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Bis[N-benzyl-N-(2-phenylethyl)dithiocarbamato-κ2S,S′]lead(II)  [cached]
E. Sathiyaraj,S. Thirumaran,S. Selvanayagam
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812036161
Abstract: The molecule of the title compound, [Pb(C16H16NS2)2], is located on a twofold rotation axis, which runs through the PbII atom. The two dithiocarbamate ligands coordinate the metal in a pyramidal configuration through the S atoms. The two phenyl rings of each dithocarbamate ligand are aligned at a dihedral angle of 78.4 (1)°. The molecular conformation is stabilized by intramolecular C—H...S interactions.
Characterization and Determination of 2-(2-Phenylethyl)chromones in Agarwood by GC-MS  [PDF]
Wen-Li Mei,De-Lan Yang,Hao Wang,Jin-Ling Yang,Yan-Bo Zeng,Zhi-Kai Guo,Wen-Hua Dong,Wei Li,Hao-Fu Dai
Molecules , 2013, DOI: 10.3390/molecules181012324
Abstract: Agarwood is the fragrant resinous heartwood obtained from certain trees in the genus Aquilaria belonging to the family Thymelaeaceae. 2-(2-Phenylethyl)chromones and characteristic sesquiterpenes are the main classes of aromatic compounds isolated from agarwood. Although there are many sesquiterpenes, relatively few 2-(2-phenylethyl)chromones have been determined in agarwood by GC-MS. After analysis of the MS spectra of eighteen 2-(2-phenylethyl)chromone derivatives isolated from agarwood and identified by NMR spectroscopy, together with the reported MS data and characteristic of structures of 2-(2-phenylethyl)chromones, the MS characterization, fragmentation patterns and characteristic fragment peaks for the compounds were deduced and a table summarizing MS characterization of 2-(2-phenylethyl)chromones in agarwood is presented. All the 2-(2-phenylethyl)chromones previously reported in agarwood are substituted by methoxy or/and hydroxy groups, except for one compound. Due to the fact they all possess the same basic skeleton (molecular weight: 250) and similar substituent groups (methoxy or hydroxy groups), a formula (30m + 16n = MW ? 250) is provided to calculate the number of methoxy (m) or hydroxy (n) groups according to molecular ion peak or molecular weight (MW). We deduced that the characteristic fragmentation behaviors of the 2-(2-phenylethyl)chromones are the cleavages of the CH 2-CH 2 bond between chromone moiety and phenyl moiety. Thus, characteristic fragment ions, such as m/ z 91 [C 7H 7], 107 [C 7H 6+OH], 121 [C 7H 6+OCH 3], 137 [C 7H 5+OH+OCH 3] are formed by different substituted benzyl moieties, while characteristic fragment ions such as m/ z 160 [C 10H 8O 2], 176 [C 10H 7O 2+OH], 190 [C 10H 7O 2+OCH 3], 220 [C 10H 6O 2+OCH 3×2] are formed by different substituted chromone moieties. Furthermore, rules regarding to the relationship between the positions of hydroxy or methoxy groups and the relative abundances of benzyl and chromone fragment ions have been deduced. Elucidation of how the positions of hydroxy or methoxy groups affect the relative abundances of benzyl and chromone fragment peaks is also provided. Fifteen unidentified compounds of an artificial agarwood sample analyzed by GC-MS, were preliminary determined as 2-(2-phenylethyl)chromones by analysis of their MS characterization and by comparison of their MS spectra with those of 18 standard compounds or 2-(2-phenylethyl)chromones reported in literature according to the above-mentioned methods and rules. This report will be helpful for the analysis and structural elucidation of
Synthesis Characterization and Antibacterial, Antifungal Activity of N-(Benzyl Carbamoyl or Carbamothioyl)-2-hydroxy Substituted Benzamide and 2-Benzyl Amino-Substituted Benzoxazines  [PDF]
Tyson Belz,Saleh Ihmaid,Jasim Al-Rawi,Steve Petrovski
International Journal of Medicinal Chemistry , 2013, DOI: 10.1155/2013/436397
