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As the well known biodiversity hotspot of the alpine plants in the world (Sun et al., 2017), many studies have been conducted on evolutionary origin and ecological adaptation of those species occurring in the QTP (e.g., Wen et al., 2014, 2019; Zhang et al., 2019). The Qinghai-Tibet Plateau (QTP) comprises a platform (sometimes called the Qinghai-Tibet Plateau I sensu stricto i ), the Himalayas, and Hengduan Mountains (Liang et al., 2018; Mao et al., 2021). Tong et al. (2021) reviewed the reproductive strategies of animal-pollinated alpine plants on the QTP, involving pollination system, pollen limitation, self-pollination, and sexual system. Paleobotany for Ancient Flora of the QTP and Related Paleo-Altitude Paleontology provides direct evidence for ancient flora of the QTP and further evolution in both floral composition and altitude change with time. [Extracted from the article]

2‐Bromobenzoic acids underwent an α‐arylation with cyclohexane‐1,3‐diones to give 1H‐benzo[c]chromene‐1,6(2H)‐diones under Ar atmosphere catalyzed by CuI/l‐proline in the presence of Cs2CO3. The subsequent regioselective oxidation took place under O2 balloon automatically based on the substituents for the construction of structurally diversified benzo[c]coumarin derivatives. [ABSTRACT FROM AUTHOR]

A silver‐induced cycloaddition of isocyanides with acyl chlorides has been developed. This transition metal‐catalyzed strategy provides an effective and scalable approach for the formation of 2,5‐disubstituted oxazoles in good to high yields. The employed silver‐based MOF catalyst can be efficiently recycled without compromising the yield. [ABSTRACT FROM AUTHOR]

The selective modification of α-amino acids and peptides constitutes a pivotal arena for accessing new peptide-based materials and therapeutics. In recent years, visible light photoredox catalysis has appeared as a powerful platform for the activation of small molecules via single-electron transfer events, allowing previously inaccessible reaction pathways to be explored. This review outlines the recent advances, mechanistic underpinnings, and opportunities of applying photoredox catalysis to the expansion of the synthetic repertoire for the modification of specific amino acid residues. 1 Introduction 2 Visible-Light-Mediated Functionalization of α-Amino Acids 2.1 Decarboxylative Functionalization Involving Redox-Active Esters 2.2 Direct Decarboxylative Coupling Strategies 2.3 Hypervalent Iodine Reagents 2.4 Dual Photoredox and Transition-Metal Catalysis 2.5 Amination and Deamination Strategies 3 Photoinduced Peptide Diversification 3.1 Gese-Type Bioconjugation Methods 3.2 Peptide Macrocyclization through Photoredox Catalysis 3.3 Biomolecule Conjugation through Arylation 3.4 C–H Functionalization Manifolds 4 Conclusions and Outlook [ABSTRACT FROM AUTHOR]

A silver‐catalyzed cycloaromatization of 1‐(2‐ethynyl‐phenyl)‐prop‐2‐yn‐1‐ol with isocyanides efficiently provides benzo[b]fluorene and benzofuran‐pyrrole derivatives through a modular cascade reaction that includes a nucleophilic attack on the diyne substrate. A C−C cross‐coupling/oxygen transportation/Diels‐Alder/hydrogen shift/isomerization cascade mechanistic pathway is proposed. [ABSTRACT FROM AUTHOR]

The α‐arylation between cyanoacetate and 2‐(2‐bromophenyl)‐1H‐perimidine took place first catalyzed by CuI/L‐proline in the presence of NaHCO3, and then the amino on perimidine chemoselectively attacked the cyano group to undergo a nucleophilic addition, giving a series of 13‐aminoisoquinolino[2,1‐a]perimidine‐12‐carboxylate derivatives in good yields. [ABSTRACT FROM AUTHOR]

A one-pot procedure for the synthesis of 5-benzoyl-8 H -phthalazino[1,2- b ]quinazolin-8-ones is achieved by an iodine-catalyzed reaction of 2-aminobenzohydrazides and 2-alkynylbenzaldehydes in good yields. The salient feature of this strategy is a domino type process including a condensation, addition, hydroamination, and a noteworthy benzyl automatic oxidation by oxygen under metal-catalyst-free conditions. [ABSTRACT FROM AUTHOR]

Abstract: CuI accompanyied by Cs2CO3 and TBAB was confirmed to be an efficient catalyst combination to promote an Ullmann coupling reaction. It facilitated 2-bromobenzamides to undergo a coupling reaction for the synthesis of symmetrical biaryldiamides in moderate yields at 120 °C under Pd-free conditions.Graphical Abstract: [ABSTRACT FROM AUTHOR]

The chemo‐selective reaction of 2‐amino‐N′‐arylbenzohydrazide and ketonic acid catalyzed by iodine was used to synthesize various 2,3‐dihydroquinazolin‐4(1H)‐ones efficiently. The use of levulinic acid furnished a series of 2,3,3a,4‐tetrahydropyrrolo[1,2‐a]quinazoline‐1,5‐diones in high yields, while acetobutyric acid only afforded the quinazoline skeletons without forming the second pyridine ring. Using alcohol as the solvent instead of ionic liquids, a subsequent esterification was performed with the carboxylic group of acetobutyric acid substrate in one‐pot manner. [ABSTRACT FROM AUTHOR]

