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The construction of cyano-substituted all-carbon quaternary centers via Brønsted acid-catalyzed direct C6 functionalization of 2,3-disubstituted indoles with 2,2-diarylacetonitriles is reported.

Monochamus alternatus is a longicorn beetle, an important stem borer of pine trees in China. In this study, we determined the first accurate genomic survey of M. alternatus by the next-generation sequencing (NGS), which is a relatively new methodology that can ensure the identification of large numbers of simple sequences repeat (SSR) markers, in order to increases the abundance of the Cerambycidae genome information and assist in phylogenetic, molecular systematics and evolutionary studies for Coleoptera. The result showed that the genome size was 871.09 Mb, the GC content of the genome was within normal limits (34.45%), the proportion of repetitive sequences was high (59.40%), and the heterozygosity rate was low (1.04%). The heterozygosity of M. alternatus is higher than 0.5% and the repeat rate is more than 50%. Based on this we inferred the use of Illumina+PacBio in sequencing assembly strategy is highly recommended.

Lithium-sulfur (Li-S) batteries have recently become a research hotspot because of their tempting theoretical capacity and energy density. Nevertheless, the notorious shuttle of polysulfides hinders the advancement of Li-S batteries. Herein, a two-dimensional covalent organic framework (COF) with extended π-conjugated units has been designed, synthesized, and used as sulfur recipients with 88.4 wt % in loading. The COF offers an elaborate platform for sufficient Li-S redox reactions with almost theoretical capacity release (1617 mA h g-1 at 0.1 C), satisfactory rate capability, and intensively traps polysulfides for a decent Coulombic efficiency (ca. 98.0%) and extremely low capacity decay (0.077% per cycle after 528 cycles at 0.5 C). The structural factors of the COF on the high-performance batteries are revealed by density functional theory calculations to be the high degrees of conjugation and proper interlayer space. This work not only demonstrates the great potential of COFs as highly efficient sulfur recipients but also provides a viable guidance for further design of COF materials to tackle shuttling issues toward active materials in electrochemical energy storage.

The principle of reticular chemistry has been widely used to guide the design of crystalline porous materials such as metal organic frameworks (MOFs) and covalent organic frameworks (COFs). While in the early strategies only the symmetries of the building blocks were considered for reticular synthesis of COFs, recently a few researches on COFs with hierarchical porosities indicate that connecting sequence of building blocks also plays a crucial role in determining crystalline structures of COFs. However, this important phenomenon has not been systematically investigated yet. In this article, a model system has been established to demonstrate how different connecting sequences of two C2V-symmetric building blocks lead to the formation of four two-dimensional (2D) COFs with distinct framework structures. To verify this concept, target synthesis was conducted to produce three COFs, whose structures were confirmed by powder X-ray diffraction and pore size distribution analysis.

The bamboo grasshopper, Ceracris kiangsu Tsai, is a pest of bamboos and widely distributed in China from high temperature plains to low temperature plateaus. In this study, high-throughput sequencing was used to analyze the transcriptome of C. kiangsu. Approximately 129,314,084 reads were generated using an Illumina sequencing. De novo assembly yielded 39,013 unigenes with an average length of 987 bp. Based on sequence similarity searches with known proteins, a total of 19,769 (50.67%) unigenes were identified. Of these annotated unigenes, 2114 and 11,412 unigenes were assigned to clusters of orthologous groups and gene ontology, respectively. Furthermore, 2128 simple sequence repeats (SSRs) were identified in the unigenes Differences were observed in gene expression after hypothermic stress, with the most up-regulated genes including heat shock protein genes (Hsps) and genes involved in ATP-binding. The down-regulation of genes involved in the catalytic activity of metabolic mechanisms was also observed. The obtained transcriptome information revealed the ability of C. kiangsu to build cold-tolerance after exposed to a mild low temperature and the transcriptional responses elicited by hypothermic stress.

A tetraphenylethene-based 2D covalent organic framework (COF) has been synthesized. It exhibits a very fast response and high sensitivity to the presence of gaseous HCl by way of distinct changes in fluorescence emission and color, which makes the COF a good chemosensor for spectroscopic and naked-eye detection of gaseous HCl.

