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Forested wetlands are an integral but understudied part of heterogeneous landscapes in Atlantic Canada, although they are known to provide habitat for species at risk. Our objectives were to explore patterns of forest structure across edges between forested wetland and upland forest, to locate changes in vegetation structure and to assess multivariate relationships in vegetation structure. Our study sites were in temperate (Acadian) forested wetland landscapes. We sampled trees and recorded canopy cover every 20 m along 120-m-long transects. We estimated the cover of trees, saplings, shrubs in three height classes, Sphagnum, other bryophytes, lichens, graminoids, ferns, and forbs in contiguous 1 m × 1 m quadrats. We calculated structural diversity using the Shannon index and used wavelet analysis to assess spatial patterns. We found few clear patterns except for lower tree structural diversity at the edge of forested wetlands. Structural diversity was not a reliable measure for distinguishing forested wetland from upland forest. Forested wetlands are an integral part of many forested landscapes in Atlantic Canada, but their detection and differentiation from surrounding ecosystems can be difficult. Policy should err on the side of caution when mapping forested wetlands and include them in wetland protection.

Over 3 billion years, photosynthetic algae have evolved complex uses for cellulose, the most abundant polymer worldwide. A major cell-wall component of lignocellulosic plants, seaweeds, microalgae, and bacteria, cellulose can be processed to nanocellulose, a promising nanomaterial with novel properties. The structural diversity of macro- and microalgal nanocelluloses opens opportunities to couple low-impact biomass production with novel, green-chemistry processing to yield valuable, sustainable nanomaterials for a multitude of applications ranging from novel wound dressings to organic solar cells. We review the origins of algal cellulose and the applications and uses of nanocellulose, and highlight the potential for microalgae as a nanocellulose source. Given the limited state of current knowledge, we identify research challenges and strategies to help to realise this potential.

Two undescribed shikimic acid derivatives named shikimerans B and C (1 and 2), one new natural compound shikimeran D (3), as well as five known compounds 4−8 were obtained from the EtOAc extract of the endophytic fungus Chaetomium sp. FZ-4. Their structures were determined by the NMR spectroscopy and HRESIMS examination, while the absolute configurations of compounds 1−3 were clarified based on the electronic circular dichroism (ECD) experiment. These new compounds enriched the structural diversity of shikimic acid analogues and also expanded the chemical diversity of the metabolites of Chaetomium sp..

Distributions of branched glycerol dialkyl glycerol tetraethers (brGDGTs) are frequently employed for reconstructing terrestrial paleotemperatures from lake sediment archives. Although brGDGTs are globally ubiquitous, the microbial producers of these membrane lipids remain unknown, precluding a full understanding of the ways in which environmental parameters control their production and distribution. Here, we advance this understanding in three ways. First, we present 43 new high-latitude lake sites characterized by low mean annual air temperatures (MATs) and high seasonality, filling an important gap in the global dataset. Second, we introduce a new approach for analyzing brGDGT data in which compound fractional abundances (FAs) are calculated within structural groups based on methylation number, methylation position, and cyclization number. Finally, we perform linear and nonlinear regressions of the resulting FAs against a suite of environmental parameters in a compiled global lake sediment dataset (n = 182). We find that our approach deconvolves temperature, conductivity, and pH trends in brGDGTs without increasing calibration errors from the standard approach. We also find that it reveals novel patterns in brGDGT distributions and provides a methodology for investigating the biological underpinnings of their structural diversity. Warm-season temperature indices outperformed MAT in our regressions, with the mean temperature of months above freezing yielding the highest-performing model (adjusted R2 = 0.91, RMSE = 1.97 ∘C, n = 182). The natural logarithm of conductivity had the second-strongest relationship to brGDGT distributions (adjusted R2 = 0.83, RMSE = 0.66, n = 143), notably outperforming pH in our dataset (adjusted R2 = 0.73, RMSE = 0.57, n = 154) and providing a potential new proxy for paleohydrology applications. We recommend these calibrations for use in lake sediments globally, including at high latitudes, and detail the advantages and disadvantages of each.

Silvicultural practices, effective fire suppression, and increased browser densities have profoundly altered structural diversity in boreal forests. Prescribed burning and retention forestry may counteract losses in structural diversity in managed forests by maintaining a higher deciduous admixture. We constructed an experiment on 18 sites with three types of timber harvesting (uncut, cut with retention, and clearcut) and burned half of these sites. Subsequently, we established a herbivore treatment with three compartments (unfenced, fenced excluding moose (Alces alces (Linnaeus, 1758)), and fenced excluding moose and hares (Lepus spp.)). In these compartments, we planted rowan (Sorbus aucuparia L.), European aspen (Populus tremula L.), and silver birch (Betula pendula Roth) seedlings and monitored these for 17 years. Birch and rowan mortality were lower on cut and burned sites, with retention further enhancing birch survival on these sites. Retention without burning did not lower seedling mortality of any tree species. While browsing resulted in greater mortality on cut sites, burning appeared to greatly reduce browsing on birch and rowan. On mature uncut sites, seedlings of all tree species exhibited high mortality. Our findings show that deciduous tree recruitment can be improved through prescribed burning, particularly for birch and rowan, and that browsing impacts on deciduous trees depend on forest age.

