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Three new 3,4-seco-grayanane diterpenoids, neopierisoids D-F (2-4), and a new natural one, neopierisoid C (1), were isolated from the flowers of Pieris japonica. Their structures were elucidated on the basis of extensive spectroscopic analysis, including one and two dimensional (1- and 2D)-NMR, as well as high resolution-electron ionization (HR-EI)-MS.

The first nickel-catalyzed, magnesium-mediated reductive cross-coupling between benzyl chlorides and aryl chlorides or fluorides is reported. A variety of diarylmethanes can be prepared in good to excellent yields in a one-pot manner using easy-to-access mixed PPh3/NHC Ni(II) complexes of Ni(PPh3)(NHC)Br2 (NHC = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene, IPr, 1a; 1,3-di-tert-butylimidazol-2-ylidene, ItBu, 1b) as catalyst precursors. Activation of polychloroarenes or chemoselective cross-coupling based on the difference in catalytic activity between 1a and 1b is used to construct oligo-diarylmethane motifs.

An efficient one-pot intermolecular reductive cross-coupling of unactivated primary and secondary alkyl chlorides bearing β-hydrogens with aryl bromides is described. A combination of magnesium turnings and a catalytic amount of the commercially available iron(III) complex Fe(PPh3)2Cl3 was used, and the conditions were also successfully extended to an intramolecular reaction for the first time. Both types of cross-coupling reactions proceed under mild conditions, involving the in situ generation of aryl Grignard reagents, and show good applicability to a variety of readily available unactivated alkyl chlorides, which have previously been challenging substrates in iron-catalyzed reductive cross-coupling reactions.

isolation and structure elucidation of new prepylflavonol glycosides such as epimedkoreside A (I)

An efficient protocol is developed for the ligand-free and heterogeneous Pd-C-catalyzed one-pot, three-component synthesis of aryl-substituted benzimidazoles from benzyl alcohols by using water as the solvent.

Four new iridoids, incarvoids D-F, (I)-(III), incarvoid B 9-O-β-D-glucopyranoside (V), and one new monoterpenoid, argutoid B (V) are isolated together with 14 known compounds.

The one-pot title reaction starts from aryl substituted Baylis-Hillman phosphonium salts, arylglyoxylates, alkyl cyanides, and primary alkyl amines and does not tolerate aryl amines.

Chloranthus, a genus of the family Chloranthaceae, which is mainly distributed in eastern and southern Asia, has been used in Chinese folk medicine due to its antitumor, antifungal, and anti-inflammatory activities. This review compiles the research on isolation, structure elucidation, structural diversity, and bioactivities of Chloranthus secondary metabolites reported between 2007 and 2013. The metabolites listed encompass 82 sesquiterpenoids, 50 dimeric sesquiterpenoids, 15 diterpenoids, one coumarin, and five other compounds. Among them, dimeric sesquiterpenoids, the characteristic components of plants from the genus Chloranthus, have attracted considerable attention due to their complex structures and significant biological features, e.g., antitumor, antibacterial, antifungal, anti-inflammatory, and hepatoprotective activities, and potent and selective inhibition of the delayed rectifier (IK) K(+) current and tyrosinase.

Phytochemical investigation on the rhizomes of Sinomenium acutum led to the isolation of new alkaloids sinomacutines A E (1-5), and cephalonine-2-O-beta-n-glucopyranoside (6), along with known tetrahydroisoquinoline alkaloids (7-9). Among them, sinomacutines A C were new bistetrahydroisoquinoline alkaloids with morphinane-proaporphine and morphinane-benzyltetrahydroisoquinoline types, and coupled with unique C-CH2-N unit. Their structures with absolute configuration were elucidated on the basis of 1D and 2D NMR, and ECD spectra analysis. The new compounds were evaluated for their anti-inflammatory and cytotoxic activities, and sallisonine B (2) showed moderate ability to inhibit NO production of LPS-stimulated RAW264.7 macrophages, as well as sallisonine A (1) showed weak inhibitory effects against five cancer cell lines. (C) 2014 Elsevier Ltd. All rights reserved.