An efficient method of synthesizing 2-trifluoromethylindoles from indoles with easy-to-handle, cheap and low-toxic CF3SO2Na under metal-free conditions is described, which selectively introduces trifluoromethyl to indoles on the C2 position. The desired product can be obtained in 0.7 g yield. A radical intermediate may be involved in this transformation.

The direct regio- and enantioselective C6 functionalization of 2,3-disubstituted indoles with azadienes has been developed using chiral phosphoric acid as catalyst, providing a convenient approach to synthesize the optically active heterotriarylmethanes with excellent yields, broad substrate scope, and up to 98% ee. Mechanistic studies revealed that N-alkylation of 2,3-disubstituted indoles with azadienes would be reversible, and enantioselective C6 functionalization could be enabled.

Transformation between 2D covalent organic frameworks (COFs) via exchange of molecular building blocks with different symmetries has been realized, which gives rise to the conversion between 2D COFs with distinct pore hierarchy. This type of monomer replacement has expanded the scope of the building-unit-exchange-based COF-to-COF transformation strategy.

Studies of chemosensory genes are key to a better understanding of intra- and interspecific communications between insects and their environment and provide opportunities for developing environmentally friendly pesticides to target pest species. The bamboo locust Ceracris kiangsu Tsai (Orthoptera: Acrididae) is one of the most important bamboo leaf-eating insects in southern China. However, the genes underlying olfactory sensation are lacking in the bamboo locust. In this study, the transcriptomes of male and female C. kiangsu antennae were sequenced and analyzed. A total of 125 chemosensory genes, including 91 odorant receptors (ORs), 13 ionotropic receptors (IRs), 13 odorant-binding proteins (OBPs), six chemosensory proteins (CSPs), and two sensory neuron membrane proteins, were identified based on sequence alignment and phylogenetic analyses. The expression patterns of all candidate genes on the antennae of males and females, maxillary palps, tarsi, wings, and thoraxes-abdomens were confirmed by real-time quantitative PCR. The analyses demonstrated that most genes are highly expressed in the antennae, and 35 ORs, 7 IRs, 10 OBPs, and 1 CSP exhibit significantly male-biased expression patterns, indicating their potential functions in mating behavior and the recognition of female sex pheromones. In addition to the antennal-predominant genes, some were abundant in the maxillary palps and some in the non-olfactory tissues, suggesting their different functions in the olfactory system of C. kiangsu. Our research offers an extensive resource for investigating the chemoreception mechanism of C. kiangsu. Further studies of olfactory function will provide comprehensive methods and original strategies for integrated pest management.

An organocatalytic enantioselective 1,4-addition of phosphites to azadienes has been successfully developed using quinine as a catalyst, providing an efficient and facile route to optically active γ-aminophosphonates with up to 94% ee.

While significant progress in covalent organic frameworks (COFs) has been made in recent years, the construction of COFs with heterogeneous porosity remains a great challenge. In this communication, we report two novel 2D heteropore COFs which bear two kinds of hexagonal micropores with different shapes and sizes. They have been constructed by the condensation of monomers with C2v- and D3h-symmetry, and their structures have been confirmed by PXRD studies, synchrotron SAXS experiments, theoretical simulations and pore size distribution analyses.

