Zeitschrift für Naturforschung B最新文献

{"title":"Synthesis, anti-HIV and cytotoxicity evaluation of chiral 2,5-disubstituted 1,3,4-thiadiazole derivatives bearing the sulfonamide scaffold","authors":"Anum Israr, Shahid Hameed, Najim A. Al-Masoudi","doi":"10.1515/znb-2023-0078","DOIUrl":"https://doi.org/10.1515/znb-2023-0078","url":null,"abstract":"In the present study, chiral 2-(4-substiuted phenyl)amino-5-[1-(4-substituted benzenesulphonamido)alkyl]-1,3,4-thiazdiazoles 5a–x were synthesized from enantiopure <jats:sc>l-</jats:sc>amino acids in a multistep sequence. The starting acids were reacted with arylsulphonyl chlorides to produce <jats:italic>N</jats:italic>-arylsulfonyl amino acids 1a–h, followed by esterification to obtain the corresponding esters 2a–h. Treatment of esters with hydrazine hydrate afforded the corresponding hydrazides 3a–h. The coupling of hydrazides with aryl isothiocyanates followed by cyclization gave the target thiadiazoles 5a–x in good yields. The new synthesized compounds were assayed against HIV-1 and HIV-2 in MT-4 cells using MTT assay. Compounds 5s, 5v and 5w showed IC<jats:sub>50</jats:sub> values of &gt; 1.58, &gt;1.98 and &gt; 2.04 μ<jats:sc>m</jats:sc> with SI &gt; 1, respectively, indicating that these compounds were cytotoxic at concentrations values of 1.58, 1.98 and 2.04 μ<jats:sc>m</jats:sc>, respectively.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"255 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139770503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Expansion and adaptation of the M5B12O25(OH) structure type to incorporate di- and trivalent transition metal cations","authors":"Leonard C. Pasqualini, Martina Tribus, H. Huppertz","doi":"10.1515/znb-2023-0082","DOIUrl":"https://doi.org/10.1515/znb-2023-0082","url":null,"abstract":"Abstract Five transition metal borates were synthesized in a Walker-type module under high-pressure/high-temperature conditions of 8–9 GPa and 800–1200 °C. They all exhibit the same interpenetrating, anionic borate network B12O2616−, crystallizing in the space group I41/acd, and therefore show high similarities to the borates Ti5B12O26 and Ga5B12O25(OH). Cr5B12O25(OH) and V5B12O25(OH) are isotypic to Ga5B12O25(OH), whereas Mn5Mn0.83B12O26 and Fe5Fe0.14B12O24.3(OH)1.7 feature the partial occupation of an additional, cuboctahedral cavity in the structure. This is due to a partial reduction of the cations to the oxidation state +2, as presented with the novel compound Mn5MnB12O22(OH)4, which only features Mn2+ for charge compensation. These structures feature a twelvefold coordination of manganese and iron.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"122 2","pages":"39 - 49"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139453813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Die Serie caesiumhaltiger Thioarsenate(V) der Lanthanoide vom Formeltyp Cs3Ln[AsS4]2 mit Ln = La–Nd und Sm","authors":"K. Engel, T. Schleid","doi":"10.1515/znb-2023-0066","DOIUrl":"https://doi.org/10.1515/znb-2023-0066","url":null,"abstract":"Abstract Cesium-containing thioarsenates(V) of lanthanoids with the composition Cs3Ln[AsS4]2 can be prepared for Ln = La–Nd and Sm by the oxidation of the lanthanoid metals in the presence of orpiment (As2S3), cesium sesquisulfide (Cs2S3) and elemental sulfur (S). The reaction mixtures were handled under argon atmosphere and heated in fused silica ampoules to a moderate reaction temperature of 500 °C. Single crystals of this Cs3Ln[AsS4]2 series appear as yellowish, transparent rods that are not stable to moist air and water. Their monoclinic crystal structure was determined from single-crystal X-ray diffraction data. The cesium-containing thioarsenates(V) Cs3Ln[AsS4]2 with Ln = La–Nd and Sm crystallize isotypically with Rb3Sm[PS4]2 in the