Pan-cancer analysis of NUP155 and validation of its role in breast cancer cell proliferation, migration, and apoptosis.

NUP155 is reported to be correlated with tumor development. However, the role of NUP155 in tumor physiology and the tumor immune microenvironment (TIME) has not been previously examined. This study comprehensively investigated the expression, immunological function, and prognostic significance of NUP155 in different cancer types. Bioinformatics analysis revealed that NUP155 was upregulated in 26 types of cancer. Additionally, NUP155 upregulation was strongly correlated with advanced pathological or clinical stages and poor prognosis in several cancers. Furthermore, NUP155 was significantly and positively correlated with DNA methylation, tumor mutational burden, microsatellite instability, and stemness score in most cancers. Additionally, NUP155 was also found to be involved in TIME and closely associated with tumor infiltrating immune cells and immunoregulation-related genes. Functional enrichment analysis revealed a strong correlation between NUP155 and immunomodulatory pathways, especially antigen processing and presentation. The role of NUP155 in breast cancer has not been examined. This study, for the first time, demonstrated that NUP155 was upregulated in breast invasive carcinoma (BRCA) cells and revealed its oncogenic role in BRCA using molecular biology experiments. Thus, our study highlights the potential value of NUP155 as a biomarker in the assessment of prognostic prediction, tumor microenvironment and immunotherapeutic response in pan-cancer.

Exfoliation of Metal-Organic Frameworks to Give 2D MOF Nanosheets for the Electrocatalytic Oxygen Evolution Reaction.

The structure and properties of materials are determined by a diverse range of chemical bond formation and breaking mechanisms, which greatly motivates the development of selectively controlling the chemical bonds in order to achieve materials with specific characteristics. Here, an orientational intervening bond-breaking strategy is demonstrated for synthesizing ultrathin metal-organic framework (MOF) nanosheets through balancing the process of thermal decomposition and liquid nitrogen exfoliation. In such approach, proper thermal treatment can weaken the interlayer bond while maintaining the stability of the intralayer bond in the layered MOFs. And the following liquid nitrogen treatment results in significant deformation and stress in the layered MOFs' structure due to the instant temperature drop and drastic expansion of liquid N2, leading to the curling, detachment, and separation of the MOF layers. The produced MOF nanosheets with five cycles of treatment are primarily composed of nanosheets that are less than 10 nm in thickness. The MOF nanosheets exhibit enhanced catalytic performance in oxygen evolution reactions owing to the ultrathin thickness without capping agents which provide improved charge transfer efficiency and dense exposed active sites. This strategy underscores the significance of orientational intervention in chemical bonds to engineer innovative materials.

Optical microscopic study on a novel morphological classification method of multiple diagnostic features of Sarcoptes scabiei var. hominis.

Optical microscopy is the gold standard technique used to confirm the diagnosis of scabies. Multiple diagnostic features of the pathogen Sarcoptes scabiei var. hominis (S. scabiei) can be identified under a microscope and classified into 3 categories: mites, eggs and fecal pellets. However, mite and eggshell fragments can also be observed, which have been ignored in the 2020 International Alliance for the Control of Scabies (IACS) Criteria and by most researchers. In this study, we propose a novel morphological classification method that classifies multiple diagnostic features into 5 categories and 7 subcategories. Our results revealed that 65.2% (1893 of 2896) of the positive cases were confirmed through the identification of mites, eggs or fecal pellets, whereas up to 34.6% (1003 of 2896) of the positive cases were confirmed through the identification of mite or eggshell fragments. Therefore, the important diagnostic values of mite and eggshell fragments should be emphasized. Importantly, for the first time, mite and eggshell fragments were classified into 7 subcategories, some of which are easily ignored or confused with contaminating artefacts. We believe that this novel morphological classification method will be beneficial for operator training in interpreting slides and in improving the 2020 IACS Criteria.

Depression score mediate the association between a body shape index and infertility in overweight and obesity females, NHANES 2013-2018.

