Palladium-Catalyzed Dual C-H Carbonylation of Diarylamines Leading to Diversified Acridones under CO-Free Conditions.

A Pd-catalyzed dual C-H carbonylation of commercially available diarylamines using Co2(CO)8 as a safe CO source has been developed. This methodology provides a facile approach for the synthesis of diversified acridones in moderate to good yields. The protocol features good functional group compatibility, operational safety, easy scale-up, and versatile transformations.

Palladium-Catalyzed Carbonylative Dearomatization of Indoles to Achieve Carbonyl-Containing Spirocyclic Indolenines Bearing an All-Carbon Quaternary Center.

A Pd-catalyzed carbonylative dearomatization via an acyl Pd complex has been developed. Diversified carbonyl-containing spirocyclic indolenines with an all-carbon quaternary center were constructed in an efficient and straightforward way with good to excellent yields. The protocol features a simple catalytic system, operational simplicity, a broad substrate scope, easy scale-up, and versatile transformations. In addition, the asymmetric reaction was initially explored with moderate enantioselectivity.

Palladium-Catalyzed Dearomatization of Indoles with Alkynes: Construction of Spirocyclohexaneindolenines.

A palladium-catalyzed dearomatization of indoles with alkynes has been developed, providing an efficient route to access a variety of synthetically useful spirocyclohexaneindolenines in moderate to good yields. The current method features a simple catalytic system, operational simplicity, and good functional group compatibility, which will contribute substantially to the development of dearomatization to access spiro compounds. Besides, the ubiquitous existence of spiro molecules, including spirocyclohexaneindolenines, in drugs and biological active molecules suggests the potential application of this methodology in medicinal chemistry.

[Textual research on origin and genuine of Lilii Bulbus].

Lilii Bulbus, which comes from many medicinal plants，is a frequently-used traditional Chinese medicine，the records in previous herbal literatures of it's origin and quality were inconstant. To trace back it's sources, we conducted a systematical study on it's origin and quality by textual research and investigation in this paper,The result showed that the origins of Lilii Bulbus are mainly source from white-flowers, red-yellow-flowers and red-flowers of Lilium， L. brownii var. viridulum, which were believed authentic or good quality in all previous herbal literatures,and L. pumilum and L. concolor which belong to white-flowers,and L. lancifolium which belong to red-yellow-flowers were believed low-quality and unfit for medicinal uses, or they were listed below and often have different effect with L. brownii var. viridulum. Among them, only L. concolor does not belong to Lilii Bulbus according to Chinese Pharmacopeia (2015 edition), The mainstream varieties of Lilii Bulbus became L. lancifolium now according to our practical investigation, which were very different from previous herbal literatures. Although chemical and pharmacological studies provided a reference for L. lancifolium，we should respect the actual records of the previous herbal literatures，the research of material foundation of efficacy should be more sufficient，and provide science evidence for clinical application of different species of Lilii Bulbus.

Metabolism, Distribution, and Elimination of Mequindox in Pigs, Chickens, and Rats.

Mequindox (MEQ), a quinoxaline-N,N-dioxide antibacterial agent used to control bacterial enteritis in various food-producing animals, is a potential violative residue in food animal-derived products. The disposition and elimination of MEQ in rats, pigs, and chickens was comprehensively investigated to identify the marker residue and target tissue of MEQ in food animals for residue monitoring. Following a single oral administration, 62-71% of MEQ was rapidly excreted via urine and feces in all species within 24 h. Urinary excretion of radioactivity was 84 and 83.5% of the administered dose in rats and pigs, respectively. More than 92% of the administered dose was excreted in all species within 15 days. Radioactivity was found in nearly all tissues at the first 6 h after dosing, with the majority of radioactivity cleared within 4-6 days. The highest radioactivity and longest persisting time were found to be in the liver and kidney. Totals of 11, 12, and 7 metabolites were identified in rats, chickens, and pigs, respectively. No parent drug could be detected in any of the tissues of pigs and chickens. 3-Methyl-2-acetyl quinoxaline (M1), 3-methyl-2-(1-hydroxyethyl) quinoxaline-N4-monoxide (M4), and 3-methyl-2-(1-hydroxyethyl) quinoxaline-1,4-dioxide (M6) were the common and major metabolites of MEQ in all three species. Additionally, 3-methyl-2-(1-hydroxyethyl) quinoxaline (M5), 3-hydroxymethyl-2-ethanol quinoxaline-1,4-dioxide (M7), and 3-methyl-2-(1-hydroxyethyl) quinoxaline-N1-monoxide (M8) were the major metabolites of MEQ in rats, pigs, and chickens, respectively. M1 was designated to be the marker residue of MEQ in pigs and chickens. These results provide scientific data for the determination of marker residues and withdrawal time of MEQ in food animals and improve the understanding of the toxicity and disposition of MEQ in animals.

