemical sensing applications of BP and its derivatives. The typical synthesis methods for BP-based crystals, nanosheets, and quantum dots are discussed in detail; the degradation of BP under ambient conditions is introduced; and state-of-the-art protection methodologies for enhancing BP stability are explored. Various electrochemical sensing applications, including chemically modified electrodes, electrochemiluminescence sensors, enzyme electrodes, electrochemical aptasensors, electrochemical immunosensors, and ion-selective electrodes are discussed in detail, along with the mechanisms of BP functionalization, sensing strategies, and sensing properties. Finally, the major challenges in this field are outlined and future research avenues for BP-based electrochemical sensors are highlighted. more...

Via induction of achiral aromatic solvents, two 3-D monochiral 3d–4f MOFs (1 and 2) from the ligand HIN without any chiral auxiliary are uncommonly constructed. The results show that the homochiral compounds 1 and 2 are enantiopure rather than exhibiting enantiomeric excess. Obviously, this work has brought major synthetic advancement in homochiral framework materials of great significance. more...

This study gives the influence laws of abandoned channel, in-layer interlayer, sand body contact relationship on the development effect of the Alkaline Surfactant Polymer (ASP) flooding based on the data of the industry promotion block ( Pu I32、Pu I33 sedimentation), and give out corresponding adjustment strategy at the same time. The result shows that: The ‘abruptly abandoned’ channels have a bad connection with the main channel and possesses a far lower reservoir producing degree (16.1%) than the ‘gradually-abandoned’ channels (79.9%). The injection wells located upon the channel sand need high concentration inject fluid with lower injection rate to handle the polymer breakthrough; The injection wells located between the channels need lower concentration injection; The injection wells located upon the abandoned channels firstly need high concentration injection to achieve the profile control and then inject low concentration fluid to adjust low permeable sublayer; The production wells located upon abandoned channels need timely fracturing measures. By July 2014, water content of this area is 90.7%, oil recovery improved 18.08% and is expected to reach 22.0%. Similar the success experience we get from this area can guide the study of block geologic factors that affect development result and has important guiding significance to the implementation of pointed development adjustment. more...

Glomerular fibrosis is caused by an accumulation of intercellular spaces containing mesangial matrix proteins through either diffused or nodular changes. Dianthus superbus has been used in traditional medicine as a diuretic, a contraceptive, and an anti-inflammatory agent. The aim of this study was to investigate the effects of Dianthus superbus-EtOAc soluble fraction (DS-EA) on glomerular fibrosis and renal dysfunction, which has been implicated in diabetic nephropathy in human renal mesangial cells and db/db mice. DS-EA was administered to db/db mice at 10 or 50 mg/kg/day for 8 weeks. DS-EA treatment significantly ameliorated blood glucose, insulin, the homeostasis model assessment of insulin resistance (HOMA-IR) index, and HbA1c in diabetic mice. DS-EA decreased albumin excretion, creatinine clearance (Ccr), and plasma creatinine levels. DS-EA also ameliorated the levels of kidney injury molecules-1 (KIM-1) and C-reactive protein. DS-EA reduced the periodic acid-Schiff (PAS) staining intensity and basement membrane thickening in glomeruli of the diabetic nephropathy model. In addition, DS-EA suppressed transforming growth factor-&beta, (TGF-&beta, )/Smad signaling. Collagen type IV, a glomerular fibrosis biomarker, was significantly decreased upon DS-EA administration. DS-EA pretreatment attenuated levels of inflammation factors such as intracellular cell adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein-1 (MCP-1). DS-EA inhibited the translocation of nuclear factor kappa B (NF-&kappa, B) in Angiotensin II (Ang II)-stimulated mesangial cells. These findings suggest that DS-EA has a protective effect against renal inflammation and fibrosis. Therefore, DS-EA may serve as a potential therapeutic agent targeting glomerulonephritis and glomerulosclerosis, which lead to diabetic nephropathy. more...