BACKGROUND: Overweight and obese females demonstrate a significantly increased risk of anovulatory infertility. This study aims to investigate whether depression score could mediate the association between a body shape index (ABSI) and infertility, especially in overweight and obese population. METHODS: We included 5431 adult female Americans from the National Health and Nutrition Examination Survey (NHANES, 2013-2018) database. ABSI manifested the body shape using waist circumference, weight, and height. Infertility or fertility status was defined by interviewing female participants aged ≥ 18 through the reproductive health questionnaires. Depression symptoms were assessed using the Patient Health Questionnaire-9 (PHQ-9) with total scores between 0 and 27. To investigate the association of infertility with ABSI and other individual components, survey-weighted multivariable logistic regression was performed. Mediation analysis of PHQ-9 score was conducted to disentangle the pathways that link ABSI to infertility among the NHANES participants. RESULTS: 596 (10.97%) females were categorized with having infertility among 5431 participants. Participants with infertility showed higher ABSI and PHQ-9 score, appearing greater population proportion with depression symptoms. In the multivariable logistic regression model, ABSI (adjusted odds ratio = 0.14, 95% CI: 0.04 to 0.50) and PHQ-9 (adjusted odds ratio = 1.04, 95% CI: 1.01 to 1.07) were positively associated with infertility. PHQ-9 score was estimated to mediate 0.2% (P = 0.03) of the link between ABSI and infertility in all individuals, but to mediate 13.5% (P < 0.01) of the ABSI-infertility association in overweight and obese adult females. CONCLUSION: The association between ABSI and infertility seems to be mediated by depression symptoms scored by PHQ-9, especially in those adult females with overweigh and obesity. Future studies should be implemented to further explore this mediator in ABSI-infertility link.

EZH2 regulates pancreatic cancer cells through E2F1, GLI1, CDK3, and Mcm4.

Pancreatic cancer (PC) is one of the most common malignant tumors in digestive tract. To explore the role of epigenetic factor EZH2 in the malignant proliferation of PC, so as to provide effective medical help in PC. Sixty paraffin sections of PC were collected and the expression of EZH2 in PC tissues was detected by immunohistochemical assay. Three normal pancreas tissue samples were used as controls. The regulation of EZH2 gene on proliferation and migration of normal pancreatic cell and PC cell were determined by MTS, colony forming, Ki-67 antibody, scratch and Transwell assays. Through differential gene annotation and differential gene signaling pathway analysis, differentially expressed genes related to cell proliferation were selected and verified by RT-qPCR. EZH2 is mainly expressed in the nuclei of pancreatic tumor cells, but not in normal pancreatic cells. The results of cell function experiments showed that EZH2 overexpression could enhance the proliferation and migration ability of PC cell BXPC-3. Cell proliferation ability increased by 38% compared to the control group. EZH2 knockdown resulted in reduced proliferation and migration ability of cells. Compared with control, proliferation ability of cells reduced by 16%-40%. The results of bioinformatics analysis of transcriptome data and RT-qPCR demonstrated that EZH2 could regulate the expression of E2F1, GLI1, CDK3 and Mcm4 in normal and PC cells. The results revealed that EZH2 might regulate the proliferation of normal pancreatic cell and PC cell through E2F1, GLI1, CDK3 and Mcm4.

Discovery of novel potent PI3K/mTOR dual-target inhibitors based on scaffold hopping: Design, synthesis, and antiproliferative activity.

The PI3K/AKT/mTOR pathway is one of the most common dysregulated signaling cascade responses in human cancers, playing a crucial role in cell proliferation and angiogenesis. Therefore, the development of anticancer drugs targeting the PI3K and mTOR pathways has become a research hotspot in cancer treatment. In this study, the PI3K selective inhibitor GDC-0941 was selected as a lead compound, and 28 thiophenyl-triazine derivatives with aromatic urea structures were synthesized based on scaffold hopping, serving as a novel class of PI3K/mTOR dual inhibitors. The most promising compound Y-2 was obtained through antiproliferative activity evaluation, kinase inhibition, and toxicity assays. The results showed that Y-2 demonstrated potential inhibitory effects on both PI3K kinase and mTOR kinase, with IC50 values of 171.4 and 10.2 nM, respectively. The inhibitory effect of Y-2 on mTOR kinase was 52 times greater than that of the positive drug GDC-0941. Subsequently, the antitumor activity of Y-2 was verified through pharmacological experiments such as AO staining, cell apoptosis, scratch assays, and cell colony formation. The antitumor mechanism of Y-2 was further investigated through JC-1 experiments, real-time quantitative PCR, and Western blot analysis. Based on the above experiments, Y-2 can be identified as a potent PI3K/mTOR dual inhibitor for cancer treatment.

