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Abstract: The paper studied factors of the gas phase (GP) ionic stabilization of molecular organic crystals of salts. The single crystal X-ray diffraction, electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) mass spectrometric (MS) methods are employed. The GP phenomena are explained by the comprehensive quantum-chemical theoretical models, providing significant information for the electronic structures and thermodynamics of the observed MS species. The n-chloro-alkyl aliphatic heterocyclic 5-sulfosalicylates i.e. 1-(2-chloroethyl) pyrrolidinium 5-sulfosalicylicilate (1), 1-(2-chloroethyl)-piperidinium 5-sulfosalicylicilate (2), and 1-(3-chloropropyl) piperidinium 5-sulfosalicylicilate (3) are examined. The ionic systems that contain N+H-heterocyclic fragments, a complex MS image variety of monocations, quaternary ammonium dications and hydrogen bonded molecular complexes revealed. Their stabilization is explained by proton transfer (PT), charge-transfer (CT) and Jahn–Teller (JT) effects. The 4-(2-chloroethyl) morpholinium hydrochloride crystals (4) yielded quaternary ammonium adduct which structure is crystallographically determined. In parallel the GP stabilized ions of 4 are analyzed. The complementary application of the single-crystal X-ray diffraction and MS methods provided unique structural evidences in condenses and in the GP able to understand the competitive intramolecular and environmental factors contributing to the thermodynamics stability of the ionic species. Therefore, the data reported are helped for more comprehensive knowledge of the basic mass spectrometric GP and phase transition phenomena with both its methodological development and used robust analytical technique application. [Copyright &y& Elsevier]

Abstract: The paper presented a comprehensive theoretical and experimental study on the molecular drugs-design, synthesis, isolation, physical spectroscopic and mass spectrometric elucidation of novel functionalization derivatives of Cytisine (Cyt), using nucleosidic residues. Since these alkaloids have established biochemical profile, related the binding affinity of the nicotinic acetylcholine receptors (nAChRs), particularly α7 sub-type, the presented correlation between the molecular structure and properties allowed to evaluated the highlights of the biochemical hypothesises related the Schizophrenia. The anticancer activity of α7 subtype agonists and the crucial role of the nucleoside-based medications in the cancer therapy provided opportunity for further study on the biochemical relationship between Schizophrenia and few kinds of cancers, which has been hypothesized recently. The physical electronic absorptions (EAs), circular dichroic (CD) and Raman spectroscopic (RS) properties as well as mass spectrometric (MS) data, obtained using electrospray ionization (ESI) and atmospheric-pressure chemical ionization (APCI) methods under the positive single (MS) and tandem (MS/MS) modes of operation are discussed. Taking into account reports on a fatal intoxication of Cyt, the presented data would be of interest in the field of forensic chemistry, through development of highly selective and sensitive analytical protocols. Quantum chemical method is used to predict the physical properties of the isolated alkaloids, their affinity to the receptor loop and gas-phase stabilized species, observed mass spectrometrically. [Copyright &y& Elsevier]

Mol­ecules of the title compound, C9H11NO, are connected into infinite chains by inter­molecular N—H⋯O hydrogen bonds of length 2.893 (3) Å between the N-methyl­amino and carbonyl functions. [ABSTRACT FROM AUTHOR]

Cations of the title compound, C3H9N2O+·C4HO4−·H2O, are connected by inter­molecular Nammonium—H⋯Oamide hydrogen bonds into helical chains propagating in the [010] direction. These chains are further linked by Nammonium—H⋯O hydrogen bonds to the hydrogensquarate anions, which in turn form O—H⋯O-bridged chains in the [100] direction, thereby giving rise to a three-dimensional network. The water O atoms participate in two O—H⋯O hydrogen bonds to the anions and one O⋯H—Namide bridge to the cation. [ABSTRACT FROM AUTHOR]

