A New Way to 2,3,4-Trisubstituted Benzo[h]quinolines: Synthesis, Consecutive Reactions and Cellular Activities †.

The reaction of mercaptoacetic acid esters with pentachloro-2-nitro-1,3-butadiene provides the appropriate precursors for the synthesis of 2,3,4-trisubstituted benzo[h]quinolines. These heterocycles are easily accessible via a single-step reaction with naphthalen-1-amine or anthracen-1-amine as the precursor. Due to the steric bulk and high electron density ring, the ring closure of benzo[h]quinolines takes place exclusively. Such highly substituted annelated pyridine systems can be modified in subsequent, selective reactions to build up new N-heterocycles with promising microbiological properties. The antibacterial and antiproliferative assays against four mammalian cell lines demonstrate that some of the sulfur-substituted benzo[h]quinoline analogs display potent phenotypic bioactivities in the single-digit micromolar range.

Surface Tuning of Wood via Covalent Modification of Its Lignocellulosic Biopolymers with Substituted Benzoates-A Study on Reactivity, Efficiency, and Durability.

Chemical modification of wood applying benzotriazolyl-activated carboxylic acids has proven to be a versatile method for the durable functionalization of its lignocellulosic biopolymers. Through this process, the material properties of wood can be influenced and specifically optimized. To check the scope and limitations of this modification method, various benzamide derivatives with electron-withdrawing (EWG) or electron-donating (EDG) functional groups in different positions of the aromatic ring were synthesized and applied for covalent modification of Scots pine (Pinus sylvestris L.) sapwood in this study. The bonded amounts of substances (up to 2.20 mmol) were compared with the reactivity constants of the Hammett equation, revealing a significant correlation between the modification efficiency and the theoretical reactivity constants of the corresponding aromatic substitution pattern. The successful covalent attachment of the respective substituted benzamides was proven by attenuated total reflection infrared (ATR-IR) spectroscopy, while the stability of the newly formed ester bond was proven in a standardized leaching test.

Crystal structure and Hirshfeld surface analysis of (µ-2-{4-[(carboxyl-atometh-yl)carbamo-yl]benz-amido}-acetato-κ2 O:O')bis-[bis-(1,10-phenanthroline-κ2 N,N')copper(II)] dinitrate N,N'-(1,4-phenyl-enedicarbon-yl)diglycine monosolvate octa-hydrate.

The centrosymmetric binuclear complex cation of the title compound, [Cu2(C12H10N2O6)(C12H8N2)4](NO3)2·C12H12N2O6·8H2O, is composed of a CuII atom with a distorted trigonal-bipyramidal coordination environment defined by four N atoms from two bidentate 1,10-phenanthroline ligands and one oxygen atom from one-half of the monodentate N,N'-(1,4-phenyl-enedicarbon-yl)diglycinate anion. The asymmetric unit is completed by one-half of the N,N'-(1,4-phenyl-enedicarbon-yl)diglycine solvent mol-ecule, which is located on a centre of inversion, by one nitrate counter-anion and four water mol-ecules. In the crystal, the cationic complexes are linked via inter-molecular π-π stacking and through lone-pair⋯π inter-actions involving the N,N'-(1,4-phenyl-enedicarbon-yl)diglycinate anion and the phenanthroline ligands. The N,N'-(1,4-phenyl-enedicarbon-yl)diglycine solvent mol-ecule is involved in classical and non-classical hydrogen-bonding inter-actions, as well as π-π stacking inter-actions. The centroid-to-centroid distances between aromatic entities are in the range 3.5402 (5)-4.3673 (4) Å. The crystal structure is stabilized by further C-H⋯O contacts as well as by O-H⋯O and N-H⋯O hydrogen bonds between water mol-ecules, the nitrate anions, the N,N'-(1,4-phenyl-enedicarbon-yl)diglycinate ligands, N,N'-(1,4-phenyl-enedicarbon-yl)diglycine solvent mol-ecules and phenanthroline ligands, giving rise to a supra-molecular framework. A Hirshfeld surface analysis was carried out to qu-antify these inter-actions.

Synthesis and characterization of propeller-shaped mono- to hexacationic quinolinium-substituted benzenes.

Diels-Alder reaction of 2-, 3- and 4-(phenylethynyl)quinolines and tetraphenylcyclopentadienone gave three regioisomeric 2,3,4,5,6-pentaphenyl-1-(quinolin-2-yl, -3-yl, and -4-yl)benzenes. Restricted rotation of the 3-yl and 4-yl substituted derivatives is observed between the central core and the substituents, resulting in propeller-shaped molecules. Likewise, 1,2-diquinolinyl-3,4,5,6-tetraphenylbenzenes with 3-yl,3-yl and 3-yl,4-yl connectivity were prepared. As evidenced by NMR spectroscopy, they form two diasteromers due to their restricted rotation. A cobalt-catalyzed [2 + 2 + 2]-cyclotrimerization of 2-(phenylethynyl)quinoline resulted in the formation of triphenyl-2,4,6- and -3,5,6-tri(quinolin-2-yl)benzenes. The same reaction was applied to 3,3'-ethyne-1,2-diyldiquinoline which formed hexa(quinolin-3-yl)benzene. N-Methylation gave the title compounds. Among those, the hexacationic hexa(N-methylquinolinio-3-yl)benzene is described. Stereochemical aspects are predominantly discussed by means of results of NMR experiments. DFT-calculations on the most stable conformations and the frontier orbital profiles of the hexacation as well as of its neutral precursor have been carried out.