Molecular mechanisms and differences in lynch syndrome developing into colorectal cancer and endometrial cancer based on gene expression, methylation, and mutation analysis.

PURPOSE: The aim of this study was to screen biomarkers specific to Lynch syndrome (LS) with colorectal cancer (CRC) or endometrial cancer (EC) to explore the mechanisms by which LS develops into CRC and EC and their differences. METHODS: Differentially expressed or differentially methylated genes and differential mutations were identified in 10 LS, 50 CRC, and 50 EC patients from TCGA, and genes overlapping between LS and CRC or EC (named SGs-LCs and SGs-LEs, respectively) were identified. Afterward, we annotated the enriched GO terms and pathways and constructed a protein-protein interaction (PPI) network. Finally, samples from 10 clinical cases with MSI-H/MSS CRC and EC were collected to verify the mutations and their correlations with five LS pathogenic genes in the SGs-LCs and SGs-LEs. RESULTS: A total of 494 SGs-LCs and 104 SGs-LEs were identified and enriched in 106 and 14 GO terms, respectively. There were great differences in the gene count and enriched terms between SGs-LCs and SGs-LEs. In the PPI network, SST, GCG, SNAP25, and NPY had the highest degree of connection among the SGs-LCs, and KIF20A and NUF2 had the highest degree of connection among the SGs-LE. In the SGs-LCs and SGs-LEs, the genes whose expression levels affected the survival of LS, CRC or EC patients were quite different. CONCLUSIONS: COL11A1 was found to be mutated in MSS CRC patients, similar to the mutations of MSH6. SST, GCG, SNAP25, and NPY may be biomarkers for the development of LS into CRC, and KIF20A and NUF2 may be markers of LS developing into EC.

Highly enantioselective one-pot sequential synthesis of valerolactones and pyrazolones bearing all-carbon quaternary stereocentres.

Highly enantiopure and bioactive δ-valerolactones and pyrazolones, bearing α-all-carbon quaternary stereocentres, were successfully and sequentially prepared via a one-pot procedure starting from readily available, inexpensive materials, catalysed by a new chiral squaramide under mild reaction conditions. An organocatalytic Michael reaction afforded the valerolactones, while a one-pot Michael-hydrazinolysis-imidization cascade yielded the pyrazolones. This procedure is economically efficient and environmentally benign.

Enhancing the tumor cell selectivity of a rhodamine-decorated iridium(III) complex by conjugating with indomethacin for COX-2 targeted photodynamic therapy.

A rhodamine-iridium (III) complex bearing indomethacin moiety, named IM-rho-Ir, was synthesized and evaluated for COX-2 targetable photodynamic therapy. By integrating COX-2 directing group, IM-rho-Ir exhibited enhanced cellular uptake in cancer cells than in normal cells compared to rhodamine-iridium (III) complex without indomethacin moiety.

Point Chirality Controlled Diastereoselective Self-Assembly and Circularly Polarized Luminescence in Quadruple-Stranded Europium(III) Helicates.

