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Artaboterpenoids A and B (1 and 2), two novel bisabolene-derived sesquiterpenoids, were isolated from the roots of Artabotrys hexapetalus. Their structures with absolute configurations were elucidated by spectroscopic methods, and electronic circular dichroism (ECD) analyses. Notably, 1 featured a novel carbon skeleton with a new C-2-C-10 linkage, and 2a and 2b, a pair of enantiomers, represented the first examples of 1,2-seco-bisabolene-type sesquiterpene lactones. 2a exhibited cytotoxic effects against HCT-116, HepG2, A2780, NCI-H1650, and BGC-823 cell lines with IC50 values of 1.38-8.19 μM. Plausible biogenetic pathways for artaboterpenoids A and B were proposed.

The mechanism-oriented reaction design for the divergent synthesis of chiral molecules from simple starting materials is highly desirable. In this work, aromatic amide-derived nonbiarylatropisomer/silver (silver/Xing-Phos) complex was used to catalyze the Michael addition of glycine aldimino esters to chalcones and successfully applied to the subsequent cyclocondensation to afford substituted cis-Δ(1)-pyrroline derivatives with up to 98 % ee. Besides the inherent performance of the chiral Ag/Xing-Phos catalyst system, it was found that the workup of such reactions played an important role for the stereoselective construction of stereodivergent Δ(1)-pyrrolines, in which an epimerization of the cis-Δ(1)-pyrrolines to the trans-isomers during was revealed.

A new method was developed to synthesize N2-alkyl-substituted 1,2,3-triazole through N-iodosuccinimide (NIS) mediated iodofuctionalization reaction of the alkene group with bi-, mono-, and unsubstituted NH-1,2,3-triazoles. The favored N-1 type hydrogen bond between the iodonium ion intermediate and 1,2,3-triazole was supposed to be generated, which gave the desired N2-alkyl triazole with a high N2-selectivity.

The copper-catalyzed enantioselective conjugate addition of diethylzinc to acyclic enones was achieved with chiral sulfoxide–phosphine (SOP) ligands. This process showed good functional group tolerance and gave the 1, 4-adducts with excellent enantioselectivities (up to 96% ee).

An aryne-induced dearomatized phosphonylation reaction has been developed. Electron-deficient azaarenes such as quinolines, isoquinolines, phenanthroline and acridine undergo multicomponent reaction with arynes and dialkylphosphites to afford the corresponding dearomatized phosphonylated heterocycles in 50–90% yields.

Nine new and five known corynanthe alkaloids are isolated as exemplified by the structures shown in the scheme.

A copper-catalyzed and microwave-assisted synthesis of fully substituted pyrroles has been developed. A series of pentasubstituted pyrroles, especially α-arylpyrroles, could be obtained in moderate to good yields (up to 93%) through a tandem propargylation/alkyne azacyclization/isomerization sequence from readily available β-enamino compounds and propargyl acetates.

New cytochalasans, periconiasin G (I) and periconiasin H (II) are isolated from Periconia sp.

As a newly developed fluorescent probe, DNA functionalized quantum dots (QDs) with unique optical properties play a critical role in the bioanalytical applications. The present review provides an overview on the conjugation technologies of DNA to QDs, including electrostatic attraction, covalent attachment, specific effect and direct synthesis. In addition, we summarize recent advances on DNA functionalized QDs in the bioapplications, such as targeting nucleic acids, ions, small molecules and the protein detection, cell imaging and disease diagnosis. Finally, we envision aspects concerning current challenges on the DNA functionalized fluorescent QDs.

A palladium-catalyzed ortho -C–H-acylation of 2-arylpyridine using phenylacetylenes and styrene epoxide as the acylated reagents was developed. With the employment of tert -butyl hydroperoxide (TBHP) as the oxidant and a phosphorous ligand, the protocol generates corresponding aryl ketones in moderated to good yields with high regioselectivity and good functional group compatibility.

A novel copper-catalyzed microwave-promoted propargyl­ation/alkyne oxacyclization/isomerization cascade for the synthesis of 2-methylfuro[3,2-c]coumarins has been developed. This reaction provides furo[3,2-c]coumarins in moderate to good yields (≤82%) from readily available 4-hydroxycoumarins and terminal propargyl acetates as starting materials. Interestingly, by changing the solvent from dimethyl sulfoxide to 1,2-dichloroethane, the isomeric series of 2-meth­ylene-2,3-dihydrofuro[3,2-c]coumarins were obtained in good to acceptable yields (≤85%).