The bamboo grasshopperCeracris fasciatais regarded as a major pest species because of the damage it causes to bamboo, and its classification within the families and subfamilies of the suborder Caelifera remains unclear. Thus, we attempted to resolve these questions using molecular biology methods and analyses. Our results are as follows: (1) the complete mitochondrial genome ofC. fasciatais 15,569 bp in length. The mitochondrial genome contains a standard set of 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and an A + T-rich region in the same order as those of the other analysed Caeliferan species. The putative start codon for theCOX1gene inC. fasciatais ACC, although it is not defined in other genes. The presence of tandem repeats of different sizes in the A + T-rich region may lead to size differences in other mitochondrial genomes. The mitochondrial genome ofC. fasciataharbours the typical 37 genes and an A + T-rich region, and it shows similar characteristics to those of other grasshopper species. Characterization of the mitochondrial genome has enriched our knowledge of the mitochondrial genomes of Orthoptera around the world. Therefore, the phylogenetic relationships in Orthoptera can be re-examined. (2) In phylogenetic analyses, the monophyly of Orthoptera and its two suborders (Caelifera and Ensifera) has been consistently recovered based on most of the datasets selected, regardless of the optimal criteria. Our results do not support the monophyly of the subfamily Oedipodinae of Caelifera. We found thatPhlaeoba albonemaof the Acridinae is sorted into a clade withCeracrisin all our phylogenetic trees, and field experiments show thatPhlaeobaalways lives withCeracrisin the same ecotopes. Therefore, we suggest thatPhlaeobashould be classified as a member of the Oedipodinae. We found thatC. fasciataalways clustered withCeracris kiangsu,and both were sisters toCeracris versicolor.Therefore, the genetic relationship betweenC. fasciataandC. kiangsuis closer than that betweenC. fasciataandC. versicolor.(3) The oldest estimated time of divergence of Ensifera in this context was determined to be 146.16 million years ago (Mya), or around the late Jurassic or early Cretaceous. We estimated that katydids (Grylloidea) likely diverged from other groups in the early Cretaceous. According to our divergence time analyses, we concluded that the ancestral Acrididae probably originated in the early Paleogene, and it is likely that the major diversification events happened at the middle Paleogene, well into the next geologic time. We estimated that crickets (Tettigoniidae) likely diverged from other groups in the early Cretaceous. Acrididae and Romaleinae group, Pyrgacrididae and Ommexechidae group, the youngest two clades we observed, were estimated to have diverged 58.79 Mya, between the middle and early Paleogene.C. versicoloris a sister to the group containingC. kiangsuandC. fasciata. First,C. versicolordiverged from the sister group (C. kiangsu+C. fasciata) around 44.81 Mya, and then theC. kiangsuandC. fasciatagroup separated at 43.04 Mya.

The di-tert-butyl peroxide (DTBP) induced coupling of arenesulfonylindoles with ethers such as 1,4-dioxane, tetrahydropyran, tetrahydrofuran, and 1,2-dimethoxyethane was studied. The distinguishing feature of this strategy was characterized by capturing in situ generated vinylogous imine intermediates for the C(sp3)–H bond alkylation of ethers. This general procedure presents the major advantages of its wide substrate scope and good functional group compatibility

An efficient method to synthesize isatins based on indoles by using inorganic hypervalent I 2 O 5 has been explored in good yields, which successfully realized the transformation from indoles to isatins under metal-free, mild condition with broad substrate scope.

Two novel covalent organic frameworks (COFs) bearing Kagome lattices have been fabricated through the condensations of a D2h symmetrical tetraaldehyde and C2 symmetrical aromatic diamines of various lengths.

Two-photon imaging, due to its unique advantage to utilize near-infrared light as the excitation source, has emerged as an important tool for biomedical research. Herein, the first NBD amine based two-photon fluorescence probe L using a FRET strategy was developed for detecting H2S in vitro and in vivo. The probe L not only afforded high selectivity and sensitivity for the detection of H2S, but also displayed a linear response to H2S with a low detection limit of 24 nM. Furthermore, the living cell experiments indicated that L can be effective for the both exogenous and endogenous detection of H2S inside living cells by two-photon fluorescence imaging.

An efficient access to optically active sulfahydantoins, 4-aryl-1,2,5-thiadiazolidin-3-one 1,1-dioxides, was developed through palladium-catalyzed asymmetric hydrogenation of the corresponding cyclic N-sulfonylketimines with up to 98% ee.