Abstract: New N-(benzyl carbamothioyl)-2-hydroxy substituted benzamides 13, 20, and 21 were synthesized using sodium bicarbonate and benzyl amine with 2-thioxo-substituted-1,3-benzoxazines 6, 10a, b, 11c, and 12a–n. The 2-thioxo-substituted-1,3-oxazines 6, 10a-b, 11d 12a–n, and 26 were converted to the corresponding 2-methylthio-substituted-1,3-oxazines 14a–l and 24 which were then converted to 2-benzyl amino-substituted-benzoxazines 15a–i by refluxing with benzylamine. Products 15a, b, e, f, and g were also synthesized by boiling the corresponding N-(benzyl carbamothioyl)-2-hydroxy substituted benzamides 13a, b, f, l, and m in acetic acid. 2-Oxo-substituted-1,3-benzoxazines 22 and 25 were prepared by treating the corresponding 2-methylthio-substituted-1,3-oxazines 14 and 24 with dilute HCl. The N-(benzyl carbamoyl)-2-hydroxy substituted benzamide 23 was synthesized from the reaction of 2-oxo-substituted-1,3-benzoxazine 22 with benzylamine. The new products were characterized using IR, 1H, and 13C NMR in addition to microanalysis. Selected compounds were tested in vitro for antibacterial and antifungi activity and the most active compounds were found to be the 4-(substituted-benzylamino)-2-hydroxy benzoic acids 9a and d (M. chlorophenolicum, MIC 50 and 25?μgm?L?1, resp.), N1, N3-bis (benzyl carbamothioyl)-4,6-dihydroxy-substituted phthalamides 20a and 20c (B. subtilis MIC 12.5, 50?μgm?L?1, resp.) and 21 (M. chlorophenolicum, MIC 50?μgm?L?1). 1. Introduction The search for new antibacterial compounds is a challenging task as bacteria are continuously developing resistance to antimicrobial compounds; however, infections due to such bacterial strains are infrequent although potentially fatal [1–3]. This ongoing problem has resulted in the search for newer, more effective antibacterial compounds [1–3]. Urea, thiourea 3 (X=O or S), and benzo-1,3-oxazine compounds 5 and 6 (Scheme 1) have been shown to possess antibacterial and antifungal properties [4–11]. The benzyl thiourea analogue 3 has been reported to show activity against Gram-positive bacteria [12]. Scheme 1: Previous synthesis of urea or thiourea 3 (X=O or S) and 2-amino benzo1,3-oxazine 5. The N-benzoyl-2-hydroxybenzamides [13] are important pharmacophores for antibacterial activity in which the 2-hydroxy group (hydrogen bonding donor) contributes to the activity, the imide linker (preferred) or urea linker retains activity and free NH is required for high activity. The Topliss method [14] was used in the optimization of salicylic acid derivatives for potential use as antibacterial agents. The employment and
Benzyl N′-benzhydrylidenehydrazinecarbodithioate  [cached]
Bing-Xiang Zhang
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808039408
Abstract: In the title molecule, C21H18N2S2, the C=N—N angle of 117.6 (2)° is significantly smaller than the ideal value of 120° expected for sp2-hybridized N atoms. This is probably a consequence of repulsion between the nitrogen lone pairs and the adjacent N atom, as suggested in Zheng, Qiu, Lin & Liu [Acta Cryst. (2006), E62, o1913–o1914]. The two neighbouring benzene rings form a dihedral angle of 75.95 (3)° with each other, while subtending dihedral angles of 84.18 (3) and 8.44 (2)° with the third ring in the structure.
Benzyl N-(4-pyridyl)carbamate
Hua Fang,Mei-Juan Fang,Yi-Ping Zhang
Acta Crystallographica Section E , 2010, DOI: 10.1107/s160053681000098x
Abstract: The title compound, C13H12N2O2, was obtained by the reaction of 4-aminopyridine and benzyl chloroformate in tetrahydrofuran. The crystal structure contains N—H...N hydrogen bonds between two unique molecules within layers and antiparallel C—O...O—C interactions [O...O = 3.06 (3) ] between the two molecules of the asymmetric unit.