The title compound, 2C9H8NO2+·C4O42−, contains a dianion with approximately D4 h symmetry [C—C = 1.465 (4)–1.470 (4) Å and C—O = 1.248 (4)–1.264 (4) Å]. Individual dianions are linked to four neighbouring 8-hydroxy­quinolinium cations by O⋯H—N [2.666 (4) and 2.681 (4) Å] and O⋯H—O [2.596 (3) and 2.605 (3) Å] hydrogen bonds to generate a polymeric chain. [ABSTRACT FROM AUTHOR]

The title compound, 4-phenyl­pyridinium-3-squarate, C15H9NO3, exhibits an inter­planar angle between the pyridinium and squarate rings of 0.6 (1)°. It displays a dipolar electronic ground-state structure, with a positively charged pyridinium fragment and a negatively charged squarate moiety. In the mol­ecule, the two aromatic rings are twisted by 31.6 (1)°. The bond lengths within the squarate system represent average values for the two possible resonance structures, with a central typical carbon­yl bond [1.203 (2) Å] flanked by two longer `semicarbon­yl' bonds of lengths 1.228 (2) and 1.221 (2) Å. [ABSTRACT FROM AUTHOR]

Extracts of Chlorophora regia are frequently used in Ghana in traditional medicine. There is, however, no reported data on the chemical composition of the plant. Comprehensive phytochemical investigation of the stem bark of C. regia resulted in the isolation of three new prenylated 2-arylbenzofuran derivatives, regiafuran A–C ( 1–3 ), and one new prenylated flavonol ( 4 ), together with fifteen known compounds ( 5–19 ). Their structures were elucidated by combined spectroscopic analysis of their NMR and HRESI-MS n data. Compounds 1, 2, 5, 9 and 15 exhibited remarkable free radical scavenging properties with IC 50 values of 1.9 μg/ml, 2.4 μg/ml, 2.2 μg/ml, 2.1 μg/ml and 1.8 μg/ml, respectively, compared to the standard trolox (IC 50 1.1 μg/ml). The isolated compounds did not, however, show any anti-inflammatory potential when tested using a PGE 2 (prostaglandin E 2 ) competitive enzyme immunoassay. [ABSTRACT FROM AUTHOR]

Phytochemical investigation of the stem bark extract of Anopyxis klaineana was carried out by various chromatographic techniques resulting in the isolation and characterization of three new tirucallane triterpenoids, namely 3,23-dioxotirucalla-7,24-dien-21-oic acid ( 1 ), 3,4-secotirucalla-23-oxo-4(28)7,24-trien-3,21-dioic acid ( 2 ) and 3,4-secotirucalla-4-hydroxy-23-oxo-7,24-diene-3,21-dioic acid-21-methyl ester ( 3 ), along with nine known compounds ( 4–12 ). The structural elucidation of the compounds was performed by means of high-resolution mass spectrometry (HRMS n ), nuclear magnetic resonance (NMR), and by comparison to literature data. Although none of the isolated compounds showed antibacterial efficacy against selected environmental and clinically important pathogenic Gram-positive and -negative bacteria, they demonstrated moderate DPPH free radical scavenging properties. Furthermore, compounds 1 and 7 exhibited remarkable anti-inflammatory potential in a prostaglandin E 2 (PGE 2 ) competitive enzyme immunoassay with IC 50 values of 3.63 μM and 10.23 μM, respectively. [ABSTRACT FROM AUTHOR]