Eight new grayanane-type diterpenoids, pieristoxin L-S (1–8), and seven known diterpenoids, grayanoside D (9), rhodomolin I (10), pieristoxin H (11), grayanotoxin II (12), pierisformoside B (13), grayanoside C (14) and bis-deacetylkalmitoxin-VI (15), were isolated from the twigs of Pieris formosa. The structures of these compounds were elucidated using extensive spectroscopic analyses, including electronic circular dichroism (ECD). Pieristoxin L (1) is the first example of a 1,7-epoxy-grayanane-type diterpenoid. The analgesic activities of compounds 2–6, 8, and 10–15 were evaluated using an acetic acid-induced writhing test in mice. Compounds 3–6, 8, 10, 12, and 15 exhibited significant analgesic activity at 5 mg/kg (ip) compared to vehicle-injected mice (P

A Pd-catalyzed highly enantioselective three-component coupling of 1,3-dienes with aryl iodines and sodium dialkyl malonates has been successfully established by using a H8-BINOL-based phosphoramidite ligand. This reaction proceeded via a Pd-catalyzed cascade arylation and asymmetric allylic alkylation reaction, providing an efficient strategy for the enantioselective 1,2-difunctionalization of 1,3-dienes.

o-Hydroxy aromatic aldimines are treated with alkynyl aldehydes under conditions A) to produce the desired heterocyclic scaffold as important structural motif in bioactive compounds.

A palladium-catalyzed ortho-C–H-benzoxylation of 2-arylpyridines using iodobenzene dibenzoates has been developed. The reaction employed the stable and easily accessible hypervalent iodine reagents as both benzoxylate source and oxidant which made the protocol simple and facile. It showed high regioselectivity and good functional group tolerance, and gave the mono-benzoxylation products in moderate to excellent yields.

Four new compounds, pericoannosin A (I) having an unusual carbon skeleton and periconiasins D-F (II), (III), and (IV) are isolated.

Merrilliaquinone, a new racemic quinone has been isolated from Illicium merrillianum, chiral separated, and spectroscopic analyzed.

Pestalotriols A (1) and B (2), two new metabolites featuring a unique spiro[2.5]octane skeleton, were isolated from an endophytic fungus Pestalotiopsis fici. Their structures were elucidated primarily by NMR experiments, and the absolute configurations of 1 and 2 were assigned by electronic circular dichroism calculations.

Six new alkaloid glycosides, clausenasides A-F, and two novel quinoline alkaloids, clausenasides G-H, are isolated along with ten known compounds from the stems of C.

Chemical analysis of a marine-derived fungus, Chaunopycnis sp. (CMB-MF028), isolated from the inner tissue of a pulmonate false limpet Siphonaria sp., collected from rock surfaces in the intertidal zone of Moora Park, Shorncliffe, Queensland, yielded the tetramic acid F-14329 (1) and new analogues, chaunolidines A-C (2-4), together with the new pyridinone chaunolidone A (5), and pyridoxatin (6). Structures inclusive of absolute configurations were assigned to 1-6 on the basis of detailed spectroscopic analysis, X-ray crystallography, electronic circular dichroism (ECD), biosynthetic considerations and chemical interconversion. Chaunolidine C (4) exhibits modest Gram-positive antibacterial activity (IC50 5-10 μM), while chaunolidone A (5) is a selective and potent inhibitor (IC50 0.09 μM) of human non-small cell lung carcinoma cells (NCI-H460). Tetramic acids 1-4 form metal chelates with Fe(III), Al(III), Cu(II), Mg(II) and Zn(II).

The focus on this mini-review is on the use of metalloligands for the construction of discrete self-assembled, polyhedral metallo-cages. This metalloligand approach employs metal bound multifunctional ligand building blocks that display predetermined, well-defined electronic and structural preferences that facilitate the rational design and construction of both homo- and heteronuclear cages. The assembled cages exhibit a variety of defined topologies that, for example, range from trigonal bipyramidal to rhombododecahedral.

