Showing papers in "Zeitschrift für Naturforschung B in 2015"
TL;DR: In this paper, equiatomic CeTX intermetallics with the hexagonal ZrNiAl type structure are formed with electron-rich transition metals (T) and X = Mg, Zn, Cd, Al, Ga, In, Tl, Sn, and Pb.
Abstract: Equiatomic CeTX intermetallics with the hexagonal ZrNiAl type structure are formed with electron-rich transition metals (T) and X = Mg, Zn, Cd, Al, Ga, In, Tl, Sn, and Pb. Their crystal chemistry, chemical bonding, magnetic and electrical properties, and formation of solid solutions are reviewed. The results of 119Sn Mossbauer spectroscopy, high-pressure studies, and hydrogenation reactions are presented.
64 citations
TL;DR: In this paper, two new complexes, [Ni(pydc)(H2O)3] (1) and [Ni (cma)(H 2O) 3] (2), have been synthesized and structurally characterized.
Abstract: Abstract Two new complexes, [Ni(pydc)(H2O)3] (1) and [Ni(cma)(H2O)3] (2) (H2pydc = pyridine-2,6-dicarboxylic acid, H2cma = 2-(carboxymethoxy)benzoic acid), have been synthesized and structurally characterized. In both compounds, NiII is surrounded by one tridentate chelate dianionic ligand (pydc2ˉ for 1 and cma2ˉ for 2) and three coordinated water molecules in a distorted octahedral geometry (NiNO5 for 1 and NiO6 for 2). The magnetic properties for 1 and 2 have been discussed in detail.
25 citations
TL;DR: In this article, a series of novel pyrazoles containing benzofuran and trifluoromethyl moieties were synthesized via two routes starting from 5-(3-(trifluorsyl)phenyl azo) salicylaldehyde.
Abstract: Abstract Searching for new anti-inflammatory and analgesic agents, we have prepared a series of novel pyrazoles containing benzofuran and trifluoromethyl moieties. The pyrazole derivatives have been synthesized via two routes starting from 5-(3-(trifluoromethyl)phenyl azo) salicylaldehyde. The first route involved the synthesis of 2-acetylbenzofuran and then treatment with aldehydes to afford the corresponding chalcones. The cyclization of the latter chalcones with hydrazine hydrate led to the formation of new pyrazoline derivatives. The second route involved the synthesis of benzofuran-2-carbohydrazide and then treatment with formylpyrazoles, chalcones and ketene dithioacetal derivatives to afford the corresponding pyrazole derivatives. Some of the synthesized compounds exhibited anti-inflammatory and analgesic activities.
21 citations
TL;DR: In this paper, the ultrasound assisted preparation of 2-(1H-tetrazol-5-yl) acrylonitrile derivatives via a one-pot multi-component method is described successfully using ZrP2O7 nanoparticles as a catalyst.
Abstract: Abstract The ultrasound-assisted preparation of 2-(1H-tetrazol-5-yl) acrylonitrile derivatives via a one-pot multi-component method is described successfully using ZrP2O7 nanoparticles as a catalyst. Readily available tetrazoles can be transformed into the corresponding 1,5- and 2,5-disubstituted tetrazoles. 2,4′-Dibromoacetophenone gave the corresponding 2,5-disubstituted derivative as the only isomer. Synthesis of tetrazole derivatives with excellent yields in short times, a wide range of products under ultrasound irradiation, environmental benignity and a simple work-up procedure are some of the important features of this protocol.
21 citations
TL;DR: In this paper, the Raman spectrum of a single crystal of Gd4(BO2)O5F comprises a single peak at 1364 cm−1 assigned to the only Raman-active vibrational mode νs of the linear triatomic O-B-O units besides very weak peaks at 805 and 2083 cm− 1 (presumably the respective δ and νas modes).