Crystal structure of bis-[tris-(1,10-phenanthroline-κ(2) N,N')cobalt(II)] tetra-nitrate N,N'-(1,4-phenyl-enedicarbon-yl)diglycine solvate octa-hydrate.

The complex cation of the title compound, [Co(C12H8N2)3]2(NO3)4·C12H12N2O6·8H2O, contains a Co(II) atom with a distorted octa-hedral coordination environment defined by six N atoms from three bidentate 1,10-phenanthroline ligands. The asymmetric unit of the title compound is completed by one-half of the N,N'-(1,4-phenyl-enedicarbon-yl)diglycine solvent mol-ecule, which is located on a centre of inversion, by two nitrate counter-anions and four solvent water mol-ecules. Two [Co(C12H8N2)3](2+) cations are connected through C-H⋯O contacts and through lone-pair⋯π inter-actions involving the non-coordinating N,N'-(1,4-phenyl-enedicarbon-yl)diglycine and phenanthroline mol-ecules. The different aromatic ring systems are involved in π-π stacking and C-H⋯π inter-actions, with centroid-to-centroid distances in the range 3.7094 (8)-3.9973 (9) Å. The crystal structure is stabilized by further anion⋯π inter-actions and C-H⋯O contacts, as well as O-H⋯O and N-H⋯O hydrogen bonds between water mol-ecules, the non-coordinating nitrate anions, N,N'-(1,4-phenyl-enedicarbon-yl)diglycine and phenanthroline mol-ecules. These non-covalent inter-actions give rise to a three-dimensional supra-molecular network.

Crystal structure of catena-poly[[tetra-aqua-magnesium]-µ-(di-hydrogen hypodiphosphato)-κ(2) O:O'].

The crystal structure of the title compound, [Mg(H2P2O6)(H2O)4] n , is built up from (H2P2O6)(2-) anions bridging Mg(2+) cations into chains extending parallel to [011]. The Mg(2+) ion is located on an inversion centre and is octa-hedrally coordinated by the O atoms of two (H2P2O6)(2-) anions and four water mol-ecules. The centrosymmetric (H2P2O6)(2-) anion has a staggered conformation whereby the tetra-valent phospho-rus atom is surrounded tetra-hedrally by three O atoms and by one symmetry-related P atom. A three-dimensional O-H⋯O hydrogen-bonded network of medium strength involving the P-OH group of the anion and the water mol-ecules is present.

Chemistry of polyhalogenated nitrobutadienes, 14: Efficient synthesis of functionalized (Z)-2-allylidenethiazolidin-4-ones.

The reaction of mercaptoacetic acid esters with pentachloro-2-nitro-1,3-butadiene (1) provides an appropriate precursor for the synthesis of special thiazolidin-4-ones. Applying different anilines as the second constituent for the requisite cyclization step, a series of (Z)-2-allylidenethiazolidin-4-ones was obtained in yields up to 81%. Some subsequent reactions have been examined too, such as the formation of perfunctionalized 1H-pyrazoles upon treatment with hydrazine. Thiazolidinones are as well known for their physiological activities as for their application in optoelectronics.

Bis[bis-(2,2'-bi-pyridine-κ(2) N,N')(carbon-ato-κ(2) O,O')cobalt(III)] 2-{4-[(carboxyl-atometh-yl)carbamo-yl]benz-amido}-acetate hexa-hydrate.

The complex cation of the title compound, [Co(CO3)(C10H8N2)2]2(C12H10N2O6)·6H2O, contains a Co(III) atom with a distorted octa-hedral coordination environment formed by four N atoms from two bidentate 2,2'-bi-pyridine ligands and one bidentate carbonate anion. The asymmetric unit is completed by one-half of the 2-({4-[(carboxyl-atometh-yl)carbamo-yl]phen-yl}formamido)-acetate dianion, which is located on a centre of inversion, and by three water mol-ecules. Two [Co(CO3)(C10H8N2)2](+) cations are connected through C-H⋯O contacts by the uncoordinating anions. The aromatic rings of the 2,2'-bi-pyridine ligands and di-acetate anions are involved in π-π stacking and C-H⋯π inter-actions. The centroid-centroid distances are in the range 3.4898 (4)-3.6384 (5) Å. The crystal structure is stabilized by further O-H⋯O and N-H⋯O hydrogen bonds, which give rise to a three-dimensional supra-molecular network.