Coordination polymers (CPs) can be formed by the self-assembly of metal ions and one kind of ligand or mixed ligands. Carboxylate anions have been extensively utilized to construct metal–organic CPs with diverse structures and topologies as well as versatile properties. The introduction of neutral nitrogen-donor co-ligands in such metal carboxylate system is an effective strategy for tuning the architectures and functionalities of metal–organic CPs. As a family of neutral nitrogen-donor co-ligands, amide-bridged polypyridine compounds have been introduced into such metal carboxylate system in the past decade. A large number of metal–organic CPs derived from the mixed ligands of carboxylate and amide-bridged polypyridine have been reported. Therefore, we present the recent developments of transition metal carboxylate CPs with amide-bridged polypyridine co-ligands in this highlight. We summarize their syntheses, structures, architectural influence factors and properties in detail. Such highlight may play a significant role in the rational design and construction of amide-bridged polypyridine-based transition metal carboxylate CPs with structure-dependent properties.

Tripterlides A–F (1–6), six new abietane diterpenoid derivatives, together with six known abietane diterpenoids (7–12) were obtained from the leaves of Tripterygium wilfordii. Tripterlides A–C (1–3) were novel 14(13 → 12),18(4 → 3)-diabeo-abietanoids possessing a 6/6/5 tricyclic ring system. These unusual structures, including their absolute configurations, were determined from UV, IR, HRESIMS, 1D and 2D-NMR data and through comparisons of their experimental and calculated electronic circular dichroism (ECD) spectra. A plausible biosynthetic pathway for 1–3 was proposed. Furthermore, in an in vitro bioassay, 5, 6, 8, and 10–12 showed significant cytotoxic effects against five human cell lines, and 6, 8, 10–12 also exhibited moderate inhibitory activities on hypoxia-inducible factor 1 (HIF-1), which is relevant to tumor development.

A simple and efficient methylthiolation protocol was successfully established for the synthesis of ketone-substituted indoles bearing 3-methylthioether moiety. The new synthetic approach featured metal-free oxidation and methylthiolation of alcohol-containing indoles, in which new C–S bond and CO bond were formed simultaneously using dimethyl sulfoxide as the sulfur source under the Swern oxidation conditions. The methylthiolation reaction provides a simple and facile procedure to methylthiolated indoles from readily available starting materials in good yields.

A wide range of 2-tetralyl carboxylic esters are synthesized by Pd-catalyzed tandem carboxylation and direct intramolecular coupling using Selectfluor as oxidant under mild reaction conditions.

The operationally simple and efficient procedure has a broad substrate scope and proceeds diastereoselectively.

The heterodimers, denticulatains A (I) and B (II), possessing an unprecedented stilbene-diterpene-type skeleton are isolated from the fronds of Macaranga denticulata.

Ganoboninones A-F (I)-(IV) possessing an interesting tetradecahydrobenzo[4,5]indeno[1,7a-c]furan backbone are isolated along with three known compounds, ganoboninketals A-C, from the fruiting bodies of the medicinal mushroom Ganoderma boninense.

A breakthrough in asymmetric Friedel-Crafts reactions is achieved by using terminal 1,1-diarylalkenes as alkylating reagents, which avoids the generation of side products.

Developing highly efficient catalysts for the oxygen reduction reaction (ORR) is key to the fabrication of commercially viable fuel cell devices and metal–air batteries for future energy applications. Herein, we review the most recent advances in the development of Pt-based and Pt-free materials in the field of fuel cell ORR catalysis. This review covers catalyst material selection, design, synthesis, and characterization, as well as the theoretical understanding of the catalysis process and mechanisms. The integration of these catalysts into fuel cell operations and the resulting performance/durability are also discussed. Finally, we provide insights into the remaining challenges and directions for future perspectives and research.

Both electron-rich and electron-deficient substrates can be used and various functional groups are tolerated.

Pure carbon nanodots prepared from mixtures of multi-wall carbon nanotubes oxide and water (ultrasonication for 8 h) followed by hydrothermal treatment (autoclave, 180 °C, 8 h) drive photocatalytic hydrogen generation by water splitting without any modification and cocatalyst.