An efficient method of synthesizing 2-trifluoromethylindoles from indoles with easy-to-handle, cheap and low-toxic CF

BackgroundThe Lepidoptera is one of the largest insect orders. Previous studies on the evolution of Lepidoptera did not confidently place butterflies, and many relationships among superfamilies in the megadiverse clade Ditrysia remain largely uncertain. Here, we generated a molecular dataset with 78 species of lepidopterian insects, including a new complete mitochondrial genome (mitogenome) sequences of the Golden Birdwing Butterfly,Troides aeacus,which was listed in appendix II of CITES.MethodsBased on the concatenated nucleotide sequences of 13 protein-coding genes, we constructed phylogenetic trees with Bayesian Inference (BI) and Maximum Likelihood (ML) methods, and calculated the divergence times of Lepidoptera.ResultsMonophyly of the Papilionoidea including skippers (Hesperiidae) is strongly supported by a high bootstrap value. Butterflies were placed sister to the remaining obtectomeran Lepidoptera, and the latter was grouped with high bootstrap supports. Additionally, Papilionidae probably diverged from the group (Hesperiidae + (Nymphalidae + Pieridae)) at 102.65 Mya, the Early Cretaceous.T. aeacusand the Golden kaiserihindTeinopalpus aureusdiverged in the Cretaceous of 85.32 Mya. The age of Papilionoidea indicates that the primary break up of Gondwana may have an effect on the current distributions of butterflies.

Aqueous zinc-ion hybrid capacitors (ZIHCs) are promising energy storage devices for grid-scale energy storage due to the low cost, intrinsic non-flammability, environmental friendliness, and high power densities. Currently, most reported ZIHCs employed zinc metals as anodes. However, uncontrollable Zn dendrite growth and the huge volume change of Zn metal anode during the stripping/plating process greatly hinder the practical application of ZIHCs. Thus, it is highly desirable to develop alternative anode materials with favorable electrochemical performances. Herein, we demonstrate a polymer from polyarylimide and porphyrin as a new anode material for ZIHCs. The Zn ion storage electrochemistry in this porous organic polymer-tetra(4-aminophenyl)porphyrin-1,4,5,8-naphthalenetetracarboxylic dianhydride (POP-TAPP-NTCA) is investigated by cyclic voltammetry analysis, galvanostatic charge/discharge measurement, electrochemical impedance spectroscopy, kinetic analysis, and density functional theory calculation. The fabricated ZIHC based on POP-TAPP-NTCA anode exhibits an energy density of 48 Wh kg−1 and capacitance retention of 90% after 1100 cycles. This work will inspire the exploration of new anode materials for Zn ion storage and facilitate the development of safe electrochemical energy storage.

Integrating different kinds of pores into one covalent organic framework (COF) endows it with hierarchical porosity and thus generates a member of a new class of COFs, namely, heteropore COFs. Whereas the construction of COFs with homoporosity has already been well developed, the fabrication of heteropore COFs still faces great challenges. Although two strategies have recently been developed to successfully construct heteropore COFs from noncyclic building blocks, they suffer from the generation of COF isomers, which decreases the predictability and controllability of construction of this type of reticular materials. In this work, this drawback was overcome by a multiple-linking-site strategy that offers precision construction of heteropore COFs containing two kinds of hexagonal pores with different shapes and sizes. This strategy was developed by designing a building block in which double linking sites are introduced at each branch of a C3 -symmetric skeleton, the most widely used scaffold to construct COFs with homogeneous porosity. This design provides a general way to precisely construct heteropore COFs without formation of isomers. Furthermore, the as-prepared heteropore COFs have hollow-spherical morphology, which has rarely been observed for COFs, and an uncommon staggered AB stacking was observed for the layers of the 2D heteropore COFs.

A chiral phosphoric acid-catalyzed asymmetric transfer hydrogenation of 3-trifluoromethylthioquinolines has been successfully developed, providing direct and facile access to chiral 2,3-disubstituted 1,2,3,4-tetrahydroquinoline derivatives containing a stereogenic trifluoromethylthio group with up to 99% enantioselectivity.

A strategy to construct covalent organic frameworks (COFs) bearing two different kinds of pores has been developed, by which two dual-pore COFs were fabricated through the condensation reactions of two D2h symmetrical building blocks. The COFs exhibit good adsorption capacities for CO2 and H2.

A bifunctional squaramide-catalyzed reaction of pyrazolin-5-ones with o-quinone methides in situ generated from 2-(1-tosylalkyl)phenols has been successfully developed, providing a facile access to chiral pyrazolones with high enantioselectivities. In addition, the chiral spiropyrazolones with adjacent tertiary and quaternary stereogenic centers can also be obtained through cascade chlorination/cyclization of the chiral pyrazolones.