Abstract: Abstract Gadolinium borate fluoride oxide Gd4(BO2)O5F crystallises in space group Pmmn (no. 59, a = 1574.6(4), b = 381.42(7), c = 660.88(11) pm, 565 refl., 28 parameters, R1 = 0.039, wR2 = 0.128, twin refinement) and comprises linear BO2− anions between closely packed [GdO] layers formed by OGd4 tetrahedra and terminated by oxygen and fluorine atoms. The crystal structure’s relationship with the NiAs type is illustrated. The Raman spectrum recorded on a single crystal of Gd4(BO2)O5F comprises a single peak at 1364 cm−1 assigned to the only Raman-active vibrational mode νs of the linear triatomic O–B–O units besides very weak peaks at 805 and 2083 cm−1 (presumably the respective δ and νas modes).
17 citations
TL;DR: In this article, the missing members of the REPd₅Al₂ (RE = Tb-Yb) series as well as on the new REPt₆Alↆ series were synthesized and structurally and magnetically characterized.
Abstract: REPd₅Al₂ compounds with RE = Ce–Gd as well as Y and Lu have been previously synthesized. Although some compounds with the small lanthanides also exist, the compounds with intermediate-sized rare-earth elements (RE = Tb–Yb) had not been prepared. We report on the missing members of the REPd₅Al₂ (RE = Tb–Yb) series as well as on the new REPt₅Al₂ (RE = Y, Gd–Tm, Lu) series, which we have synthesized and structurally as well as magnetically characterized. All members crystallize isostructurally in the ZrNi₂Al₅ type with an anti-arrangement of the T = Pd/Pt and Al atoms. YPd₅Al₂ and LuPd₅Al₂, as well as the respective platinum homologs, YPt₅Al₂ and LuPt₅Al₂, have been characterized also by ²⁷Al magic-angle spinning nuclear magnetic resonance spectroscopy. Consistent with the XRD analysis, the spectra indicate the existence of only one distinct Al site in the structure.
17 citations
TL;DR: In this article, the asymmetric unit of the title structure consists of one dication, two triiodide anions, and one iodine molecule, all located in general positions in the non-centrosymmetric space group P1.
Abstract: The reaction of S-nicotine with hydroiodic acid in the presence of iodine gave the new polyiodide-containing salt nicotine-1,1′-diium bis(triiodide)-diiodine (1/1) (C₁₀H₁₆N₂) [I₃]₂·I₂ (1). The title compound has been characterised by spectroscopic methods (Raman and IR) and single-crystal X-ray diffraction. The asymmetric unit of the title structure consists of one dication, two triiodide anions, and one iodine molecule, all located in general positions in the non-centrosymmetric space group P1. One of the two crystallographically independent triiodide anions and the doubly protonated nicotinium dication form hydrogen-bonded chains along b, which are arranged parallel to each other in the ½bc plane. The second crystallographically independent triiodide anion and the iodine molecule form an I₅– moiety, which is end-on connected to two symmetry-related anions resulting in polyiode zig–zag chains along the [0 1 1] direction. These polyiodide chains are stacked parallel to each other in the 0bc plane. The Raman spectrum of the title compound shows characteristic lines in the 50–200 cm–¹ range, which are in excellent agreement with the findings derived from the crystal structure.
17 citations
TL;DR: In this paper, 10 1,2,4,5-tetra-substituted imidazole derivatives have been synthesized with a 2-hydroxyethy substituent at the 1-nitrogen atom and potentially electron releasing hydroxy-, methoxy-, dimethylamino- or nitro substituents in various positions on the benzene ring located on the 2-carbon atom.
Abstract: Abstract Ten 1,2,4,5-tetra-substituted imidazole derivatives have been synthesized with a 2-hydroxyethy substituent at the 1-nitrogen atom and potentially electron releasing hydroxy-, methoxy-, dimethylamino- or nitro substituents in various positions on the benzene ring located on the 2-carbon atom. The prototypical derivative with an unsubstituted phenyl ring at the 2-position is also reported. The compounds are obtained in excellent yields (average 86%) via a four-component cyclocondensation reaction of benzil, ethanolamine, and the appropriate aromatic carbaldehyde together with ammonium acetate. The reaction uses a novel ionic liquid catalyst, DEAHS (diethyl ammonium hydrogen sulfate), under solvent-free conditions and a green synthetic protocol. The key advantages of this process are high yield, shorter reaction times and ease of work-up. Furthermore, the products can be purified by a non-chromatographic method and the catalyst is re-usable. All of these newly synthesized compounds have been characterized from spectral data; the X-ray structures of three representative molecules are also detailed.
