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1.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 4): o760, 2010 Mar 06.
Article in English | MEDLINE | ID: mdl-21580605

ABSTRACT

THE TITLE COMPOUND [SYSTEMATIC NAME: (3bS,5aS,7R,8R,10aR,10bS)-7-meth-oxy-10b-methyl-3b,4,5,6,7,8,9,10,10a,10b,11,12-dodeca-hydro-5a,8-methano-5aH-cyclo-hepta-l[5,6]naph-tho[2,1-b]furan-7-methanol], C(21)H(30)O(3), was isolated from the beans of Coffea robusta. The mol-ecule contains five fused rings including a furan ring. The two six-membered rings are in chair conformations, but the third six-membered ring and the five-membered aliphatic ring adopt envelope conformations. Inter-molecular O-H⋯O hydrogen bonding is present in the crystal structure.

2.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 8): o2176-7, 2010 Jul 31.
Article in English | MEDLINE | ID: mdl-21588456

ABSTRACT

In the title solvate, C(30)H(39)NO(5)·CH(4)O {systematic name: 21-acet-oxy-18,21-dihy-droxy-5,6,16,18-tetra-methyl-10-phenyl-6,7-ep-oxy-[11]cytochalasa-13,19-dien-1-one methanol solvate}, the organic mol-ecule exhibits the tetra-cyclic terpenoid skeleton of cytochalasin, consisting of fused five-, six-, three- and 11-membered rings. The five-membered ring adopts an envelope conformation, while the six-membered ring is in a boat conformation. The ep-oxy O atom on the six-membered ring is pointing away from the five-membered ring. An inter-stitial methanol solvent mol-ecule is hydrogen bonded to the cytochalasin mol-ecules and inter-molecular O-H⋯O and N-H⋯O hydrogen bonds connect the mol-ecules into infinite chains along the (10) direction.

3.
Nat Prod Res ; 23(10): 960-2, 2009.
Article in English | MEDLINE | ID: mdl-19521910

ABSTRACT

Lappaconitine is an important alkaloid of the aconite family and its biological activity is closely related to its structure. Through an X-ray structure analysis of hydrated lappaconitine hydrobromide, which was synthesised by us through a new method, the absolute configuration of lappaconitine was determined: monoclinic, P2(1), a = 10.619(2) A, b = 12.196(3) A, c = 12.282(2) A, beta = 90.87(1) degrees and Z = 2; Flack parameter is -0.0083(0.0046) and S = 0.867. Rings A, B, C, D, E and F, respectively, present boat, chair, envelope, boat, boat and envelope forms. The absolute stereo configuration of lappaconitine was determined as 1S, 4S, 5S, 7S, 8S, 9S, 10S, 11S, 13R, 14S, 16S and 17R.


Subject(s)
Aconitine/analogs & derivatives , Aconitine/chemistry , Crystallography, X-Ray , Molecular Structure , Stereoisomerism
4.
Angew Chem Int Ed Engl ; 48(19): 3499-502, 2009.
Article in English | MEDLINE | ID: mdl-19353611

ABSTRACT

Cluster's last stand: Six chiral reduced Schiff base ligands containing amino acids and seven La(III) ions self-assemble to form a novel heptameric lanthanum supramolecule with the aid of the CO(3)(2-) ion (see picture). The cluster exists as a single chiral triple helix. The CO(3)(2-) ion, which is derived from atmospheric CO(2) , adopts a rare mu(3)-tridentate bridging mode that links three La(III) ions, thus allowing the cluster to efficiently fix CO(2).

5.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): o1832, 2009 Jul 11.
Article in English | MEDLINE | ID: mdl-21583534

ABSTRACT

The title compound, C(20)H(30)O(2), is an ent-atisane diterpenoid which was isolated from the roots of Euphorbia kansuensis. The mol-ecule contains five six-membered rings, among which three six-membered rings of the bicyclo-[2.2.2]octane unit adopt boat conformations and two cyclo-hexane rings adopt chair conformations. In the crystal structure, mol-ecules are connected by inter-molecular O-H⋯O hydrogen bonds, forming zigzag chains propagating parallel to [001].

6.
Zhongguo Zhong Yao Za Zhi ; 33(12): 1415-7, 2008 Jun.
Article in Chinese | MEDLINE | ID: mdl-18837345

ABSTRACT

OBJECTIVE: To study the chemical constituents in the aerial part of Acalypha australis. METHOD: The aerial part of Acalypha australis were extracted with EtOH at room temperature. The compounds were separated by various kinds of chromatographic methods and their structures were identified on the basis of spectroscopic techniques. RESULT: Eleven compounds have been isolated and identified: emodin (1), beta-sitosterol (2), loliolide (3), 2,6-dimethoxy-1,4-benzoquinone (4), nicotinic acid (5), protocatechuic acid (6), daucosterol (7), gallic acid (8), rutin (9), succinic acid (10), brevifolin (11). CONCLUSION: Compounds 1, 3-5, 10 and 11 were obtained from A. australis for the first time.