Development of a facile but high-efficient small organic molecule-based photothermal therapy (PTT) in the in vivo transparent window (800–900 nm) has been regarded as a minimally invasive and most promising strategy for potential clinical cancer treatment. Phthalocyanine (Pc) molecules with remarkable photophysical and photochemical properties as well as high extinction coefficients in the near-infrared region are highly desirable for PTT, but as far satisfying single-component Pc-based PTT within the in vivo transparent window (800–900 nm) has very rarely been reported. Herein, inspired by the self-assembly algorithm of natural bacteriochlorophylls c, d, and e, biomimetic self-assembling tetrahexanoyl Pc Bio-ZnPc with outstanding light-harvesting capacity was demonstrated to exhibit excellent PTT efficacy evidenced by both in vitro and in vivo results, within the biological transparent window. more...

International audience; We synthesized a series of biomimetic self-assembling phthalocya-nines equipped with carbonyl groups as recognition motifs, a central zinc atom and diverse solubilizing alkyl chains mimicking for the first time with these robust pigments the natural chlorosomal bacterio-chlorophylls. Upon self-assembly a very broad and red-shifted Q-band absorption extending to over 900 nm is put into evidence. more...

Titania/electro-reduced graphene oxide nanohybrids (TiO2/ErGO) were synthesized by the hydrolysis of titanium sulfate in graphene oxide suspension and in situ electrochemical reduction. It provides a facile and efficient method to obtain nanohybrids with TiO2 nanoparticles (TiO2 NPs) uniformly coated by graphene nanoflakes. TiO2/ErGO nanohybrids were characterized by transmission electron microscopy, X-ray diffraction, cyclic voltammogram, and electrochemical impedance spectroscopy in detail. Compared with pure ErGO and TiO2 NPs, TiO2/ErGO nanohybrids greatly enhanced the electrocatalytic activity and voltammetric response of Allura Red. In the concentration range of 0.5&ndash, 5.0 &mu, M, the anodic peak currents of Allura Red were linearly correlated to their concentrations. However, the linear relationship was changed to the semi-logarithmic relationship at a higher concentration region (5.0&ndash, 800 &mu, M). The detection limit (LOD) was 0.05 &mu, M at a signal-to-noise ratio of 3. The superior sensing performances of the proposed sensor can be ascribed to the synergistic effect between TiO2 NPs and ErGO, which provides a favorable microenvironment for the electrochemical oxidation of Allura Red. The proposed TiO2/ErGO/GCE showed good reproducibility and stability both in determination and in storage, and it can accurately detect the concentration of Allura Red in milk drinks, providing an efficient platform for the sensitive determination of Allura Red with high reliability, simplicity, and rapidness. more...

Two new complexes based on 4-(benzimidazol-1-ylmethyl)benzoic acid (HL), (Sm2L6·H2O)n (1) and (LuL3)n (2), have been synthesized under the solvothermal condition and characterized by single-crystal X-ray diffraction, X-ray powder diffraction (PXRD), thermogravimetric analysis (TGA) and elemental analysis (EA) and IR spectra. The results show that both complexes are isomorphous and possess 2-D pillar-chained frameworks, consisting of 1-D triple-stranded double-helical (PPM/MMP) [Ln(η2-O)(μ2-OCO)2]n (Ln = Sm(1), Lu(2)) motif as chain and μ3-(η1:η1:η1)-bridging ligand L− as pillar, though they have different space groups of triclinic P-1 for 1 and monoclinic P21/c for 2. Two complexes represent the first example of 2-D lanthanide compound containing 4-(benzimidazol-1-ylmethyl)benzoic acid as the sole ligand. Additionally, the photoluminescent property of 1 is also discussed. more...

Three isostructural lanthanide complexes, [Ln2(H2O)4(DMSO)](CuI)4(Ina)4(ox)[HIna = isonicotinic acid; H2ox = oxalic acid; Ln = Pr(1), Sm(2), Eu(3)], have been synthesized under the solvothermal condition and characterized by single-crystal X-ray diffraction, X-ray powder diffraction (PXRD), thermogravimetric analysis (TGA) and elemental analysis (EA) and IR spectra. Complexes 1–3 present 2-D pillar-chained frameworks and consist of two distinct chain-like motifs of inorganic [Cu4I4]n cluster chains and organic Ln-carboxyl-oxalic [Ln2(μ2-Ina)2(Ina)2(μ2-ox)]n chains. The 13C NMR of HIna indicates ox2 − in 1–3 is generated by the in situ decomposition of HIna. Additionally, the photoluminescent properties of 1–3 are also discussed. more...