16 citations
TL;DR: In this paper, three new acesulfamate salts, NaC4H4NO4S, RbC4 H4 NO4S and CsC4 h4NO 4S, were prepared by reactions in aqueous solutions and thoroughly characterized by X-ray diffraction methods.
Abstract: Abstract Three new acesulfamate salts, NaC4H4NO4S, RbC4H4NO4S and CsC4H4NO4S, were prepared by reactions in aqueous solutions and thoroughly characterized. Their crystal and molecular structures were determined by single crystal X-ray diffraction methods. They crystallize in the monoclinic space group P21/a with a = 7.2518(2), b = 8.9414(4), c = 10.5929(4) Å, β = 99.951(3)°, V = 676.52(4) Å3 for the Na salt; a = 7.4663(3), b = 9.6962(4), c = 10.4391(4) Å, β = 95.150(3)°, V = 752.68(5) Å3 for the Rb salt and a = 7.5995(4), b = 9.9439(4), c = 10.8814(6) Å, β = 91.298(5)°, V = 822.08(7) Å3 for the Cs salt, and Z = 4 molecules per unit cell. The three compounds are isotypic to each other and to the previously reported potassium salt. The metal ions are in irregular polyhedral coordination with six neighboring acesulfamate anions through their nitrogen and carbonyl and sulfoxide oxygen atoms. The FTIR spectra of the compounds were also recorded and are briefly discussed.
15 citations
TL;DR: In this article, a new series of fused 1,2,4-triazoles, namely 6-aryl-3-(furan-2-yl)-[1, 2, 4]triazolo[3, 4-b][1, 3, 4]-thiadiazoles 3a-h and 4a-f as well as 6-yl-3(furan 2-yl)7H]-1,2.4]-triazole-3-thiol (2) were synthesized by the condensation of 4-amino
Abstract: A new series of fused 1,2,4-triazoles, namely 6-aryl-3-(furan-2-yl)-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles 3a–h and 4a–f as well as 6-aryl-3-(furan-2-yl)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazines 5a–h, were synthesized by the condensation of 4-amino-5-(furan-2-yl)-4H-1,2,4-triazole-3-thiol (2) with substituted aromatic acids and phenacyl bromides, respectively. The structures of the newly synthesized compounds were established using spectroscopic analysis, while that of 3e was confirmed independently by a single-crystal X-ray structure determination. The compounds were evaluated for their antiviral activity against the replication of HIV-1 and HIV-2 in MT-4 cells using an MTT assay. In a docking study, 4b interacted with several amino acids in the reverse transcriptase (RT) binding site of HIV-1. Some new analogues were selected for evaluation of their Eg5 inhibitory activity using an in vitro malachite green ATPase assay. The QSAR of these new analogues was studied as well.
14 citations
TL;DR: In this article, the equiatomic CeXX′ phases (X and X′ = elements of the 3ʳᵈ, 4ᵃ, or 5ᵃ main group) extend the large series of CeTX intermetallics (T = electron-rich transition metal).
Abstract: The equiatomic CeXX′ phases (X and X′ = elements of the 3ʳᵈ, 4ᵗʰ, or 5ᵗʰ main group) extend the large series of CeTX intermetallics (T = electron-rich transition metal). These phases crystallize with simple structure types, i.e. ZrNiAl, TiNiSi, CeScSi, α-ThSi₂, AlB₂, and GdSi₂. In contrast to the CeTX intermetallics one observes pronounced solid solutions for the CeXX′ phases. The main influence on the magnetic ground states results from the absence of d electrons. All known CeXX′ phases show exclusively trivalent cerium and antiferro- or ferromagnetic ordering at low temperatures. The crystal chemical details and some structure-property relationships are reviewed.