Both hybridization and intraspecific morphological variation across environmental gradients complicate species delineation. We aimed to discern both possibilities that may blur species boundaries in the Carpinus viminea–Carpinus laxiflora–Carpinus londoniana species complex. We conducted statistical analyses on 535 specimens encompassing the entire distribution of this species complex to identify phenotypic clusters. Additionally, we analyzed genetic divergence and probable hybridization between clusters using 76 individuals from 37 populations. Based on phenotypic and genetic clusters, we tentatively recognized four species: C. viminea, C. fargesii, C. laxiflora, and C. londoniana. Except for rare overlapping distributions between C. fargesii and C. londoniana, the redefined four species are mostly allopatric to each another based on their distributions. The morphological delimitation, species boundary and distribution of each species differ distinctly from past taxonomic treatments. For example, specimens previously identified under C. viminea, in fact, belong to three different species. Hybrids between C. fargesii and C. londoniana exhibit morphological traits similar to C. viminea, thereby contributing to difficulties in determining species boundaries and outlining species distributions. These findings suggest that local selection and geographical isolation may together have promoted both phenotypic and genetic divergences within this species complex. However, interspecific hybridization blurs species boundaries by producing hybrids with phenotypic similarity in addition to intraspecific variation. This study emphasizes the importance of statistical analyses of population‐level morphological and genetic variations across major distributional ranges for an integrative delimitation of species boundaries and the identification of hybridization and hybrids. [ABSTRACT FROM AUTHOR]

At 60 °C in DMSO, the iodine-catalyzed reaction of 3-aminopyrazine-2-carbohydrazide and 2-(arylethynyl)benzaldehydes led hydrazones. Increasing the reaction temperature to 100 °C, the amino and amido still indicated inactive, only the imine took part in the addition of acetylene bond to give 2-arylisoquinolines in high yields with the cleavage of N-N bond unexpectedly under metal-free conditions. [ABSTRACT FROM AUTHOR]

The iodine-catalyzed reaction of 2-amino- N′-arylbenzohydrazides and haloketones was carried out in ionic liquids and was found in good chemoselectivity. 5-Chloropentan-2-one selectively gave fused pyrrolo[1,2- a]quinazolin-5(1 H)-one derivatives, and 6-chlorohexan-2-one only formed simple quinazolin-4(1 H)-ones, while the second cyclization did not take place at all. Graphical Abstract: [ABSTRACT FROM AUTHOR]

2-(1 H-benzo[ d]imidazol-2-yl)anilines reacted with haloketones including 5-chloropentan-2-one and 6-chlorohexan-2-one catalyzed by iodine, giving benzo[4,5]imidazo[1,2- c]pyrrolo[1,2- a]quinazoline and 6 H-benzo[4,5]imidazo[1,2- c]pyrido[1,2- a]quinazoline derivatives, respectively. This domino-type reaction formed two new heterocycles and three new covalent bonds in one-pot procedure and provided a green method for the synthesis of fused pentacyclic heterocycles bearing both quinazoline and benzimidazole moieties in ionic liquids. [ABSTRACT FROM AUTHOR]

The Sonogashira reaction first, and then intra-molecular hydroamination of alkyne catalyzed by CuI/ o -phen was proved to be an efficient method for the synthesis of imidazo[2,1- a ]isoquinoline, phenanthro[9′,10′:4,5]imidazo[2,1- a ]isoquinoline and acenaphtho[1′,2′:4,5]imidazo [2,1- a ]isoquinoline derivatives in the presence of Cs 2 CO 3 . [ABSTRACT FROM AUTHOR]

A consecutive Sonogashira coupling reaction, acetylene hydroamination cyclization of 2-(2-bromophenyl)quinazolin-4(3H)-ones and terminal alkynes, is described catalyzed by CuI/l-proline in the presence of Cs2CO3. This procedure provided a facile method for the synthesis of isoindolo[1,2-b]quinazolin-10(12H)-one derivatives in good yields. [ABSTRACT FROM AUTHOR]

Mass transfer experiments were carried out in an annular pulsed disc-and-doughnut column (APDDC) using 30% (v/v) TBP-kerosene + uranium nitrate + nitric acid + water system (uranium nitrate system) for both extraction and stripping processes. Parameters in the axial dispersion model (ADM) and plug-flow model (PFM), namely, the axial dispersion coefficient of the continuous phase and the number of mass transfer units, were regressed by correlating the respective model with the experimental concentration profile. The mass transfer coefficient is calculated, and new correlations are developed to predict the axial mixing coefficient of the continuous phase and the volumetric mass transfer coefficient. The height of a transfer unit is also calculated. The influence of axial mixing on mass transfer performance for the uranium nitrate system is discussed. [ABSTRACT FROM AUTHOR]

The annular pulsed disc-and-doughnut column (APDDC) is an important extraction contactor used in the PUREX process. In this work, hydraulic investigation was carried out in a stainless-steel APDDC, with 30% (v/v) tributyl phosphate (TBP)-kerosene + uranium nitrate + nitric acid + water as the test system. Two operation modes with aqueous phase and organic phase as the continuous fluid were performed separately. The equations, which were previously developed for 30% TBP-kerosene + nitric acid + water system in aqueous phase continuous operation mode, were presently used to predict the holdup, the Sauter drop diameter, the flooding holdup, the flooding throughput, and the operating regimes in both operation modes. Good agreement with the experimental data was observed because the wettability of the dispersed phase on the internals in both the operation modes was similar with that in the aqueous phase continuous operation mode in the previous work. An exception is the flooding properties of the organic continuous operation mode because of a different flooding mechanism. And so new equations were proposed to calculate the flooding properties for the organic continuous operation mode. [ABSTRACT FROM AUTHOR]

