Synthesis and Structural Characterization of a Series of Lanthanide(II) Amides: Steric Effect of Amido Ligand

The synthesis and structures of a series of lanthanide(II) and lanthanide(III) complexes supported by the amido ligand N(SiMe3)Ar were described. Several lanthanide(III) amide chlorides were synthesized by a metathesis reaction of LnCl3 with lithium amide, including {[(C6H5)(Me3Si)N]2YbCl(THF)}2·PhCH3 (1), [(C6H3-iPr2-2,6)(SiMe3)N]2YbCl(μ-Cl)Li(THF)3·PhCH3 (4), [(C6H3-iPr2-2,6)(SiMe3)N]YbCl2(THF)3 (6), and [(C6H3-iPr2-2,6)(SiMe3)N]2SmCl3Li2(THF)4 (7). The reduction reaction of 1 with Na−K alloy afforded bisamide ytterbium(II) complex [(C6H5)(Me3Si)N]2Yb(DME)2 (2). The same reaction for Sm gave an insoluble black powder. An analogous samarium(II) complex [(C6H5)(Me3Si)N]2Sm(DME)2 (3) was prepared by the metathesis reaction of SmI2 with NaN(C6H5)(SiMe3). The reduction reaction of ytterbium chloride 4 with Na−K alloy afforded monoamide chloride {[(C6H3-iPr2-2,6)(SiMe3)N]Yb(μ-Cl)(THF)2}2 (5), which is the first example of ytterbium(II) amide chloride, formed via the cleavage of the Yb−N bond. The same reduction reaction of 7 gave a normal bisamide complex [(C6H3-iPr2-2,6)(SiMe3)N]2Sm(THF)2 (8) via Sm−Cl bond cleavage. This is the first example for the steric effect on the outcome of the reduction reaction in lanthanide(II) chemistry. 5 can also be synthesized by the Na/K alloy reduction reaction of 6. All of the complexes were fully characterized including X-ray diffraction for 1−7

sj-pdf-1-jcc-10.1177_00220221241242442 – Supplemental material for Mask On, Barriers Off: How Face Masks Enhance Social Connection and Responsibility in Different Cultural Context

Supplemental material, sj-pdf-1-jcc-10.1177_00220221241242442 for Mask On, Barriers Off: How Face Masks Enhance Social Connection and Responsibility in Different Cultural Context by Taiyang Zhao, Yan Lu, Wei Song, Yingxin Yao and Liying Zhou in Journal of Cross-Cultural Psychology</p

Synthesis and Characterization of a Series of New Lanthanide Derivatives Supported by Silylene-Bridged Diamide Ligands and Their Catalytic Activities for the Polymerization of Methyl Methacrylate

The synthesis and structures of a series of new lanthanide complexes supported by silylene-bridged diamide ligands are described. The complex {[Me2Si(NPh)2]YbCl(TMEDA)}2 (1) can be synthesized by YbCl3 with PhLiNSiMe2NLiPh in 1:1 molar ratio in good yield. Treatment of {[Me2Si(NPh)2]LnCl(THF)n}2 in situ and Cp‘Na in 1:2 molar ratio afforded a series of new anionic complexes:  {[Me2Si(NPh)2]LnCp‘2}{Li(DME)3} [Cp‘ = C5H5, Ln = Yb (2); Sm(3); Cp‘ = MeC5H4, Ln = Yb(4)]. Complexes 2 and 4 can also be synthesized by Cp‘2YbCl with PhLiNSiMe2NLiPh in 1:1 molar ratio in good yield. The complex 1 reacted with PhLiNSiMe2NLiPh in 1:1 molar ratio to yield an anionic amide complex, {[Me2Si(NPh)2]2Yb(THF)2Li(THF) (6). These complexes were characterized by elemental analysis, IR, and 1H NMR. The molecular structures of 2−4 and 6 were further determined by X-ray diffraction techniques. These anionic complexes showed high activity for the polymerization of methyl methacrylate (MMA) at rt, giving syndiotactic-rich polymers with high molecular weights (Mn > 104) and relatively narrow molecular weight distributions (Mw/Mn = 1.54−1.85)

Comparative transcriptome analysis on drought stress-induced floral formation of <i>Curcuma kwangsiensis</i>