N,N′-Bis(2-phenylethyl)naphthalene-1,8:4,5-bis(dicarboximide)  [cached]
Yuichiro Tsukada,Naoko Nishimura,Jin Mizuguchi
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536807060333
Abstract: The title compound, C30H22N2O4, is a derivative of the naphthalene–imide pigments that are characterized by significant overlap of the stacked molecules. The molecule has a centre of symmetry. Accordingly, the phenylethyl groups are arranged in a trans fashion across the skeleton. The phenyl rings are not parallel to the naphthaleneimide skeleton and are twisted in the same direction by 9.27 (7)°. The molecules are, however, stacked with insignificant overlap along the stacking axis, as characterized by appreciable slide in the direction of either the short or the long molecular axis, in marked contrast to the ordinary naphthalene–imide pigments.
Lan-Feng Hou,Yun Zhong,Yan Mei,Jun Fan
Acta Crystallographica Section E , 2009, DOI: 10.1107/s160053680904999x
Abstract: In the title compound, [Cu(C5H10NO2S2)2], the CuII cation is chelated by two bis(2-hydroxyethyl)dithiocarbamate anions with a distorted square-planar coordination geometry. Intermolecular O—H...O hydrogen bonding is observed between the terminal hydroxy groups in the crystal structure.
Kinetic study of benzyl sulfamide synthesis by thermolysis of N-(benzyl)-N′-(tert-butoxycarbolyl) sulfamide  [cached]
Luciana Gavernet,Maria Luisa Villalba,Luis Bruno Blanch,Ileana Daniela Lick
European Journal of Chemistry , 2013, DOI: 10.5155/eurjchem.4.1.44-48.717
Abstract: In this investigation, a kinetic study of the thermolysis of N-(benzyl)-N′-(tert-butoxycarbonyl) sulfamide to yield benzylsulfamide in an efficient manner was performed. The thermolysis reaction was monitored in helium flow by thermogravimetry at different heating rates between 0.2 and 10 oC/min. The activation energy value was obtained from the Kissinger-Akahira-Sunose isoconversional method and theoretical calculations (from Transition State Theory). The reaction model of the process was studied by means of the master-plot method. Results obtained from experiments of thermolysis performed under the melting point temperature of N-(benzyl)-N′-(tert-butoxycarbonyl) sulfamide fit with an Avrami-Erofeev model whereas data found for experiments at higher temperatures fit with first order model. Isothermal experiments were simulated at 115, 120 and 130 oC using the model-free method, employing only the activation energy value.
Qiu-Xia Zhang,Bi-Song Zhang
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808010453
Abstract: In the title compound, C14H13NO2, the mean planes through the benzyl and 2-hydoxybenzamide units make a dihedral angle of 68.81 (7)°. There is an intramolecular O—H...O hydrogen bond involving the carbonyl O atom and the 2-hydroxy substituent. In the crystal structure, N—H...O hydrogen bonds link symmetry-related molecules into one-dimensional chains extending along the a-axis direction. These chains are further connected via C—H...O hydrogen bonds, forming a sheet-like structure
Bis(1-benzyl-3-methylimidazolium-κC2)mercury(II) bis(hexafluoridophosphate)
Rosenani A. Haque,Abbas Washeel Salman,Madhukar Hemamalini,Hoong-Kun Fun
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811032235
Abstract: The asymmetric unit of the title complex, [Hg(C11H12N2)2](PF6)2, consists of one bis(1-benzyl-3-methylimidazolium)mercury(II) cation, one half of the cation and an additional HgII atom, which lies on an inversion centre, and three hexafluoridophosphate anions. The HgII atoms exist in a linear coordination geometry [C—Hg—C = 178.9 (2) and 180°] formed by two carbene C atoms from the imidazole rings. In the crystal, the cations and anions are connected via C—H...F hydrogen bonds, forming a three-dimensional network.
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