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Tetra-tert-butyl 13,14-dioxapentacyclo[8.2.1.14,7.02,9.03,8]tetradeca-5,11-diene-5,6,11,12-tetracarboxylate  [cached]
Alan J. Lough,Kelsey Jack,William Tam
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812039220
Abstract: The stereochemistry of the title compound, C32H44O10, at the cyclobutane ring is cis-anti-cis. The molecule lies across an inversion center. In the crystal, weak C—H...O hydrogen bonds connect molecules into chains along [100], forming R22(6) rings.
Tetramethyl 1,4-dimethyl-13,14-dioxapentacyclo[8.2.1.14,7.02,9.03,8]tetradeca-5,11-diene-5,6,11,12-tetracarboxylate  [cached]
Alan J. Lough,Kelsey Jack,William Tam
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812039219
Abstract: In the title compound, C22H24O14, the relative stereochemistry at the cyclobutane ring is cis-anti-cis and the methyl groups in the bicyclic rings are syn to each other. The two carboxylate groups attached to the same —C=C— bond are disordered over two sets of sites in a 0.603 (2):0.397 (2) ratio. In the crystal, weak C—H...O hydrogen bonds connect molecules into C(12) chains along [001] incorporating R222(10) rings.
Pentacyclo[8.2.1.14,7.02,9.03,8]tetradeca-5,11-diene  [cached]
Hsing-Yang Tsai,Ming-Hui Luo,Wei-Chi Lin,Che-Wei Chang
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812038780
Abstract: The title compound, C14H16, was prepared through [2 + 2] cycloaddition of norbornadiene. There are two independent molecules in the asymmetric unit: each is centrosymmetric with the centroid of the four-membered ring located about an inversion center. Each molecule possesses an exo–trans–exo conformation.
Spectroscopy of 13,14B via the one-neutron knockout reaction  [PDF]
V. Guimaraes,J. J. Kolata,D. Bazin,B. Blank,B. A. Brown,T. Glasmacher,P. G. Hansen,R. W. Ibbotson,D. Karnes,V. Maddalena,A. Navin,B. Pritychenko,B. M. Sherrill
Physics , 2000, DOI: 10.1103/PhysRevC.61.064609
Abstract: The single-nucleon knockout reactions 9Be(14B, 13B + gamma)X and 197Au(14B, 13B + gamma)X, at an incident energy of 60 MeV per nucleon, have been used to probe the structure of 14B and of the core fragment 13B. A dominant 2s configuration is deduced for the neutron in the ground state of 14B. The longitudinal momentum distribution for this state is consistent with "neutron halo" structure. Spin assignments for 13B excited states at 3.48 and 3.68 MeV are proposed based on the observed spectroscopic factors for one-neutron removal.
Antibacterial Activity of Phytochemicals Isolated from Atractylodes japonica against Methicillin-Resistant Staphylococcus aureus  [PDF]
Seung-Il Jeong,Seon-Young Kim,Sang-Jun Kim,Byung-Soon Hwang,Tae-Ho Kwon,Kang-Yeol Yu,Seung-Ho Hang,Koji Suzuki,Kang-Ju Kim
Molecules , 2010, DOI: 10.3390/molecules15107395
Abstract: Methicillin-resistant Staphylococcus aureus (MRSA) has been emerging worldwide as one of the most important problems in communities and hospitals. Therefore, new agents are needed to treat acute oral infections from MRSA. In this study, antibacterial compounds from the roots of Atractylodes japonica (A. japonica) were isolated and characterized. The compounds were isolated from the root extracts using HPLC-piloted activity-guided fractionations. Four A. japonica compounds were isolated and identified as atractylenolide III (1), atractylenolide I (2), diacetylatractylodiol [(6E,12E)-tetradeca-6,12-diene-8,10-diyne-1,3-diol diacetate, TDEYA, 3). and (6E,12E)-tetradecadiene-8,10-diyne-1,3-diol (TDEA, 4), which was obtained by hydrolysis of TDEYA. The minimum inhibitory concentrations (MICs) was determined in the setting of clinical MRSA isolates. Compound 4 showed anti-MRSA activity with a MIC value of 4-32 μg/mL. The overall results provide promising baseline information for the potential use of the extract of A. japonica as well as some of the isolated compounds in the treatment of bacterial infections.
