Novel C3-Methylene-Bridged Indole Derivatives with and without Substituents at N1: The Influence of Substituents on Their Hemolytic, Cytoprotective, and Antimicrobial Activity.

Alkaloids are natural compounds useful as scaffolds for discovering new bioactive molecules. This study utilized alkaloid gramine to synthesize two groups of C3-substituted indole derivatives, which were either functionalized at N1 or not. The compounds were characterized by spectroscopic methods.

Synthesis, Structure and Biological Activity of Indole-Imidazole Complexes with ZnCl: Can Coordination Enhance the Functionality of Bioactive Ligands?

The ability of the indole-imidazole hybrid ligands to coordinate with the Zn(II) ion and the resulting structures of this new class of coordination compounds were analyzed in order to determine their structural properties and biological functionalities. For this purpose, six novel Zn(II) complexes, [Zn(InIm)Cl] (), [Zn(InMeIm)Cl] (), [Zn(IniPrIm)Cl] (), [Zn(InEtMeIm)Cl] (), [Zn(InPhIm)Cl] () and [Zn(InBzIm)Cl] () (where InIm is 3-((1H-imidazol-1-yl)methyl)-1H-indole), were synthesized by the reactions of ZnCl and the corresponding ligand in a 1:2 molar ratio in methanol solvent at an ambient temperature. The structural and spectral characterization of these complexes was performed using NMR, FT-IR and ESI-MS spectrometry and elemental analysis, and the crystal structures of - were determined using single-crystal X-ray diffraction.

Indole Derivatives Bearing Imidazole, Benzothiazole-2-Thione or Benzoxazole-2-Thione Moieties-Synthesis, Structure and Evaluation of Their Cytoprotective, Antioxidant, Antibacterial and Fungicidal Activities.

In the search for new bioactive compounds, a methodology based on combining two molecules with biological properties into a new hybrid molecule was used to design and synthesize of a series of ten indole derivatives bearing imidazole, benzothiazole-2-thione, or benzoxazole-2-thione moieties at the C-3 position. The compounds were spectroscopically characterized and tested for their antioxidant, antibacterial, and fungicidal activities. The crystal structures were determined for five of them.

Synthesis, antioxidant and cytoprotective activity evaluation of C-3 substituted indole derivatives.

A series of fifteen indole derivatives substituted at the C-3 position were synthesized and characterized. The antioxidant activity of all derivatives was investigated by three in vitro antioxidant assays, and the derivative with pyrrolidinedithiocarbamate moiety was the most active as a radical scavenger and Fe-Fe reducer. It can be stated that possible hydrogen and electron transfer mechanism is suggested for the quenching of the free radical.

Mononuclear gold(iii) complexes with diazanaphthalenes: the influence of the position of nitrogen atoms in the aromatic rings on the complex crystalline properties.

A series of mononuclear gold(iii) complexes of the general formula [AuCl(diazanaphthalene)], where diazanaphthalene is quinazoline (qz, 1), phthalazine (phtz, 2), 1,5-naphthyridine (1,5-naph, 3), 1,6-naphthyridine (1,6-naph, 4) or 1,8-naphthyridine (1,8-naph, 5), were prepared and fully characterized. The complexes 1-5 consist of discrete monomeric species with the Au(iii) cation in a square planar coordination geometry surrounded by three chloride anions and one diazanaphthalene ligand. Crystallographic studies indicate the presence of an extended 4 + 1 or 4 + 2 geometry around the square planar [AuCl(diazanaphthalene)] center due to Au⋯Cl and Au⋯N interactions.

Zinc(II) complexes with aromatic nitrogen-containing heterocycles as antifungal agents: Synergistic activity with clinically used drug nystatin.

Three novel Zn(II) complexes, [ZnCl(qz)] (1), [ZnCl(1,5-naph)] (2) and [ZnCl(4,7-phen)] (3), where qz is quinazoline, 1,5-naph is 1,5-naphthyridine and 4,7-phen is 4,7-phenanthroline, were synthesized by the reactions of ZnCl and the corresponding N-heterocyclic ligand in 1:2 molar ratio in ethanol at ambient temperature. The characterization of these complexes was done by NMR, IR and UV-Vis spectroscopy, and their crystal structures were determined by single-crystal X-ray diffraction analysis. Complexes 1 and 3 are mononuclear species, in which Zn(II) ion is tetrahedrally coordinated by two nitrogen atoms belonging to two qz or 4,7-phen ligands, respectively, and by two chloride anions, while complex 2 is a 1D coordination polymer that contains 1,5-naph as bridging ligand between two metal ions.

