A Series of Non-Oxido VIV Complexes of Dibasic ONS Donor Ligands: Solution Stability, Chemical Transformations, Protein Interactions, and Antiproliferative Activity.

A series of mononuclear non-oxido vanadium(IV) complexes, [VIV(L1-4)2] (1-4), featuring tridentate bi-negative ONS chelating S-alkyl/aryl-substituted dithiocarbazate ligands H2L1-4, are reported. All the synthesized non-oxido VIV compounds are characterized by elemental analysis, spectroscopy (IR, UV-vis, and EPR), ESI-MS, as well as electrochemical techniques (cyclic voltammetry). Single-crystal X-ray diffraction studies of 1-3 reveal that the mononuclear non-oxido VIV complexes show distorted octahedral (1 and 2) or trigonal prismatic (3) arrangement around the non-oxido VIV center. EPR and DFT data indicate the coexistence of mer and fac isomers in solution, and ESI-MS results suggest a partial oxidation of [VIV(L1-4)2] to [VV(L1-4)2]+ and [VVO2(L1-4)]-; therefore, all these three complexes are plausible active species. Complexes 1-4 interact with bovine serum albumin (BSA) with a moderate binding affinity, and docking calculations reveal non-covalent interactions with different regions of BSA, particularly with Tyr, Lys, Arg, and Thr residues. In vitro cytotoxic activity of all complexes is assayed against the HT-29 (colon cancer) and HeLa (cervical cancer) cells and compared with the NIH-3T3 (mouse embryonic fibroblast) normal cell line by MTT assay and DAPI staining. The results suggest that complexes 1-4 are cytotoxic in nature and induce cell death in the cancer cell lines by apoptosis and that a mixture of VIV, VV, and VVO2 species could be responsible for the biological activity.

Temperature-Controlled Chemoselective Synthesis of Multisubstituted 4-Alkynyl/trans 4-Alkenyl Coumarins.

A temperature-controlled facile synthesis of multisubstituted 4-alkynyl/trans 4-alkenyl coumarins with a metal salt cascade approach is reported. H2O serves both as a nucleophile and hydrogen source. The presence of metal salt facilitates the reduction of alkyne. The present protocol bypasses the structural shortcomings of the existing Sonogashira and Heck coupling reactions. In addition, the obtained 2,3-disubstituted coumarins are readily transformed into 2,3-disubstituted dihydrocoumarins, which serve as important building blocks in organic transformations.

Na9 Bi5 Os3 O24 : A Diamagnetic Oxide Featuring a Pronouncedly Jahn-Teller-Compressed Octahedral Coordination of Osmium(VI).

The Jahn-Teller (JT) theorem constitutes one of the most fundamental concepts in chemistry. In transition-element chemistry, the 3d4 and 3d9 configurations in octahedral complexes are particularly illustrative, where a distortion in local geometry is associated with a reduction of the electronic energy. However, there has been a lasting debate about the fact that the octahedra are found to exclusively elongate. In contrast, for Na9 Bi5 Os3 O24 , the octahedron around Os6+ (5d2 ) is heavily compressed, lifting the degeneracy of the t2g set of 5d orbitals such that in the sense of a JT compression a diamagnetic ground state results. This effect is not forced by structural constraints, the structure offers sufficient space for osmium to shift the apical oxygen atoms to a standard distance. The relevance of these findings is far reaching, since they provide new insights in the hierarchy of perturbations defining ground states of open shell electronic systems.

Copper(I)-Catalyzed Synthesis of Functionalized Indolizinones from Substituted Pyridine Homologated Ynones.

An efficient two-component copper-catalyzed cyclization cascade approach toward highly functionalized indolizinone heterocycles has been developed from reactions of pyridine-, isoquinoline-, and quinoline ynones, via 5-exo-dig cyclization. The catalysis involves the activation by diorgano diselenide and diorgano disulfide and also their incorporation into the indolizinone core. In addition, the obtained substituted indolizinones were readily transformed into 1-(organochalcogenyl)indolizin-2-ols, which are important building blocks in organic synthesis.

Copper(i) catalyzed synthesis of selanyl methylene 4-chromanol and aurone derivatives.