non-centrosymmetric monoclinic space group P21 with Z = 2. The lattice parameters range between a = 997–1015 pm, b = 699–703 pm, c = 1192–1195 pm and β = 90.2–90.4°. There are two crystallographically different As5+ cations and one unique Ln3+ cation present, all coordinated by sulfur anions. Tetrahedral [AsS4]3− anions form two functionally different units working either as bridging units between three Ln3+ cations or as terminal ligands for Ln3+. [LnS8]13− polyhedra form ∞ 1 { [ Ln S 2 / 2 v S 6 / 1 t ] 11 − } ${}_{infty }^{1}left{{[mathit{Ln}{mathrm{S}}_{2/2}^{mathrm{v}}{mathrm{S}}_{6/1}^{mathrm{t}}]}^{11-}right}$ chains propagating along [010], which are separated by Cs+ cations with coordination numbers as high as C.N. = 9, 10 and 11. Surprisingly, the eighth interatomic distance d(Ln–S3) does not follow the lanthanoid contraction, but increases with decreasing ionic radius, changing the coordination polyhedron of Ln3+ from a bicapped to a monocapped trigonal prism upon the transition from Nd to Sm, and causing a structural break in the crystal structure of this series. The results of Raman spectroscopic measurements on single crystals of Cs3La[AsS4]2 have confirmed the presence of [AsS4]3− tetrahedra as structural building blocks.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"17 15","pages":"29 - 38"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139455953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Me3N(C6H3(CF3)2)][BF4] and [Me3N(C6H3(CH3)2)][BF4], as potential synthons for non-covalent supramolecular assembly","authors":"J. R. Schmid, Anja Wiesner, P. Voßnacker, Martin Jansen, Sebastian Riedel","doi":"10.1515/znb-2023-0095","DOIUrl":"https://doi.org/10.1515/znb-2023-0095","url":null,"abstract":"Abstract The compounds [Me3N(C6H3(CF3)2)][BF4] and [Me3N(C6H3(CH3)2)][BF4] were synthesized from commercially available starting materials and fully characterized by single-crystal X-ray diffraction, NMR, IR and Raman spectroscopy, as well as mass spectrometry. Both ammonium cations show potential for applications in crystal engineering due to their structure directing properties in the solid state.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"90 26","pages":"57 - 61"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139454398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A solid-state 171Yb NMR-spectroscopic characterization of selected divalent ytterbium intermetallics","authors":"Josef Maximilian Gerdes, Lars Schumacher, Michael Ryan Hansen, Rainer Pöttgen","doi":"10.1515/znb-2023-0070","DOIUrl":"https://doi.org/10.1515/znb-2023-0070","url":null,"abstract":"Abstract The intermetallic ytterbium compounds YbZnSn, YbPdSn2, YbAuIn2 and their calcium-substituted counterparts Yb0.5Ca0.5ZnSn, Yb0.5Ca0.5PdSn2 and Yb0.5Ca0.5AuIn2 were synthesized by reaction of the elements in sealed tantalum tubes in an induction furnace. The samples were characterized by X-ray powder diffraction. Their static, temperature-dependent solid-state 171Yb NMR spectra exhibit strong positive Knight shifts without any significant temperature dependence. The resonance shifts including anisotropy parameters for the ternary compounds have been determined.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"18 12","pages":"13 - 19"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139456895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis and structure refinement of the zinc hydroxide boracite: Zn3B7O13(OH)","authors":"Raimund Ziegler, Sabrina Jungmann, H. Huppertz","doi":"10.1515/znb-2023-0096","DOIUrl":"https://doi.org/10.1515/znb-2023-0096","url":null,"abstract":"Abstract The new zinc borate Zn3B7O13(OH) crystallizes trigonally in the space group R3c (no. 161) with the lattice parameters a = 849.76(3), c = 2099.8(2) pm, V = 1.3131(2) nm3, and six formula units per unit cell (Z = 6). It was synthesized at high-pressure/high-temperature conditions in a multianvil device. Single-crystal and powder X-ray diffraction experiments were conducted.