Tunable growth of silver nanobelts on monolithic activated carbon with size-dependent plasmonic response.

Silver is one of the most important materials in plasmonics. Tuning the size of various silver nanostructures has been actively pursued in the last decade. However, silver nanobelt, a typical one-dimensional silver nanostructure, has not been systematically studied as to tuning its size for controllable plasmonic response. Here we show that silver nanobelts, with mean width ranging from 45 to 105 nm and thickness at ca. 13 nm, can grow abundantly on monolithic activated carbon (MAC) through a galvanic-cell reaction mechanism. The widths of silver nanobelts are positively correlated to the growth temperatures. The width/thickness ratio of the silver nanobelts can be adjusted so that their transversal plasmonic absorption peaks can nearly span the whole visible light band, which endows them with different colours. This work demonstrates the great versatility of a simple, green and conceptually novel approach in controlled synthesis of noble metal nanostructures.

Surface-Limited Synthesis of Pt Nanocluster Decorated Pd Hierarchical Structures with Enhanced Electrocatalytic Activity toward Oxygen Reduction Reaction.

Exploring superior catalysts with high catalytic activity and durability is of significant for the development of an electrochemical device involving the oxygen reduction reaction. This work describes the synthesis of Pt-on-Pd bimetallic heterogeneous nanostructures, and their high electrocatalytic activity toward the oxygen reduction reaction (ORR). Pt nanoclusters with a size of 1-2 nm were generated on Pd nanorods (NRs) through a modified Cu underpotential deposition (UPD) process free of potential control and a subsequent surface-limited redox reaction. The Pt nanocluster decorated Pd nanostructure with a ultralow Pt content of 1.5 wt % exhibited a mass activity of 105.3 mA mg(-1) (Pt-Pd) toward ORR, comparable to that of the commercial Pt/C catalyst but 4 times higher than that of carbon supported Pd NRs. More importantly, the carbon supported Pt-on-Pd catalyst displays relatively small losses of 16% in electrochemical surface area (ECSA) and 32% in mass activity after 10 000 potential sweeps, in contrast to respective losses of 46 and 64% for the commercial Pt/C catalyst counterpart. The results demonstrated that Pt decoration might be an efficient way to improve the electrocatalytic activity of Pd and in turn allow Pd to be a promising substitution for commercial Pt catalyst.

Characterization of a layered methylene blue/vanadium oxide nanocomposite and its application in a reagentless H2O2 biosensor.

Layered nanocomposite of methylene blue (MB)-intercalated vanadium oxide was obtained through a simple hydrothermal synthesis method using MB, V2O5, and NaI as starting materials. The intercalation reaction was proven to be successful using X-ray diffraction pattern. The MB-V2O5 nanocomposite was characterized using a scanning electron micrograph, infrared spectra, thermogravimetric analysis, UV spectra, and electrochemical measurements. The intercalated MB cations showed a fine diffusion-controlled electrochemical redox process and facilitated the immobilized horseradish peroxidase's (HRP) good catalytic reduction upon H2O2. The as-prepared MB-V2O5/HRP biosensor showed a linear response to H2O2 over a range from 2.0 × 10(-6) to 9.5 × 10(-5) M with a detection limit of 9.7 × 10(-7) M (S/N ratio = 3).

[Community characters of Lophatherum gracile in Yongchuan district of Chongqing].

To understand Lophatherum gracile plant community's structural characteristics, a survey of community structure and species diversity was conducted through quadrat sampling in Yongchuan district of Chongqing. The results showed that there were 386 species vascular plants, belonging to 117 families and 229 genera. Based on habitat, community structure and species composition, L. gracile were found in three community types: Pinus massoniana community, banboo community, shurb community. Vertical structure was composed of three layers, including tree layer, shrub layer and herb layer. Species in shrub layer was the richness. P. massoniana is the only dominant species of the community, it can not regenerate naturally, the shrub layer has a greater effect on the community of L. gracile in the future. In addition, the banboo community and shurb community is not stable because of human's activity. Therefore, the community characters of L. gracile should be taken care of conservation when the resources are utilized.

[History of heavy metal pollution from tidal flat in Haizhou Bay].