d/l-Hybrid peptides are an attractive class of molecular modality because they are able to exhibit high proteolytic stability and unique structural diversity which cannot be accessed by those consisting of only proteinogenic l-amino acids. Despite such an expectation, it has not been possible to devise de novo d/l-hybrid peptides capable of disrupting the function of a protein target(s) due to the lack of an effective method that reliably constructs a highly diverse library and screens active species. Here we report for the first time construction of a library consisting of 1012 members of macrocyclic d/l-hybrid peptides containing five kinds of d-amino acids and performance of the RaPID selection against human EGFR as a showcase to uncover PPI (protein-protein interaction) inhibitors.

The catalytic enantioselective synthesis of α-chiral olefins represents a valuable strategy for rapid generation of structural diversity in divergent syntheses of complex targets. Herein, we report a protocol for the dual CuH- and Pd-catalyzed asymmetric Markovnikov hydroalkenylation of vinyl arenes and the anti-Markovnikov hydroalkenylation of unactivated olefins, in which readily available enol triflates can be utilized as alkenyl coupling partners. This method allowed for the synthesis of diverse α-chiral olefins, including tri- and tetrasubstituted olefin products, which are challenging to prepare by existing approaches.

Atropisomerism is a stereochemical behavior portrayed by three-dimensional molecules that bear rotationally restricted σ bond. Akin to the well-represented point-chiral molecules, atropisomerically chiral compounds are finding increasing utilities in many disciplines where molecular asymmetry is influential. This provides steady demand on atroposelective synthesis, where numerous synthetic pursuits have been rewarded with conceptually novel and streamlined methods while expanding the structural diversity of atropisomers. This review summarizes key achievements in stereoselective preparation of biaryl, heterobiaryl, and nonbiaryl atropisomers documented between 2015 and 2020. Emphasis is placed on the synthetic strategies for each structural class, while examples are cited to illustrate the potential applications of the accessed atropochiral targets.

Understanding diversity-productivity relationships (DPRs) is of theoretical importance and has practical implications for biodiversity conservation and forest management. Although the effects of sp...

Hybrid organic–inorganic halogenidocuprates based on copper(I) represent materials with rich structural diversity and high photoluminescence (PL) quantum yield, yet the mechanism responsible for th...

Natural arylnaphthalene lactones are representative lignans that are found in various dietary and medicinal plants. Their unique structural features and significant pharmacological activity have attracted considerable attention from both synthetic and medicinal chemists. Owing to their unique structural features such as relative rigid tetracyclic skeleton, structural diversity of more than five substituents, and no chiral center, arylnaphthalene lactones are recognized as a valuable scaffold for drug discovery, in addition to their significant pharmacological activities. This review covers the structures and isolation of all naturally occurring arylnaphthalene lactone congeners reported. Based on the aryl substituents, they were categorized as Type I and Type II and further classified according to the oxidation state of the ring and glycosylation level. Special attention has been paid to natural arylnaphthalene lactones owing to their broad spectrum of biological activities such as cytotoxic, antiplatelet, antiviral, anti-HIV, antifungal, neuroprotective, and anti-inflammatory properties. All the products were reorganized based on their biological activities, and selected data are presented.

The Qinling-Daba Mountains are the main body of China’s North-South Transitional Zone. Analysis of the north-south gradual variation of vegetation components is significant for understanding the structural diversity and complexity of this transitional zone. In this study, based on survey data of plant communities, the eastern Qinling-Daba Mountains is divided into four geographic units: the north flank of eastern Qinling Mts., south flank of eastern Qinling Mts., north flank of eastern Daba Mts. and south flank of eastern Daba Mts. We also explore division of regional climate according to areal differentiation of plant-species, community structure and species-richness, respectively. The results show that, (1) at plant-species level, there are mainly northern plants in north flank of eastern Qinling Mts. with evergreen species and fewer northern plants in south flank of eastern Qinling Mts.; there are mainly southern plants in eastern Daba Mts. (2) At community structure level, there are 4 formations (3 northern formations and 1 widespread formation) in north flank of eastern Qinling, 6 formations (3 northern formations, 1 southern formation, and 2 widespread formations) in south flank of eastern Qinling, 4 formations (2 southern formations and 2 widespread formations) in north flank of eastern Daba Mts., and 3 formations (3 southern formations) in south flank of eastern Daba Mts. In terms of the numbers and properties of formations, there is a mixture of northern and southern formations only in the south flank of eastern Qinling Mts. (3) At species-richness level, the diversity of families, genera and species decreased with increasing latitude, but the mixing of northern plants and the southern plants began to occur in south flank of eastern Qinling Mts. This means that the south flank of the eastern Qinling Mts. serves more suitably as the dividing line between China’s warm temperate and subtropical zones.