Kinetic Determination of Paracetamol using a Novel Belousov-Zhabotinskii Oscillating System Catalyzed by a Tetraazamacrocyclic Complex
Gang Hu,Qin Wang,Min Meng,Ming Ying Lu,Fu Sheng Zhao,Lin Hu
Journal of Chemistry , 2012, DOI: 10.1155/2012/626982
Abstract: A new analytical method for determination of paracetamol is proposed. This method is based on a novel B-Z oscillating system, which involves a Tetraazamacrocyclic Complex [CuL](ClO4)2 as catalyst and malic acid as the substrate. The ligand L in the complex is 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene. By perturbation mount of paracetamol on the B-Z system, there is a linear relationship between the changes in the oscillation amplitude and the logarithm of paracetamol concentration in the range 5×10-7 to 2×10-4 M, with a correlation coefficient of 0.99743. The effects of influential variables, such as the concentration of reaction components, temperature and on the determinations were studied. The probable mechanism involving the perturbation of paracetamol on the oscillating chemical system was also discussed.
(meso-5,7,7,12,14,14-Hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene)copper(II) bis[O,O′-bis(4-methylphenyl) dithiophosphate]
Lin-Xin He,Li-Ke Zou,Bin Xie,Yang-Guang Xiang
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810009815
Abstract: The title compound, [Cu(C16H32N4)](C14H14O2PS2)2 or [Cu(trans[14]dien)][S2P(OC6H4Me-4)2]2, where trans[14]dien is meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene, was obtained by the reaction of [Cu(trans[14]dien)](ClO4)2 and [(C2H5)2NH]2 [S2P(OC6H4Me-4)2]2. The CuII atom lies on a centre of inversion and possesses a relatively undistorted square-planar coordination arrangement with four N atoms of the macrocyclic tetramine trans[14]dien [Cu—N = 1.9716 (19) and 2.0075 (19) ]. The two uncoordinated [(4-MeC6H4O)2PS2] groups act as counter-ions to balance the charge and interact with the [Cu(trans[14]dien)]2+ complex cation through N—H...S hydrogen bonds.
(5,7,7,12,14,14-Hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene)nickel(II) bis[O,O′-bis(4-tert-butylphenyl) dithiophosphate]
Chuan Lai,Bin Xie,Li-Ke Zou,Jian-Shen Feng
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536810049615
Abstract: The title salt, [Ni(C16H32N4)](C20H26O2PS2)2, comprises a centrosymmetric [Ni(Me6[14]dieneN4)]2+ dication (Me6[14]dieneN4 is 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene) and two O,O′-bis(4-tert-butylphenyl) dithiophosphate anions. The NiII ion lies on an inversion centre and displays a slightly distorted NiN4 square-planar chelation arrangement with four N atoms from the Me6[14]dieneN4 macrocycle. Two S atoms from symmetry-related anions are located in pseudo-axial positions with respect to the NiII ion, with Ni...S distances of 3.2991 (7) . Intermolecular N—H...S and C—H...S hydrogen bonds link the complex cation and pair of anions into a 1:2 type salt.
(meso-5,7,7,12,14,14-Hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene)nickel(II) bis[O,O′-bis(4-methylphenyl) dithiophosphate]
Bin Xie,Yang-Guang Xiang,Li-Ke Zou,Xiu-Li Chang
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809030955
Abstract: In the title compound, [Ni(C16H32N4)](C14H14O2PS2)2 or [Ni(trans[14]dien)][S2P(OC6H4Me-4)2]2, where trans[14]dien is meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene, the NiII ion lies across a centre of inversion and is four-coordinated in a relatively undistorted square-planar arrangement by the four N atoms of the macrocyclic ligand trans[14]dien. The two O,O′-di(4-methylphenyl)dithiophosphates act as counter-ions to balance the charge. Important geometric data include Ni—N = 1.9135 (16) and 1.9364 (15) .
Hexakis(2-aminopyridinium) di-μ6-oxido-tetra-μ3-oxido-tetradeca-μ2-oxido-octaoxidodecavanadium(V) dihydrate  [cached]
Caixia Yuan,Liping Lu,Miaoli Zhu,Qi Ma
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809004334
Abstract: In the title compound, (C5H7N2)6[V10O28]·2H2O, the [V10O28]6 anion is generated by crystallographic inversion symmetry and each of the five vanadium centres adopts a distorted VO6 octahedral geometry. In the crystal structure, a network of N—H...O, N—H...(O,O) and O—H...O hydrogen bonds helps to establish the packing.
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