A copper catalyst system derived from TaoPhos and CuF2 was used successfully for catalytic asymmetric Huisgen [3+2] cycloaddition of azides and alkynes to give optically pure products containing succinimide- and triazole-substituted quaternary carbon stereogenic centers. The desired products were obtained in good yields (60-80 %) and 85:15 to >99:1 enantiomeric ratio (e.r.) in this click cycloaddition reaction.

The one-pot iron-catalyzed cycloaddition of indole and o-phthalaldehyde afforded indolyl benzo[b]carbazoles via sequential carbon–carbon bond-forming addition, cyclization involving intramolecular alkylation and aromatization forming a benzene ring. In addition, the fluorescence properties of such indolyl benzo[b]carbazoles were investigated, in which significant changes in fluorescent intensity were observed upon the addition of trimethylchlorosilane (TMSCl) or trifluoroacetic acid (TFA).

We describe a direct synthesis of various ynones from readily available aldehydes and hypervalent alkynyl iodides. In this method, a gold catalyst and a secondary amine work synergistically to produce the trisubstituted allenyl aldehyde, which can be converted to the desired ynone through an in situ C–C bond oxidative cleavage using molecular oxygen.

The title reaction has a wide substrate scope and proceeds with high (E)-stereospecificity.

Primary alkyl alcohols (I) are directly converted into acetals (II), with no need of any externally added reagents, including hydrogen acceptors.

A practical and efficient procedure for the selective synthesis of β-hydroxy esters (III) via a silyl-Reformatsky reaction catalyzed by a Cu(II)-salan complex is developed.

Polyoxometalates (POMs) have attracted a lot of interest due to their novel structure characteristics and various connection modes. POM-based coordination polymers with entangled structures, an indispensable branch of entangled networks, take advantage of the features of POMs, and have received increasing attention. Much effort has been devoted over the past few decades toward their preparation and the analysis of their unusual entangled topology. In this review, we will summarize a number of examples of POM-based coordination polymer that have been described according to their different entangled characteristics. Different concepts, such as interpenetration, polycatenation, polyrotaxane, poly pseudo -rotaxane and self-penetration, are employed to describe the various types of POM-based coordination polymers with entangled structures. In addition, we further classify POM-based coordination polymers with entangled structures based on the dimensionalities of the individual motifs and the roles of the POMs. Combining the advantages of the attractive potential applications of the POMs and structure diversities of the entangled frameworks, the investigation of POM-based coordination polymers with entangled structures will be a sustainable research field in coordination chemistry.

The title compound shows good antioxidant activity and is able to scavenge the diphenyl picrylhydrazyl radical with an EC50 of 20.6 μg/ml.

It was found that the cinchona-derived primary amines and their combined catalyst systems with chiral organic acid or Lewis acid have been successfully applied in the cross-aldol reaction of trifluoromethyl ketones and aliphatic ketones. Excellent yields and good enantioselectivities (up to 89% ee) of the resulting β-trifluoromethyl-β-hydroxy ketones were obtained in the chiral primary amine catalyzed cross-aldol reaction under different conditions, which also led to both enantiomers of the desired products. This study also demonstrated the importance of synergistic effect of chiral organic acid on the primary amine catalysis.

An efficient multicomponent reaction of 3-indolyl-3-oxopropanenitriles with dialkyl acetylenedicarboxylates and isocyanides under mild conditions leading to highly functionalized 6-(indol-3-yl)-4H-pyrans in moderate to good yields has been developed.

The successful construction of [6,5,6]-carbocyclic compounds is established via one-pot reaction of (E)-(ethynylphenyl)butenones with maleimide sequentially catalyzed by cinchona alkaloid-based primary amine CIN and a gold complex.

Various differently substituted tryptophan derivatives are prepared with up to 98% enantiomeric excess.

Review: classification, synthesis strategies, and applications, especially in the field of catalysis; 125 refs.

SrB6O10:xEu (x = 0.02, 0.04, 0.06, 0.08, 0.10) and SrB6O10:xEu,yMn (y = 0.02, 0.04, 0.06) phosphors are synthesized by solid state reactions of SrCO3, Eu2O3, MnO, and an excess of H3BO3 (alumina crucibles, 400 °C for 3 h and 800 °C for 5 h).