The genus Selaginella belongs to the family Selaginellaceae, which is well known for its unique structural classes of natural products and their wide range of biological effects. This review provides a comprehensive list of unique secondary metabolites isolated from the genus Selaginella and also provides insight into their important biological activities. For the benefit of the readers, this review is divided into two main sections. The first section elaborates on the natural products isolated from Selaginella, with the emphasis on compounds exclusive to this genus, while the second section provides an in-depth discussion of a number of different pharmacological activities that the compounds and Selaginella extracts exhibited.

Multicomponent reactions (MCRs) are a valuable tool in diversity-oriented synthesis. Its application to privileged structures is gaining relevance in the fields of organic and medicinal chemistry. Isatin, due to its unique reactivity, can undergo different MCRs, affording multiple interesting scaffolds, namely oxindole-derivatives (including spirooxindoles, bis-oxindoles and 3,3-disubstituted oxindoles) and even, under certain conditions, ring-opening reactions occur that leads to other heterocyclic compounds. Over the past few years, new methodologies have been described for the application of this important and easily available starting material in MCRs. In this review, we explore these novelties, displaying them according to the structure of the final products obtained.

The triazole heterocycle is a privileged scaffold in medicinal chemistry, since its structure is present in a large number of biologically active molecules, including several drugs currently in the market. Due to their vast applications, a wide variety of methods are described for their preparation, such as the 1,3-dipolar cycloaddition and processes involving diazo compounds and diazo transfer reactions. Considering the significant number of contributions from our research group to this chemistry in recent decades, in this account we discuss both the development of new methods for the synthesis of 1,2,3-triazoles and the preparation of new triazole-functionalized biologically active molecules using classical approaches.

Reaction of a phosphane-decorated benzenedithiol (pbdtH(2)) with coinage metal salts furnished polynuclear complexes [M-2(pbdtH)(2)] (M=Au-I) or [cat][M-5(pbdt)(3)] (cat=unipositive cation, M=Ag-I, Cu-I), which were characterized by analytical and spectroscopic techniques and single-crystal X-ray diffraction studies. Furthermore, a double salt with an anion [Ag-5(pbdt)(3)(PPh3)](-) that proved unstable in solution was characterized crystallographically. The spectroscopic and crystallographic data revealed that the Cu(I) and Ag(I) complexes exhibit, despite their like stoichiometric composition, isomeric molecular structures. The observed disparities were reproduced by DFT studies. The dinuclear Au(I) complex was found to undergo air-oxidation to furnish a mixed-valent complex [(Au-III)(2)(Au-I)(2)(pbdt)(4)]. The copper(I) - but not the isomeric silver(I) complexes - showed luminescence in the solid state.

Compound libraries with high levels of structural diversity and novelty could cover underexploited chemical space and thus have been highly pursued in drug discovery. Herein, we report the first Cu(OTf)2-catalyzed intramolecular radical cascade reactions that enable the diversity-oriented synthesis of quinoline-annulated polyheterocyclic compounds (7 unique scaffolds, 66 examples) in an efficient manner. This work demonstrates an alternative route to access the natural product- and druglike compound collection with high levels of structural diversity and novelty.

The potential of “customizable units” to generate structural diversity for biological screenings is highlighted in this proof‐of‐concept synthesis of new peptides related to the potent antitumoral Sansalvamide A. Using L‐4‐hydroxyproline (Hyp) as a customizable unit in a linear parent peptide, an improved procedure for selective peptide modification was developed. A divergent Hyp scission‐reductive amination process was carried out, affording five linear peptides with cationic residues, and notably, an N‐alkyl moiety that affected the conformation of the peptide. After two steps (saponification and macrocyclization), sixteen differently N1‐substituted linear and cyclic peptides were obtained. For the first time, the activity of the linear and cyclic compounds was compared. Not only some linear analogs but also cyclic compounds with scarcely studied cationic residues were active against MCF7 breast cancer line. Thus, the structural diversity generated from customizable units can be valuable in drug discovery., This work was partly financed by the Consejo Nacional de Ciencia y Tecnología (CONACYT, Mexico) through project 2015‐01‐807, and by MINECO‐MCIU (Spain) with European Social Funds (ESF), through Programme Plan Estatal I+D‐RETOS (project SAF‐2013‐48399‐R). C. J. S. received a postdoctoral contract from the Torres Quevedo Programme (PTQ15‐07923) by MINECO/Min. Science and Innovation, cofinanced by BIOSIGMA SL. Finally, I.R−E. and F.C. thank CONACYT for Catedra contract 942 and predoctoral grant 305283 respectively.