An efficient copper-catalyzed cyclization cascade approach towards highly functionalized methylene 4-chromanol and aurone derivatives has been developed from reactions of ynols via 6-exo-dig and 5-exo-dig cyclization respectively. The catalysis involves alkyne activation via diorgano-diselenides and also their regioselective incorporation into the methylene 4-chromanol and aurone derivative core and is an open-air transformation.

Synthesis of New Potential Lipophilic Co-Drugs of 2-Chloro-2'-deoxyadenosine (Cladribine, 2-CdA, Mavenclad®, Leustatin®) and 6-Azauridine (z6 U) with Valproic Acid.

2-Chloro-2'-deoxyadenosine (cladribine, 1) was acylated with valproic acid (2) under various reaction conditions yielding 2-chloro-2'-deoxy-3',5'-O-divalproyladenosine (3) as well as the 3'-O- and 5'-O-monovalproylated derivatives, 2-chloro-2'-deoxy-3'-O-valproyladenosine (4) and 2-chloro-2'-deoxy-5'-O-valproyladenosine (5), as new co-drugs. In addition, 6-azauridine-2',3'-O-(ethyl levulinate) (8) was valproylated at the 5'-OH group (→9). All products were characterized by 1 H- and 13 C-NMR spectroscopy and ESI mass spectrometry. The structure of the by-product 6 (N-cyclohexyl-N-(cyclohexylcarbamoyl)-2-propylpentanamide), formed upon valproylation of cladribine in the presence of N,N-dimethylaminopyridine and dicyclohexylcarbodiimide, was analyzed by X-ray crystallography. Cladribine as well as its valproylated co-drugs were tested upon their cancerostatic/cancerotoxic activity in human astrocytoma/oligodendroglioma GOS-3 cells, in rat malignant neuro ectodermal BT4Ca cells, as well as in phorbol-12-myristate 13-acetate (PMA)-differentiated human THP-1 macrophages. The most important result of these experiments is the finding that only the 3'-O-valproylated derivative 4 exhibits a significant antitumor activity while the 5'-O- as well as the 3',5'-O-divalproylated cladribine derivatives 3 and 5 proved to be inactive.

Guanosine Nucleolipids: Synthesis, Characterization, Aggregation and X-Ray Crystallographic Identification of Electricity-Conducting G-Ribbons.

The lipophilization of ß-d-riboguanosine (1) with various symmetric as well as asymmetric ketones is described (→3a-3f). The formation of the corresponding O-2',3'-ketals is accompanied by the appearance of various fluorescent by-products which were isolated chromatographically as mixtures and tentatively analyzed by ESI-MS spectrometry. The mainly formed guanosine nucleolipids were isolated and characterized by elemental analyses, 1 H-, 13 C-NMR and UV spectroscopy. For a drug profiling, static topological polar surface areas as well as 10 logPOW values were calculated by an increment-based method as well as experimentally for the systems 1-octanol-H2 O and cyclohexane-H2 O. The guanosine-O-2',3'-ketal derivatives 3b and 3a could be crystallized in (D6 )DMSO - the latter after one year of standing at ambient temperature. X-ray analysis revealed the formation of self-assembled ribbons consisting of two structurally similar 3b nucleolipid conformers as well as integrated (D6 )DMSO molecules. In the case of 3a ⋅ DMSO, the ribbon is formed by a single type of guanosine nucleolipid molecules. The crystalline material 3b ⋅ DMSO was further analyzed by differential scanning calorimetry (DSC) and temperature-dependent polarization microscopy. Crystallization was also performed on interdigitated electrodes (Au, distance, 5 µm) and visualized by scanning electron microscopy. Resistance and amperage measurements clearly demonstrate that the electrode-bridging 3b crystals are electrically conducting. All O-2',3'-guanosine ketals were tested on their cytostatic/cytotoxic activity towards phorbol 12-myristate 13-acetate (PMA)-differentiated human THP-1 macrophages as well as against human astrocytoma/oligodendroglioma GOS-3 cells and against rat malignant neuroectodermal BT4Ca cells.

Regional differences in type 2 diabetes treatment and outcomes in Germany-An analysis of the German DPV and DIVE registries.