The bamboo grasshopper Ceracris kiangsu is a famous bamboo pest in China. The identification of genes involved in olfactory behavior of C. kiangsu is necessary for better understanding the molecular basis and expression profiles of behavior ecology. However, necessary genomic and transcriptomic data are lacking in the species, limiting control efficiency. The primary objective of this study was to find and describe odorant binding proteins in the head of the bamboo grasshopper. We performed the paired-end sequencing on an Illumina Hiseq2000 following the vendor’s recommended protocol. Functional annotation was performed by comparison with public databases. OBP genes were first identified using BLASTN and BLASTX results from our C. kiangsu datebase, which was established from the date of transcriptome sequencing. The gene-specific primers were used to conduct RT-PCR to detect the tissue distribution of OBPs using a SYBR Premix ExTaq kit following the manufacturer’s instructions with a real-time thermal cycler. We obtained more than 133 million clean reads derived from the C. Kiangsu heads using the next-generation sequencing, which were assembled into 260,822 unique sequences (average 814 bp). We have detected eight putative odorant binding protein genes (OBPs) of C. kiangsu for the first time, and analyzed the expression profiles of the OBPs in different tissues (head, antenna, mouthpart, body and leg). Our results reveal that the eight OBPs display a clear divergence, strongly indicating that they possessed diverse functions, and thus provides comprehensive sequence analysis for elucidating the molecular basis of OBPs in C. kiangsu. In addition, we find that the relative expression levels of OBP1, OBP2 and OBP8 are significantly higher in the antennae as compared to the other OBP genes, suggesting that these three OBP genes play crucial roles in the locust’s odorant discrimination. In general, this is the first study to characterize the complete head transcriptome of C. kiangsu using high-throughput sequencing. The study opens a window for functional characterization of the OBPs of C. kiangsu, with potential for new or refined applications of semiochemicals for control of this notorious pest.

Ribosomal protein S23 (RPS23) constitutes the ribosomal binding site for mRNA in the 40S initiation complex, and appears to be involved in initiating the translation of messenger RNA into protein (translation step). In this study, a full-length of RPS23 cDNA was cloned from the American cockroach, Periplaneta americana (L.) (Blattodea: Blattidae) by using rapid amplification of cDNA ends (RACE) approaches. The full-length cDNA of the P. americana RPS23 (PaRPS23) was of 615 bp, containing a 5′ untranslated region (UTR) of 116 bp, a 3′ UTR of 67 bp with a poly (A) tail, and an open reading frame of 432 bp encoding a polypeptide of 143 amino acids with the predicted molecular weight of 16.03 kDa and estimated isoelectric point of 10.47 (NCBI accession number: KJ472479). BLAST analysis revealed that amino acids of PaRPS23 shared identity with Graphocephala atropunctata (Signoret) 99%, (Hemiptera: Cicadellidae), Tribolium castaneum (Herbst) 99%, (Coleoptera: Tenebrionidae), Pediculus humanus corporis ...

Copper porphyrin-catalyzed Glaser–Hay-type couplings of terminal alkynes generating 1,3-diynes are described. This reaction features high TON (up to 950) and is complete in an hour, providing a facile, clean, and efficient protocol to access various 1,3-diynes including those with functional groups under mild reaction conditions. This transformation would take place via a radical process.

A bifunctional squaramide-catalyzed reaction of azlactones with o-quinone methides in situ generated from 2-(1-tosylalkyl)-phenols has been successfully developed under basic conditions, providing an efficient and mild access to chiral dihydrocoumarins bearing adjacent tertiary and quaternary stereogenic centers in high yields with excellent diastereo- and enantioselectivities.