International audience; Porphyrins and N-heterocyclic carbenes (NHCs) are both relevant ligands in the fields of coordination and organometallic chemistry. Despite evident structural differences, porphyrins and NHCs have a lot in common such as their ability to form strong metalligand bonds and their use in catalysis, materials science and biomedicine. During the last decade, several molecular systems combining porphyrins and NHC ligands were reported in the literature. The present review gathers relevant examples where NHC ligands are either axially bonded to metalloporphyrins or covalently attached to the porphyrin cores. Structural diversity, electronic interplay between porphyrins and NHCs and some relevant applications in catalysis and biomedicine are notably described. Finally, molecular systems combining NHCs with other original porphyrinoids such as Nconfused porphyrins, subporphyrins and norcorroles are also presented.

Conversion of the numerous aryl ketones into aryl electrophiles via Ar–C(O) cleavage remains a challenging yet highly desirable transformation in Sonogashira-type coupling. Herein, we report a pall...

The stereoselective synthesis of terminal bromo-substituted propargylamines via in situ generation of lithium bromoacetylide from 1,2-dibromoethene and addition to Ellman chiral N-tert-butanesulfinyl aldimines is reported. Modest to good yields (43-85%) and diastereoselectivity (dr = 3:1 to >20:1) were achieved for a range of aryl, heteroaryl, alkyl, and α,β-unsaturated substrates. Terminal bromo-substituted propargylamines prepared via this method can be directly used in the frequently employed Cadiot-Chodkiewicz coupling to produce functionalized diynes. The method reported here increases the structural diversity of chiral terminal bromo-substituted propargylamines that can be readily synthesized as previous methods for the stereoselective synthesis of these compounds rely on amino acid precursors from the chiral pool.

Transition metal (T) nitroprussides form a family of coordination complexes with a wide structural diversity including 3 D, 2 D, 1 D, 0 D and ionic phases. Recently, a reversible thermally induced spin transition has been reported for 2 D ferrous nitroprussides stabilized through pyridine and its derivatives as pillars between neighboring layers. The aim of this study is to explore the possibility of obtaining analog solids with spin-crossover behavior using other molecules as pillars. In this contribution we are reporting the crystal structure, solved and refined from powder XRD data, for the resulting hybrid solids containing 1,3-oxazole, 1H-pyrazole, pyridazine, 3-pyridine-3-carboxaldheyde, imidazo[1,2-a]pyridine, and 4-(2-pyridin-4-ylethyl)pyridine as pillar molecules in the interlayer region. The XRD data were complemented with TG curves, and IR, Raman, Mössbauer spectra, and magnetic measurements as a source of complementary structural information. According to the Mössbauer spectra and magnetic data recorded in the temperature range of 5 to 300 K, no evidence of thermally induced spin-crossover was observed for the 2 D ferrous nitroprussides with these six organic ligands as pillars. Such behavior is in contrast with the one observed for pyridine and its derivatives and it is explained in terms of the local symmetry around the high spin Fe2+ ion, as revealed in the recorded Mössbauer spectra. This suggests that the spin-crossover behavior could be induced by introducing guest molecules, as adsorbed species, in the interlayer region to force to a higher symmetry for the iron ion coordination environment.

In the last decade the prevalence of diabetes has escalated globally and it is estimated that the number of diabetic people will increase to 642 million by 2040. Although numerous classes of pharmaceutical drugs are available to treat Type ll diabetes, they manifest certain side effects. PTP1B has attracted significant interest as an important therapeutic agent and has been validated to target diabetes and obesity. Fungi, in general, produce secondary metabolites with some amazing chemical and structural diversity and are recognized to be a valuable source for therapeutic molecules. In this review, the focus is on describing the PTP1B effects and their potential as anti-diabetic agents for the various metabolites isolated from fungi.

We studied the cascade nucleophilic addition reactions of 1,2,3-triazines with activated acetonitriles or ketones, which were used to construct highly substituted pyridines that are not easily accessed by conventional methods. The strategy addressed some structural diversity issues currently facing medicinal chemistry, and the resulting pyridines could be used as convenient precursors for the synthesis of related pharmaceuticals. In particular, our method was applied to the syntheses of the marketed drug etoricoxib and several biologically important molecules in a few steps.

