Volume 72, Issue 10

Five coordination complexes [Fe(ftpy) 2 ](ClO 4 ) 2 ·(H 2 O) 2 ( 1 ), [Cu(ftpy)(NO 3 )(H 2 O)](NO 3 ) ( 2 ), [Cu(ftpy) 2 ] 2 (ClO 4 ) 4 ·(C 2 H 5 OH) ( 3 ), [Zn(ftpy) 2 ]·(ClO 4 ) 2 ·(H 2 O) 1.5 ( 4 ) and [Cd(ftpy) 2 ] 2 (ClO 4 ) 4 ·(C 2 H 5 OH) ( 5 ) (ftpy=4′-(furan-2-yl)-2,2′:6′,2′-terpyridine) have been synthesized and characterized by IR, elemental analysis and single-crystal X-ray diffraction. With the exception of 4 , all complexes adopt normal homoleptic [M(ftpy) 2 ] 2+ motifs. In the crystal, both hydrogen bonds and face-to-face interactions between furyl and pyridyl rings facilitate the construction of three-dimensional networks. The DNA-binding activities of the five complexes have been investigated by fluorescence emission titration at room temperature suggesting an intercalative mode for 1–3 with a relative order, 3 > 2 > 1 , and a combined static and dynamic mode for 4 and 5 .

A new sesquiterpene lactone, namely colletotrin ( 1 ), together with two known fungal metabolites ( 2 , 3 ), was obtained from a rice culture of Colletotrichum gloeosporioides , an endophytic fungus isolated from the stem bark of Cameroonian medicinal plant Trichilia monadelpha (Meliaceae). The structure of the new compound was established on the basis of extensive NMR analysis ( 1 H, 13 C, heteronuclear single-quantum coherence and heteronuclear multiple-bond correlation) completed by high-resolution electrospray ionization mass spectroscopy results and by comparison of these data with those of related compounds described in the literature. Their cytotoxic and antibacterial activities against the mouse lymphoma L5178Y cell line and Mycobacterium tuberculosis , respectively, were also evaluated. This study is the first report on the isolation of fungal metabolites from endophytic fungi associated with T. monadelpha (Meliaceae).

A series of unexpected bis-coumarins have been synthesized by multicomponent reactions of 4-hydroxycoumarin, aldehydes, and cyclic secondary amines in ethanol at room temperature. The chemical structures of new compounds were identified by 1 H, 13 C NMR, and mass spectrometry. Furthermore, the molecular structure of the solid-state adduct of 3,3′-[(4-methoxyphenyl)-methylene]bis(4-hydroxy-2 H -chromen-2-one) with morpholine (1:1) has been confirmed by single-crystal X-ray diffraction. The cytotoxicity of the new coumarin derivatives against MCF7 breast cancer cells was evaluated. A docking study of the new products was carried out to assess the molecular affinity between the tested compound and Topoisomerase IIa.

In this work, new derivatives of the β -sitosterol scaffolds containing 1,2,3-triazole are prepared by the reaction of β -sitosterol with aromatic alkynes via copper(I)-catalyzed azide-alkyne cycloaddition reactions under microwave irradiation. The reaction has several advantages including high yields, short reaction times, and a simple work-up procedure.

Based on geometry optimization and magnetic structure investigations within density functional theory, a unique uranium nitride fluoride, isoelectronic with UO 2 , is shown to present peculiar differentiated physical properties. These specificities versus the oxide are related to the mixed anionic substructure and the layered-like tetragonal structure characterized by covalent-like [U 2 N 2 ] 2+ motifs interlayered by ionic-like [F 2 ] 2− ones and illustrated herein with electron localization function projections. Particularly, the ionocovalent chemical picture shows, based on overlap population analyses, stronger U–N bonding versus U–F and d (U–N)< d (U–F) distances. Further generalized gradient approximation+U calculations provide the ground state magnetic structure as insulating antiferromagnet with ±2 μ B magnetization per magnetic sub-cell and ~2 eV band gap.

C 6 F 5 SO 2 Cl reacts with organolithiums and organomagnesium halides RM (R=Me, Bu, Ph; M=Li, MgX) to give mainly C 6 F 5 H and C 6 F 5 Cl. C 6 F 5 SO 2 Br and PhMgBr form C 6 F 5 H and (C 6 F 5 S) 2 . This is in contrast to known transformations of them which yield exclusively C 6 F 5 SO 2 Nu under the action of O- and N-nucleophiles. Alternatively, C 6 F 5 SO 2 F is converted to C 6 F 5 SO 2 R and 4-BuC 6 F 4 SO 2 F or 2-PhC 6 F 4 SO 2 Ph under the same conditions. When R=Me, minor amounts of (C 6 F 5 SO 2 ) 2 CH 2 and 4-C 6 F 5 SO 2 CH 2 C 6 F 4 SO 2 F form in addition to C 6 F 5 SO 2 CH 3 .

