Palladium-catalyzed facile synthesis of furoquinolinones and furopyridinones

<p>This work is focused on the development of a convenient and efficient approach for the synthesis of furoquinolinones and furopyridinones through palladium-catalyzed cyclization reactions between styrenes and 4-hydroxyquinolinones/4-hydroxypyridinones under air conditions. Studies conducted to evaluate the antitumoral potential of the resulted compounds revealed that some of the obtained furoquinolinones exhibited <i>in vitro</i> antiproliferative activity on human-derived stomach cancer cell lines.</p

Facile Synthesis and Functionality-Dependent Electrochemistry of Fe-Only Hydrogenase Mimics

A series of azadithiolate (adt)-bridged Fe-only hydrogenase model complexes, Fe2(CO)6(μ-adt)C6H4I-4 (1), Fe2(CO)6(μ-adt)C6H4CCR [R = C6H4NO2-4 (2), C6H4CHO-4 (3), C6H4NH2-4 (4), C6H4COOH-4 (5), C6H4COOCH2CH3-4 (6), C6H4F-4 (7), C6H5 (8), C6H4OCH3-4 (9), C6H4N(CH3)2-4 (10)], [Fe2(CO)5(PPh3)(μ-adt)C6H4I-4 (11), and Fe2(CO)5(PPh3)(μ-adt)C6H4CCC6H4NO2-4 (12), have been synthesized in high yields under mild conditions. The linear geometry and rigidity of a triple bond act as an effective bridge to anchor a functionality ranging from electron-donating to electron-accepting, even coordinative groups in the adt model complexes. X-ray crystal analysis of 2, 3, and 6−12 reveals that the model complexes retain the butterfly structure of Fe2S2 model analogues. A rigid phenylacetylene offers excellent control over the distance between the functional group and the active site of Fe2S2 model complexes. The unusual Fe−Fe distance and the angles found in the molecular packing of 6 are originated from the intriguing intermolecular C−H···O and C−H···S interactions. More importantly, electrochemical studies reveal that all of the complexes can catalyze electrochemical reduction of protons to molecular hydrogen, but the reduction potential for the electron-transfer step can be remarkably altered by the functionality R. The electroreductively active nitro group in 2 and 12 displays the enhanced current at a potential substantially less negative than the reduction of [FeIFeI] + e− → [FeIFe0], which is most accessible and becomes the initial step. For complex 3, the second reduction peak for the electron-transfer step involves the contribution from the aldehyde functionality. As the electroreductively inactive groups are incorporated, the reduction process of [FeIFeI] + e− → [FeIFe0] appears first and the second reduction peak for the electron-transfer step from the [FeIFe0] + e− → [Fe0Fe0] process for 4−10 is clearly observed. Therefore, the order of electron and proton uptake is closely related to the electroreductively active functionality, R. Varying the nature of the functionality R leads to the electron-transfer step changes from the reduction of the electroreductively active R group to the active site of Fe2S2 model complexes subsequently. Accordingly, notwithstanding, acetic acid is too weak to protonate the series of 2−12, different reduction pathways can be followed, and the electrochemically catalyzed behavior may occur at different reduction levels

Facile Synthesis and Functionality-Dependent Electrochemistry of Fe-Only Hydrogenase Mimics