Nonribosomal peptides (NRP) are crucial molecular mediators in microbial ecology and provide indispensable drugs. Nevertheless, the evolution of the flexible biosynthetic machineries that correlates with the stunning structural diversity of NRPs is poorly understood. Here, we show that recombination is a key driver in the evolution of bacterial NRP synthetase (NRPS) genes across distant bacterial phyla, which has guided structural diversification in a plethora of NRP families by extensive mixing and matching of biosynthesis genes. The systematic dissection of a large number of individual recombination events did not only unveil a striking plurality in the nature and origin of the exchange units but allowed the deduction of overarching principles that enable the efficient exchange of adenylation (A) domain substrates while keeping the functionality of the dynamic multienzyme complexes. In the majority of cases, recombination events have targeted variable portions of the Acore domains, yet domain interfaces and the flexible Asub domain remained untapped. Our results strongly contradict the widespread assumption that adenylation and condensation (C) domains coevolve and significantly challenge the attributed role of C domains as stringent selectivity filter during NRP synthesis. Moreover, they teach valuable lessons on the choice of natural exchange units in the evolution of NRPS diversity, which may guide future engineering approaches.

Polyether polyols as a crucial chemical for the synthesis of polyurethanes have attracted much attention, especially for propylene oxide-based polyether polyols due to their ready availability and good structural diversity. In the present work, microreactors configured with a SIMM-V2 micromixer and stainless steel capillary were developed for the continuous and efficient synthesis of propylene oxide-based polyether polyols. For the conversion of propylene oxide higher than 95%, the reaction time was less than 60 s that was significantly shorter than that in a batch reactor. Also, the reaction temperature can be controlled precisely, thereby obtaining high purity polyether polyol products. To identify the maximum performance of the microreactors, while keeping the conversion of PO higher than 95%, the novel process windows of the reactors were determined by investigating the relations of reaction temperature and pressure, reaction temperature and residence time, and feed flow rate and residence time. The results showed that high quality polyether polyols could be easily prepared in the microreactors under flexible operating conditions. In addition, polyether polyols with higher molecular weights could also be prepared by using a two SIMM-V2 configured microreactor. This work showed that the microreactors are promising candidates for the synthesis of polyether polyols in the industry.

This study brings insight into interpreting forest structural diversity and explore the classification of individuals according to the distribution of the neighbours in natural forests. Natural forest communities with different latitudes and distribution patterns in China were used. Each tree and its nearest neighbours form a structural unit. Random structural units (or random trees) in natural forests were divided into different sub-types based on the uniform angle index (W). The proportions of different random structural units were analysed. (1) There are only two types of random structural units: type R1 looks similar to a dumbbell, and type R2 looks similar to a torch. These two random structural units coexist in natural forests simultaneously. (2) The proportion of type R1 is far less than that of R2, is only approximately 1/3 of all random structural units or random trees; R2 accounts for approximately 2/3. Furthermore, the proportion of basal area presents the same trend for both random structural units and random trees. R2 has approximately twice the basal area of R1. Random trees (structural units) occupy the largest part of natural forest communities in terms of quantity and basal area. Meanwhile, type R2 is the largest part of random trees (structural units). This study finds that the spatial formation mechanism of natural forest communities which is of great significance to the cultivation of planted forests.

A Ni-catalyzed direct C–H alkylation of N-quinolylbenzamides using alkylsilyl peroxides as alkyl-radical precursors is described. The reaction forms a new C(sp3)–C(sp2) bond via the selective cleavage of both C(sp3)–C(sp3) and C(sp2)–H bonds. This transformation shows a high functional-group tolerance and, due to the structural diversity of alkylsilyl peroxides, a wide range of alkyl chains including functional groups and complex structures can be introduced at the ortho-position of readily available N-quinolylbenzamide derivatives. Mechanistic studies suggest that the reaction involves a radical mechanism.

Covering: up to 1 October 2020 Solanum steroidal glycoalkaloids (SGA), characterized by nitrogenous steroidal aglycone and glycoside residues, mainly occur in the Solanum species, including economically important edible plants such as potato, tomato, and eggplant. To date, 107 SGA assigned to six total skeletons have been identified from Solanum plants. SGA have unique structures and display significant pharmacological activities such as cytotoxic, antimicrobial, anticholesterol, and some are well-known poisons. The biosynthesis pathway, transcriptional regulation, and the evolution of SGA are also examined in detail. This report updates the chemical knowledge of the naturally occurring SGA from Solanum species, thereby providing an in-depth analysis of their diversity, biological activities, and biosynthesis.

Lithium–sulfur (Li–S) batteries have emerged as promising energy storage devices due to their high theoretical specific energy densities; their practical applications, however, have been restricted due to their poor cycling stability arising from the shuttle effect of the S cathode and dangerous Li dendrite growth. S and Li can be encapsulated into porous framework hosts to address these issues. Metal–organic frameworks (MOFs)/covalent-organic frameworks (COFs) have shown great potential due to their tunable frameworks, structural diversity, and functional versatility. In this review, the applications of MOFs/COFs for Li–S batteries in terms of the sulfur hosts, electrolyte containers, separators, and Li dendrite blocking barriers are systematically summarized. A short conclusion and outlook regarding future research opportunities for pristine MOFs/COFs for Li–S batteries are also provided.