TL;DR: In this article, a simple fluorescent naphthalimide-based receptor Nallyl-4-iminodi(N-butylacetamide)-1,8-naphthimide 3 was carried out as a selective picrate (Pic)-) anion probe, and the detecting behavior of this probe was studied by fluorescence spectroscopy.
Abstract: Abstract The synthesis of a simple fluorescent naphthalimide-based receptor N-allyl-4-iminodi(N-butylacetamide)-1,8-naphthalimide 3 was carried out as a selective picrate (Pic–) anion probe, and the detecting behavior of this probe was studied by fluorescence spectroscopy. In DMF solution, the interaction of compound 3 with different anions, including Pic–, F–, Cl–, Br–, I–, OH–, Ac–, NO3–, ClO4–, SCN–, SO32–, SO42–, H2PO4–, and HPO42–, revealed significant fluorescence quenching only with the Pic– anion. By adding the picrate anions, green-yellow fluorescence emission quenches, which is easily observed by naked eyes under a 365 nm UV light irradiation. This phenomenon is essential for producing a highly selective and sensitive fluorescent probe for picrate anions. The probe can be applied to the quantification of Pic– with a linear range covering from 4.97 × 10–6 to 6.82 × 10–5 m and a detection limit of 5.8 × 10–7 m. Most importantly, probe 3 has a high selectivity for picrate over competitive anions and picrate-containing analytes, which meet the selective requirements for practical application. Thus, the present results would be inspiring findings in the future design of reaction-based fluorescent turn-off probes for the environmentally relevant picrate probe.
TL;DR: In this article, the authors used nanoparticles as an efficient catalyst for the three-component reaction of 6-aminouracil, aromatic aldehydes, and urea in water to give the title compounds of type (IV).
Abstract: Cu nanoparticles are found to be an efficient catalyst for the three-component reaction of 6-aminouracil (I), aromatic aldehydes (II), and urea (III) in water to give the title compounds of type (IV).
TL;DR: In this paper, a series of substituted 6′-(4-chlorophenyl)-3,4′-bipyridine-3′-carbonitriles with incorporated pyrazole and/or triazole moieties have been synthesized using 2.acetohydrazide (3) as starting material.
Abstract: Abstract A series of novel substituted 6′-(4-chlorophenyl)-3,4′-bipyridine-3′-carbonitriles with incorporated pyrazole and/or triazole moieties have been synthesized using 2-(6′-(4-chlorophenyl)-3′-cyano-3,4′-bipyridin-2′-yloxy)acetohydrazide (3) as starting material. Also, the key intermediate 3 reacted with aromatic aldehydes and tosyl chloride to give the corresponding Schiff bases and tosyl hydrazide derivatives, respectively. The antimicrobial of these newly synthesized compounds was evaluated against Bacillus subtilis as Gram-positive bacteria and Trichoderma viride as a fungus; some of these compounds such as 5, 6, 7, 8, 10, 12, and 14 showed excellent activities as antimicrobial agents. Moreover, the cytotoxic activity of the most active compounds was assessed in vitro against human tumor liver cancer cell line (HEPG2); compounds 8, 10, 13a, and 14 showed potent activities relative to Doxorubicin which was used as a reference standard drug in this study.
TL;DR: In this article, a new dimeric naphtho-γ-pyrone, 2-hydroxydihydronigerone, along with five compounds, nigerone (2), pyrophen (3), kojic acid (4), 4-(hydroxymethyl)-5-hydroxy-2H-polypyran-2-one (5), and p-Hydroxyphenylacetic acid (6), was isolated from an endophytic fungus Aspergillus niger AKRN associated with the roots of Entand
Abstract: Abstract A new dimeric naphtho-γ-pyrone, 2-hydroxydihydronigerone (1), along with five compounds, nigerone (2), pyrophen (3), kojic acid (4), 4-(hydroxymethyl)-5-hydroxy-2H-pyran-2-one (5), and p-hydroxyphenylacetic acid (6), was isolated from an endophytic fungus Aspergillus niger AKRN associated with the roots of Entandrophragma congoënse. The structure of the new compound has been elucidated using spectroscopic data including 1D and 2D NMR as well as the high-resolution mass spectrometry. Compounds 1–5 showed weak antimicrobial activity on five selected Gram-negative bacteria, namely Enterobacter aerogenes (CM64), Enterobacter cloacae (BM67), Klebsiella pneumonia (K2), and Escherichia coli (ATCC8739 and ATCC10536).