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"31 7","pages":"51 - 55"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139455153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modifying the valence phase transition in Eu2Al15Pt6 by the solid solutions Eu2Al15(Pt1−xT x )6 (T = Pd, Ir, Au; x = 1/6)","authors":"Stefan Engel, Lars Schumacher, Oliver Janka","doi":"10.1515/znb-2023-0072","DOIUrl":"https://doi.org/10.1515/znb-2023-0072","url":null,"abstract":"Abstract The solid solutions Eu2Al15(Pt1−xT x )6 with T = Pd, Ir, Au and x = 1/6 were prepared by arc-melting the stoichiometric mixture of the elements, and subsequent annealing. For x = 1/6, all three solid solutions adopt the same structure type as Eu2Al15Pt6 according to powder X-ray diffraction data. Since the platinide Eu2Al15Pt6 exhibits a (3 + 1)D modulated structure (approximant in space group P121/m1), only the averaged hexagonal unit cell (P63/mmc, Sc0.6Fe2Si4.9 type) was refined by the Rietveld method. Scanning electron microscopy in combination with energy-dispersive X-ray spectroscopy (SEM/EDX) showed that the degree of substitution is in line with the weighed amounts. For values of x > 1/6, no phase-pure samples could be obtained. The results of the magnetic susceptibility measurements indicate that the isoelectronic substitution of Pd for Pt lowers the temperature of the first-order valence phase transition from Ttrans = 45 K in Eu2Al15Pt6 to Ttrans = 42 K in Eu2Al15(Pt5/6Pd1/6)6. For Eu2Al15(Pt5/6Ir1/6)6 and Eu2Al15(Pt5/6Au1/6)6 a change in the electronic situation occurs since the Ir substituted compound exhibits one electron less compared to the pristine Pt compound, while Eu2Al15(Pt5/6Au1/6)6 has one additional electron. As a consequence, Eu2Al15(Pt5/6Ir1/6)6 shows a higher valence phase transition temperature of Ttrans = 52 K while for Eu2Al15(Pt5/6Au1/6)6 no such transition is obvious.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"21 19","pages":"21 - 27"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139457917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The germanides ScTGe2 (T = Fe, Co, Ru, Rh) – crystal chemistry, 45Sc solid-state NMR and 57Fe Mössbauer spectroscopy","authors":"Thomas Harmening, Samir F. Matar, Constanze Fehse, Steffen Klenner, H. Eckert, Jutta Kösters, Wilma Pröbsting, Stefan Seidel, Rainer Pöttgen","doi":"10.1515/znb-2023-0068","DOIUrl":"https://doi.org/10.1515/znb-2023-0068","url":null,"abstract":"Abstract The TiMnSi2-type (space group Pbam) germanides ScTGe2 (T = Fe, Co, Ru, Rh) were synthesized from the elements by arc-melting. Single crystals were grown by annealing sequences of the arc-melted buttons in an induction furnace. The structures of ScFeGe2, ScRuGe2 and ScRhGe2 were refined from single-crystal X-ray diffraction data. In ScRuGe2, the ruthenium atoms have distorted octahedral germanium coordination (242–268 pm Ru–Ge). Three trans-face-sharing octahedra form a sub-unit which is condensed via common edges in c direction and connected via common corners with four adjacent blocks, forming a three-dimensional [RuGe2 type] substructure. The two crystallographically independent scandium sites have coordination numbers 15 (Sc1@Ge8Ru4Sc3) and 17 (Sc2@Ge7Ru6Sc4). Electronic band structure calculations for ScCoGe2 and ScRuGe2 show a net charge transfer from the scandium to the transition metal and germanium atoms, leading to a description with polyanionic networks Scδ+[TGe2]δ−. The two crystallographically independent Sc sites are easily distinguishable by 45Sc magic-angle spinning (MAS)-NMR spectroscopy. Isotropic chemical shift values and nuclear