A series of azadithiolate (adt)-bridged Fe-only hydrogenase model complexes, Fe2(CO)6(μ-adt)C6H4I-4 (1), Fe2(CO)6(μ-adt)C6H4CCR [R = C6H4NO2-4 (2), C6H4CHO-4 (3), C6H4NH2-4 (4), C6H4COOH-4 (5), C6H4COOCH2CH3-4 (6), C6H4F-4 (7), C6H5 (8), C6H4OCH3-4 (9), C6H4N(CH3)2-4 (10)], [Fe2(CO)5(PPh3)(μ-adt)C6H4I-4 (11), and Fe2(CO)5(PPh3)(μ-adt)C6H4CCC6H4NO2-4 (12), have been synthesized in high yields under mild conditions. The linear geometry and rigidity of a triple bond act as an effective bridge to anchor a functionality ranging from electron-donating to electron-accepting, even coordinative groups in the adt model complexes. X-ray crystal analysis of 2, 3, and 6−12 reveals that the model complexes retain the butterfly structure of Fe2S2 model analogues. A rigid phenylacetylene offers excellent control over the distance between the functional group and the active site of Fe2S2 model complexes. The unusual Fe−Fe distance and the angles found in the molecular packing of 6 are originated from the intriguing intermolecular C−H···O and C−H···S interactions. More importantly, electrochemical studies reveal that all of the complexes can catalyze electrochemical reduction of protons to molecular hydrogen, but the reduction potential for the electron-transfer step can be remarkably altered by the functionality R. The electroreductively active nitro group in 2 and 12 displays the enhanced current at a potential substantially less negative than the reduction of [FeIFeI] + e− → [FeIFe0], which is most accessible and becomes the initial step. For complex 3, the second reduction peak for the electron-transfer step involves the contribution from the aldehyde functionality. As the electroreductively inactive groups are incorporated, the reduction process of [FeIFeI] + e− → [FeIFe0] appears first and the second reduction peak for the electron-transfer step from the [FeIFe0] + e− → [Fe0Fe0] process for 4−10 is clearly observed. Therefore, the order of electron and proton uptake is closely related to the electroreductively active functionality, R. Varying the nature of the functionality R leads to the electron-transfer step changes from the reduction of the electroreductively active R group to the active site of Fe2S2 model complexes subsequently. Accordingly, notwithstanding, acetic acid is too weak to protonate the series of 2−12, different reduction pathways can be followed, and the electrochemically catalyzed behavior may occur at different reduction levels

Photocatalytic Hydrogen Evolution from Rhenium(I) Complexes to [FeFe] Hydrogenase Mimics in Aqueous SDS Micellar Systems: A Biomimetic Pathway

To offer an intriguing access to photocatalytic H2 generation in an aqueous solution, the hydrophobic photosensitizer, Re(I)(4,4′-dimethylbpy)(CO)3Br (1) or Re(I)(1,10-phenanthroline)(CO)3Br (2), and [FeFe] H2ases mimics, [Fe2(CO)6(μ-adt)CH2C6H5] (3) or [Fe2(CO)6(μ-adt)C6H5] (4) [μ-adt = N(CH2S)2], have been successfully incorporated into an aqueous sodium dodecyl sulfate (SDS) micelle solution, in which ascorbic acid (H2A) was used as a sacrificial electron donor and proton source. Studies on the reaction efficiency for H2 generation reveal that both the close contact and the driving force for electron transfer from the excited Re(I) complexes and [FeFe] H2ases mimics are crucial for efficient H2 generation with visible light irradiation. Steady-state and time-resolved investigations demonstrate that the electron transfer takes place from the excited Re(I) complex 1 or 2 to [FeFe] H2ases mimic catalyst 3, leading to the formation of the long-lived Fe(I)Fe(0) charge-separated state that can react with a proton to generate Fe(I)Fe(II)·H, an intermediate for H2 production. As a result, a reaction vessel for the photocatalytic H2 production in an aqueous solution is established

Breast cancer-associated SNP rs72755295 is a cis-regulatory variation for human EXO1

Abstract Breast cancer is the most common malignant tumor in women. A previous genome-wide association study reports that rs72755295, a SNP locating at intron of EXO1 (exonuclease 1), is associated with breast cancer. Due to the complete linkage disequilibrium between rs72755295 and rs4149909, a nonsynonymous mutation for EXO1, rs4149909 is supposed to be the causal SNP. Since EXO1 is overexpressed in breast carcinoma samples, we hypothesized that the genetic variations in this locus might confer breast cancer risk by regulating EXO1 expression. To substantiate this, a functional genomics study was performed. The dual luciferase assay indicated that G of rs72755295 presents significantly higher relative enhancer activity than A, thus verifying that this SNP can influence gene expression in breast cell. Through chromosome conformation capture it was disclosed that the enhancer containing rs72755295 can interact with the EXO1 promoter. RNA-seq analysis indicated that EXO1 expression is dependent on the rs72755295 genotype. By chromatin immunoprecipitation, the transcription factor PAX6 (paired box 6) was recognized to bind the region spanning rs72755295. In electrophoretic mobility shift assay, G of rs72755295 displays obviously higher binding affinity with nuclear protein than A. Our results indicated that rs72755295 is a cis-regulatory variation for EXO1 and might confer breast cancer risk besides rs4149909.</div