Based on the previous work of the hydraulic, axial mixing, and mass-transfer performance of an annular pulsed disc-and-doughnut column (APDDC), the effects of scaling-up on its performance were studied in APDDCs with different annular space widths. The effect of scaling-up on holdup was discussed, and a more universal correlation was established. The effect of scaling-up on the Sauter drop diameter could be expressed by the previous obtained correlation. The effects of scaling-up on both the flooding holdup and throughput were mainly reflected in the correlation of the Sauter drop diameter. The equations of operating regimes were also independent of the scaling-up effect as demonstrated by experimental data. The scaling-up effects on the axial-dispersion coefficient of the continuous phase, the mass-transfer coefficient, and the height of a transfer unit were also discussed. [ABSTRACT FROM PUBLISHER]

The annular pulsed disc-and-doughnut column (APDDC) is an important type of extraction equipment in the PUREX process, which has been used in several commercial reprocessing plants. As there are few mass transfer experimental results reported in the literature, the axial mixing and mass transfer performance of an APDDC was studied for both extraction and stripping processes in the present work. Two parameters in the axial dispersion model (ADM), namely, the axial dispersion coefficient of the continuous phase and the number of mass transfer units, were regressed by correlating ADM with experimental concentration profiles. The influence of flow rate and pulsation intensity on these parameters was also investigated. Models developed for the PDDC were tested for correlation with APDDC experimental data and suitable models and conditions were determined. The height of a mass transfer unit was also calculated, which highlights the impact of axial mixing on mass transfer performance. Moreover, the influence of internal wettability on mass transfer performance was discussed. [ABSTRACT FROM AUTHOR]

The annular pulsed disc-and-doughnut column (APDDC) is an important type of solvent-extraction equipment used in the PUREX process. Though it has been used in several commercial reprocessing plants in the world, there are few research results reported in the literature. In the present work, experiments were carried out in a stainless steel annular pulsed disc-and-doughnut column with aqueous phase and organic phase as the continuous fluid separately. The air-purge method was used to measure parameters including the two-phase densities, column weight, and two-phase interface location, which were fed back to a computer for column control. The holdup and Sauter drop diameter, the latter of which was calculated based on the gravitational settling model, are correlated as functions of the operating conditions (such as pulsation intensity, total flux, and flow ratio). Flooding holdup and throughput were determined experimentally and found in good agreement with those predicted by the model of the Sauter drop diameter. Based on the experimental data, operating regimes are divided referring to existing models. In addition, the effects of internal wettability on the hydraulic characteristics are also discussed. [ABSTRACT FROM AUTHOR]

As the highest and largest plateau in the world, the Qinghai-Tibet Plateau, with its numerous endemic species, is one of the important alpine biodiversity hotspots. Only recently have the evolutionary histories and underlying adaptations of these alpine plants become clear, through research mostly based on testable experiments and analyses. In this issue, we collected a total of 13 papers related to such aims. In addition, we selected a few published papers to highlight the major findings in the recent past. We also outlined the outlook and direction of future research. [ABSTRACT FROM AUTHOR]

Phylogeography has been one major focus of evolutionary biology in recent years, with many important advances in Chinese species. In this issue, we collected 11 phylogeographic studies of plants by Chinese laboratories. We further synthesized the main findings and patterns emerging from these and previous phylogeographic studies in China and asked where phylogeographic research should be directed in the coming years. Numerous examples have shown that phylogeographic patterns in China did not show an expected expansion-contraction pattern at large scale, mirroring the geological records showing that no unified ice sheet had developed in China during the Quaternary Period. Instead, regional expansions and intraspecific divergences are very common in most studied species during the Quaternary oscillations. Different intraspecific lineages or alleles (haplotypes) were detected in multiple localized refugia, from where regional or local expansions are likely to have started. Hybridizations and introgressions are frequent between intraspecific lineages or between different species. We also reviewed computational methods for phylogeographic analyses. Despite the great progress made in recent years, there remains much to discover about the spatial-temporal dimensions and underlying speciation mechanisms of Chinese plants. Phylogeographic studies represent a key knot that connects the genus phylogeny (macroevolution) and speciation and adaptation (microevolution). Therefore, we advocate that: (i) phylogeographic studies of plants in China should be directed to the closely related species or a monophyletic group (for example, a genus or a section) in the coming years; and (ii) population genetic data based on direct sequencing multiple loci, especially those from nuclear genome and statistical tests should be widely adopted and enforced. The recovered intraspecific divergences and phylogeographic patterns of multiple-species may allow us to better understand the high plant diversity in China and set up concrete hypotheses for studying plant speciation and diversification mechanisms in this region. [ABSTRACT FROM AUTHOR]