Background Forests perform various important ecosystem functions that contribute to ecosystem services. In many parts of the world, forest management has shifted from a focus on timber production to multi-purpose forestry, combining timber production with the supply of other forest ecosystem services. However, it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem services. Based on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition, we develop models to predict the potential supply of 13 ecosystem services. We use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory data. Results Looking at the potential supply of ecosystem services, we found trade-offs (e.g. between both bark beetle control or dung decomposition and both productivity or soil carbon stocks) as well as synergies (e.g. for temperature regulation, carbon storage and culturally interesting plants) across the 53 most dominant forest types in Germany. No single forest type provided all ecosystem services equally. Some ecosystem services showed comparable levels across forest types (e.g. decomposition or richness of saprotrophs), while others varied strongly, depending on forest structural attributes (e.g. phosphorous availability or cover of edible plants) or tree species composition (e.g. potential nitrification activity). Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental conditions. However, the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree species. Conclusions Our results show that forest multifunctionality is limited to subsets of ecosystem services. The importance of tree species composition highlights that a lack of multifunctionality at the stand level can be compensated by managing forests at the landscape level, when stands of complementary forest types are combined. These results imply that multi-purpose forestry should be based on a variety of forest types requiring coordinated planning across larger spatial scales.

Current commercial batteries cannot meet the requirements of next-generation technologies, meaning that the creation of new high-performance batteries at low cost is essential for the electrification of transport and large-scale energy storage. Solid-state batteries are being widely anticipated to lead to a step improvement in the performance and safety of batteries and their success is heavily dependent on the discovery, design and optimisation of the solid electrolytes that they are based on. In recent years, Li- and Na-rich anti-perovskite solid electrolytes have risen to become highly promising candidate materials for solid-state batteries on the basis of their high ionic conductivity, wide electrochemical window, stability, low cost and structural diversity. This perspective highlights experimental and atomistic modelling progress currently being made for Li- and Na-rich anti-perovskite solid electrolytes. We focus on several critical areas of interest in these materials, including synthesisability, structure, ion transport mechanisms, anion rotation, interfaces and their compatibility with anti-perovskite cathodes for the possible formation of anti-perovskite electrolyte- and cathode-based solid-state batteries. The opportunities and challenges for the design and utilisation of these materials in state-of-the-art solid-state batteries are also discussed. As featured throughout this perspective, the versatility, diversity and performance of anti-perovskite solid electrolytes make them one of the most important materials families currently under consideration for solid-state batteries.

Ionic liquids (ILs) have been labeled as a promising green alternative to traditional materials; however, many ILs have been discovered to be toxic, especially hydrophobic ILs (HILs). HILs are limited in their structural diversity as most are composed of heteroaromatic cations with long alkyl chains and paired with [BF4], [PF6], or [NTf2] anions. This study aims to diversify HILs by synthesizing two sets of HILs with unique cations and anions. The first set of HILs contain cholinium- and dicholinium-based cations paired with the [NTf2] anion. The [DC-ether] cation is identified as a promising cation and is paired with an array of asymmetric bis(sulfonyl)amide anions to form the second set of HILs. In total, twenty HILs are synthesized. Each HIL is characterized using traditional physicochemical techniques and is evaluted for toxicity using in vitro and in vivo methods.

Na-ion batteries (NIBs) are promising alternatives to Li-ion batteries (LIBs) due to the low cost, abundance, and high sustainability of sodium resources. However, the high performance of inorganic electrode materials in LIBs does not extend to NIBs because of the larger ion size of Na+ than Li+ and more complicated electrochemistry. Therefore, it is vital to search for high-performance electrode materials for NIBs. Organic electrode materials (OEMs) with the advantages of high structural tunability and abundant structural diversity show great promise in developing high-performance NIBs. To achieve advanced OEMs for NIBs, a fundamental understanding of the structure–performance correlation is desired for rational structure design and performance optimization. In this review, recent advances in developing OEMs for non-aqueous, aqueous, and all-solid-state NIBs are presented. The challenges, advantages, mechanisms, development, and applications of advanced OEMs in NIBs are also discussed. Perspectives for the innovation of structure design principle and future research direction of OEMs in non-aqueous, aqueous, and all-solid-state NIBs are provided.