TL;DR: The new title compound was prepared by arc melting of the pure elements (annealing at 870 K for 2 months, yield given in g) as mentioned in this paper, and it was used in the construction of the new title compounds.
Abstract: The new title compound is prepared by arc melting of the pure elements (annealing at 870 K for 2 months, yield given in g).
TL;DR: In this paper, two new complexes, {Cd(immb)I2]·DMF}n (1) and {cd3immb)(btc)2][H2O]n (2) (immb = 2-(1H-imidazol- 1-methyl)-6-methyl-1-benzimidaze, btc = 1,2,3-benzenetricarboxylate, DMF = dimethyl formamide), were synthesized and characterized.
Abstract: Abstract Two new complexes, {[Cd(immb)I2]·DMF}n (1) and {[Cd3(immb)(btc)2]·H2O}n (2) (immb = 2-(1H-imidazol- 1-methyl)-6-methyl-1H-benzimidazole, btc = 1,2,3-benzenetricarboxylate, DMF = dimethyl formamide), have been synthesized and characterized. Single crystal X-ray diffraction shows that 1 exhibits a chain structure constructed by immb ligands bridging Cd(II) ions. In 2, Cd(II) ions are linked by immb ligands with bridging mode and btc3– anions with the μ2-η2:η1 bonding pattern leading to a 2D structure. Luminescent properties have been investigated in the solid state at room temperature.
TL;DR: In this article, the synthesis of isatin Schiff bases incorporating a benzoylpiperidine, benzoylmorpholine and 1,4-dibezoy-lpiperazine moiety and their N-Mannich bases was investigated.
Abstract: Abstract The mixed azines 3a–h and 4 were obtained by treating 3-hydrazonoindolin-2-one (2) with the appropriate aldehyde or dialdehyde. Treatment of 3b or 3c with formaldehyde or glutaric dialdehyde and the appropriate amine afforded the azine Mannich bases 5–7. The condensation of isatin or its N-Mannich base 8 with 1-aminopiperidine, 4-aminomorpholine and 1,4-diaminopiperazine gave 10a–d, 12 and 13. The Mannich bases 14 and 15 were obtained from 10a and 10b. Treatment of 2 with succinic, phthalic and quinolinic anhydride and pyromellitic dianhydride afforded compounds 16, 17a, 17b and 18, respectively. The synthesis of isatin Schiff bases incorporating a benzoylpiperidine, benzoylmorpholine and 1,4-dibezoylpiperazine moiety and their N-Mannich bases was investigated.
TL;DR: In this paper, the Ce3Pd6Sb5-type rare earth stannides RE3Au6Sn5 (RE = La, Ce, Pr, Nd, Sm) were synthesized by arcmelting of the elements and subsequent annealing in open tantalum crucibles within sealed evacuated silica ampoules.