Structure and Photoluminescence Tuning Features of Mn²⁺- and Ln³⁺-Activated Zn-Based Heterometal–Organic Frameworks (MOFs) with a Single 5-Methylisophthalic Acid Ligand

In attempts to investigate whether the photoluminescence properties of the Zn-based heterometal–organic frameworks (MOFs) could be tuned by doping different Ln3+ (Ln = Sm, Eu, Tb) and Mn2+ ions, seven novel 3D homo- and hetero-MOFs with a rich variety of network topologies, namely, [Zn(mip)]n (Zn–Zn), [Zn2Mn(OH)2(mip)2]n (Zn–Mn), [Mn2Mn(OH)2(mip)2]n (Mn–Mn), [ZnSm(OH)(mip)2]n (Zn–Sm), [ZnEu(OH)(mip)2]n (Zn–Eu1), [Zn5Eu(OH)(H2O)3(mip)6·(H2O)]n (Zn–Eu2), and [Zn5Tb(OH)(H2O)3(mip)6]n (Zn–Tb), (mip = 5-methylisophthalate dianion), have been synthesized hydrothermally based on a single 5-methylisophthalic acid ligand. All compounds are fully structurally characterized by elemental analysis, FT-IR spectroscopy, TG-DTA analysis, single-crystal X-ray diffraction, and X-ray powder diffraction (XRPD) techniques. The various connectivity modes of the mip linkers generate four types of different structures. Type I (Zn–Zn) is a 3D homo-MOF with helical channels composed of Zn2(COO)4 SBUs (second building units). Type II (Zn–Mn and Mn–Mn) displays a nest-like 3D homo- or hetero-MOF featuring window-shaped helical channels composed of Zn4Mn2(OH)4(COO)8 or Mn4Mn2(OH)4(COO)8 SBUs. Type III (Zn–Sm and Zn–Eu1) presents a complicated corbeil-like 3D hetero-MOF with irregular helical channels composed of (SmZnO)2(COO)8 or (EuZnO)2(COO)8 heterometallic SBUs. Type IV (Zn–Eu2 and Zn–Tb) contains a heterometallic SBU Zn5Eu(OH)(COO)12 or Zn5Tb(OH)(COO)12, which results in a 3D hetero-MOF featuring irregular channels impregnated by parts of the free and coordinated water molecules. Photoluminescence properties indicate that all of the compounds exhibit photoluminescence in the solid state at room temperature. Compared with a broad emission band at ca. 475 nm (λex = 380 nm) for Zn–Zn, compound Zn–Mn exhibits a remarkably intense emission band centered at 737 nm (λex = 320 nm) due to the characteristic emission of Mn2+. In addition, the fluorescence intensity of compound Zn–Mn is stronger than that of Mn–Mn as a result of Zn2+ behaving as an activator for the Mn2+ emission. Compound Zn–Sm displays a typical Sm3+ emission spectrum, and the peak at 596 nm is the strongest one (λex = 310 nm). Both Zn–Eu1 and Zn–Eu2 give the characteristic emission transitions of the Eu3+ ions (λex = 310 nm). Thanks to the ambient different crystal-field strengths, crystal field symmetries, and coordinated bonds of the Eu3+ ions in compounds Zn–Eu1 and Zn–Eu2, the spectrum of the former compound is dominated by the 5D0 → 7F2 transition (612 nm), while the emission of the 5D0 → 7F4 transition (699 nm) for the latter one is the most intense. Compound Zn–Tb emits the characteristic Tb3+ ion spectrum dominated by the 5D4 → 7F5 (544 nm) transition. Upon addition of the different activated ions, the luminescence lifetimes of the compounds are also changed from the nanosecond (Zn–Zn) to the microsecond (Zn–Mn, Mn–Mn, and Zn–Sm) and millisecond (Zn–Eu1, Zn–Eu2, and Zn–Tb) magnitude orders. The structure and photoluminescent property correlations suggest that the presence of Mn2+ and Ln3+ ions can activate the Zn-based hetero-MOFs to emit the tunable photoluminescence