Marine sponge-associated fungi are promising sources of structurally interesting and bioactive secondary metabolites. Great plenty of natural products have been discovered from spongeassociated fungi in recent years. Here reviewed are 571 new compounds isolated from marine fungi associated with sponges in 2010-2018. These molecules comprised eight different structural classes, including alkaloids, polyketides, terpenoids, meroterpenoids, etc. Moreover, most of these compounds demonstrated profoundly biological activities, such as antimicrobial, antiviral, cytotoxic, etc. This review systematically summarized the structural diversity, biological function, and future potential of these novel bioactive natural products for drug discovery.

Insects build myriad structures out of diverse materials. These structures serve purposes that range from facilitating prey capture to housing their entire colony. Whereas some insects operate solitarily, others collectively build large and complex structures. The architecture of these structures vis-a-vis their ultimate function poses fascinating questions that require multidisciplinary investigations. Importantly, because the underlying design and architectural principles have evolved over millions of years to withstand multitude of environmental perturbations, they offer important lessons for human-made structures. The vast variety of insect-built structures reflects how diverse insects have adapted to resolve the ecological challenges in their specific habitats. Here, we survey insect-built structures from a comparative perspective to ask what design and architectural principles can be gleaned from them. We discuss the key hypotheses about building-behaviours, their neural underpinnings, the functional role of insect-built structures and their biomimetic potential.

Assembly of distinct types of species, particularly possessing anisotropic configurations, is the premise to broaden structural diversity and explore materials' collective properties. However, it remains a great challenge to programmably cocrystallize manifold anisotropic nanoparticles with the desired assembly mode, because it requires not only the complementarity of both sizes and shapes but also the control over their directional interactions. Here, by introducing DNA origami technique into lattice engineering, we synthesize two types of DNA nano-objects with different symmetries and program the heterogeneous functional patches precisely on their surfaces with nanometer-level precision, which could guide further assembly of these nano-objects. We show that these anisotropic DNA nano-objects could be cocrystallized along specified modes via modulating the combination of surface patches. The highly ordered DNA crystals were thoroughly evidenced by techniques including small-angle X-ray scattering and electron microscopy after careful encapsulation of a thin layer of silica on these DNA nano-objects. Our strategy endows distinct shapes of organic DNA origami structures with regulation features to control the sophisticated modes of cocrystallization of these diverse components, laying a foundation for designing and fabricating customized three-dimensional structures with given optical and mechanical properties.

Precise control over the monomeric sequence on natural sequence-defined polymers (SDPs) leads to their structural diversity and functions. However, absolute control over the monomeric sequence on a...

Highlights • Definition and pathogenesis of metabolic syndrome is briefly described. • Sesquiterpene lactones isolated from medicinal plants used in traditional medicine. • In vivo and in vitro biological activities of sesquiterpene lactones are considered. • Chemical and biological properties of natural sesquiterpene lactones are documented., Metabolic syndrome comprises a cluster of metabolic disorders related to the development of cardiovascular disease and type 2 diabetes mellitus. In latter years, plant secondary metabolites have become of special interest because of their potential role in preventing and managing metabolic syndrome. Sesquiterpene lactones constitute a large and diverse group of biologically active compounds widely distributed in several medicinal plants used for the treatment of metabolic disorders. The structural diversity and the broad spectrum of biological activities of these compounds drew significant interests in the pharmacological applications. This review describes selected sesquiterpene lactones that have been experimentally validated for their biological activities related to risk factors of metabolic syndrome, together with their mechanisms of action. The potential beneficial effects of sesquiterpene lactones discussed in this review demonstrate that these substances represent remarkable compounds with a diversity of molecular structure and high biological activity, providing new insights into the possible role in metabolic syndrome management.

Structural diversity and phase transition in the field of two-dimensional self-assembly have gained immense attention because of their potential value in nanoscience and nanotechnology. We present ...

Metal-organic framework (MOF) is a powerful material for electrocatalytic applications due to its structural diversity and tunability. Herein, the MOF with an extended organic linker, NiFe(dobpdc), is synthesized and investigated for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). NiFe(dobpdc) features a yarn-ball like structure assembly from 2D nanosheets subunits and high electrocatalytic activity properties. Theoretical calculations suggest the dobpdc4- can extract/release charges in the electrocatalytic reaction of (∗ → OH∗) and (OH∗ → O∗), respectively. This bifunctional NiFe(dobpdc) electrocatalyst significantly elevates electrocatalytic performance with a lowest overpotential of 207 mV@10 mA cm-2 for OER and 113 mV@10 mA cm-2 for HER, meanwhile, the ultralow overpotentials needed to achieve the high current density of 100 mA cm-2 for OER (251 mV) and HER (170 mV). This study provides a promising strategy to design MOF electrocatalysts for electrocatalytic applications.

By using an anion-directed synthesis approach, two new Gd(III)-based coordination polymers (CP) {[Gd2(HL)2(C2O4)(H2O)2] 2H2O}n (1) and [Gd(HL)(SO4)]n (2) have been successfully prepared by hydrothe...