Abstract: Abstract The Ce3Pd6Sb5-type rare earth stannides RE3Au6Sn5 (RE = La, Ce, Pr, Nd, Sm) were synthesized by arc-melting of the elements and subsequent annealing in open tantalum crucibles within sealed evacuated silica ampoules. The polycrystalline samples were studied by powder X-ray diffraction. The structures of three crystals were refined from single crystal X-ray diffractometer data: Pmmn, a = 1360.3(9), b = 455.9(2), c = 1023.6(4) pm, wR2 = 0.0275, 1069 F2 values, 48 variables for Ce3Au6Sn5, a = 1352.4(4), b = 455.1(1), c = 1023.7(3) pm, wR2 = 0.0367, 1160 F2 values, 48 variables for Nd3Au6Sn5, and a = 1339.8(2), b = 452.80(7), c = 1012.4(2) pm, wR2 = 0.1204, 1040 F2 values, 49 variables for Sm3Au5.59(2)Sn5.41(2). One of the gold sites of the samarium compound shows a significant degree of Au/Sn mixing. The RE3Au6Sn5 structures are composed of three-dimensional [Au6Sn5] polyanionic networks with the two crystallographically independent rare earth atoms in larger cages, i.e., RE1@Au10Sn6 and RE2@Au8Sn8. The [Au6Sn5] network is stabilized by Au–Sn (266–320 pm), Au–Au (284–301 pm) as well as Sn–Sn (320 pm; distances given for the cerium compound) interactions. Temperature-dependent magnetic susceptibility measurements reveal an antiferromagnetic ordering only for Sm3Au6Sn5, while the other compounds exhibit Curie–Weiss paramagnetism. 119Sn Mössbauer spectroscopy shows resonances in the typical range for intermetallic tin compounds where tin takes part in the polyanionic network [isomer shifts between 1.73(1) and 2.28(1) mm·s−1]. With the help of theoretical electric field gradient calculations using the WIEN2k code it was possible to resolve the spectroscopic contributions of all three crystallographically independent atomic tin sites in the 119Sn spectra of RE3Au6Sn5 (RE = La, Ce, Pr, Nd, Sm).
TL;DR: In this article, the isothermal section of the Tm-Ni-In system at T = 870 K was constructed and a broad substitution of Ni for In was observed for TmNi1−0.60In1−1.40, and of Tm for In for the tmNi2−TmNi4In section.
Abstract: Abstract The isothermal section of the Tm–Ni–In system at T = 870 K was constructed. Nine ternary compounds: Tm10Ni9In20, TmNi1–0.60In1–1.40, Tm2Ni2In, Tm2Ni1.78In, Tm5Ni2In4, Tm11Ni4In9, Tm4.83Ni2In1.17, Tm6Ni2In and Tm14Ni3In3 exist in the system at the temperature of investigation. Solid solutions with In/Ni and Tm/In mixing were noticed for numerous compounds. A broad substitution of Ni for In was observed for TmNi1–0.60In1–1.40, and of Tm for In for the TmNi2–TmNi4In section. An interstitial solid solution TmxNiIn, based on binary equiatomic NiIn, extends up to 8 at.% Tm (x = 0.17). The magnetic properties of TmNiIn, Tm2Ni2In and Tm5Ni2In4 are also reviewed.
TL;DR: The compound H₅C₆(H)Ge[C(GaCMe₃)=C(HCMe), 2, was isolated in trace quantities from the reaction of Et₂N-Ge(C≡C-CMe) with excess H-Ga(CMe, 2).
Abstract: The compound H₅C₆(H)Ge[C(GaCMe₃)=C(H)CMe₃]₂(μ-H)₃[Ga(CMe₃)₂], 2, was isolated in trace quantities from the reaction of Et₂N–Ge(C≡C–CMe₃)₃ with excess H–Ga(CMe₃)₂. Compound 2 has a unique molecular structure with a Ga₃H₃ heterocycle of which one Ga–H–Ga group is bridged by a dialkenylgermanium unit. The molecular structure of a second compound (3) is reported, which may be described as a spiro-germane and has AlNGeC and AlC₂Ge heterocycles. The rings are formed by intramolecular Al–N and Al–C interactions.
TL;DR: In this article, the crystal structure of a complex of thioureas and thiocyanate was determined by X-ray crystallography, and it was shown that the complex exists in the form of a chain-like polymer comprising [Ag(μ₂-Diaz)(μ-SCN)] units.