Structure and Photoluminescence Tuning Features of Mn²⁺- and Ln³⁺-Activated Zn-Based Heterometal–Organic Frameworks (MOFs) with a Single 5-Methylisophthalic Acid Ligand

In attempts to investigate whether the photoluminescence properties of the Zn-based heterometal–organic frameworks (MOFs) could be tuned by doping different Ln3+ (Ln = Sm, Eu, Tb) and Mn2+ ions, seven novel 3D homo- and hetero-MOFs with a rich variety of network topologies, namely, [Zn(mip)]n (Zn–Zn), [Zn2Mn(OH)2(mip)2]n (Zn–Mn), [Mn2Mn(OH)2(mip)2]n (Mn–Mn), [ZnSm(OH)(mip)2]n (Zn–Sm), [ZnEu(OH)(mip)2]n (Zn–Eu1), [Zn5Eu(OH)(H2O)3(mip)6·(H2O)]n (Zn–Eu2), and [Zn5Tb(OH)(H2O)3(mip)6]n (Zn–Tb), (mip = 5-methylisophthalate dianion), have been synthesized hydrothermally based on a single 5-methylisophthalic acid ligand. All compounds are fully structurally characterized by elemental analysis, FT-IR spectroscopy, TG-DTA analysis, single-crystal X-ray diffraction, and X-ray powder diffraction (XRPD) techniques. The various connectivity modes of the mip linkers generate four types of different structures. Type I (Zn–Zn) is a 3D homo-MOF with helical channels composed of Zn2(COO)4 SBUs (second building units). Type II (Zn–Mn and Mn–Mn) displays a nest-like 3D homo- or hetero-MOF featuring window-shaped helical channels composed of Zn4Mn2(OH)4(COO)8 or Mn4Mn2(OH)4(COO)8 SBUs. Type III (Zn–Sm and Zn–Eu1) presents a complicated corbeil-like 3D hetero-MOF with irregular helical channels composed of (SmZnO)2(COO)8 or (EuZnO)2(COO)8 heterometallic SBUs. Type IV (Zn–Eu2 and Zn–Tb) contains a heterometallic SBU Zn5Eu(OH)(COO)12 or Zn5Tb(OH)(COO)12, which results in a 3D hetero-MOF featuring irregular channels impregnated by parts of the free and coordinated water molecules. Photoluminescence properties indicate that all of the compounds exhibit photoluminescence in the solid state at room temperature. Compared with a broad emission band at ca. 475 nm (λex = 380 nm) for Zn–Zn, compound Zn–Mn exhibits a remarkably intense emission band centered at 737 nm (λex = 320 nm) due to the characteristic emission of Mn2+. In addition, the fluorescence intensity of compound Zn–Mn is stronger than that of Mn–Mn as a result of Zn2+ behaving as an activator for the Mn2+ emission. Compound Zn–Sm displays a typical Sm3+ emission spectrum, and the peak at 596 nm is the strongest one (λex = 310 nm). Both Zn–Eu1 and Zn–Eu2 give the characteristic emission transitions of the Eu3+ ions (λex = 310 nm). Thanks to the ambient different crystal-field strengths, crystal field symmetries, and coordinated bonds of the Eu3+ ions in compounds Zn–Eu1 and Zn–Eu2, the spectrum of the former compound is dominated by the 5D0 → 7F2 transition (612 nm), while the emission of the 5D0 → 7F4 transition (699 nm) for the latter one is the most intense. Compound Zn–Tb emits the characteristic Tb3+ ion spectrum dominated by the 5D4 → 7F5 (544 nm) transition. Upon addition of the different activated ions, the luminescence lifetimes of the compounds are also changed from the nanosecond (Zn–Zn) to the microsecond (Zn–Mn, Mn–Mn, and Zn–Sm) and millisecond (Zn–Eu1, Zn–Eu2, and Zn–Tb) magnitude orders. The structure and photoluminescent property correlations suggest that the presence of Mn2+ and Ln3+ ions can activate the Zn-based hetero-MOFs to emit the tunable photoluminescence