Alcohols are of great importance as cheap and readily available organic materials for the preparation of many pharmaceutical products and fine chemicals. In addition, alcohols as electrophiles instead of alkyl halides in C-C (N) bonds forming reactions are particularly attractive because the process produces only water as byproduct. In spite of the existence of many synthetic routes, there are limited reports involving biarylmethanols. The palladium-catalyzed Suzuki reaction is an extremely efficient method for the construction of biaryl compounds. Among various Pd catalysts, palladacycles are one of the most active catalysts for the coupling reactions. From the economical and environmental points of view, employing readily accessible aryl chlorides and the use of water as a solvent in this reaction offer many advantages. However, there have been a few reports which demonstrated that palladacycles catalyzed Suzuki reaction of limited aryl chlorides in water. To our knowledge, only two accounts has been reported concerning the Suzuki of 4-chlorophenylmethanol in organic solvent. Recently, we have developed a cationic cyclopalladated ferrocenylpyrimidine catalyzed Suzuki reaction of aryl halides and 4-(hydroxymethyl)phenylboronic acid for the synthesis of substituted biarylmethanols in water. However, substrates are limited to the aryl bromides and activated aryl chlorides. To date, there is no report that investigates the Suzuki reaction of chlorophenylmethanol in water. As a continuation of our interest in the synthesis of biarylmethanols, we have prepared a new phosphine adduct of palladacycle 2 from the reaction of cyclopalladated ferrocenyloxime dimer 1 with commercially available 2-dicyclohexylphosphanyl-2'-(N,Ndimethylamino) biphenyl (DCPAB) (Scheme 1) and developed a practical method for the synthesis of biarylmethanols by the Suzuki reaction of chlorophenylmethanol and arylboronic acids in water. Complex 2 is airand moisture-stable, both in solid state and in solution. It was fully characterized by elemental analysis, IR, NMR and ESI-MS. In comparison with the corresponding frequencies of the free ferrocenyloxime, the C=N absorptions of 2 has been shifted to low values (1599 cm), indicating that the N atom is coordinated to palladium. The H NMR spectrum of 2 exhibits more signals than expected, and the P NMR appears two singlets at δ 65.54 and 67.15 ppm, suggesting the existence of isomers in solution. A similar phenomenon was also found in the H NMR

The multicomponent reaction of aminobenzyl alcohols, acetophenones, and arylboronic acids provides access to a variety of 2,6-diarylquinolines as versatile ligands of photoactive complexes.

β-Lactam scaffold was fabricated regioselectively by a facile one-pot base-mediated synthesis. The reactions of bromoacetic acid 1, primary amines 2, isocyanides 3, and arylglyoxals 4 produced 2-aroyl-4-oxoazetidine-2-carboxamides 6 in good yields via a one-pot tandem Ugi condensation and intramolecular C-alkylation at room temperature in the presence of Cs2CO3.

A metal-free [3 + 2 + 1]/[2 + 2 + 1] biscyclization strategy has been developed for the stereospecific construction with concomitant derivation of biologically significant indolizin-5(1H)-ones from simple and commercial starting materials. The transformations are notable because they can yield five new σ bonds and six stereocenters including a quaternary carbon center in a single operation.

The new phosphorSm(IO3)3·2H2O is prepared under mild hydrothermal conditions from the yellow solid product of a heated mixture of Sm2O5 and conc.

[BupyH]·[B5O6(OH)4] is prepared under solvothermal conditions from H3BO3, N-butyl-pyridinium (Bupy) bromide, Al(O-iPr)3, H2O, and pyridine, (autoclave, 180 °C, 7 d).

Ionic Fe(III)-complexes based on novel bis(phenol)-functionalized benzimidazolium cation are synthesized and applied to the cross-coupling of Grignard reagents (I) with primary and secondary alkyl halides (II) bearing β-hydrogens.

The microwave-assisted synthesis and the biological evaluation of a series of the title compounds is described.

A one-pot base-mediated synthesis of 5-oxopyrrolidine-2-carboxamides was developed. The reaction of Baylis–Hillman bromides 1, primary amines 2, isocyanides 3 and arylglyoxals 4 produced the 5-oxopyrrolidine-2-carboxamides 6 in good yields via a tandem Ugi condensation and intramolecular substitution at room temperature in the presence of Cs2CO3.

A novel multicomponent strategy for the efficient synthesis of tricyclic pyrrolo[1,2-a]quinolines has been described. The bond-forming efficiency, accessibility and generality of this synthesis make it highly attractive to assemble tri-heterocyclic scaffolds.