Abstract: The Ligularia–Cremanthodium–Parasenecio (L–C–P) complex of the Tussilagininae (Asteraceae: Senecioneae) contains more than 200 species that are endemic to the Qinghai-Tibetan Plateau in eastern Asia. These species are morphologically distinct; however, their relationships appear complex. A phylogenetic analysis of members of the complex and selected taxa of the tribe Senecioneae was conducted using chloroplast (ndhF and trnL-F) and nuclear (ITS) sequences. Phylogenetic trees were constructed from individual and combined datasets of the three different sequences. All analyses suggested that Doronicum, a genus that has been included in the Tussilagininae, should be excluded from this subtribe and placed at the base of the tribe Senecioneae. In addition, the Tussilagininae should be broadly circumscribed to include the Tephroseridinae. Within the expanded Tussilagininae containing all 13 genera occurring in eastern Asia, Tussilago and Petasites diverged early as a separate lineage, while the remaining 11 genera comprise an expanded L–C–P complex clade. We suggest that the L–C–P clade, which is largely unresolved, most likely originated as a consequence of an explosive radiation. The few monophyletic subclades identified in the L–C–P clade with robust support further suggest that some genera of Tussilagininae from eastern Asia require generic re-circumscriptions given the occurrence of subclades containing species of the same genus in different parts of the phylogentic tree due to homoplasy of important morphological characters used to delimit them. Molecular-clock analyses suggest that the explosive radiation of the L–C–P complex occurred mostly within the last 20 million years, which falls well within the period of recent major uplifts of the Qinghai-Tibetan Plateau between the early Miocene to the Pleistocene. It is proposed that significant increases in geological and ecological diversity that accompanied such uplifting, most likely promoted rapid and continuous allopatric speciation in small and isolated populations, and allowed fixation or acquisition of similar morphological characters within unrelated lineages. This phenomenon, possibly combined with interspecific diploid hybridization because of secondary sympatry during relatively stable stages between different uplifts, could be a major cause of high species diversity in the Qinghai-Tibetan Plateau and adjacent areas of eastern Asia. [Copyright &y& Elsevier]

The genus Saussurea is distributed mainly in the temperate and subarctic regions of Eurasia and consists of about 300 species classified into six subgenera and 20 sections. Sect. Pseudoeriocoryne in the subgenus Eriocoryne comprises four species, and is delimited mainly by acaulescence and an inflorescence with congested capitula surrounded by a rosette of leaves. All of these species are endemic to the arid Qinghai–Tibet Plateau. Sequences from the chloroplast DNA trnL–F region were obtained for the four species in this section and 26 other species from four subgenera of Saussurea to resolve phylogenetic relationships among these species and to determine whether the shared characters that define sect. Pseudoeriocoryne are synapomorphic or were acquired by convergent evolution. The resulting phylogenies indicated that Saussurea sect. Pseudoeriocoryne as traditionally defined does not constitute a monophyletic group and that each of its species belongs to separate clades. Furthermore, none of these species showed a close relationship with the other species of subgenus Eriocoryne. Our results further indicated that none of the investigated subgenera are monophyletic, and that species from different subgenera clustered together. All these conclusions are provisional and their confirmation would require stronger phylogenetic support. Two possible explanations are suggested for low sequence divergence, poor resolution of internal clades and clustering of species with the rather distinct morphology of Saussurea detected in the present study. The first is rapid radiation and diversification triggered by fast habitat fragmentation due to the recent lifting of the Qinghai–Tibet Plateau and the Quaternary climate oscillations. This could have led to rapid morphological divergence while sequences diverged very little, and also caused the convergent acquisition of similar characteristics in unrelated lineages due to similar selection pressures. The second possible explanation is that both introgressive hybridization and reticulate evolution might have caused the transferring of cpDNA sequences between morphologically dissimilar species, thus leading to homogenization of sequences between lineages. [Copyright &y& Elsevier]

All taxa endemic to the Qinghai-Tibet Plateau are hypothesized to have originated in situ or from immediately adjacent areas because of the relatively recent formation of the plateau since the Pliocene, followed by the large-scaled biota extinction and recession caused by the Quaternary ice sheet. However, identification of specific progenitors remains difficult for some endemics, especially some endemic genera. Nannoglottis, with about eight species endemic to this region, is one such genus. Past taxonomic treatments have suggested its relationships with four different tribes of Asteraceae. We intend to identify the closest relatives of Nannoglottis by evaluating the level of monophyly, tribal delimitation, and systematic position of the genus by using molecular data from ndhF gene, trnL-F, and ITS region sequences. We find that all sampled species of Nannoglottis are a well-defined monophyly. This supports all recent taxonomic treatments of Nannoglottis, in which all sampled species were placed in one broadly re-circumscribed genus. Nannoglottis is most closely related to the Astereae, but stands as an isolated genus as the first diverging lineage of the tribe, without close relatives. A tentative relationship was suggested for Nannoglottis and the next lineage of the tribe was based on the ITS topology, the “basal group,” which consists of seven genera from the Southern Hemisphere. Such a relationship is supported by some commonly shared plesiomorphic morphological characters. Despite the very early divergence of Nannoglottis in the Astereae, the tribe must be regarded to have its origin in Southern Hemisphere rather than in Asia, because based on all morphological, molecular, biogeographical, and fossil data, the Asteraceae and its major lineages (tribes) are supposed to have originated in the former area. Long-distance dispersal using Southeast Asia as a steppingstone from Southern Hemisphere to the Qinghai-Tibet Plateau is the most likely explanation for this unusual biogeographic link of Nannoglottis. The 23–32-million-year divergence time between Nannoglottis and the other Astereae estimated by DNA sequences predated the formation of the plateau. This estimation is further favored by the fossil record of the Asteraceae and the possible time of origin of the Astereae. Nannoglottis seems to have reached the Qinghai-Tibet area in the Oligocene–Eocene and then re-diversified with the uplift of the plateau. The molecular infragenetic phylogeny of the genus identifies two distinct clades, which reject the earlier infrageneric classification based on the arrangement of the involucral bracts and the length of the ligules, but agree well with the habits and ecological preferences of its current species. The “alpine shrub” vs. “coniferous forest” divergence within Nannoglottis was estimated at about 3.4 million years ago when the plateau began its first large-scale uplifting and the coniferous vegetation began to appear. Most of the current species at the “coniferous forest” clade of the genus are estimated to have originated from 1.02 to 1.94 million years ago, when the second and third uprisings of the plateau occurred, the climate oscillated and the habitats were strongly changed. The assumed evolution, speciation diversity, and radiation of Nannoglottis based on molecular phylogeny and divergence times agree well with the known geological and paleobotanical histories of the Qinghai-Tibet Plateau. [Copyright &y& Elsevier]