DataSheet_1_Niche divergence at the intraspecific level in an endemic rare peony (Paeonia rockii): A phylogenetic, climatic and environmental survey.zip

Ecological factors have received increasing attention as drivers of speciation but also in the maintenance of postspeciation divergence. However, the relative significance of the responses of species to climate oscillations for driving niche divergence or conservatism in the evolution of many species that pass through diverse environments and limited geographical boundaries remains poorly understood. Paeonia rockii (one of the ancient species of Paeonia) comprising two subspecies called Paeonia rockii subsp. rockii and Paeonia rockii subsp. taibaishanica is an endemic, rare, and endangered medicinal plant in China. In this study, we integrated whole chloroplast genomes, and ecological factors to obtain insights into ecological speciation and species divergence in this endemic rare peony. RAxML analysis indicated that the topological trees recovered from three different data sets were identical, where P. rockii subsp. rockii and P. rockii subsp. taibaishanica clustered together, and molecular dating analyses suggested that the two subspecies diverged 0.83 million years ago. In addition, ecological niche modeling showed that the predicted suitable distribution areas for P. rockii subsp. rockii and P. rockii subsp. taibaishanica differed considerably, although the predicted core distribution areas were similar, where the population contracted in the last interglacial and expanded in the last glacial maximum. Under the emissions scenarios for the 2050s and 2070s, the suitable distribution areas were predicted to contract significantly, where the migration routes of the two subspecies tended to migrate toward high latitudes and elevations, thereby suggesting strong responses of the distributions of the two subspecies to climate change. These findings combined with the phylogeographic relationships provide comprehensive insights into niche variation and differentiation in this endemic rare peony, and they highlight the importance of geological and climatic changes for species divergence and changes in the population geographic patterns of rare and endangered medicinal plants in East Asia.</p

Thin Copper-Based Film for Efficient Electrochemical Hydrogen Production from Neutral Aqueous Solutions

Here, we report a water-soluble copper­(II) complex acting as a hydrogen evolution catalyst in a neutral aqueous solution, which could be further developed to form water reduction material through electrodeposition. The material with extremely low loading of 33 μg Cu cm^–2 showed impressive TON value of 5876 and TOF of 734 h^–1 in 8 h CPE experiment in a neutral phosphate buffer solution. In X-ray photoelectron spectroscopy (XPS), the high-resolution C 1s peak is corresponding to a CC bond at 284.8 eV, C–N bond at 285.6 eV, C–O bond at 286.4 eV, and two different types of nitrogen configurations at around 398.5 and 399.9 eV are ascribed to pyridinic CN and tertiary amine C–N bonds, respectively, which implies that the ligand might be incorporated into the copper active material. It is assumed that the presence of the ligand has an influence on the activity and stability of the deposit

Table8_A Chromosome-Level Genome Assembly of Yellowtail Kingfish (Seriola lalandi).XLSX

Yellowtail kingfish (Seriola lalandi) is a pelagic marine piscivore with a circumglobal distribution. It is particularly suitable for open ocean aquaculture owing to its large body size, fast swimming, rapid growth, and high economic value. A high-precision genome is of great significance for future genetic breeding research and large-scale aquaculture in the open ocean. PacBio, Illumina, and Hi-C data were combined to assemble chromosome-level reference genome with the size of 648.34 Mb (contig N50: 28.52 Mb). 175 contigs was anchored onto 24 chromosomes with lengths ranging from 12.28 to 34.59 Mb, and 99.79% of the whole genome sequence was covered. The BUSCOs of genome and gene were 94.20 and 95.70%, respectively. Gene families associated with adaptive behaviors, such as olfactory receptors and HSP70 gene families, expanded in the genome of S. lalandi. An analysis of selection pressure revealed 652 fast-evolving genes, among which mkxb, popdc2, dlx6, and ifitm5 may be related to rapid growth traits. The data generated in this study provide a valuable resource for understanding the genetic basis of S. lalandi traits.</p