Two new mixed-ligand coordination polymers based on the Ni(II) ion as the metal center [Ni(L1)(DCTP)] n (1, L1 = 1,1′-(1,4-butanediyl)bis-1H-benzimidazole) and [Ni(L2)(DCTP)] n (2, L2 = 1,4-bis(5,6...

Benefiting from high specific capacity, molecular structural diversity, low cost and renewability, widely concerned small organic carbonyl electrode materials have been developed rapidly in recent ...

Summary Porous ladder polymer networks (ladder PPNs) represent an emerging class of porous organic materials constituted by crosslinked, fully fused ladder-type backbones. Their unique structural characteristic allows for the integration of the properties of porous organic polymers and ladder polymers in a synergistic manner, affording materials featuring high porosity, structural diversity, backbone rigidity, extended π-conjugation, extraordinary stability, etc. These materials with various topologies can be bottom-up synthesized by either direct ring-fusing crosslinking or stepwise crosslinking followed by ladderization. These ladder PPNs exhibit the anticipated ultrahigh stability, electrical conductivity, functional rigid pores, or entropically favorable gas adsorption. The synergistic combination of these functions promises the great potential of ladder PPNs in a wide range of future applications, including energy storage, catalysis, and sensing. To achieve these goals, it is critical to address the fundamental and practical challenges associated with the narrow scope of topologies, structural defects, synthetic scalability, and processability of ladder PPNs.

In this work, under hydrothermal conditions, two novel polyoxometalates (POMs)-based CuII and CuI hybrid materials with 2,6-(1,2,4-triazole-4-yl)pyridine (L1), namely yellow block crystals [Cu2(L1)...

In the current investigation, we report five new co-crystals formed by combinations of triphenylphosphine sulfide (PS) with 1,3,5-triiodo-2,4,6-trifluorobenzene (I3F), triphenylphosphine sulfide (P...

Wild Microcystis have highly diverse colonial structures and sizes, including variable colony geometry, cell arrangement, and diameter. These structural and dimensional variations may play an important role in continual, frequent Microcystis blooms during summer and autumn, the cause of which still remains unclear. Here, laboratory cultures and field investigations were applied to assess mechanisms that drive variation in structure and size, as well as factors that influence diversity. The results demonstrated that colonies grew to large sizes at the expense of their structure being loose and inhomogeneous. Furthermore, colonies may spontaneously change structure to relieve the constraints of size in return. Influencing factors (nutrient limits and turbulent shear) tended to promote these variations. Our work highlights that the diversity of Microcystis colonies may be a result of structural variations as survival strategies for gaining a higher upper size limit. Therefore, during seasonal successions, large colonies commonly have porous or loosely arranged structures, such as in M. aeruginosa. Additionally, this study hypothesized three possible transition routes for better understanding structural diversity and variations in Microcystis.

In many regions, forestry practices are shifting to partial harvesting approaches that seek to maintain species and structural diversity in managed forests. We monitored windthrow for 21 years following partial cutting treatments with 0%, 30%, and 60% removal in a large, replicated experiment located in mixed-species mature and old-growth forests of fire origin. There was no evidence that wind damage to merchantable trees (≥17.5 cm) varied among the three removal treatments. We found no evidence of a short-term spike in susceptibility to windthrow after partial cutting during the initial years following treatment. Over 21 years, a total basal area of 2.4 m2·ha–1 was damaged, which was 5.9% of the original standing basal area at the start of the experiment. We found clear differences in susceptibility to windthrow among the different tree species. The percentage of original standing trees that were windthrown varied from 0% to 23.7%. Eight of nine species had ≤10% damage over the monitoring period. Foresters should be aware of differences among tree species in risk of wind damage but should not use a general concern about susceptibility to windthrow as a reason to avoid partial cutting systems (that can achieve a diversity of management objectives) in structurally diverse, multispecies forests.

N-heterocyclic carbenes (NHCs) are highly versatile ligands with unique features that are able to engage into robust metal-ligand bonds, owing to their strong electron sigma-donating and relatively weak pi-accepting abilities. Aiming at efficient and stable emitters, coordination features of NHCs have been successfully employed for modulating both optical and redox properties yielding outstanding Ir(III)complexes. In addition, NHCs are an unparalleled tool that helps to suppressing nonradiative pathways and shift emission into the blue region. As a result, Ir(III)complexes with NHC ligands represent an appealing class of phosphorescent emitters that show great potential application in light-emitting devices, electro-chemiluminescence and biomedicine. Herein, the interplay between structural diversity and photophysical properties will be discussed for a colorful palette of Ir-III-NHC complexes in a systematic approach. Finally, their employment in optoelectronic devices and biomedicine will be described.