Ethnopharmacological relevance The root barks of Morus alba have been used in traditional medicine as an anti-inflammatory drug, especially for treating lung inflammatory disorders. Aim of study To find new alternative agents against airway inflammation and to establish the scientific rationale of the herbal medicine in clinical use, the root barks of Morus alba and its flavonoid constituents were examined for the first time for their pharmacological activity against lung inflammation. Materials and methods For in vivo evaluation, an animal model of lipopolysaccharide-induced airway inflammation in mice was used. An inhibitory action against the production of proinflammatory molecules in lung epithelial cells and lung macrophages was examined. Results Against lipopolysaccharide-induced airway inflammation, the ethanol extract of the root barks of Morus alba clearly inhibited bronchitis-like symptoms, as determined by TNF-α production, inflammatory cells infiltration and histological observation at 200–400 mg/kg/day by oral administration. In addition, Morus alba and their major flavonoid constituents including kuwanone E, kuwanone G and norartocarpanone significantly inhibited IL-6 production in lung epithelial cells (A549) and NO production in lung macrophages (MH-S). Conclusions Taken together, it is concluded that Morus alba and the major prenylated flavonoid constituents have a potential for new agents to control lung inflammation including bronchitis. more...

One new 3-D PbII complex, {[Pb2(tza)(μ3-OH)(μ3-Cl)(μ4-Cl)]n (1) (Htza = tetrazole-1-acetic acid), has been synthesized from the reaction of tetrazole-1-acetic acid (Htza) with PbCl2 at pH = 8.5 under hydro-solvent condition and characterized by X-ray single crystal diffraction, elemental analysis, thermogravimetric analysis, and IR spectra. The results show that the coordination chemistry of the multi-dentate ligand Htza on PbII ion has good pH sensitivity. At pH = 5 and 7, two once reported 3-D framework complexes {[Pb(tza)2]n (2) and [Pb(tza)(μ3-Cl)]n (3) are obtained, respectively. And then at pH = 8.5, the resultant three-dimensional complex 1 presents the pillar-layer framework network with a thickness of 8.25 A of layer [Pb2(μ3-OH)(μ2-O)2(μ3-Cl)(μ4-Cl)]n, in which there still exists the μ3-bridging mode of OH− group and the μ2-carboxyl oxygen atom besides the μ3- and μ4-bridging manners of the Cl− ion. Furthermore, the luminescent property of complex 1 has also been investigated, and the result exhibits blue photoluminescence in the solid state at room temperature, which shows that this complex may be a good candidate for photoactive material. more...

A new triterpenoid, named alisol Q 23-acetate, as well as fourteen known terpenes, alisol B 23-acetate (2), alisol B (3), alismol (4), 10-O-methyl-alismoxide (5), alismoxide (6), 11-deoxyalisol C (7), 13β,17β-epoxyalisol B 23-acetate (8), 4β,12-dihydroxyguaian-6,10-diene (9), alisol C 23-acetate (10), alisolide (11), 16β-methoxyalisol B monoacetate (12), alisol A (13), 16β-hydroxyalisol B 23-acetate (14), alisol A 24-acetate (15) were isolated from the rhizomes of Alisma orientale. The structures of compounds (1-15) were identified based on 1D and 2D NMR, including (1)H-(1)H COSY, HSQC, HMBC and NOESY spectroscopic analyses. Among these isolates, antibacterial effect of compounds 2, 3, 10, and 15, major constituents of A. orientale was examined. The MIC values of compounds 2, 10, and 15 were 5-10 βg/mL against eight antibiotic resistant strains, which were lower than those from the positive controls (MICs of chloramphenicol and ampicillin were 5-80 μg/mL). Therefore, compounds 2, 10 and 15 exhibited the potent antibacterial activity. more...