Abstract: Silver(I) complexes of thioureas and thiocyanate, [(Tu)AgSCN], [(Metu)AgSCN], [(Dmtu)AgSCN], [(Tmtu)(AgSCN)₁.₅], [(Imt)AgSCN], and [(Diaz)AgSCN] (where Tu = thiourea, Metu = N-methylthiourea, Dmtu = N,N′-dimethylthiourea, Tmtu = N,N,N′,N′-tetramethylthiourea, Imt = 1,3-imidazolidine-2-thione, and Diaz = 1,3-diazinane-2-thione), have been prepared and characterized by elemental analysis, IR and NMR spectroscopy, and thermal analysis. The crystal structure of one of them, [(Diaz)Ag(SCN)] (1), was determined by X-ray crystallography. The crystal structure of 1 shows that the complex exists in the form of a chain-like polymer comprising [Ag(μ₂-Diaz)(μ₂-SCN)] units. The silver atoms are bridged by μ₂-thione sulfur atoms of Diaz and μ₂-thiocyanate sulfur atoms. Thereby each silver atom adopts a distorted tetrahedral coordination environment comprising four sulfur atoms, two from thione and two from thiocyanate ligands. An upfield shift in the >C=S resonance of thiones in ¹³C NMR and a downfield shift in the N–H resonance in ¹H NMR are consistent with the sulfur coordination to silver(I). The appearance of a band around 2100 cm–¹ in the IR and a resonance around 125 ppm in the ¹³C NMR spectrum indicates the binding of thiocyanate to silver(I).
TL;DR: Pittangretosides L (1) and C1 (2) were isolated from the leaves of Pittosporum angustifolium Lodd and their structures were established by NMR spectroscopic, mass spectrometric and chemical means as mentioned in this paper.
Abstract: Abstract Two new taraxastane-type triterpene saponins, named pittangretosides L (1) and C1 (2), were isolated from the leaves of Pittosporum angustifolium Lodd. Their structures were established by NMR spectroscopic, mass spectrometric and chemical means. The in vitro cytotoxicity was evaluated against four cell lines. The compounds exhibited no cytotoxic activity up to a concentration of 130 μm.
TL;DR: In this article, the synthesis of two new copper(II) complexes with benzimidazole type ligands, Cu(tta)2(L1)2 (1), where L1 is 3-(4-(1H-benzo[d]dimidazol-1-yl)-4-methoxy phenyl)-1-phenylprop-2-en-one-one; tta is 2-thenoyltrifluoroacetonate, are reported.
Abstract: Abstract The synthesis of two new copper(II) complexes with benzimidazole type ligands, Cu(tta)2(L1)2 (1) and Cu(tta)2(L1) (2) (where L1 is 3-(4-(1H-benzo[d]imidazol-1-yl)-4-methoxy phenyl)-1-phenylprop-2-en-1-one; tta is 2-thenoyltrifluoroacetonate), are reported. Their structures have been characterized by infrared spectroscopy, elemental analyses and single-crystal X-ray diffraction. The copper(II) ion of 1 is in a distorted octahedral environment, while that of 2 is in a distorted square-pyramidal environment. In both cases, the donor atoms are provided by oxygen atoms of the tta ligands and nitrogen atoms of the L1 ligands.
TL;DR: A series of 3-aryl-6-adamantylmethyl-[1,2,4]triazolo[3,4-b][1,3, 4]thiadiazoles 6a−l were synthesized by a simple method with the aim of developing novel HIV non-nucleoside reverse transcriptase inhibitors as discussed by the authors.
Abstract: Abstract A series of novel 3-aryl-6-adamantylmethyl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles 6a–l were synthesized by a simple method with the aim of developing novel HIV non-nucleoside reverse transcriptase inhibitors. All the synthesized compounds were structurally confirmed by spectral analyses. The structure of 6a was unambiguously verified by X-ray structure determination. The synthesized compounds were evaluated for their anti-HIV activity and four analogs displayed moderate inhibitory activity with EC50 values ranging from 10.10 to 12.40 μg mL–1. Molecular docking of 6g with HIV-1 reverse transcriptase was studied to rationalize some structure-activity relationships (SARs).
TL;DR: In this paper, several samples of the solid solutions CeRu0.28Pd0.34Sn and CeRh0.72Sn were synthesized by arc-melting and characterized by X-ray powder diffraction.
