Volume 72, Issue 3

A new complex [C(NH 2 ) 3 ] 2 [Mn(N 3 ) 4 ], in which Mn II cations are alternatively bridged by double EE azide-bridges and the [Mn(N 3 ) 4 ] n 2− chains are separated by guanidinium cation bilayers, has been synthesized and characterized by single crystal X-ray diffraction, infrared (IR) spectroscopy, elemental analyses, and magnetic measurements. Magnetic susceptibility data indicate antiferromagnetic interaction among the Mn II ions.

Three new bioactive metabolites, 1,6-dihydroxy- 2-methyl-heptan-4-one ( 1 ), 4-hydroxy-1-(2-methyl-oxiranyl)- pentan-2-one ( 2 ), and 2-(2-hydroxy-propyl)-4-methylfuran- 3-carboxylic acid amide ( 3 ) were isolated from the terrestrial Streptomyces sp. isolate ANK245, along with the new microbial constituent p -vinylanisol ( 4a ) and the known metabolites p -vinyl-phenol ( 4b ) and phenethyl alcohol. Analysis of the nonpolar part of the extract by gas chromatography/mass spectrometry (GC-MS) provided further evidence for tetradecanoic acid, 9-octadecenoic acid, hexadecanoic acid, 2-methoxy-4-vinylphenol ( 4c ), 4-hydroxy-3-methoxy-benzaldehyde, o -hydroxybiphenyl, and 1,5,9-trimethyl-4,8,13-cyclotetradecatrien-1,3-diol ( 5 ). Structures 1–3 of the new compounds were elucidated by nuclear magnetic resonance (NMR) and NMR spectroscopy, but mass spectrometry (MS) techniques and their absolute configuration were determined by density functional theory (DFT) calculations and Mosher derivatisation. Their antimicrobial and cytotoxic activities were evaluated in comparison with the crude bacterial extract.

The hydrothermal reaction of 5,5′-[(pyridine-3,5-dicarbonyl)bis(azanediyl)]diisophthalic acid (H 4 L) with a Co(II) salt yields the new complex: [Co 3 (HL) 2 (H 2 O) 4 ] ( 1 ), which has been characterized by single crystal X-ray diffraction, IR, and elemental and thermogravimetric analyses. Complex 1 exhibits a binodal (4,8)-connected 2D net structure with (4 20 .6 8 )(4 6 ) 2 topology. The magnetic properties of 1 were also investigated.

The hydrothermal reaction of CdSO 4 with 2,5-di(1 H -imidazol-4-yl)thiophene (L) in the presence of ammonium hydroxide at 100°C gives rise to a new complex [Cd(L)(SO 4 )] n ( 1 ). Complex 1 has been characterized by single-crystal X-ray diffraction, IR spectroscopy, and elemental and thermogravimetric analyses. It crystallizes in the monoclinic system with the space group C 2/ c and shows a 2D network structure. Complex 1 can emit fluorescence.

In addition to amorphous material and Ba 7 [BO 3 ] 4− x F 2−3 x , air and moisture sensitive single crystals of Ba 7 [BO 3 ] 3 Br(O 1.33 F 1.33 ) were formed from H 3 BO 3 , Ba(OH) 2 , BaF 2 and BaBr 2 ·2 H 2 O in alumina crucibles open to the atmosphere at 1300 K for 13 h. Ba 7 [BO 3 ] 3 Br(O 1.33 F 1.33 ) crystallizes in the hexagonal space group P 6 3 mc (no. 186, Z =2) with the lattice parameters a =1118.1(2) and c =723.93(13) pm. The Raman spectrum of the title compounds was also acquired and is compared to literature data.

The detection of target molecules via luminescence changes of appropriate sensors is a powerful tool to determine the presence of analytes qualitatively and quantitatively. Therefore, the exploration of synthetic routes to new sensors is important to facilitate the recognition of a large range of analytes. In this report we describe such a new route to sensors and discuss the behavior of the synthesized sensors in the presence of different analytes. The prepared anthracene derivatives belong to two classes of substances. On the one hand imines were synthesized wherein the isomerization of their inherent carbon nitrogen double bond provides an effective non-radiative relaxation pathway. On the other hand amines were received by reduction of the mentioned imines. Their intramolecular charge transfer (ICT) based sensing mechanism allows the detection of protons in a reversible colorimetric fashion. Furthermore, the addition of zinc cations in the aprotic solvent DCM provides the first example showing that the detection of these colorimetric pH sensors is not limited to protons.

The cubic LaIrSi type has 23 representatives in aluminides, gallides, silicides, germanides, phosphides, and arsenides, all with a valence electron count of 16 or 17. The striking structural motif is a three-dimensional network of the transition metal ( T ) and p element ( X ) atoms with TX 3/3 respectively XT 3/3 coordination. Alkaline earth or rare earth atoms fill cavities within the polyanionic [ TX ] δ− networks. The present work presents a detailed theoretical study of chemical bonding in LaIrSi-type representatives, exemplarily for CaPtSi, BaIrP, BaAuGa, LaIrSi, CeRhSi, and CeIrSi. DFT-GGA-based electronic structure calculations show weakly metallic compounds with itinerant small magnitude DOSs at E F except for CeRhSi whose large Ce DOS at E F leads to a finite magnetization on Ce (0.73 μ B ) and induced small moments of opposite sign on Rh and Si in a ferromagnetic ground state. The chemical bonding analyses show dominant bonding within the [ TX ] δ− polyanionic networks. Charge transfer magnitudes were found in accordance with the course of the electronegativites of the chemical constituents.

Three novel mixed alkali borate-nitrates Na 3− x K x [B 6 O 10 ]NO 3 ( x =0.5, 0.6, 0.7) were synthesized hydrothermally; their crystal structures were determined through Rietveld analyses, and supported through EDX as well as vibrational spectroscopy. The phases represent solid solutions of the alkali borate-nitrate Na 3 (NO 3 )[B 6 O 10 ], which was reported in 2002 as a “New type of boron-oxygen framework in the Na 3 (NO 3 )[B 6 O 10 ] crystal structure” (O. V. Yakubovich, I. V. Perevoznikova, O. V. Dimitrova, V. S. Urusov, Dokl. Phys. 2002 , 47 , 791). Only two of the three crystallographically independent Na + positions in the new structures are partially substituted by K + ; a pure potassium borate-nitrate was not formed until now. The cell parameters of the novel phases vary from a =1261.72(5)–1267.12(5), b =1004.19(5)–1007.96(4), c =770.55(3)–774.38(3) pm, and V =0.97630(6)–0.98905(6) nm 3 in the orthorhombic space group Pnma (no. 62), in alignment with increasing K + content.

Solid-state reaction of Ca, CaCl 2 , Sr, SrCl 2 , C and BN at 900°C for 3 days yielded transparent red needles of Ca 2.57(4) Sr 0.43(4) Cl 2 [CBN] as minority product (<10%) mixed with crystals of isotypic yellow Ca 3 Cl 2 [CBN] and orange Sr 3 Cl 2 [CBN]. Ca 2.57(4) Sr 0.43(4) Cl 2 [CBN] crystallizes in the space group Pnma (no.62) with the unit cell parameters of a =1389.2(6), b =386.05(15) and c =1131.2(4)pm ( Z =4). The Raman spectrum confirms the presence of the [CBN] 4− unit. The incremental volume of the [CBN] 4− is calculated to be 50.7(10)Å 3 .