A new AgOTf‐catalyzed domino reaction of 2‐alkynylbenzaldehyde and 4‐amino‐1‐methyl‐3‐propyl‐1H‐pyrazole‐5‐carboxamide has been reported via a sequential condensation, cyclization, and acetylenic hydroamination process. The developed protocol provides an efficient and modular access to a range of new fused tetracyclic heterocycle 6‐aryl‐9‐methyl‐11‐propyl pyrazolo[4′,3′:4,5]pyrimido[2,1‐a]isoquinolin‐8(9H)‐ones with two new rings in good yields. [ABSTRACT FROM AUTHOR]

Isoindolo[1,2- b ]quinazolines was obtained in high yields from a reaction between 2-(2-aminobenzamido)malonate and 2-bromobenzaldehyde catalyzed by CuI under Pd and ligand-free conditions. • It is an α -arylation catalyzed by CuI under ligand-free conditions. • The three new bonds and two new heterocycle are formed. • It is a tandem cyclization reaction to fused tetracyclic isoindolo[1,2- b ]quinazolines. A tandem cyclization reaction of diethyl 2-(2-aminobenzamido)malonates and 2-bromobenzaldehydes was developed for the synthesis of isoindolo[1,2- b ]quinazoline derivatives. The quinazoline was formed first catalyzed by CuI, followed by a noteworthy α -arylation reaction under Pd and ligand-free conditions in the presence of Cs 2 CO 3. [ABSTRACT FROM AUTHOR]

The benzyl position was found to be automatically oxidized by oxygen in the reaction of 2-(2-bromophenyl)-1 H -imidazole and 1,3-dicarbonyl compounds catalyzed CuI. This domino procedure involved the subsequent α -arylation, deacylation, nucleophilic addition and benzyl automatic oxidation, and provided an efficient method for the synthesis of (benzo)imidazo[2,1- a isoquinolinone derivatives in good yields. The benzyl position was found to be automatically oxidized by oxygen in the reaction of 2-(2-bromophenyl)-1 H -imidazole and 1,3-dicarbonyl compounds catalyzed CuI. This domino procedure involved the subsequent α -arylation, deacylation, nucleophilic addition and benzyl automatic oxidation, and provided an efficient method for the synthesis of (benzo)imidazo[2,1- a isoquinolinone derivatives in good yields. Image 1 • It is an a -arylation and deacylation promoted by a catalyst of CuI without additional ligand. • The benzyl position was found to be automatically oxidized by oxygen. • It is an efficient method to build imidazo[2,1-a]isoquinolinones in good yields. [ABSTRACT FROM AUTHOR]

The Qinghai–Tibet Plateau (QTP) sensu lato (sl) houses an exceptional species diversity in Asia. To develop a comprehensive understanding of species diversity in this fascinating region, we reviewed recent progress from biogeographic, paleogeographic, paleontological and genomic research of both plants and animals in the QTPsl. Numerous studies have been conducted to examine whether the QTPsl uplift triggered the production of rich species diversity there, whether a Quaternary "unified ice sheet" eliminated plants and animals on the central plateau and how high‐altitude species developed the extreme environment adaptations. Major disputes arose about the first issue, mainly from different understanding of the QTP circumscriptions and related uplift, inaccurate dating of molecular phylogenetic trees, and non‐causal correlations between uplift and species diversification. The QTPsl uplift is spatially and temporally heterogeneous, and abundant fossils reported recently similarly support such an asynchronous upheaval model across the entire region. Available phylogeographic studies of alpine plants and animals suggested their glacial refugia in the central QTPsl, rejecting a unified ice sheet during the Last Glacial Maximum. Genomic evidence from a limited number of alpine species has identified numerous candidate genes for high‐altitude adaptation. In the future, more studies should be focused on speciation and adaptation mechanisms of the alpine species in the QTPsl based on the cutting‐edge methods. [ABSTRACT FROM AUTHOR]

TfOH was proved to be an efficient catalyst to promote the intra-molecular cyclization, Diels-Alder reaction, deprotonation and dehydration, and provided a concise synthesis of 10-benzoyl-3,4-dihydroanthracen-1(2H)-ones in good yields from a reaction of 2-(phenylethynyl) benzaldehyde and cyclohexane-1,3-dione. It underwent in high regioselectivity when center asymmetrical 4,4-dimethylcyclohexane-1,3-dione was used as a reactant. TfOH was proved to be an efficient catalyst to promote a reaction of 2-(phenylethynyl) benzaldehyde and cyclohexane-1,3-dione to provide a concise procedure for the synthesis of 10-benzoyl-3,4-dihydroanthracen-1(2H)-ones in good yields. [ABSTRACT FROM AUTHOR]

A series of 15-arylisoquinolino[2′,1′:1,2]imidazo[4,5-f][1,10]phenanthrolines was synthesized by a copper(I)-catalyzed reaction of 2-(2-bromophenyl)-1H-imidazo[4,5-f][1,10] phenanthrolines and terminal alkyne in the presence of Cs2CO3. It was proved to be an efficient method for the synthesis of hexacyclic compounds bearing three kinds of heterocycles which were isoquinoline, imidazole and phenanthroline. 15-Arylisoquinolino[2',1':1,2]imidazo[4,5-f][1,10]phenanthrolines were synthesized by a copper(I)-catalyzed reaction of 2-(2-bromophenyl)-1H-imidazo[4,5-f][1,10]phenanthrolines and terminal alkynes in the presence of Cs2CO3. [ABSTRACT FROM AUTHOR]