Aromatic ß-diketones have been extensively employed as highly effective sensitizers in luminescent lanthanide complexes. However, the difficulties to make the chiral modified groups effectively participate in the frontier molecular orbital (FMO) distributions limit their applications on lanthanide circularly polarized luminescence (CPL) fields. Considering the inherent chirality of the helical structure, a pair of enantiopure dinuclear europium quadruple-stranded helicates, ΔΔ/ΛΛ-(HNEt3)2(Eu2L4) (ΔΔ/ΛΛ)-1; L = R/S-1,2-bis(4,4'-bis(4,4,4-trifluoro-1,3-dioxobutyl)phenoxyl)propane are assembled via a point chirality induced strategy. The comprehensive spectral characteristics combined with density functional theory (DFT) calculations demonstrate that the one point chirality at the spacer of the ligand successfully controls the Δ or Λ configuration around the Eu(III) ion center and the P or M helical patterns of the helicates. The mirror-image CPL and CD spectra further confirm the formation of the enantiomer pairs. As expected, the helicate presents a higher luminescence quantum yield (QY) of 68% and a large |glum| value (0.146). This study effectively combines the excellent sensitization capability of ß-diketone and the helical chirality of helicates. This strategy provides an effective path for the synthesis of lanthanide material with excellent CPL performance.

Metal-Organic Frameworks as Metal Ion Precursors for the Synthesis of Nanocomposites for Lithium-Ion Batteries.

Metal-organic frameworks (MOFs) are promising materials with fascinating properties. Their widespread applications are sometimes hindered by the intrinsic instability of frameworks. However, this instability of MOFs can also be exploited for useful purposes. Herein, we report the use of MOFs as metal ion precursors for constructing functional nanocomposites by utilizing the instability of MOFs. The heterogeneous growth process of nanostructures on substrates involves the release of metal ions, nucleation on substrates, and formation of a covering structure. Specifically, the synthesized CoS with carbon nanotubes as substrates display enhanced performance in a lithium-ion battery. Such strategy not only presents a new way for exploiting the instability of MOFs but also supplies a prospect for designing versatile functional nanocomposites.

A Highly Luminescent Chiral Tetrahedral Eu4L4(L')4 Cage: Chirality Induction, Chirality Memory, and Circularly Polarized Luminescence.

Chiral lanthanide cages with circularly polarized luminescence (CPL) properties have found potential application in enantioselective guest recognition and sensing. However, it still remains a big challenge to develop a simple and robust method for the diastereoselective assembly of homochiral lanthanide cages in view of the large lability of the Ln(III) ions. Herein, we report the first example of the formation of a enantiopure lanthanide tetrahedral cage via a chiral ancillary ligand induction strategy. One such cage, (Eu4L4)(R/S-BINAPO)4, is assembled by four achiral C3-symmeric tris(ß-diketones) (4,4',4″-tris(4,4,4-trifluoro-1,3-dioxobutyl)triphenylamine, L) as faces, four Eu(III) ions as vertices and four chiral R-/S-bis(diphenylphosphoryl)-1,1'-binaphthyl (R/S-BINAPO) as ancillary ligands. X-ray crystallography and NMR and CD spectra confirm the formation of a pair of enantiopure chiral topological tetrahedral cages, (Eu4L4)(R-BINAPO)4 and (Eu4L4)(S-BINAPO)4 (ΔΔΔΔ-1 and ΛΛΛΛ-1). As expected, the tetrahedral cages present strong CPL with |glum| values up to 0.20, while they unexpectedly give ultrahigh luminescent quantum yields (QYs) of up to 81%, the highest value reported in chiral Ln(III) complexes. More impressively, the chiral memory effect for a lanthanide-based assembly is observed for the first time. The chirality of the original cage 1 framework is retained after R/S-BINAPO is replaced by the achiral bis[2-(diphenylphosphino)phenyl] ether oxide (DPEPO), and thus another pair of enantiopure Eu(III) tetrahedral cages, ΔΔΔΔ- and ΛΛΛΛ-[(Eu4L4)(DPEPO)4] (ΔΔΔΔ-2 and ΛΛΛΛ-2), have been isolated. Encouragingly, cage 2 also presents an impressive luminescence quantum yield (QY = 68%) and intense CPL (|glum| = 0.11). This study offers a simple and low-cost synthesis strategy for the preparation of lanthanide cages with CPL properties.

An Easily Available Ratiometric Reaction-Based AIE Probe for Carbon Monoxide Light-up Imaging.