Abstract: Abstract Several samples of the solid solutions CeRu1–xPdxSn and CeRh1–xPdxSn have been synthesized by arc-melting and characterized by X-ray powder diffraction. Guinier powder patterns prove that the ZrNiAl-type structure is the dominating one, besides the CeRuSn and TiNiSi type structures. The structures of CeRu0.28Pd0.72Sn (ZrNiAl type, P6̅2m, a = 751.95(3), c = 418.70(2) pm, wR2 = 0.0274, 332 F2 values, 14 variables) and CeRh0.66Pd0.34Sn (ZrNiAl type, P6̅2m, a = 750.26(3), c = 411.59(2) pm, wR2 = 0.0533, 358 F2 values, 14 variables) were refined from single crystal diffractometer data. Magnetic measurements in combination with XANES (X-Ray Absorption Near Edge Structure) clearly proved intermediate cerium valencies for most compounds and revealed the best fitting parameters for those with the ICF model (Interconfiguration fluctuation). The electrical resistivity is also influenced by the substitutions. At low and high valence electron counts (VECs) metallic character is present, while around the VEC of CeRhSn the typical resistivity behavior for valence fluctuating compounds is observed.
TL;DR: The rare-earth borosilicates RE3BSi2O10 (RE = Pr, Tb) were synthesized under high-temperature conditions of 1600 °C in a radio frequency furnace from praseodymium oxide, terbium oxide and boric acid.
Abstract: Abstract The rare-earth borosilicates RE3BSi2O10 (RE = Pr, Tb) were synthesized under high-temperature conditions of 1600 °C in a radio frequency furnace from praseodymium oxide, terbium oxide, silicon dioxide, silicon nitride, boron trioxide, and boric acid. The structure determinations based on powder diffraction data revealed that both phases RE3BSi2O10 (RE = Pr, Tb) are isotypic to Gd3BSi2O10 [L. Chi, H. Chen, X. Lin, H. Zhuang, J. Huang, Jiegou Huaxue 1998, 17, 297]. The compounds crystallize in the orthorhombic space group Pbca (no. 61) with eight formula units and the lattice parameters a = 982.9(2), b = 714.2(2), c = 2314.4(4) pm, V = 1.6247(4) nm3, Rp = 0.0231, and Rwp = 0.0354 (all data) for Pr3BSi2O10 and a = 960.5(5), b = 692.1(3), c = 2272.4(1) pm, V = 1.5106(2) nm3 for Tb3BSi2O10. The lattice parameters of Tb3BSi2O10 could be determined, but a final refinement of the powder data has not proved satisfactory. The structure of Pr3BSi2O10 exhibits eight- (Pr1) and ninefold coordinated rare-earth cations (Pr2 and 3). Layers of ortho-silicate anions [SiO4]4– and borosilicate anions [BSiO6]5– are arranged alternatingly along the c axis and the RE cations are located in between.
TL;DR: In this article, a Walker-type multianvil apparatus was used to synthesize compound (III) and compound (VI) and their structures were determined by a single crystal XRD.
Abstract: Compounds (III) and (VI) are synthesized in a Walker-type multianvil apparatus and their structures are determined by single crystal XRD.
TL;DR: In this paper, single crystals of NaRb2[N(CN)2]3·H2O (II) are obtained by mixing aqueous solutions of Na[N[N 2] and the respective alkali fluoride followed by slow H2O evaporation.
Abstract: Single crystals of KCs[N(CN)2]2 (I) and NaRb2[N(CN)2]3·H2O (II) are obtained by mixing aqueous solutions of Na[N(CN)2] and the respective alkali fluoride followed by slow H2O evaporation.
TL;DR: In this paper, it was shown that coupling constants 1J(13C,11B) can be obtained by measuring the respective line widths of 13C(B-C) and 11B NMR signals.
Abstract: Abstract Care should be taken on recording the sometimes elusive 13C NMR signals for boron-bonded carbon atoms, since it is easy to extract information about coupling constants 1J(13C,11B) by measuring the respective line widths of 13C(B-C) and 11B NMR signals. This information can be confirmed by quantum-chemical calculations [B3LYP (6-311+G(d,p) level of theory] of nJ(13C,11B) in organoboranes and tetraorganoborates. For the latter, the signs for n = 2, 3, 4 were experimentally determined.