Hexa-aqua-nickel(II) di-hydrogen hypodiphosphate.

The asymmetric unit of the title compound, [Ni(H2O)6](H2P2O6), contains one-half of the hexa-aqua-nickel(II) cation and one-half of the di-hydrogen hypodiphosphate anion. In the complex cation, the Ni(2+) atom is located on an inversion center and has an octa-hedral coordination sphere. The P-P distance in the centrosymmetric anion is 2.1853 (7) Å. In the crystal, discrete [Ni(H2O)6](2+) cations and (H2P2O6)(2-) anions are stacked in columns parallel to the c axis and are linked into a three-dimensional network by medium-strength O-H⋯O hydrogen bonds.

µ-Hexa-thio-metadiphosphato-bis-[(1,4,7,10,13,16-hexa-oxa-cyclo-octa-decane-κ(6) O)rubidium] aceto-nitrile disolvate.

The asymmetric unit of the title compound, [Rb2(P2S6)(C12H24O6)2]·2CH3CN, contains one half of an [Rb(18-crown-6)2]2[P2S6] unit and one aceto-nitrile solvent mol-ecule. The [Rb(18-crown-6)]2[P2S6] unit is completed by inversion symmetry. Its Rb(+) ion is situated near the centre of the macrocyclic cavity, but is displaced by 0.8972 (1) Šfrom the O atoms of the crown in the direction of the [P2S6](2-) moiety. The overall coordination number of the cation is eight, defined by the six crown ether O atoms and by two terminal S atoms of the [P2S6](2-) anion. The hexa-thio-metadiphosphate anion is built up from two tetra-hedral PS4 units joined together by a common edge. The crystal structure is characterized by alternating layers of [Rb(18-crown-6)]2[P2S6] and aceto-nitrile solvent mol-ecules stacked along [010].

Ethane-1,2-diaminium 2,2'-[tereph-thal-oyl-bis(aza-nedi-yl)]di-acetate tetrahydrate.

In the title salt hydrate, C2H10N2 (2+)·C12H10N2O6 (2-)·4H2O, each of the ions is located about a centre of inversion and the asymmetric unit is completed by two water molecules in general positons. In the crystal, the cations, anions and water mol-ecules are connected by O-H⋯O and N-H⋯O hydrogen bonding into a three-dimensional network.

Calcium disodium hexa-thio-diphosphate(IV) octa-hydrate.

Single crystals of the title compound, CaNa(2)(P(2)S(6))·8H(2)O, were obtained by adding calcium hydroxide to an aqueous solution of Na(4)(P(2)S(6))·6H(2)O. The structure is isotypic with that of its strontium analogue and consists of one Ca(2+) cation, two Na(+) cations, one-half of a centrosymmetric (P(2)S(6))(4-) anion with staggered confirmation and four water mol-ecules in the asymmetric unit. The crystal structure can be described as being built up from layers of cations and anions extending parallel to (101). Within a layer, each CaO(8) polyhedron is connected via edge-sharing to two NaO(4)S(2) octa-hedra and to one NaO(2)S(4) octa-edron. The NaO(4)S(2) octa-hedra are, in turn, linked with two (P(2)S(6))(4-) anions through common corners. Various O-H⋯S hydrogen-bonding inter-actions lead to cohesion of adjacent layers. The Ca(2+) and one Na(+) cation are situated on a twofold rotation axis and the second Na(+) cation is situated on an inversion centre.

Strontium disodium hexa-thio-diphosphate(IV) octa-hydrate.

The crystal structure of SrNa(2)(P(2)S(6))·8H(2)O is isotypic with that of its calcium analogue. The asymmetric unit consists of one Sr(2+) cation (2 symmetry), two Na(+) cations (2 and symmetry, respectively), one-half of a centrosymmetric (P(2)S(6))(4-) anion with a staggered confirmation and four water mol-ecules. The crystal structure is built up from layers of cations and anions extending parallel to (101). Each SrO(8) polyhedron is connected via edge-sharing to two NaO(4)S(2) octa-hedra and to one NaO(2)S(4) octa-hedron. The NaO(4)S(2) octa-edra are, in turn, connected with two (P(2)S(6))(4-) anions through common corners. Adjacent layers are held together by several O-H⋯S hydrogen-bonding inter-actions.

Translation of pseudo-cross-conjugation into chemistry: cycloadditions of mesomeric betaines to the new ring system spiro[indazole-3,3'-pyrrole].

Indazolium-3-amidates (X-ray analysis), readily available on trapping the N-heterocyclic carbene indazol-3-ylidene with isocyanates, underwent [3+2]-cycloadditions with activated triple bonds to spiro[indazole-3,3'-pyrroles]. A combination of NMR techniques such as heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond correlation (HMBC), nuclear Overhauser enhancement spectroscopy (NOESY), and 1H/15N correlations were applied to elucidate the structures of the cycloadducts.