Carbon monoxide (CO) is a significant gasotransmitter that naturally modulates inflammatory responses. Visualization of CO in situ would help to reveal its physiological/pathological functions. Unfortunately, most existing CO fluorescent probes show aggregation-caused quenching (ACQ) properties. Herein, we report the reaction-based fluorescent probe (BTCV-CO) with aggregation-induced emission (AIE) characteristics for CO detection and imaging. This ratiometric AIE probe showed excellent stability, high sensitivity (detection limit of 30.8 nM), and superior selectivity. More importantly, this CO-responsive AIE probe could be facilely designed and easily obtained by two-step synthesis with high yield, providing an easy-to-handle AIE toolbox for real-time visualization of CO in a living system.

Exploiting the application of l-aptamer with excellent stability: an efficient sensing platform for malachite green in fish samples.

Effective monitoring of the content of malachite green (MG) in aquaculture is of great importance for food safety. Traditional methods for MG assay, such as chromatography and spectroscopy, have been criticized for expensive instrumentation and complicated pretreatments. An MG RNA aptamer (MGA) is a powerful tool for immediate and rapid detection of MG. However, RNA is easily degraded by nucleases and is unstable in the environment, making accurate and reliable detection of MG difficult. In order to address the problems, an innovative levo (l)-MGA with excellent stability is designed to perform the specific recognition function. Interestingly, the gel electrophoresis and fluorescence measurement results indicate that this unnaturally occurring l-aptamer is resistant to nuclease degradation and it can be kept intact in the standard buffer solution under room temperature for quite a long time. A label-free, simple, and efficient method has been developed for sensitive detection of MG in fish tissue, which holds promising potential in food analysis and environmental monitoring.

Hepatitis B Virus-Encoded MicroRNA Controls Viral Replication.

MicroRNAs (miRNAs) are a class of small, single-stranded, noncoding, functional RNAs. Hepatitis B virus (HBV) is an enveloped DNA virus with virions and subviral forms of particles that lack a core. It was not known whether HBV encodes miRNAs. Here, we identified an HBV-encoded miRNA (called HBV-miR-3) by deep sequencing and Northern blotting. HBV-miR-3 is located at nucleotides (nt) 373 to 393 of the HBV genome and was generated from 3.5-kb, 2.4-kb, and 2.1-kb HBV in a classic miRNA biogenesis (Drosha-Dicer-dependent) manner. HBV-miR-3 was highly expressed in hepatoma cell lines with an integrated HBV genome and HBV+ hepatoma tumors. In patients with HBV infection, HBV-miR-3 was released into the circulation by exosomes and HBV virions, and HBV-miR-3 expression had a positive correlation with HBV titers in the sera of patients in the acute phase of HBV infection. More interestingly, we found that HBV-miR-3 represses HBsAg, HBeAg, and replication of HBV. HBV-miR-3 targets the unique site of the HBV 3.5-kb transcript to specifically reduce HBc protein expression, levels of pregenomic RNA (pgRNA), and HBV replication intermediate (HBV-RI) generation but does not affect the HBV DNA polymerase level, thus suppressing HBV virion production (replication). This may explain the low levels of HBV virion generation with abundant subviral particles lacking core during HBV replication, which may contribute to the development of persistent infection in patients. Taken together, our findings shed light on novel mechanisms by which HBV-encoded miRNA controls the process of self-replication by regulating HBV transcript during infection.IMPORTANCE Hepatitis B is a liver infection caused by the hepatitis B virus (HBV) that can become a long-term, chronic infection and lead to cirrhosis or liver cancer. HBV is a small DNA virus that belongs to the hepadnavirus family, with virions and subviral forms of particles that lack a core. MicroRNA (miRNA), a small (∼22-nt) noncoding RNA, was recently found to be an important regulator of gene expression. We found that HBV encodes miRNA (HBV-miR-3). More importantly, we revealed that HBV-miR-3 targets its transcripts to attenuate HBV replication. This may contribute to explaining how HBV infection leads to mild damage in liver cells and the subsequent establishment/maintenance of persistent infection. Our findings highlight a mechanism by which HBV-encoded miRNA controls the process of self-replication by regulating the virus itself during infection and might provide new biomarkers for diagnosis and treatment of hepatitis B.