The reaction of pyridine-2,3-dicarboxylic acid (2,3-pydcH2) with CuI and Ln2O3 under hydrothermal conditions generated a series of new one-, two-, and three-dimensional coordination polymers, namely, {[Cu3Ln2(2,3-pydc)6(H2O)12]·12H2O}n [Ln = La(1), Nd(2)], {[Cu3Ln2(2,3-pydc)6(H2O)8]·6H2O}n [Ln = Sm(3), Gd(4)], and {[Cu3Ln2(2,3-pydc)6(H2O)10]·10H2O}n [Ln = Tb(5), Ho(6), Er(7), Yb(8), Lu(9)]. The results show that compounds 1 and 2 (type I structure) are 1-D Cu-4f rhombic lattice chains that are formed through assembly of two building block units Cu3(pydc)6 and Ln(H2O)6. Compounds 3–4 (type II structure) are 2-D layers that are constructed from building block units [Cu(pydc)2(H2O)2] μ2-bridging adjacent 1-D rhombic lattice chains –[(Cu2(pydc)4)-(La(H2O)4)]n–. Complexes 5–9 (type III structure) are also isomorphous and have the same 3-D network structures with 1-D channels along the c axis, and are formed by assembly of building block units Cu3(pydc)6 with Ln(H2O)5. The progressive structural variation from the 1-D chains 1–2 to 2-D layers 3–4 and to 3-D frameworks 5–9 is attributed to the lanthanide contraction effect and to the different coordination modes of 2,3-pydc2–. The N2 gas adsorption and fluorescent properties of the partial complexes were also investigated. more...

article i nfo Article history: Three lanthanide metal organic frameworks (MOFs) with mixed carboxylates of 5-aminoisophthalic acid (H2AIP) and oxalic acid (H2OX), namely (Yb(AIP)(OX)0.5(H2O)3)n·H2 O( 1), (Tb(HAIP)(OX)(H2O))n (2), and {(Er(AIP)(OX)0.5(H2O))·H2O}n (3) were obtained by hydrothermal reactions and characterized by elemental analysis, IR spectra and thermogravimetric analysis, as well as single crystal X-ray diffraction. These frame- works exhibit three typical structural features: complex 1 possesses one-dimensional ladder-like chain, 2 has two-dimensional layer, and 3 is three-dimensional framework. Moreover, the fluorescent property of 2 is also investigated. © 2012 Published by Elsevier B.V. more...

A new megastigmane palmitate, 9-oxomegastigm-5(13)-ene-2β-palmitate (1), and a new oleanane triterpenoid, (3β)-3,23,28-trihydroxyolean-12-en-11-one (2), together with three known oleanane-type triterpenoids, β-amyrin (3), erythrodiol (4), and (3β)-olean-12-ene-3,23,28-triol (5), were isolated from the aerial parts of Aster yomena (Asteraceae). Their structures were identified based on 1D- and 2D-NMR analysis, including 1H,1H-COSY, HSQC, HMBC, and NOESY techniques. more...

A new 2D Dysprosium compound [Dy(3,4-qldc)(ox)0.5(H2O)2]n (1) (3,4-H2qldc = 3,4-Quinolinedicarboxylic acid) has been successfully constructed by the hydrothermal reaction of Dy(NO3)3 with 3,4-H2qldc, and characterized by elemental analysis, IR spectroscopy and thermogravimetric analysis, as well as single-crystal X-ray diffraction. The results reveal that complex 1 possesses a 2-D framework with 44 topology constructed from one-dimensional lanthanide-3,4-qldc zigzag chains and oxalate pillars. To the best of our knowledge, complex 1 represents the first example of the coordination compound containing 3,4-H2qldc as the multi-functional ligand. Moreover, compound 1 displays a certain photoluminescent property and high thermal stability. more...

A new 2D cadmium compound [Cd(2,4′-bpdc)H2O]n ( 1 ) (2,4′-H2bpdc = 2,4′-biphenyldicarboxylic acid) has been successfully synthesized by the hydrothermal reaction of Cd(Ac)2 and 2,4′-H2bpdc, and characterized by element analysis, IR spectroscopy and thermal analysis, as well as single-crystal X-ray diffraction. The results reveal that complex 1 possesses a 2D framework with one-dimensional nano-channels hinged by two meso-helical chains sharing two Cd centers through 2,4′-bpdc2− ligands, which denotes the first example of the complex including single 2,4′-biphenyldicarboxylate ligand. Moreover, compound 1 displays a strong photoluminescent property and high thermal stability. more...

Five compounds, styraxjaponoside A (1), matairesinoside (2), egonol glucoside (3), dihydrodehydrodiconiferyl alcohol 9'-O-glucoside (4), and styraxjaponoside B (5) were isolated from the stem bark of Styrax japonica. Among them, compounds 1 and 5 showed significantly high virus-cell fusion inhibitory activity. In addition, compound 5 exhibited almost equivalent virus-cell fusion inhibitory activity to that of dextran sulfate, which is used as a positive control. more...