Sodium benzoate is shown to be an efficient catalyst for the Knoevenagel condensation of aromatic aldehydes and active methylene compounds.

Many species of the family Ericaceae, such as the plants belonging to the genera Pieris, Rhododendron, Lyonia, Kalmia, and Leucothoe, are usually rich in grayanane-type diterpenoids with a 5/7/6/5 ring system, which is responsible for the toxicity of these species [1, 2]. Recently, a series of novel highly acylated diterpenoids with specific 3,4-secograyanane skeleton have been reported from Rhododendron molle and Pieris formosa by Jian-Gong Shi and coworkers, Sheng-HongLi and coworkers and our group [3 – 6]. In searching for new natural compounds with more new skeletons, we had investigated the leaves and stems of Lyonia ovalifolia, and obtained a novel polyesterified diterpenoid with a unique 9,10-seco grayanane skeleton, named lyonin A [7]. This finding made us interested in the biosynthetic pathway of seco-grayanane diterpenoids, and we further investigated the chemical constituents, especially diterpenoids, of the fruits of

An efficient method for the synthesis of acylals from different aldehydes and acetic anhydride in the presence of magnesium methanesulfonate–acetic acid under ultrasound irradiation at room temperature is achieved. Only 1.5 mol% of magnesium methanesulfonate and a small quantity of acetic acid are needed to effect the reaction. Selective conversion of aldehydes is observed in the presence of ketones. The catalyst remains active and exhibits no substantial loss of activity or selectivity in up to three reaction cycles.

The protocol is applied to various substituted indoles and can be extended to pyrrole and acetylacetone.

In this paper, the research on the catalyst sulfur poisoning in recent years were reviewed, including the reason and mechanism of sulfur poisoning, dynamics for deactivation, recovery and regeneration of catalyst.

Phytochemical investigation on the fruits of Pieris formosa resulted in the isolation of three new highly acylated 3,4-seco-grayanane diterpenoids, pierisformotoxins E-G (1-3). Their structures were elucidated on the basis of extensive spectroscopic analysis, including 1D-, 2D-NMR, electrospray ionization-mass spectra (ESI-MS) and high resolution (HR)-MS.

Two fundamental chemical element properties, melting point and pseudopotential radii, were found to be strongly correlated not only to the effects of additives in galvanizing but also to the crystal structures of their correspondent binary zinc compounds, based on experimental data from the literature. It was suggested that both the bulk properties (such as galvanizing effects in this study) and crystal structures might be regulated by the same set of constituent chemical element properties. Although most chemical elements, as well as crystal structures of binary compounds, are well investigated and understood, our knowledge of bulk properties of known systems is still less comprehensive. In this study, a correlation between effects of additives in galvanizing, through the behaviors of their correspondent zinc compounds, and two selected chemical element properties was first established, based on available literature data. The selected two element properties were, then, used to correlate to the crystal st...

A new Ni12 cluster based on polyoxometalate ligands [Ni12(OH)9-WO4(W7O26(OH))(PW9O34)3]25- (1) has been assembled in aqueous solution containing [PW9O34]9-, WO42-, and NiCl2 3 6H2O. The Ni12 core in 1 shows a unique three-petal flower-shaped structure composed of three Ni4 cubane units. Magnetic investigation indicates the presence of dominantly ferromagnetic interactions within the Ni12 core.

A novel red emitting phosphor, Sm 3+ doped Mg 2 GeO 4 was prepared by the traditional solid state reaction. The luminescence properties were investigated in details. Diffuse reflection spectra of undoped and Sm 3+ doped Mg 2 GeO 4 were measured. The excitation spectra present a broad band and are consistent with the diffuse reflectance spectra. The emission bands which peak at 631 and 659 nm are due to the 4 G 5/2 – 6 H 9/2 transition. The CIE coordinates of the phosphor Mg 2 GeO 4 :Sm 3+ is x = 0.626 and y = 0.323 which are close to the NTSC standard values for red. The dependence of the emission intensity on the Sm 3+ dopant concentration was studied: the optimum doping levels for Sm 3+ is x = 0.03 molar ratio. The luminescence properties suggest it is a good novel red emitting phosphor.