Chiral BINAPO-Controlled Diastereoselective Self-Assembly and Circularly Polarized Luminescence in Triple-Stranded Europium(III) Podates.

Chiral lanthanide helical architectures have received intense attentions in recent years because of their potential applications as chiral probes and sensors and as circularly polarized luminescence (CPL) materials. However, stereoselectivity control in the self-assembly of lanthanide helicate is challenging due to the poor stereochemical preference and variable coordination numbers of Ln(III) ions. Herein, we reported the employing chiral ancillary ligand R/S-BINAPO to induce achiral tripodal ligand to form a pair of homochiral lanthanide triple-helical podates [Eu(TTEA)((R/S)-BINAPO); R/S-1] {(R/S)-BINAPO = ( R/ S)-2,2'-bis(diphenylphosphoryl)-1,1'-binaphthyl; TTEA = tris[(4-(4,4,4-trifluoro-1,3-dioxobutyl)-benzamido)ethyl]amine}. X-ray crystallographic analysis for rac-1 reveals that the chirality of BINAPO is transferred during the self-assembly process to give either P or M helical architectures in podates. The 1H and 31P NMR and circular dichroism measurements confirm the diastereopurity of the assemblies in solution. A detailed optical and chiroptical characterization reveals that the luminescent enantiopure podates not only exhibit intense CPL with | glum| values reaching 0.072 but also show high luminescence quantum yields of 32.8%. Our results provide a feasible strategy for designing homochiral helical lanthanide supramolecular architecture and synthesizing excellent CPL materials.

Modulation of the Coordination Environment around the Magnetic Easy Axis Leads to Significant Magnetic Relaxations in a Series of 3d-4f Schiff Complexes.

A series of Salen-type Zn(II)-Dy(III) complexes [L1Zn(II)ClDy(III)(acac)2]·H2O (1), [L1Zn(II)BrDy(III)(acac)2]·H2O (2), [L1Zn(II)(H2O)Dy(III)(acac)2]·CH2Cl2·PF6 (3), [L2Zn(II)(H2O)Dy(III)(acac)2]·PF6 (4), and Co(III)-Dy(III) complexes [L1Co(III)Br2Dy(III)(acac)2]·CH2Cl2 (5), [L2Co(III)Cl2Dy(III)(acac)Cl(MeO)] (6), [L2Co(III)Cl2Dy(III)(acac)Cl(H2O)] (7), and [L2Co(III)Cl2Dy(III)(NO3)2(MeO)] (8) heterobinuclear single-molecule magnets (SMMs) were synthesized and magnetically characterized. These complexes were constructed by incorporating diamagnetic Zn(II) and Co(III) ions with acetylacetone (acac) and compartmental Schiff-base ligands (H2L1 = N, N'-bis(2-oxy-3-methoxybenzylidene)-1,2-phenylenediamine; H2L2 = N, N'-bis(2-oxy-3-methoxybenzylidene)-1,2-diaminocyclohexane). In the Zn(II)-Dy(III) (1-4) system, the coordination environments of the Dy(III) ions are nearly identical, but the apical coordination atom to the Zn(II) ion is different. Complexes 1, 2, and 4 displayed no magnetic relaxation in the absence of external magnetic field, but complex 3 displayed more pronounced SMM behavior with a relaxation energy barrier Ueff/ kB 38 K and magnetic hysteresis at 1.8 K. The SMM performances of 5, 6, and 7 were enhanced significantly by incorporating an octahedral Co(III) instead of square-pyramidal Zn(II) and replacing one of acac- group around Dy(III) ion by a neutral O atom, displaying Ueff of 167, 118, and 75 K as well as magnetic hysteresis up to 3.5 K. These studies indicated that the remote diamagnetic Zn(II) and Co(III) ions played a key role, and the SMM properties were very strongly related to the special coordination atoms configuration around Dy(III) ion. When this coordination configuration around was broken as 8 exhibited, however, it resulted in a dramatically decreased SMM performance. From this work, the key factors that significantly affect the SMM performance of these heteronuclear Zn(II)/Co(III)-Dy(III) SMMs are unambiguously presented.