Coastal zone could be considered as an important sink of regional source to sink and preserve historical records of environmental evolution. Four sediment cores, collected from tidal flat at Haizhou Bay near Lianyungang City, were examined for concentrations of heavy metals including Cd, Cr, Cu, Mn, Pb and Zn in core sediments to investigate the historical input of trace metals. In addition, sediment rates of cores LH3 and LH4 were determined based on radionuclide 210Pb. The results showed that grain size control effect was not the main factor that influenced the distribution of heavy metals. Heavy metals concentrations in the surface sediments were higher than these regional background values. Furthermore, Al element as a proxy of grain size was selected for normalization and calculation of metal enrichment factor (EF) and anthropogenic heavy metal fluxes. The results revealed that heavy metals in tidal flats were continuously enriched in the past decades, meanwhile, tidal flats have been significantly subjected to contaminations due to anthropogenic activities. Moreover, the depth profiles of heavy metals fluxes correspond to scenario of social-economy development of Lianyungang, which is an important urban area near Haizhou Bay. From 1950s to 2005, anthropogenic fluxes of metals increased with fluctuations, whereas, since 2005 anthropogenic fluxes declined, which may be correlated to the adjustment of industrial structure as well as the strengthened environmental regulation.

Green "planting" nanostructured single crystal silver.

Design and fabrication of noble metal nanocrystals have attracted much attention due to their wide applications in catalysis, optical detection and biomedicine. However, it still remains a challenge to scale-up the production in a high-quality, low-cost and eco-friendly way. Here we show that single crystalline silver nanobelts grow abundantly on the surface of biomass-derived monolithic activated carbon (MAC), using [Ag(NH3)2]NO3 aqueous solution only. By varying the [Ag(NH3)2]NO3 concentration, silver nanoplates or nanoflowers can also be selectively obtained. The silver growth was illustrated using a galvanic-cell mechanism. The lowering of cell potential via using [Ag(NH3)2]⁺ precursor, together with the AgCl crystalline seed initiation, and the releasing of OH⁻ in the reaction process, create a stable environment for the self-compensatory growth of silver nanocrystals. Our work revealed the great versatility of a new type of template-directed galvanic-cell reaction for the controlled growth of noble metal nanocrystals.

[Establishment of seedling classification criteria of Coptis chinensis by dynamic clustering method].

OBJECTIVE: To establish seedling classification criteria of Coptis chinensis. METHOD: The height of plant, leaf number, leaf length, leaf wide, weight of leaf, weight of root were measured, the main measurement indexes of seedlings of C. chinensis were chosen through correlation and regression analysis. The seedling classification criteria were formulated by dynamic clustering analysis. RESULT: The criteria of the 1st-grade seedlings were as follows: leaf number above 8 leaves, height of plant between 12 and 14 cm. The criteria of the 2nd-grade seedlings were as follows: leaf number between 6 and 8 cm, height of plant between 9 and 12 cm. The criteria of the 3rd-grade seedlings were as follows: leaf number between 4 and 6 cm, height of plant above 9 cm. CONCLUSION: The seedling classification criteria of C. chinensis was scientific and feasible, and can be used for the quality control standard of C. chinensis.

Bis(1H-benzimidazole-κN(3))bis-[2-(naphthalen-1-yl)acetato-κ(2)O,O']nickel(II) monohydrate.

In the title compound, [Ni(C(12)H(9)O(2))(2)(C(7)H(6)N(2))(2)]·H(2)O, The Ni(II) cation is located on a twofold rotation axis and is six-coordinated in a distorted NiN(2)O(4) octa-hedral geometry. The asymmetric unit consists of a nickel(II) ion, one 2-(naphthalen-1-yl)acetate anion, a neutral benzotriazole ligand and one half of a lattice water mol-ecule. The crystal packing is stabilized by O-H⋯O and N-H⋯O hydrogen bonds. The title compound is isotypic with its Cd(II) analogue.

Pyrrolidin-1-ium 2-(naphthalen-1-yl)acetate-2-(naphthalen-1-yl)acetic acid (1/1).

In the title compound, C(4)H(10)N(+)·C(12)H(9)O(2) (-)·C(12)H(10)O(2), the pyrrolidine ring adopts an envelope conformation and the dihedral angle between the planes of the two naphthalene ring systems is 8.34 (10)°. The crystal structure is stabilized by O-H⋯O and N-H⋯O hydrogen bonds.

Diaqua-bis-(1-methyl-1H-imidazole-κN(3))bis-[2-(naphthalen-1-yl)acetato-κO]cobalt(II).