Hydrolysis of Methionine- and Histidine-Containing Peptides Promoted by Dinuclear Platinum(II) Complexes with Benzodiazines as Bridging Ligands: Influence of Ligand Structure on the Catalytic Ability of Platinum(II) Complexes.

Dinuclear platinum(II) complexes, [{Pt(en)Cl}(-qx)]Cl·2HO (), [{Pt(en)Cl}(-qz)](ClO) (), and [{Pt(en)Cl}(-phtz)]Cl·4HO (), were synthesized and characterized by different spectroscopic techniques. The crystal structure of was determined by single-crystal X-ray diffraction analysis, while the DFT M06-2X method was applied in order to optimize the structures of . The chlorido Pt(II) complexes were converted into the corresponding aqua species , and their reactions with an equimolar amount of Ac-L-Met-Gly and Ac-L-His-Gly dipeptides were studied by H NMR spectroscopy in the pH range 2.

One-step Access to Resorcinsalens-Solvent-Dependent Synthesis, Tautomerism, Self-sorting and Supramolecular Architectures of Chiral Polyimine Analogues of Resorcinarene.

Substituted 2,4- and 4,6-dihydroxyisophthalaldehydes were condensed with optically pure and racemic trans-1,2-diaminocyclohexane to form resorcinarene-like polyimine macrocycles (resorcinsalens), the structure and stoichiometry of which were controlled by the choice of the reaction medium. Particularly, the cyclocondensation reactions were driven by the solubility, tautomerization, or by social self-sorting. The resorcinsalens crystallized as inclusion compounds, in which the guest molecules were situated either in channels or in voids.

Mononuclear gold(III) complexes with phenanthroline ligands as efficient inhibitors of angiogenesis: A comparative study with auranofin and sunitinib.

Gold(III) complexes with 1,7- and 4,7-phenanthroline ligands, [AuCl(1,7-phen-κN7)] (1) and [AuCl(4,7-phen-κN4)] (2) were synthesized and structurally characterized by spectroscopic (NMR, IR and UV-vis) and single-crystal X-ray diffraction techniques. In these complexes, 1,7- and 4,7-phenanthrolines are monodentatedly coordinated to the Au(III) ion through the N7 and N4 nitrogen atoms, respectively. In comparison to the clinically relevant anti-angiogenic compounds auranofin and sunitinib, gold(III)-phenanthroline complexes showed from 1.

Benzhydryl Ethers of Tartaric Acid Derivatives: Stereochemical Response of a Dynamically Chiral Propeller.

The benzhydryl (diphenylmethyl) group is a molecular propeller that can act as a chirality reporter if it is introduced nearby a stereogenic center by making an ether bond. The hydrophobic character of the benzhydryl group allows transformation of insoluble natural tartaric acid derivatives into soluble entities in a nonpolar environment. Electronic circular dichroism spectra, recorded within the short-wavelength region of the phenyl B transitions (190-200 nm) shows strong bisignate Cotton effects.

Mononuclear gold(iii) complexes with l-histidine-containing dipeptides: tuning the structural and biological properties by variation of the N-terminal amino acid and counter anion.

Gold(iii) complexes with different l-histidine-containing dipeptides, [Au(Gly-l-His-N,N,N3)Cl]Cl·3HO (1a), [Au(Gly-l-His-N,N,N3)Cl]NO·1.25HO (1b), [Au(l-Ala-l-His-N,N,N3)Cl][AuCl]·HO (2a), [Au(l-Ala-l-His-N,N,N3)Cl]NO·2.5HO (2b), [Au(l-Val-l-His-N,N,N3)Cl]Cl·2HO (3), [Au(l-Leu-l-His-N,N,N3)Cl]Cl (4a) and [Au(l-Leu-l-His-N,N,N3)Cl][AuCl]·HO (4b), have been synthesized and structurally characterized by spectroscopic (H NMR, IR and UV-vis) and single-crystal X-ray diffraction techniques.