Metal-Organic Framework Wears a Protective Cover for Improved Stability.

Metal-organic frameworks (MOFs) with an ordered channel and porosity show great promise for a myriad of purposes. Unfortunately, the coordination bond of metal ions and organic ligands easily weakens in unfavorable environments, which poses a key problem in expanding the application of MOFs. Herein, we report a general and efficient strategy to enhance the stability and preserve the porosity of MOFs by coating them with reduced graphene oxide (rGO). The prepared hybrid material consisted of MOFs and rGO, as the core and the protective shell, respectively. It is worth noting that the obtained MOFs@rGO composite material maintained a well-defined crystal structure and showed good catalytic activity as well as enhanced stability. Notably, this novel and general method of coating MOFs with a thin protective rGO shell will broaden the application fields of MOFs and open up a new avenue for the research of MOFs.

Isopropylmagnesium chloride-promoted unilateral addition of Grignard reagents to ß-diketones: one-pot syntheses of ß-tertiary hydroxyl ketones or 3-substituted cyclic-2-enones.

The regioselective unilateral additions of Grignard reagents to acyclic or cyclic ß-diketones were effectively promoted by sub-stoichiometric amounts of i-PrMgCl to afford ß-tertiary hydroxyl ketones or 3-substituted cyclic-2-enones, respectively. Also, the addition of Grignard reagents to acyclic ß-diketones followed by a reaction with cyclic ß-diketones in a one-pot process was put forward. The reaction mechanism was discussed in detail to explain the high regioselectivity via chemical experiments, hydrogen-deuterium exchange and mass spectrometry.

Structural effects on the photophysical properties of mono-ß-diketonate and bis-ß-diketonate Eu(III) complexes.

Two ligands, mono-ß-diketone (p-methoxylbenzoyl)trifluoroacetone (MBTF) and bis-ß-diketone 1,2-bis(4,4'-bis(4,4,4-trifluoro-1,3-dioxobutyl))phenoxyl ethane (BTPE) with similar chemical structures, have been designed and prepared for the purpose of building the relationship between the structures and luminescence properties of Eu(iii) complexes. Structures of the Eu(iii) complexes [Eu(MBTF)3(DMSO)(H2O)] and [Eu2(BTPE)3(DMSO)4] have been defined by single crystal X-ray crystallography. The mono-ß-diketone complex [Eu(MBTF)3(DMSO)(H2O)] is a mononuclear structure, the central Eu(iii) ion is coordinated by eight oxygen atoms from three ligands and two solvents, in a distorted trigonal-dodecahedral (8-TDH) geometry. Whereas, the bis-ß-diketone complex [Eu2(BTPE)3(DMSO)4] adopts a triple-stranded dinuclear structure in which the two Eu(iii) ions are helically wrapped by three bis-bidentate ligands, and each Eu(iii) ion is eight-coordinated by six oxygen atoms from the ligands and two oxygen atoms from the coordinated DMSO molecules, in a distorted square-antiprismatic (8-SAP) geometry. The photophysical properties related to the electronic transition are characterized by the absorbance spectra, the emission spectra, the emission quantum yields, the emission lifetimes, and the radiative (kr) and nonradiative rate constants (knr). The mono-ß-diketone complex [Eu(MBTF)3(DMSO)(H2O)] offers a relatively high emission quantum yield (38%, in solid) compared to that observed in the bis-ß-diketone complex [Eu2(BTPE)3(DMSO)4] (25%, in solid). This enhancement of emission quantum yield in the mono-ß-diketone complex can be attributed to its lower site symmetry around the Eu(iii) ion, lower non-radiative rate constant and higher energy transfer efficiency from the ligand to the metal ion.