An unprecedented copper‐catalyzed heteroaromatization/sulfonyl transfer of propargylic alcohols with isocyanide has been developed. 3‐Sulfonyl benzofurans and indoles were produced under Cu(I) catalysis in good to high yields. The developed catalytic methodology provides controlled, modular, and facile access to sulfonyl benzoheterocycle scaffolds. [ABSTRACT FROM AUTHOR]

The benzo[4,5]imidazo[1,2-a]naphthyridines and benzo[4,5]imidazo[2,1-a]isoq-uino lines were obtained via a one-pot domino reaction of 2-(2-bromophenyl)-1H-benzo[d]imidazoles and cyclic 1,3-dicarbonyl compounds in good yields. This copper-catalyzed procedure provided an efficient method for the synthesis of fused pentacyclic heterocycles containing a α-arylation of carbonyl reaction. [ABSTRACT FROM AUTHOR]

A novel method for the synthesis of dibenzo[b,f]imidazo[1,2‐d][1,4]oxazepine derivatives was described via cascade Csp2N and Csp2O bond constructions. It was a crossed double Ullmann reactions using 4,5‐diaryl‐2‐(2‐hydroxylphenyl)‐1H‐imidazole as the double nucleophilic centers in the presence of Cs2CO3, while 1‐bromo‐2‐iodobenzene was used as a substrate catalyzed by CuI and o‐phenanthroline in good yields. [ABSTRACT FROM AUTHOR]

Using 2-(2-aminophenyl)quinazolin-4(3 H)-one and 2-(2-phenylethynyl)benzaldehyde as the reactants, silver triflate (AgOTf) was proved to be an efficient catalyst to promote not only quinazoline cyclization, but also the intramolecular hydroamination of alkyne for the synthesis of 6-aryl-17 H ,18a H -isoquinolino[2,1- a ]quinazolino[3,2- c ]quinazolin-17-one derivatives in high yields. [ABSTRACT FROM AUTHOR]

A double Ullmann coupling reaction successfully takes place between 4,5-diaryl-2-(2-bromophenyl)-1 H -imidazoles and 2-bromophenols in the presence of Cs2 CO3. This procedure is catalyzed by copper(I) iodide and o -phenanthroline and provides an efficient method for the synthesis of dibenzo[ b , f ]imidazo[1,2- d ][1,4]oxazepine derivatives in good yields. [ABSTRACT FROM AUTHOR]

Many species of the subfamily Polygonoideae are economically important. However, phylogenetic relationships and taxonomic treatments of these species remain disputed. In this study, we used highly orthologous nuclear genes and plastome sequence variation extracted from transcriptomes from 98 species of 26 genera of Polygonaceae mainly from the subfamily Polygonoideae to construct a robust phylogeny. We discerned six successively diverged and well‐defined clades and both nuclear and plastome phylogenies are highly consistent with each other in this subfamily. Phylogenetic relationships between all clades and subclades were well resolved within Polygonoideae. Our analyses revealed that the shrub tribe Atraphaxideae and the herbal genera Polygonum, Persicaria, and Fallopia are polyphyletic. The sampled species of Polygonoideae started to diversify around the Cretaceous/Tertiary boundary (70 Ma) when the global climate exhibited large oscillations. Further origins of more herbal and woody species were found to have clearly increased during later climatic oscillations. We found that woody habits, especially shrubs, originated multiple times from ancestral herbs in this subfamily. Local dry climates may have favored such habit shifts from ancestral herbs. Our results deepen our understanding of evolutionary diversification of Polygonoideae. [ABSTRACT FROM AUTHOR]

A sequential α-arylation of carbonyl reaction and intra-molecular cyclization of 2-(2-bromophenyl)-1 H-benzo[ d]imidazoles with cyclohexane-1,3-diones was described in 1,4-dioxane catalyzed by Cu(I)/ l-proline. It provided an efficient method for the synthesis of benzo[4, 5]imidazo[1,2- f] phenanthridin-4(1 H)-ones with high efficiency in mild conditions. Graphical Abstract: A sequential α-arylation of carbonyl reaction and intra-molecular cyclization of 2-(2-bromophenyl)-1 H-benzo[ d]imidazoles with cyclohexane-1,3-diones was described in 1,4-dioxane catalyzed by Cu(I)/ l-proline. [ABSTRACT FROM AUTHOR]

Two series of furo[3,2- f]quinoline-2-carboxylate were obtained via a three-component reaction of aldehydes, 5-aminobenzofuran-2-carboxylate, and 4-hydroxy-2 H-chromen-2-one or cyclopentane-1,3-dione in DMF under catalyst-free condition in high yields. This one-pot three-component reaction provided an efficient method for the synthesis of fused polycyclic heterocycles for bioactive screening. [ABSTRACT FROM AUTHOR]