To further investigate anticonvulsant activity of quinoline derivatives, a series of 7-alkoxy-4,5-dihydro-[1,2,4]triazolo[4,3- a ]quinoline-1(2 H )-one derivatives was synthesized starting from 7-hydroxyl-3,4-dihydro-2(1 H )-quinoline. In initial (phase I) screening and quantitative (phase II) evaluation, compound 7-benzyloxyl-4,5-dihydro-[1,2,4]thiazolo[4,3- a ]quinoline-1(2 H )-one ( 3f ) was among the most active but also has the lowest toxicity. In the anti-MES potency test, it showed median effective dose (ED 50 ) of 12.3 mg/kg, median toxicity dose (TD 50 ) of 547.5 mg/kg, and the protective index (PI) of 44.5, which is much greater than PI of the prototype drugs phenytoin, phenobarbital, carbamazepin, and valproate. Compound 3f was chosen for further evaluation. In phase III pharmacological test, the compound had median hypnotic dose (HD 50 ) and median lethal dose (LD 50 ) of 1204 mg/kg and >3000 mg/kg, respectively, thus demonstrating much greater margin of safety compared to prototype drugs. The compound 3f also showed significant oral activity against MES-induced seizures and low oral neurotoxicity in mice in phase IV pharmacological test. Possible structure–activity relationship was discussed. more...

A bioassay-guided fractionation of the CH(2)Cl(2) extract of Selaginella tamariscina yielded six sterols 1-6 such as (4α, 5α)-4, 14-dimethylcholest-8-en-3-one (1), ergosta-4, 6, 8(14), 22-tetraene-3-one (2), ergosterol endoperoxide (3), 7β-hydroxycholesterol (4), 7β-hydroxysitosterol (5), and 7α-hydroxysitosterol (6). The structures of isolated compounds were determined using spectroscopic methods. Among these isolates, compounds 2-5 showed potent cytotoxicity against five human tumor cells, while compounds 1 and 6 did not. In the case of compounds 1 and 2, 3-oxo sterol derivatives, compound 1 was inactive, but compound 2 showed potent cytotoxicity. In addition, compound 5 exhibited potent cytotxicity, but, compound 6 which is the 7-epimer of compound 5 was weakly active against tumor cell lines. Therefore, in the case of oxysterol derivatives, the cytotoxicity appeared to be affected by the structural differences, i.e. the configuration of hydroxyl group and the number of conjugated double bond. Taken all together, the present study isolated six sterols from S. tamariscina for the first time based on a bioassay-guided fractionation and indicated that isolated oxysterols could exhibit the cytotoxic effects against tumor cells, suggesting that S. tamariscina might be a promising candidate for the development of anticancer agents. more...

At low temperature, the reactions of quinoline-2,3-dicarboxylic acid (2,3-H2qldc) with ZnCl2 in three different solvents gave three 0-D mononuclear compounds respectively, namely Zn(2,3-Hqldc)2(H2O)2 (1), Zn(2,3-Hqldc)2(DMSO)2 (2) and Zn(2,3-Hqldc)2(H2O)2·C6H6 (3). At high temperature, the three corresponding reactions always produced 2-D 44 topological layer [Zn(2,3-Hqldc)2]n (4). Interestingly, compound 4 may also be constructed through the temperature-driven irreversible change in solution from 1, 2 and 3. Supramolecular structure analyses reveal that through hydrogen bonding interactions, such as O–H⋯O/C–H⋯O)/C–H⋯π/π⋯π, the mononuclear units Zn(2,3-Hqldc)2(H2O)2 (1), Zn(2,3-Hqldc)2(DMSO)2 (2) and Zn(2,3-Hqldc)2(H2O)2·C6H6 (3) as well as the 2-D layer [Zn(2,3-Hqldc)2]n (4) were further assembled into 3-D 412·63 (in 1 and 4) and 3-D 424·64 (in 2 and 3) supramolecular networks, respectively. Obviously, these results show that the reaction temperature and solvent play critical roles in directing the molecular structures and supramolecular assemblies of these low-dimensional zinc(II) compounds. more...