Cadmium and lead(II) acesulfamate, Cd(C 4 H 4 NO 4 S) 2 ·2H 2 O and Pb(C 4 H 4 NO 4 S) 2 , were prepared by the reaction of acesulfamic acid and the respective metal carbonates in aqueous solution, and characterized by elemental analysis. Their crystal structures were determined by single crystal X-ray diffraction methods. The Cd(II) compound crystallizes in the monoclinic space group P 2 1 / c with Z =4 and the corresponding Pb(II) salt in the triclinic space group P 1̅ with Z =2. In both salts, acesulfamate acts both as a bi-dentate ligand through its nitrogen and carbonyl oxygen atoms and also as a mono-dentate ligand through this same oxygen atom, giving rise to polymeric structures; in the Pb(II) salt the ligand also binds the cation through its sulfoxido oxygen atoms. The FTIR spectra of the compounds were recorded and are briefly discussed. Some comparisons with other related acesulfamate and saccharinate complexes are made.

The diazaborole Me 3 Sn–B{N(Dipp)CH} 2 ( 1 ; B{N(Dipp)CH} 2 = N , N ′-bis(2,6-diisopropylphenyl)-2,3-dihydro- 1H -1,3,2-diazaborolyl) was prepared by the reaction of Me 3 SnCl with one equivalent of Li[B{N(Dipp)CH} 2 ]. Single crystals of 1 were obtained from hexane (triclinic space group P 1̅). The diazaborole 1 was mono-deprotonated at the heterocycle upon treatment with Li[Me] to give product 2 . In contrast to Li[B{N(Dipp)CH} 2 ] which reacted with P 4 to give the tetraphosphenediide Li 2 [{HC(Dipp)N} 2 B–P(1)P(2)P(3)P(4)–B{N(Dipp)CH} 2 ] ( 3 ; δ P =364.5, –29.4; 1 J P(2),P(3) =–509.8 Hz, 1 J P(1),P(2) =–434.3 Hz, 2 J P(1),P(3) =–3.7 Hz, 3 J P(1),P(4) =178.9 Hz) and the triphosphenide Li[{HC(Dipp)N} 2 B–PPP–B{N(Dipp)CH} 2 ] ( δ P =665.1, 175.4; 1 J P,P =500 Hz), the stannyl derivative 1 did not activate white phosphorus. The reaction of 1 with GaCl 3 yielded either Me 2 ClSn–B{N(Dipp)CH} 2 ( 4 ) or MeCl 2 Sn–B{N(Dipp)CH} 2 ( 5 ) depending on the molar ratio of the reactants. The monochlorinated diazaborole Me 2 ClSn–B{N(Dipp)CH} 2 was also obtained by the reaction of 1 with AsCl 3 .

The stannide Sm 2 Rh 3 Sn 5 was obtained by arc-melting of the elements and subsequent annealing at 1070 K in a silica tube. Sm 2 Rh 3 Sn 5 crystallizes with the orthorhombic Y 2 Rh 3 Sn 5 type structure, space group Cmc 2 1 , Z =4: a =444.46(8), b =2636.2(4), c =718.3(1) pm, wR =0.0711, 1761 F 2 values and 61 variables. The three crystallographically independent rhodium atoms show tricapped trigonal prismatic coordination by samarium and tin atoms. Sm 2 Rh 3 Sn 5 can be considered as a simple 1:1 intergrowth structure of TiNiSi- and NdRh 2 Sn 4 -related slabs of compositions SmRhSn and SmRh 2 Sn 4 . Temperature dependent magnetic susceptibility data revealed van Vleck type behavior caused by the proximity of the exited 6 H 7/2 state to the 6 H 5/2 ground state of Sm 3+ , and an antiferromagnetic ordering occurs at T N =3.5(5) K.

Treatment of hydrated ruthenium(III) chloride with tetra-2-pyridyl-1,4-pyrazine (tppz) in refluxing ethoxyethanol afforded the homoleptic dinuclear complex [(tppz)Ru( μ -tppz)Ru(tppz)] 4+ ( 1 ) besides small amounts of the species [Ru(tppz) 2 ] 2+ . The title complex 1 was obtained as purple crystals and characterized as its hexafluoridophosphate salt by NMR spectroscopy, mass spectrometry and microanalyses. The molecular structure of 1 (PF 6 ) 4 has been established by X-ray crystallography.