Bone marrow transplantation is regarded as the most effective immunotherapy for hematologic cancer, but it generally faces difficulties in matching. Aberrant expression of histone deacetylases (HDACs) is closely related to the occurrence and development of hematological cancer. Recent studies suggested that HDACs might play a critical role in initiating anti-cancer immune response or enhancing anti-cancer immunotherapy. Besides, combining HDAC inhibition and immunotherapy could prevent immunotherapy resistance in some degree and reach an extended treatment window. This review summarized the relationship between HDACs and immune and described the current understanding of HDACs in immunotherapy for hematologic cancer. HDACs may play a critical role in initiating anti-tumor immune response or enhancing anti-cancer immunotherapy. Combining HDACI and immunotherapy can prevent immunotherapy resistance in some degree and reach an extended treatment window. [Display omitted] •Targeting HDACs could initiate anti-tumor immune response in the hematologic cancer. •Targeting HDACs could enhance anti-tumor immunotherapy for hematologic cancer. •Combining HDACIs and immunotherapy could reach an extended treatment window. [ABSTRACT FROM AUTHOR]

Bone marrow transplantation is regarded as the most effective immunotherapy for hematologic cancer, but it generally faces difficulties in matching. Aberrant expression of histone deacetylases (HDACs) is closely related to the occurrence and development of hematological cancer. Recent studies suggested that HDACs might play a critical role in initiating anti-cancer immune response or enhancing anti-cancer immunotherapy. Besides, combining HDAC inhibition and immunotherapy could prevent immunotherapy resistance in some degree and reach an extended treatment window. This review summarized the relationship between HDACs and immune and described the current understanding of HDACs in immunotherapy for hematologic cancer. HDACs may play a critical role in initiating anti-tumor immune response or enhancing anti-cancer immunotherapy. Combining HDACI and immunotherapy can prevent immunotherapy resistance in some degree and reach an extended treatment window. [Display omitted] •Targeting HDACs could initiate anti-tumor immune response in the hematologic cancer. •Targeting HDACs could enhance anti-tumor immunotherapy for hematologic cancer. •Combining HDACIs and immunotherapy could reach an extended treatment window. [ABSTRACT FROM AUTHOR]

Both geographic isolation and polyploidization are assumed to play an important role in driving species diversification. However, this is rarely illustrated through phylogenomic analyses. The genus Eutrema (Brassicaceae), which also includes the salt‐resistant species, are distributed mainly in Asia with extensive species diversification in the Qinghai–Tibet Plateau (QTP) and adjacent regions. In this study, we revealed almost fully resolved backbone relationships of the genus with genome re‐sequencing data for genomes of 168 individuals from 28 species. Phylogenetic analyses of both plastomes and single‐copy nuclear genes from the whole genome recovered six well‐supported clades with almost consistent relationships. The first two clades are mainly distributed in central China and central Asia, while the other four in the QTP and adjacent regions. All of them diversified within 12 million years. Within each clade, we recovered numerous conflicts in the interspecific relationships between nuclear and plastome phylogenies, likely suggesting hybridization and incomplete lineage sorting during species diversification. Our estimation of genome size and comparison of the number of the single‐copy nuclear genes demonstrated frequent occurrences of polyploids in the genus. Except for an establishment of the backbone phylogeny, our phylogenomic analyses suggest that in addition to strong geographic isolation, polyploidization may have played an important role in species diversification of this genus. [ABSTRACT FROM AUTHOR]

The double Ullmann coupling reactions between 4,5-diaryl-2-(2-bromophenyl)- 1 H -imidazole and 7-bromo-1 H -indole/indazole were successfully carried out, being catalyzed by CuI/ o -phen in the presence of K 2 CO 3. This approach provides an effective way for the synthesis of benzo [6,7]imidazo[1',2':4,5] [1,4]diazepino[3,2,1- hi ]indoles/indazoles via a double Ullmann cross-coupling reaction to build two new C sp 2-N bonds. Copper-catalyzed the double Ullmann coupling reactions between 4,5-diaryl-2-(2-bromophenyl)- 1 H -imidazole and 7-bromo-1 H -indole/indazole were developed, providing an effective method for the synthesis of benzo[6,7]imidazo[1′,2':4,5][1,4]diazepino[3,2,1- hi ]indoles/indazoles in good yields. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of next‐generation sequencing technologies allows researchers to address complex problems in species delimitation, especially for non‐model organisms. The taxonomic status of North American Nyssa species has long been debated and remains controversial. To elucidate the genetic structure and phylogenetic relationships of the five currently recognized North American Nyssa species, we conducted whole‐genome sequencing of representative individuals and identified genome‐wide single‐nucleotide polymorphisms (SNPs) by utilizing the recently released chromosome‐level assembly of Nyssa sinensis genome. Population genetic and phylogenetic analyses consistently inferred four well‐supported genetic clusters from our sampled individuals, that is, N. aquatica, N. ogeche, N. sylvatica, and N. biflora–N. ursina. Although the identification of N. biflora and N. ursina is primarily based on the morphological characteristics of leaves and drupes, the present evidence, including our principal components analysis of leaf morphological traits, strongly supports the taxonomic designation of N. biflora and N. ursina as a single species. In addition, these four genetic clusters were grouped into two major clades, that is, clade 1 (N. aquatica and N. ogeche) and clade 2 (N. sylvatica and N. biflora–N. ursina). Despite the fact that no evidence of widespread gene flow was found between these two major clades, our analyses revealed the possibility of introgression from N. sylvatica into N. biflora, albeit at a relatively low frequency. This study demonstrates the use of whole‐genome sequences as a promising avenue for delimiting species boundaries and further advocates for an integrative approach in the assessment of species delimitation. [ABSTRACT FROM AUTHOR]