Antioxidant properties of thio-caffeine derivatives: Identification of the newly synthesized 8-[(pyrrolidin-1-ylcarbonothioyl)sulfanyl]caffeine as antioxidant and highly potent cytoprotective agent.

A series of nine thio-caffeine analogues were synthesized and characterised by NMR, FT-IR and MS spectroscopic methods. Molecular structures of four of them were determined using single crystal X-ray diffraction methods. The antioxidant properties of all compounds, at concentration ranges from 0.

Chalcogen analogues of nicotine lactam studied by NMR, FTIR, DFT and X-ray methods.

The selenoanalogue of nicotine has been synthesized and characterized by spectroscopic and X-ray diffraction methods. The crystals of selenonicotine are isomorphic with the thionicotine homologue and consist of molecules engaged in columnar π⋯π stacking interactions between antiparallely arranged pyridine moieties. These interactions, absent in other crystals containing nicotine fragments, seem to be induced by the presence of a lactam group.

Self-assembly of a covalent organic cage with exceptionally large and symmetrical interior cavity: the role of entropy of symmetry.

An exceptionally large size cuboctahedral imine cage is obtained from small size organic molecules in a thermodynamically driven [8+12] cyclocondensation. This is a demonstration of the role of entropy of symmetry as a driving force in reversible reactions.

Synthesis, spectral and solid state characterization of a new bioactive hydrazine bridged cyclic diphosphonium compound.

The facile preparation of a racemic hydrazine bridged diphosphonium compound possessing a ring system analogous to bicyclo[3.3.2]decane is reported.

Solution and solid-state effects on NMR chemical shifts in sesquiterpene lactones: NMR, X-ray, and theoretical methods.

Selected guaianolide type sesquiterpene lactones were studied combining solution and solid-state NMR spectroscopy with theoretical calculations of the chemical shifts in both environments and with the X-ray data. The experimental (1)H and (13)C chemical shifts in solution were successfully reproduced by theoretical calculations (with the GIAO method and DFT B3LYP 6-31++G**) after geometry optimization (DFT B3LYP 6-31 G**) in vacuum. The GIPAW method was used for calculations of solid-state (13)C chemical shifts.

Monocationic gold(III) Gly-L-His and L-Ala-L-His dipeptide complexes: crystal structures arising from solvent free and solvent-containing crystal formation and structural modifications tuned by counter-anions.

Monocationic gold(III) complexes with histidine-containing peptides, glycyl-L-histidine (Gly-L-His) and L-alanyl-L-histidine (L-Ala-L-His) have been synthesized and characterized by (1)H NMR spectroscopy and X-ray crystallography. The crystallized Au(III) complexes, [Au(Gly-L-His-N,N',N'')Cl]NO(3)·1.25H(2)O and [Au(L-Ala-L-His-N,N',N'')Cl]NO(3)·2.

Crystallographic evidence of Gly-D,L-Met oxidation to its sulfoxide in the presence of gold(III): solid solution of the racemic mixture of two diastereoisomers.

Crystallographic analysis of a solid solution of two diastereoisomers, i.e. ({(1S,R)-1-carboxy-3-[(R,S)-methylsulfinyl]propyl}aminocarbonyl)methanaminium tetrachloridoaurate(III) and ({(1S,R)-1-carboxy-3-[(S,R)-methylsulfinyl]propyl}aminocarbonyl)methanaminium tetrachloridoaurate(III), (C(7)H(15)N(2)O(4)S)[AuCl(4)], has shown that in the presence of gold(III), the methionine part of the Gly-D,L-Met dipeptide is oxidized to sulfoxide, and no coordination to the Au(III) cation through the S atom of the sulfoxide is observed.

Synthesis, conformation and chiroptical properties of diaryl esters of tartaric acid.

Previously unknown diaryl esters of l-tartaric acid have been synthesized. Their conformations have been studied by DFT calculations, NMR and circular dichroism spectroscopy in solution, as well as by X-ray diffraction in the crystalline state. The four-carbon tartrate chain of diaryl esters was found to be extended in all cases, with a higher degree of nonplanarity in the crystals.