electric quadrupolar interaction parameters were deduced from an analysis of the triple-quantum (TQ)-MAS NMR spectra. The electric field gradient parameters deduced from these experiments are in good agreement with quantum-chemical calculations using the Wien2k code. Likewise, the two crystallographically independent iron sites in ScFeGe2 could be discriminated in the 57Fe Mößbauer spectra through their isomer shifts and quadrupole splitting parameters: δ = 0.369(1) mm s−1 and ∆EQ = 0.232(2)  mm s−1 for Fe1 and δ = 0.375(2) mm s−1 and ∆EQ = 0.435(4) mm s−1 for Fe2 (data at T = 78 K).","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"39 8","pages":"1 - 12"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139454889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Die Geschichte der Chemie an der Ludwig-Maximilians-Universität München, mit zahlreichen Kurzbiographien von Professoren, die an der LMU gewirkt haben. von Wolfgang Beck","authors":"H. Schmidbaur","doi":"10.1515/znb-2023-0104","DOIUrl":"https://doi.org/10.1515/znb-2023-0104","url":null,"abstract":"","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"49 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138943765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simultaneous different mechanisms for the efficient synthesis of β-enaminones: 12-tungstocobaltic acid-supported on nano silica as an electron transfer and Brønsted acid nano catalyst","authors":"Mahtab Razlansari, Masoud Kahrizi","doi":"10.1515/znb-2023-0045","DOIUrl":"https://doi.org/10.1515/znb-2023-0045","url":null,"abstract":"In the present study, 12-tungestocobaltic acid, H<jats:sub>5</jats:sub>CoW<jats:sub>12</jats:sub>O<jats:sub>40</jats:sub>, was immobilized on nano silica from rice husk (CoW@NSiO<jats:sub>2</jats:sub>) to develop a novel, efficient, heterogeneous and recyclable nano catalyst for the synthesis of <jats:italic>β</jats:italic>-enaminones. It is apparent from acidity and cyclic voltammetric measurements that, the catalyst is electroactive and undergoes reversible redox transitions, as well as it is contains strong acid sites and mobile protons. As evidenced from mechanistic investigations, CoW@NSiO<jats:sub>2</jats:sub> can catalyze the synthesis of <jats:italic>β</jats:italic>-enaminones with two simultaneous ways: electron transfer and Brønsted acid mechanisms. In order to confirm the synthesis of enaminones through simultaneous mechanisms of electron transfer and acidity, the model reaction was carried out in the presence of K<jats:sub>5</jats:sub>Co as an electroactive catalyst and CoW@NSiO<jats:sub>2</jats:sub> with electron scavenger as an acid catalyst. The results showed that the reaction proceeded simultaneously through both mechanisms. There is evidence that the electron transfer property of this catalyst is most pronounced in this type of organic reactions. The catalyst demonstrated outstanding performance, and the methodology proved to be versatile, yielding excellent results across a wide range of substrates. It is worth mentioning that aliphatic amines were well-tolerated in the process and produced <jats:italic>β</jats:italic>-enaminone compounds with excellent yields and short reaction times. Also, reactions with dimedone, a cyclic 1,3-diketone, delivered moderate product yields. Additionally, the catalyst showed remarkable recyclability, maintaining its activity for a minimum of five consecutive cycles without any noticeable decline. Notably, the cyclic voltammetric and acidity measurements revealed that the catalyst’s electron transfer property and Brønsted acidity remained unchanged after five runs.","PeriodicalId":23831,"journal":{"name":"Zeitschrift für Naturforschung B","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138688084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}