AIMS: On the basis of the Diabetes Versorgungs-Evaluation (DIVE) and Diabetes-Patienten-Verlaufsdokumentation (DPV) datasets, we aimed to explore the impact of differences in treatment modalities on outcomes in Germany and put these into a global context. METHODS: The 2014 to 2016 DIVE and DPV databases were combined, and a total of 127 838 patients 18 years and older was analysed with respect to demographics, cardiovascular risk factors, comorbidities, treatments, and outcomes, separately for each German state. Estimates were expressed as adjusted least squares means together with 95% confidence intervals. RESULTS: Saarland dataset recorded the lowest mean HbA1c (6.7%; 6.6%-6.8%; 50 mmol/mol, 49-51 mmol/mol), Saxony-Anhalt showed the highest (8.3%; 8.2%-8.3%; 67 mmol/mol, 66-67 mmol/mol). The highest percentage of hypoglycaemic events was reported in Mecklenburg-West Pomerania (MWP) (4.7%; 3.9%-5.7%), the lowest in Thuringia (0.9%; 0.2%-3.4%). Metformin and sulfonylurea accounted for 36.4% to 53.3% of anti-diabetic treatments across states; other antihyperglycaemic drugs such as DPP-4 inhibitors, SGLT2 inhibitors, and GLP-1 analogues were used most often in MWP (40.0%; 37.8%-42.1%) and least in Rhineland-Palatinate (13.6%; 13.0%-14.2%). Treatment with insulin (alone or in combination) was reported most often in MWP (78.2%; 76.4%-80.0%) and least in Thuringia (26.0%; 20.1%-32.9%). CONCLUSIONS: Federal states in Germany are heterogeneous concerning diabetes treatment and associated outcomes. These data should stimulate further discussion about how optimal diabetes care can be implemented in all areas of Germany, to achieve good treatment outcomes in all federal states.

Anionic Dinuclear Oxidovanadium(IV) Complexes with Azo Functionalized Tridentate Ligands and µ-Ethoxido Bridge Leading to an Unsymmetric Twisted Arrangement: Synthesis, X-ray Structure, Magnetic Properties, and Cytotoxicity.

The synthesis of ethoxido-bridged dinuclear oxidovanadium(IV) complexes of the general formula (HNEt3)[(VOL1-3)2(µ-OEt)] (1-3) with the azo dyes 2-(2'-carboxy-5'-X-phenylazo)-4-methylphenol (H2L1, X = H; H2L2, X = NO2) and 2-(2'-carboxy-5'-Br-phenylazo)-2-naphthol (H2L3) as ligands is reported. The ligands differ in the substituents at the phenyl ring to probe their influence on the redox behavior, biological activity, and magnetochemistry of the complexes, for which the results are presented and discussed. All synthesized ligands and vanadium(IV) complexes have been characterized by various physicochemical techniques, namely, elemental analysis, electrospray ionization mass spectrometry, spectroscopic methods (UV/vis and IR), and cyclic voltammetry. X-ray crystallography of 1 and 3 revealed the presence of a twisted arrangement of the edged-shared bridging core unit. In agreement with the distorted nature of the twisted core, antiferromagnetic exchange interactions were observed between the vanadium(IV) centers of the dinuclear complexes with a superexchange mechanism operative. These results have been verified by DFT calculations. The complexes were also screened for their in vitro cytotoxicity against HeLa and HT-29 cancer cell lines. The results indicated that all the synthesized vanadium(IV) complexes (1-3) were cytotoxic in nature and were specific to a particular cell type. Complex 1 was found to be the most potent against HeLa cells (IC50 value 1.92 µM).

[Which patients from routine care use the new insulin analogue glargine U300 compared to patients with glargine U100 : A multicenter analysis of 14,123 patients with insulin glargine from die diabetes registries DPV and DIVE]. / Welche Patienten aus der Routinebetreuung verwenden das neue Insulin-Analogon Glargin U300 im Vergleich zu Patienten mit Glargin U100? : Eine multizentrische Analyse von 14.123 Patienten mit Insulin Glargin aus den Diabetesregistern DPV und DIVE.