The rhizomes and tubers of Curcuma kwangsiensis have extensive medicinal value in China. However, the inflorescences of C. kwangsiensis are rarely known in horticulture, because of its low field flowering rate. In order to improve the flowering rate of C. kwangsiensis, we conducted drought stress treatment on the rhizome of C. kwangsiensis. The flowering rate of rhizome was the highest after 4d of drought stress treatment, and the buds on the rhizome could be obviously swell on the 4th day of rehydration culture. In order to identify the genes regulating the flowering time of Curcuma kwangsiensis, comparative transcriptome analysis was performed on the buds on rhizomes before drought stress treatment, 4 d after drought stress treatment and 4 d after rehydration culture. During this process, a total of 20 DEGs controlling flowering time and 23 DEGs involved in ABA synthesis and signal transduction were identified, which might regulate the flowering of C. kwangsiensis under drought stress. Some floral integration factors, such as SOC1 and FTIP, were up-regulated under drought stress for 4 d, indicating that C. kwangsiensis had flowering trend under drought stress. The results of the present study will provide theoretical support for the application of Curcuma kwangsiensis in gardening.</p

Synthesis and Structural Characterization of a Series of Lanthanide(II) Amides: Steric Effect of Amido Ligand

The synthesis and structures of a series of lanthanide(II) and lanthanide(III) complexes supported by the amido ligand N(SiMe3)Ar were described. Several lanthanide(III) amide chlorides were synthesized by a metathesis reaction of LnCl3 with lithium amide, including {[(C6H5)(Me3Si)N]2YbCl(THF)}2·PhCH3 (1), [(C6H3-iPr2-2,6)(SiMe3)N]2YbCl(μ-Cl)Li(THF)3·PhCH3 (4), [(C6H3-iPr2-2,6)(SiMe3)N]YbCl2(THF)3 (6), and [(C6H3-iPr2-2,6)(SiMe3)N]2SmCl3Li2(THF)4 (7). The reduction reaction of 1 with Na−K alloy afforded bisamide ytterbium(II) complex [(C6H5)(Me3Si)N]2Yb(DME)2 (2). The same reaction for Sm gave an insoluble black powder. An analogous samarium(II) complex [(C6H5)(Me3Si)N]2Sm(DME)2 (3) was prepared by the metathesis reaction of SmI2 with NaN(C6H5)(SiMe3). The reduction reaction of ytterbium chloride 4 with Na−K alloy afforded monoamide chloride {[(C6H3-iPr2-2,6)(SiMe3)N]Yb(μ-Cl)(THF)2}2 (5), which is the first example of ytterbium(II) amide chloride, formed via the cleavage of the Yb−N bond. The same reduction reaction of 7 gave a normal bisamide complex [(C6H3-iPr2-2,6)(SiMe3)N]2Sm(THF)2 (8) via Sm−Cl bond cleavage. This is the first example for the steric effect on the outcome of the reduction reaction in lanthanide(II) chemistry. 5 can also be synthesized by the Na/K alloy reduction reaction of 6. All of the complexes were fully characterized including X-ray diffraction for 1−7

Synthesis and Structural Characterization of a Series of Lanthanide(II) Amides: Steric Effect of Amido Ligand

The synthesis and structures of a series of lanthanide(II) and lanthanide(III) complexes supported by the amido ligand N(SiMe3)Ar were described. Several lanthanide(III) amide chlorides were synthesized by a metathesis reaction of LnCl3 with lithium amide, including {[(C6H5)(Me3Si)N]2YbCl(THF)}2·PhCH3 (1), [(C6H3-iPr2-2,6)(SiMe3)N]2YbCl(μ-Cl)Li(THF)3·PhCH3 (4), [(C6H3-iPr2-2,6)(SiMe3)N]YbCl2(THF)3 (6), and [(C6H3-iPr2-2,6)(SiMe3)N]2SmCl3Li2(THF)4 (7). The reduction reaction of 1 with Na−K alloy afforded bisamide ytterbium(II) complex [(C6H5)(Me3Si)N]2Yb(DME)2 (2). The same reaction for Sm gave an insoluble black powder. An analogous samarium(II) complex [(C6H5)(Me3Si)N]2Sm(DME)2 (3) was prepared by the metathesis reaction of SmI2 with NaN(C6H5)(SiMe3). The reduction reaction of ytterbium chloride 4 with Na−K alloy afforded monoamide chloride {[(C6H3-iPr2-2,6)(SiMe3)N]Yb(μ-Cl)(THF)2}2 (5), which is the first example of ytterbium(II) amide chloride, formed via the cleavage of the Yb−N bond. The same reduction reaction of 7 gave a normal bisamide complex [(C6H3-iPr2-2,6)(SiMe3)N]2Sm(THF)2 (8) via Sm−Cl bond cleavage. This is the first example for the steric effect on the outcome of the reduction reaction in lanthanide(II) chemistry. 5 can also be synthesized by the Na/K alloy reduction reaction of 6. All of the complexes were fully characterized including X-ray diffraction for 1−7

Ytterbium(II) Complex Bearing a Diaminobis(phenolate) Ligand: Synthesis, Structure, and One-Electron-Transfer and ε-Caprolactone Polymerization Reactions