Most of grasshoppers in the family Oedipodidae are the famous agriculture pests in China. However monophyly and the relationships among the subfamilies within this family are unclear up to now. Here the phylogeny of the Oedipodidae was reconstructed based on 16S rDNA sequence fragments by using Mekongiella kingdoni and Atractomorpha sinensis as outgroups under weighted MP, NJ and Bayesian criteria. The 408 bp fragments of mitochondrial 16S rRNA gene were sequenced for 15 species from 4 subfamilies of the family Oedipodidae, and the homologous sequences of other 15 species of grasshoppers were downloaded from the GenBank data library. The numbers of transitions and transversions among pairwise comparisons of the 16S fragments were respectively plotted against percentage sequence differences. Saturation of transitions was discovered, and transversions were not saturated with the increase of percentage sequence difference in the plots. All the individuals of the Oedipodidae excluding Trilophidia annulata were gathered together in the three trees. Our results are very different from the traditionary taxonomy of the Oedipodidae including 4 subfamilies. The Bryodemellinae is not supported as a subfamily, and neither Locustinae nor Oedipodinae are supported as a monophyletic group in this study.

A new visible-light promoted strategy for the difunctionalization of activated alkenes with two C–H bonds has been developed. In the presence of [Ru(bpy)3Cl2], 4-MeOC6H4N2BF4, Na2CO3 and 36 W compact fluorescent light, a variety of N-arylacrylamides underwent the 1,2-alkylarylation reaction with acetonitrile or acetone to give the corresponding functionalized oxindoles in moderate to good yields.

A chiral phosphoric acid-catalyzed asymmetric transfer hydrogenation of 3-trifluoromethylthioquinolines has been successfully developed, providing direct and facile access to chiral 2,3-disubstituted 1,2,3,4-tetrahydroquinoline derivatives containing a stereogenic trifluoromethylthio group with up to 99% enantioselectivity.

The Henry reaction of aromatic aldehydes and nitroalkanes could be performed by catalyst of Lipase A from Aspergillus niger in organic/water medium, and the corresponding Henry products were obtained in yields up to 94%.

Studies on the cockroach have contributed to our understanding of several important developmental processes, especially those that can be easily studied in the embryo. However, our knowledge on late events such as gonad differentiation in the cockroach is still limited. The major aim of the present study was to identify sex-specific genes between adult female and male Periplaneta americana. Two cDNA libraries were constructed using the suppression subtractive hybridization method; a total of 433 and 599 unique sequences were obtained from the forward library and the reverse library, respectively, by cluster assembly, and sequence alignment of 1,032 expressed sequence tags. The analysis of the differentially expressed gene functions allowed these genes to be categorized into three groups: biological process, molecular function, and cellular component. The differentially expressed genes were suggested to be related to the development of the gonads of P. americana. Twelve differentially expressed genes were randomly selected and verified using relative quantitative real-time polymerase chain reaction (qRT-PCR). Meanwhile, by adopting a range of filtering criteria, we predicted two potential microRNA sequences for P. americana, pam-miR100-3p and pam-miR7. To confirm the expression of potential microRNAs (miRNAs) in American cockroach, a qRT-PCR approach was also employed. The data presented here offer the insights into the molecular foundation of sex differences in American cockroach, and the first report for the miRNAs in this species. In addition, the results can be used as a reference for unraveling candidate genes associated with the sex and reproduction of cockroaches.

To explore the response of the soil microbial community to nitrobenzene (NB) exposure in a Spartina marsh, a short-term (45 d) mesocosm study was conducted at three NB concentrations of (10, 50, and 100) mg kg−1. Dry soil, sterile and unsterile controls were also compared. The ability of the microbes to biodegrade NB was studied in an effort to predict the outcome of NB in the mesocosm. The results indicated that a microbial community is capable of doing so. Microbial enumeration and enzyme assays showed that the fluctuations in microbial communities and polyphenol oxidase activities are related to the initial NB concentration. Moreover, cluster analyses through denaturing gradient gel electrophoresis (DGGE) revealed very similar patterns (95.5%) throughout the 45 d term, indicating that the microbial community regenerates when NB is exhausted. Although volatilization and photolysis were the major processes responsible for the reduction in NB in contaminated mesocosms and the microbial community regenerat...

A green and convenient protocol has been developed for asymmetric cross-aldol reaction. In this Letter, bovine pancreatic lipase (BPL) was first reported to catalyze the aldol reaction and acidic buffer was first used for promiscuous enzymatic aldol reaction.