BACKGROUND: Glargine U300 (Gla-300) is a further development of glargine U100 (Gla-100). Since 2015, Gla-300 has been available in Germany and Austria. We compared patients initiating therapy with Gla-300 with patients starting with Gla-100. Moreover, it was investigated whether patients from real-life diabetes care differ from patients participating in the EDITION clinical study program. METHODS: Data are based on the diabetes registries DPV and DIVE. Patients started/switched to Gla-100 or Gla-300 in 2015 were included. Linear regression was applied for bodyweight (BW), BMI, HbA1C, daily total and basal insulin dose/kgBW and negative binomial regression for severe hypoglycemia. Data were adjusted for age, sex, and diabetes duration. RESULTS: 14,123 patients were identified (Gla-100: 11,397; Gla-300: 2726). Gla-300 patients with T1D were older, T2D patients younger compared to subjects using Gla-100 (both p < 0.0001). In Gla-300 subjects, diabetes duration was longer (both p < 0.0001). Patients started/switched to Gla-300 had a higher BW, a higher BMI and a lower baseline HbA1C. The rate of severe hypoglycemia was comparable. Total and basal insulin doses/kgBW were higher in patients with Gla-300. DPV/DIVE subjects were older, had a lower BW, and were more frequently male compared to EDITION patients. HbA1C was higher in T1D patients from DPV/DIVE. CONCLUSION: Data from the diabetes registries DPV/DIVE indicate differences between Gla-300 and Gla-100 patients at the onset of insulin therapy. This analysis provides additional information to the EDITION clinical study program.

Atom-Economical Palladium Carbon-Catalyzed de Novo Synthesis of Trisubstituted Nicotinonitriles.

A de novo palladium carbon-catalyzed synthesis of trisubstituted nicotinonitriles from easily synthesized homopropagylic or homoallylic aromatic alcohols in the presence of nitriles has been explored. The mechanism proceeds with an interesting generation of a Pd(II)-C palladacycle followed by an oxidative aromatization to generate the pyridine core. The pyridine core is generated with a noteworthy C-C bond cleavage in the case of the substituted nitriles. The moderate yields and easy separation of the products lend a unique importance to this one-pot methodology.

Chemistry of Monomeric and Dinuclear Non-Oxido Vanadium(IV) and Oxidovanadium(V) Aroylazine Complexes: Exploring Solution Behavior.

A series of mononuclear non-oxido vanadium(IV) [V(IV)(L(1-4))2] (1-4), oxidoethoxido vanadium(V) [V(V)O(L(1-4))(OEt)] (5-8), and dinuclear µ-oxidodioxidodivanadium(V) [V(V)2O3(L(1))2] (9) complexes with tridentate aroylazine ligands are reported [H2L(1) = 2-furoylazine of 2-hydroxy-1-acetonaphthone, H2L(2) = 2-thiophenoylazine of 2-hydroxy-1-acetonaphthone, H2L(3) = 1-naphthoylazine of 2-hydroxy-1-acetonaphthone, H2L(4) = 3-hydroxy-2-naphthoylazine of 2-hydroxy-1-acetonaphthone]. The complexes are characterized by elemental analysis, by various spectroscopic techniques, and by single-crystal X-ray diffraction (for 2, 3, 5, 6, 8, and 9). The non-oxido V(IV) complexes (1-4) are quite stable in open air as well as in solution, and DFT calculations allow predicting EPR and UV-vis spectra and the electronic structure. The solution behavior of the [V(V)O(L(1-4))(OEt)] compounds (5-8) is studied confirming the formation of at least two different types of V(V) species in solution, monomeric corresponding to 5-8, and µ-oxidodioxidodivanadium [V(V)2O3(L(1-4))2] compounds. The µ-oxidodioxidodivanadium compound [V(V)2O3(L(1))2] (9), generated from the corresponding mononuclear complex [V(V)O(L(1))(OEt)] (5), is characterized in solution and in the solid state. The single-crystal X-ray diffraction analyses of the non-oxido vanadium(IV) compounds (2 and 3) show a N2O4 binding set and a trigonal prismatic geometry, and those of the V(V)O complexes 5, 6, and 8 and the µ-oxidodioxidodivanadium(V) (9) reveal that the metal center is in a distorted square pyramidal geometry with O4N binding sets. For the µ-oxidodioxidodivanadium species in equilibrium with 5-8 in CH2Cl2, no mixed-valence complexes are detected by chronocoulometric and EPR studies. However, upon progressive transfer of two electrons, two distinct monomeric V(IV)O species are detected and characterized by EPR spectroscopy and DFT calculations.