The first divalent ytterbium complex supported by a diaminobis(phenolate) ligand, YbL(THF)2·0.5C7H8 (1; THF = tetrahydrofuran), was synthesized in good yield by the amine elimination reaction of Yb[N(SiMe3)2]2(THF)2 with H2L (L = [Me2NCH2CH2N(CH2-2-OC6H2-3,5-But2)2]) in a 1:1 molar ratio. X-ray structural determination shows complex 1 to be a THF-solvated monomer, which adopts a distorted octahedral coordination geometry around the Yb atom. Complex 1 can react with PhNCO and PhC⋮CH, as a single electron-transfer reagent, to give the corresponding reduction coupling product [(YbLOCNPh)(THF)]2·4THF (2) and the alkynide complex YbLC⋮CPh(DME) (3; DME = 1,2-dimethoxyethane). Complexes 2 and 3 have been characterized by X-ray crystal structural analysis. In complex 2, the dianionic oxamide ligand resulting from the reductive coupling of two phenyl isocyanate molecules coordinates to two Yb atoms in a μ,η4 fashion. Complex 3 has a monomeric structure with a Yb−C(terminal phenylacetynide) bond length of 2.374(3) Å. Complex 1 is also a highly efficient catalyst for ring-opening polymerization of ε-caprolactone

Elucidating phylogenetic relationships within the genus <i>Curcuma</i> through the comprehensive analysis of the chloroplast genome of <i>Curcuma viridiflora</i> Roxb. 1810 (Zingiberaceae)

Curcuma viridiflora Roxb., a plant species of significant pharmaceutical interest, has been the subject of limited chloroplast genomic research. In this study, we present the sequencing and assembly of the C. viridiflora chloroplast genome, which is characterized by a circular chromosome spanning 162,212 base pairs and a GC content of 36.20%. The genome encodes 87 protein-coding genes (PCGs), 38 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes. A phylogenetic analysis was conducted, incorporating eight related species, and based on the complete chloroplast genome and protein-coding DNA sequences of six related taxa within the genus. Outgroup species Zingiber zerumbet and Zingiber officinale were also included in the analysis. The results indicate a close relationship between C. viridiflora and Curcuma phaeocaulis, Curcuma sichuanensis, and Curcuma yunnanensis. This study provides the first chloroplast genome of C. viridiflora, thereby contributing a valuable genomic resource for future research on medicinal plants within the Curcuma genus.</p

Complete mitochondrial genome and phylogenetic analysis of <i>Sineleotris saccharae</i> (Perciformes, Odontobutiae)

The freshwater sleeper, Sineleotris saccharae Herre, 1940 is a member of the Odontobutiae family, widely distributed in southern China. In the present study, we determined the complete mitochondrial genome of S. saccharae for the first time and analyzed its evolutionary relationship. The complete mitochondrial genome of S. saccharae was 16,487 bp long, and had 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), 2 ribosomal RNA (rRNAs) and a control region (CR). The mitogenome of S. saccharae shared the same gene organization and orientation as other teleosts. According to phylogenetic research, S. saccharae was sister to S. chalmersi with high support value, providing the monophyly of the genus Sineleotris. These results will be helpful for understanding the systematics of the odontobutids.</p

Discovery of novel serum metabolic biomarkers in patients with polycystic ovarian syndrome and premature ovarian failure

Several widely recognized metabolites play a role in regulating the pathophysiological processes of various disorders. Nonetheless, the lack of effective biomarkers for the early diagnosis of polycystic ovarian syndrome (PCOS) and premature ovarian failure (POF) has led to the discovery of serum-based metabolic biomarkers for these disorders. We aimed to identify various differentially expressed metabolites (DEMs) through serum-based metabolic profiling in patients with PCOS and POF and in healthy individuals by using liquid chromatography–mass spectrometry analysis. Furthermore, heatmap clustering, correlation, and Z-score analyses were performed to identify the top DEMs. Kyoto Encyclopedia of Genes and Genomes enriched pathways of DEMs were determined using metabolite-based databases. Moreover, the clinical significance of these DEMs was evaluated on the basis of area under the receiver operating characteristic curve. Significantly dysregulated expressions of several metabolites were observed in the intergroup comparisons of the PCOS, POF, and healthy control groups. Furthermore, 6 DEMs were most frequently observed among the three groups. The expressions of these DEMs were not only directly correlated but also exhibited potential significance in patients with PCOS and POF. Novel metabolites with up/downregulated expressions can be discovered in patients with PCOS and POF using serum-based metabolomics; these metabolites show good diagnostic performance and can act as effective biomarkers for the early detection of PCOS and POF. Furthermore, these metabolites might be involved in the pathophysiological mechanisms of PCOS and POF via interplay with corresponding genes.</p