In order to explore the comprehensive properties of heat convection in H-type finned tubes installed with small rectangular wings or triangular wings as the longitudinal vortex generators, the field synergy principle was adopted in analysis. At the same attack angle, the surface average and volume average synergy angles of the small triangular wings are bigger than those of the small rectangular wings; at the same time, the volume average synergy angles are bigger than the surface average ones. With the increase of the attack angle, both the surface average and volume average synergy angles decrease first but increase later, which reach their minimum values at the 60° attack angle for the rectangular wings but at the 45° attack angle for the triangular wings. At the same inlet velocity, both the surface average and volume average synergy angles of the 45°-attack-angle triangular wings are bigger than those of the 60°-attack-angle rectangular wings. With the increase of the inlet velocity, both the surface average and volume average synergy angles increase for the 60°-attack-angle rectangular wings and the 45°-attack-angle triangular wings as well. [ABSTRACT FROM AUTHOR]

A CuI/L‐proline‐catalyzed reaction of 2‐(2‐bromophenyl)‐4,5‐diaryl‐1H‐imidazole and potassium ethylxanthate unexpectedly gave bis(2‐(4,5‐diaryl‐1H‐imidazol‐2‐yl)phenyl)sulfane derivatives in high yields, rather than 2,3‐diphenyl‐5H‐benzo[e]imidazo[1,2‐c]thiazine‐5‐thione. This cascade procedure provided an efficient method to synthesize diphenylsulfanes using potassium ethylxanthate as a new type of sulfur source via the Csp2S bond Ullmann reaction twice. [ABSTRACT FROM AUTHOR]

Gene duplication plays an important role in plants for diversification and adaptation to new habitats. In this study, we aim to reconstruct the genome‐scale phylogeny and identify large‐scale gene duplication events for the subtribe Gentianinae (Gentianaceae), which is a great symbol of the alpine plants in the Qinghai–Tibet Plateau. We sequenced and assembled 70 transcriptomes from 67 species, representing all six recognized genera in the subtribe Gentianinae plus the closely related outgroups. Using phylogenomic approaches, the backbone relationships of Gentianinae were almost fully resolved with high bootstrap support. Although instances of conflicts were observed between nuclear and plastid phylogenies, six major clades of Gentianinae were consistently recovered in both phylogenies. In addition, we revealed a high occurrence of duplicated genes in our transcriptome assemblies. Using several gene tree reconciliation methods, we collectively identified 10 nodes in the species tree with large concentrations of duplicated genes. Further analysis indicated that many of these duplicated genes likely arose from hybrid polyploidy, which might also account for some of the topological incongruences between nuclear and plastid phylogenies in Gentianinae. [ABSTRACT FROM AUTHOR]

Summary [ABSTRACT FROM AUTHOR]

Recent work has suggested that rates of introgression should be inversely related to levels of gene flow because introgressed populations cannot be ‘rescued’ by intraspecific gene flow if it is too low. Mitochondrial and chloroplast DNA (mtDNA and cpDNA) experience very different levels of gene flow in conifers due to their contrasted maternal and paternal modes of transmission, hence the prediction that mtDNA should introgress more readily than cpDNA in this group. Here, we use sequence data from both mtDNA and cpDNA to test this hypothesis in a group of closely related spruces species, the Picea asperata complex from China. Nine mitochondrial and nine chloroplast haplotypes were recovered from 459 individuals in 46 natural populations belonging to five species of the Picea asperata complex. Low variation was found in the two mtDNA introns along with a high level of differentiation among populations ( GST = 0.90). In contrast, we detected higher variation and lower differentiation among populations at cpDNA markers ( GST = 0.56), a trend shared by most conifer species studied so far. We found that cpDNA variation, although far from being fully diagnostic, is more species-specific than mtDNA variation: four groups of populations were identified using cpDNA markers, all of them related to species or groups of species, whereas for mtDNA, geographical variation prevails over species differentiation. The literature suggests that mtDNA haplotypes are often shared among related conifer species, whereas cpDNA haplotypes are more species-specific. Hence, increased intraspecific gene flow appears to decrease differentiation within species but not among species. [ABSTRACT FROM AUTHOR]

Abstract: The combined occurrence of both herkogamy and dichogamy in a hermaphrodite species has been considered to strongly favour outcrossing. In this study, we investigated in detail the reproductive ecology of Gentiana straminea Maxim. (Gentianaceae), a hermaphrodite perennial endemic to the Qinghai-Tibet Plateau. In a series of observations and experiments over four consecutive years, we examined whether the combination of dichogamy and herkogamy in individual flowers completely prevents geitonogamous pollen transfer in this species. The mode of floral development clearly indicates that autonomous self-pollination is completely avoided through herkogamy and dichogamy in individual flowers. This implication was confirmed by the breeding experiments, since no seed was produced when flowers were isolated. However, this gentian proved to be highly self-compatible when geitonogamous selfing was artificially induced. Many flowers opened simultaneously on individual plants, the ratio of male to female phase flowers was close to 2:1 in each inflorescence at the full anthesis phase, and they were randomly distributed amongst the upper, middle and lower parts of each stem''s inflorescence. On average, Bombus sushikini Skorikov, the most frequent visitor and only legitimate pollinator of G. straminea, visited nearly two flowers per inflorescence, and four flowers per plant. Among the pollinators'' foraging bouts, the proportions of geitonogamous visits to inflorescences or flowers within an individual plant were 29% and 37%, respectively. Therefore, despite the strict dichogamous and herkogamous characteristics of the individual flowers, geitonogamous selfing might still prevail in G. straminea because of the size of its floral displays and the continuous visiting behavior of B. sushkini. [Copyright &y& Elsevier]