Crystal structure of catena-poly[[aquadi-n-propyl-tin(IV)]-µ-oxalato].

The title compound, [Sn(C3H7)2(H2O)(C2O4)] n , represents the first diorganotin(IV) oxalate hydrate to be structurally characterized. The tin(IV) atom of the one-dimensional coordination polymer is located on a twofold rotation axis and is coordinated by two chelating oxalate ligands with two slightly different Sn-O bond lengths of 2.290 (2) and 2.365 (2) Å, two symmetry-related n-propyl groups with a Sn-C bond lengths of 2.127 (3) Å, and a water mol-ecule with a Sn-O bond length of 2.262 (2) Å. The coordination polyhedron around the Sn(IV) atom is a slightly distorted penta-gonal bipyramid with a nearly linear axis between the trans-oriented n-propyl groups [C-Sn-C = 176.8 (1)°]. The bond angles between the oxygen atoms of the equatorial plane range from 70.48 (6)° to 76.12 (8)°. A one-dimensional coordination polymer results from the less asymmetric bilateral coordination of the centrosymmetric oxalate anion, inter-nally reflected by two slightly different C-O bond lengths of 1.248 (3) and 1.254 (3) Å. The chains of the polymer propagate parallel to [001] and are held together by hydrogen bonds between water mol-ecules and oxalate anions of neighboring chains, leading to a two-dimensional network parallel to (100).

catena-Poly[[di-tert-butyl-tin(IV)]-µ-oxalato].

The title compound, [Sn(C4H9)2(C2O4)] n , an unexpected side product in the reaction of di-tert-butyl-tin(IV) oxide with nitric acid, represents the first diorganotin(IV) oxalate to be structurally characterized. The Sn(IV) atom of the one-dimensional coordination polymer is located on a mirror plane and is coordinated by two chelating oxalate ions with two rather different Sn-O bond lengths of 2.150 (1) and 2.425 (1) Å, and two t-butyl groups with Sn-C bond lengths of 2.186 (2) and 2.190 (2) Å. The coordination polyhedron around the Sn(IV) atom is a distorted tetra-gonal disphenoid. The centrosymmetric oxalate ion also has an asymmetric coordination geometry, as reflected by the two slightly different C-O bond lengths of 1.242 (2) and 1.269 (2) Å. The chains of the polymer propagate along the b-axis direction. Only van der Waals inter-actions are observed between the chains.

Methyl-phospho-nic acid, CH3PO(OH)2.

The asymmetric unit of the title compound, CH5O3P, contains two independent mol-ecules with nearly identical bond lengths and angles. In the crystal, each of the mol-ecules acts as acceptor (P=O) and donor (P-OH) of four hydrogen bonds to three adjacent mol-ecules, resulting in the formation of two different bilayers (one for each mol-ecule) stacked perpendicular to the a axis in the crystal.

Dimeric ethyl-tin(IV)-dibromide-hydroxide-N,N-di-methyl-formamide.

Di-µ-hydroxido-bis-[di-bromido-(di-methyl-formamide-κO)ethyl-tin(IV)], [Sn2Br4(C2H5)2(OH)2(C3H7NO)2], was prepared from ethyl-tin(IV) bromide and N,N-di-methyl-formamide (DMF) in air. The crystal structure exhibits the typical structural features of dimeric Lewis-base-stabilized monoorganotin(IV)-dihalide-hydroxides, RSnHal2(OH), i.e. two octa-hedrally coordinated Sn atoms are linked together via two bridging hydroxide groups, resulting in a centrosymmetric four-membered rhomboid-like Sn-OH ring with acute angles at the Sn atom, obtuse angles at the O atoms and two different tin-oxygen bond lengths. With the shorter bond trans to the ethyl group, this observation underlines once more the so-called trans-strengthening effect in monoorganotin(IV) com-pounds with octa-hedrally coordinated Sn atoms. Differences and similarities in the bond lengths and angles in the four-membered Sn-OH rings have been worked out for the rings in dimeric diorganotin(IV)-halide-hydroxides, [R 2SnHal(OH)]2, and hydrates of dimeric tin(IV)-trihalide-hydroxide-aqua-hydrates, [SnHal3(OH)(H2O)]2·nH2O.