Poly[[tetra-aquabis-(μ-hydroxy-acetato-κO,O:O,O)-μ(2)-sulfato-κO:O'-dicadmium(II)] monohydrate].

The title compound, {[Cd(2)(C(2)H(3)O(3))(2)(SO(4))(H(2)O)(4)]·H(2)O}(n), was obtained unintentionally in a transmetallation reaction. The crystal structure contains a two-dimensional metal-organic framework based on Cd(II)-(μ-hydroxy-acetato-κ(4)O(1),O(2):O(1),O(1'))-Cd(II) zigzag chains joined together by bridging SO(4) anions. The resulting layers are shifted with respect to each other and are stacked along the c axis.

Role of the gauche effect and local 1,3-dipole-dipole interactions in stabilizing an unusual conformation of tartarodinitriles.

This paper reports the synthesis, X-ray and NMR investigations of chiral and meso dinitriles of tartaric acid (tartarodinitriles) and their O,O'-diacetyl and O,O'-dibenzoyl derivatives. While in chiral tartaric acid its esters and NH amides the four-atom carbon chain is overwhelmingly trans, it is gauche in chiral tartarodinitriles. Conversely, meso-tartaric acid, its esters and amides display a tendency for the gauche conformation, but meso-tartarodinitriles usually have the trans conformation.

Coordination behaviour and two-dimensional-network formation in poly[[mu-aqua-diaqua(mu5-propane-1,3-diyldinitrilotetraacetato)dilithium(I)cobalt(II)] dihydrate]: the first example of an M(II)-1,3-pdta complex with a monovalent metal counter-ion.

The title compound, {[CoLi2(C11H14N2O8)(H2O)3].2H2O}n, constitutes the first example of a salt of the [M(II)(1,3-pdta)](2-) complex (1,3-pdta is propane-1,3-diyldinitrilotetraacetate) with a monopositive cation as counter-ion. Insertion of the Li+ cation could only be achieved through application of the ion-exchange column technique which, however, appeared unsuccessful with other alkali metals and the ammonium cation.

Synthesis and structural characteristics of lithocholate triads: steroid-type channels occupied by spacer fragments.

Reported in this paper are the syntheses and X-ray investigations of C(2) symmetrical molecular A-B-A triads consisting of two steroid units (lithocholic acid or its methyl ester) joined together by linkers derived from bifunctional molecules such as terephthalic acid or N,N'-dicarboxypiperazine. Unlike their monomeric analogues, some of these compounds form inclusion complexes. All steroidal triads form crystals that are highly pseudo-centrosymmetric, in which the constituting molecules are held together either exclusively by van der Waals forces or form lattice inclusion complexes, with guest molecules hydrogen bonded to the host.

Crystal engineering of analogous and homologous organic compounds: hydrogen bonding patterns in trimethoprim hydrogen phthalate and trimethoprim hydrogen adipate.

Background: Trimethoprim [2,4-diamino-5-(3',4',5'-trimethoxybenzyl)pyrimidine] is an antifolate drug. It selectively inhibits the bacterial dihydrofolate reductase (DHFR) enzyme.

Results: In the crystal structures of trimethoprim (TMP)-hydrogen phthalate (1) and trimethoprim-hydrogen adipate (2), one of the N atoms of the pyrimidine ring is protonated and it interacts with the deprotonated carboxylate oxygens through a pair of nearly parallel N-H.

Isostructuralism in a series of methylester/methylamide derivatives of (R,R)-O,O'-dibenzoyl tartaric acid; inclusion properties and guest-dependent homeotypism of the crystals of (R,R)-O,O'-dibenzoyltartaric acid diamide.

The compounds studied are methyl ester, amide and methylamide derivatives of (R,R)-O,O'-dibenzoyl tartaric acid. The molecules adopt the planar T conformation of the four-carbon chain with the terminal C=O bonds situated antiperiplanar with respect to the nearest C*-O bond. All investigated molecules occupy a twofold symmetry site in the crystal, including the mono(N-methylamide) monomethylester which lacks the C(2) molecular symmetry.