The chemical study of Erythrina livingstoniana has led to the isolation of three new flavanones namely 5,7,3′-trihydroxy-4′-methoxy-5′-formylflavanone (erylivingstone A) ( 1 ), 5,7,3′-trihydroxy-5′-(2-hydroxy-3-methylbut-3-enyl)-4′-methoxyflavanone (erylivingstone B) ( 2 ) and 5,7,3′-trihydroxy-5′-(3-hydroxy-3-methyl- trans -but-1-enyl)-4′-methoxyflavanone (erylivingstone C) ( 3 ) together with three known compounds ( 4 – 6 ). Their structures were elucidated on the basis of NMR data, HRMS n fragmentation pathway and by comparison with literature data. We evaluated the antibacterial efficacies and free-radical scavenging potential of the isolated compounds ( 1 – 6 ). The typical environmental strains of Gram-positive Bacillus subtilis , Gram-negative Escherichia coli , as well as against the clinically important Staphylococcus aureus , Streptococcus pyogenes and E. coli (risk-group 2) were used for the antibacterial assay. Compounds 5 and 6 exhibited the most pronounced efficacy against tested environmental bacteria as well as against the pathogenic strain of E. coli . Compound 3 was also quite active against these three bacterial strains. The isolated compounds showed weak radical scavenging properties with compound 6 being the most active, followed by compounds 2 , 3 and 5 . [ABSTRACT FROM AUTHOR]

Two new tirucallane-type triterpenoids were isolated from the bark of Entandrophragma congoënse (Meliaceae) along with five known compounds gladoral A, bipendensin, 4-hydroxymethyl-3,5-dimethyldihydrofuran-2(3 H )-one, scopoletin and 5,7-dimethoxy-6-hydroxycoumarin. Their structures were elucidated by means of spectroscopic analyses including 1D and 2D-NMR spectroscopy, high resolution mass spectrometric data as well as the comparison of data with those reported in the literature. The tested compounds ( 1 – 4 ) displayed moderated antiplasmodial activity against erythrocytic stages of chloroquine-resistant Plasmodium falciparum strain NF54 and low cytotoxicity on L6 cell lines. All the isolated compounds are reported for the first time from the genus Entandrophragma. [ABSTRACT FROM AUTHOR]

Bioassay guided fractionation of Hypericum riparium leaves extract has resulted in the isolation and characterization of three new compounds namely chipericumin E ( 1 ), hyperenone C ( 3 ), and hyperixanthone ( 5 ), together with twenty known compounds. Their structures were elucidated based on comprehensive interpretation of spectroscopic and spectrometric data. Compounds 1 – 4 , and 6 – 8 displayed moderate antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) and cytotoxic effects on the human gastric cell line BGC-823 with IC 50 values ranging from 6.54 to 18.50 μM. [ABSTRACT FROM AUTHOR]

The title compound, C20H19F3N2O4, crystallizes with two mol­ecules in the asymmetric unit. The important characteristics of the mol­ecule are the two C=N bonds in Z,E configuration, one in the β-methoxy-system and the other in the oxy­methyl side chain between the two aromatic rings. [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound, C20H19F3N2O4, contains one mol­ecule in the asymmetric unit. The CF3 group is disordered over two positions. The important characteristics of the mol­ecule are the two C=N bonds in an E,Z-configuration, viz. E in the β-methoxy system and Z in the oxymethyl chain between the two aromatic rings. [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound, C19H17F3N2O4, a metabolite of the fungicide trifloxy­strobin (TFS), contains one mol­ecule in the asymmetric unit. The CF3 group is disordered over two positions. The important characteristics of the mol­ecule are the two C=N bonds in an E,E configuration, one in the β-methoxy system and the other in the oxy­methyl side chain between the two aromatic rings. The mol­ecules are linked via an O—H⋯N hydrogen bond and an infinite spiral is formed along the b-axis direction. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, (4a R,5 R,6 S,7 S,8a S)-methyl 8a-ethenylocta­hydro-5-acet­oxy-7-{[2-(acetoxy­meth­yl)-1-oxo-2-propen­yl]­oxy}-α,4-bis­(methyl­ene)-3-oxo-1 H-2-benzopyran-6-acetate, C24H28O10, the mol­ecule has a cis configuration at the junction of the two six-membered rings and not a trans configuration as was assigned on the basis of NMR data in solution [Asaka et al. (1977). Phytochemistry, 16, 1838–1839]. [ABSTRACT FROM AUTHOR]