1,7-Dideaza-2'-deoxy-6-nitronebularine: a pyrrolo[2,3-b]pyridine nucleoside with an intramolecular hydrogen bond stabilizing the syn conformation.

The title compound [systematic name: 1-(2-deoxy-ß-D-erythro-pentofuranosyl)-4-nitro-1H-pyrrolo[2,3-b]pyridine], C12H13N3O5, forms an intramolecular hydrogen bond between the pyridine N atom as acceptor and the 5'-hydroxy group of the sugar residue as donor. Consequently, the N-glycosylic bond exhibits a syn conformation, with a χ torsion angle of 61.6 (2)°, and the pentofuranosyl residue adopts a C2'-endo envelope conformation (²E, S-type), with P = 162.1 (1)° and τm = 36.2 (1)°. The orientation of the exocyclic C4'-C5' bond is +sc (gauche, gauche), with a torsion angle γ = 49.1 (2)°. The title nucleoside forms an ordered and stacked three-dimensional network. The pyrrole ring of one layer faces the pyridine ring of an adjacent layer. Additionally, intermolecular O-H∙∙∙O and C-H∙∙∙O hydrogen bonds stabilize the crystal structure.

Redetermination of dipotassium trichlorido-stannate(II) chloride monohydrate.

The title compound, K(2)[SnCl(3)]Cl·H(2)O, is the prototype of some isostructural compounds of composition M(2)[SnX(3)]X·H(2)O (M = large monovalent cation; X = halogen). In comparison with a previous study based on photographic data [Kamenar & Grdenic (1962 ▶). J. Inorg. Nucl. Chem.24, 1039-1045], its crystal structure has now been redetermined using CCD-based data in order to gain more accurate values for bond lengths and angles within the [SnCl(3)](-) anion and to locate the H atoms. The [SnCl(3)](-) anion has a trigonal-pyramidal shape and exhibits crystallographic mirror symmetry. With the exception of the K(+) ion which is located on a general position, all other atoms are situated on crystallographic mirror planes. The coordination polyhedron of the cation may be described by means of nine atoms in the form of a monocapped square anti-prism with seven typical K-Cl/O distances and two additional atoms at considerably longer distances. The positions of the H atoms of the water mol-ecule (also lying on a crystallographic mirror plane) could be determined and confirm the existence of a bifurcated O-H⋯Cl hydrogen bond to neighbouring Cl atoms.

Hexa-µ2-acetato-hexa-n-butyl-hexa-µ3-oxido-tin(IV) toluene monosolvate.

The title compound, [Sn6(C4H9)6(CH3COO)6O6]·C7H8, has one half-toluene mol-ecule and one half-organotin mol-ecule in the asymmetric unit. The latter is situated about an inversion centre and belongs to the class of hexa-meric monoorganooxo-tin carboxyl-ates with a hexa-gonal prismatic or 'drum-like' motif of the central tin-oxygen core. Two Sn3O3 rings in a flat-chair conformation are linked via six Sn-O bonds and six bridging acetate groups. All Sn atoms have approximate octa-hedral coordination geometry. The Sn-O bonds which are trans to the alkyl group are significantly shorter than the others. One butyl group is disordered over two different sites, with occupancies of 0.9:0.1. Very large atomic displacement parameters of the toluene mol-ecule indicate an unresolvable disorder about the twofold axis.

Calcium hexa-kis(dihydrogen-phosphito)-stannate(IV), Ca[Sn(H2PO2)6], with some remarks on the so-called Ge2(H2PO2)6 structure type.

The title compound, Ca[Sn(H2PO2)6], was formed after a few days when tin(II) fluoride was allowed to react with phosphinic acid at ambient conditions. The structure consists of chains of Ca(2+) and Sn(4+) cations in octa-hedral sites with -3 symmetry bridged by bidentate hypophosphite anions. The chains are hexa-gonally close packed along [001]. The discovery of the compound and the successful structure refinement provides strong evidence that an isostructural compound, originally described as the mixed-valence compound, Ge2[H2PO2]6 [Weakley (1983 ▶). J. Chem. Soc. Pak. 5, 279-281], must be reformulated as Ca[Ge(H2PO2)6].