In the title compound, [Co(C(12)H(9)O(2))(2)(C(4)H(6)N(2))(2)(H(2)O)(2)], the Co(II) ion is located on an inversion centre and displays a distorted octa-hedral coordination geometry. Two O atoms from two water mol-ecules and two carboxyl-ate O atoms from two 2-(naphthalen-1-yl)acetate ligands are in the equatorial plane and two N atoms from two 1-methyl-1H-imidazole ligands are in the axial positions. The structure is stabilized by intra-molecular O-H⋯O hydrogen bonds. Inter-molecular O-H⋯O hydrogen bonds link the complex mol-ecules into chains along [100].

Bis(1H-benzimidazole-κN)bis-[2-(naphthalen-1-yl)acetato-κO,O']manganese(II) monohydrate.

In the title compound, [Mn(C(12)H(9)O(2))(2)(C(7)H(6)N(2))(2)]·H(2)O, the Mn(II) ion is located on a twofold rotation axis and six-coordinated, displaying a distorted MnN(2)O(4) octa-hedral geometry. The crystal packing is stabilized by N-H⋯O hydrogen bonds, which give rise to a one-dimensional structure along [001], and π-π inter-actions between the imidazole rings and between the benzene rings of the 2-(naphthalen-1-yl)acetate ligands [centroid-centroid distances = 3.761 (3) and 3.728 (4) Å]. The contribution of the electron density associated with the disordered water molecules was not considerd in the final structure model.

Tetra-kis(µ-naphthalene-1-acetato-κO:O')bis-[(N,N-dimethyl-formamide-κO)copper(II)].

The asymmetric unit of the title compound, [Cu(2)(C(12)H(9)O(2))(4)(C(3)H(7)NO)(2)], contains two independent centrosymmetric dinuclear copper(II) complexes. The central paddle-wheel units are formed by four bridging bidentate naphthalene-1-acetate ligands with two dimethyl-formamide ligands in the axial positions. The unique Cu(II) ions have slightly distorted square-pyramidal coordination geometries. One of the naphthalene rings is disordered over two sets of sites, with refined occpancies of 0.535 (4) and 0.465 (4).

Bis-(2-methyl-1H-imidazole-κN)bis[2-(naphthalen-2-yl)acetato-κO]copper(II).

In the crystal structure of the title compound, [Cu(C(12)H(9)O(2))(2)(C(4)H(6)N(2))(2)], the Cu(II) cations are square-planar coordinated by two 1-naphthyl-acetate anions and two 2-methyl-imidazole ligands into discrete complexes that are located on centres of inversion. These complexes are linked into chains parallel to [010] by inter-molecular N-H⋯O hydrogen bonding between the N-H H atom of the 2-methyl-imidazole ligands and the carboxyl-ate O atoms that are not involved in metal coordination.

Bis(1-methyl-1H-imidazole-κN)bis-[2-(naphthalen-1-yl)acetato-κO]copper(II) monohydrate.

In the crystal structure of the title compound, [Cu(C(12)H(9)O(2))(2)(C(4)H(6)N(2))(2)]·H(2)O, the Cu(II) atom is coordinated by two 2-(naphthalen-1-yl)acetate anions and two 1-methyl-imidazole ligands, giving monomeric complexes with a square-planar coordination environment. Two complex mol-ecules and two water mol-ecules form a centrosymmetric ring system via O-H⋯O hydrogen bonds.

[Dynamic accumulation of effective components and biomass of Coptis chinensis in Hongya county].

OBJECTIVE: To study the dynamic accumulation of the effective components and biomass of Coptis chinensis, so to provide the experimental date of optimal harvest time for C. chinensis in Hongya county. METHOD: The samples of three to five years were gathered from the same field and time. The biomass was analyzed by weighed. The jatrorrhizine, columbamine, epiberberine, coptisine, palmatine and berberine in C. chinensis were analyzed by HPLC. RESULT: With the increasing of years of growth, the rootstalk biomass of C. chinensis was increasing continuously. The biomass growth of four-year-old C. chinensis was the fastest in the year. From September to October was the fastest season of the growth of rootstalk. The dynamic accumulation in rootstalk C. chinensis had regularity in the certain extend. The contents of six alkaloids and all alkaloids in 4-year-old C. chinensis were more than that in 3-years-old and 5-year-old. The contents of six alkaloids were mostly highest in August. From July to December, there is no significant difference in the contents of columbamine, epiberberine, coptisine, palmatine, berberine and all alkaloids in 4-years-old C. chinensis. CONCLUSION: According to the biomass and the accumulation pattern of the effective components in the C. chinensis, the optimal harvest time is from September to October of 4-year-old C. chinensis.