Subject(s)
Euphorbiaceae/chemistry , Plant Components, Aerial/chemistry , Drugs, Chinese Herbal/chemistry , Ethanol/chemistry , Magnetic Resonance Spectroscopy , Organic Chemicals/analysis , Organic Chemicals/isolation & purification , Spectrometry, Mass, Electrospray Ionization
7.
J Inorg Biochem ; 102(11): 2026-34, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18838170

ABSTRACT

A new ligand, N,N'-dibenzylethane-1,2-diamine (L) and its four transition metal(II) complexes, ML(2)(OAc)(2).2H(2)O (M=Cu, Ni, Zn, Co), have been synthesized and characterized by elemental analysis, mass spectra, molar conductivity, NMR and IR. Moreover, the crystals structure of Cu(II) and Ni(II) complexes characterized by single crystal X-ray diffraction showed that the complexes have a similar molecular structure. Ni(II) has an regular octahedral coordination environment complexes, but typical Jahn Teller effect influenced Cu(II) in an elongated octahedral environment. The interaction between complexes and calf thymus DNA were studied by UV and fluorescence spectra measure, which showed that the binding mode of complexes with DNA is intercalation. Under physiological pH condition, the effects of Cu(OAc)(2)L(2).2H(2)O and Ni(OAc)(2)L(2).2H(2)O on human serum albumin were examined by fluorescence. The results of spectroscopic measurements suggested that the hydrophobic interaction is the predominant intermolecular force. The enthalpy change DeltaH(0) and the entropy change DeltaS(0) of Cu(OAc)(2)L(2).2H(2)O and Ni(OAc)(2)L(2).2H(2)O were calculated to be -11.533 kJ mol(-1) and 46.339 J mol(-1)K(-1), -11.026 kJ mol(-1) and 46.396 J mol(-1)K(-1), respectively, according to the Scatchard's equation. The quenching mechanism and the number of binding site (n approximately 1) were also obtained from fluorescence titration data.


Subject(s)
DNA/chemistry , Intercalating Agents/chemistry , Organometallic Compounds/chemistry , Serum Albumin/chemistry , Binding Sites , Cobalt/chemistry , Copper/chemistry , DNA/metabolism , Diamines/chemistry , Humans , Hydrogen-Ion Concentration , Intercalating Agents/metabolism , Kinetics , Ligands , Models, Molecular , Nickel/chemistry , Spectrometry, Fluorescence , Thermodynamics , Transition Elements/chemistry , X-Ray Diffraction , Zinc/chemistry
8.
J Nat Prod ; 71(1): 153-5, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18088099

ABSTRACT

Two new cucurbitacins, endecaphyllacins A (1) and B (2), together with six known analogues (3-8), were isolated from the tubers of Hemsleya endecaphylla. The structures of 1 and 2 were elucidated by NMR and MS spectroscopic analysis. The relative stereochemistry of 1 was determined by single-crystal X-ray diffraction. Compound 4 (cucurbitacin B) showed potent anti-HIV-1 in C8166 cells (EC=0.09 microg/mL) with a selectivity index of 16.7.


Subject(s)
Anti-HIV Agents/isolation & purification , Anti-HIV Agents/pharmacology , Cucurbitaceae/chemistry , Drugs, Chinese Herbal/isolation & purification , Drugs, Chinese Herbal/pharmacology , HIV-1/drug effects , Plants, Medicinal/chemistry , Triterpenes/isolation & purification , Triterpenes/pharmacology , Anti-HIV Agents/chemistry , Crystallography, X-Ray , Drugs, Chinese Herbal/chemistry , Molecular Structure , Plant Tubers/chemistry , Triterpenes/chemistry
9.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 9): o1765, 2008 Aug 16.
Article in English | MEDLINE | ID: mdl-21201747

ABSTRACT

THE TITLE COMPOUND (COMMON NAME: 3ß-acet-oxy-8-epi-sclareolide), C(18)H(28)O(4), is a sclareolide derivative, which was synthesized from 9(11)-en-3ß-acet-oxy-8-epi-sclareolide. In the mol-ecular structure, the two six-membered rings display chair conformations and the five-membered ring displays an envelope conformation. Weak inter-molecular C-H⋯O hydrogen bonding is present in the crystal structure.

10.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 8): o1621, 2008 Jul 31.
Article in English | MEDLINE | ID: mdl-21203311

ABSTRACT

The title compound, C(20)H(26)NO(2) (+)·Br(-), is an N-chiral quaternary ammonium salt synthesized from (2S*)-N-benzyl-N-methyl-tyrosine methyl ester. The dihedral angle between the phenyl ring and the benzene ring is 11.61 (19)°. In the crystal structure, the allyl group is disordered over two positions with site occupancy factors of ca 0.8 and 0.2. The bromide anion links to the quaternary ammonium cations via O-H⋯Br hydrogen bonding. An intramolecular O-H⋯Br hydrogen bond is also observed.

11.
Inorg Chem ; 45(10): 3941-8, 2006 May 15.
Article in English | MEDLINE | ID: mdl-16676952

ABSTRACT

Three novel metal-organic architectures, [Ag3(bta)].1.5H2O (1), [Cd3(bta)2(H2O)7].5H2O (2), and [Cu11(bta)6(Hbta)2(H2O)10].29H2O (3), were obtained by reactions of the corresponding metal salts with a flexible tripodal ligand, benzene-1,3,5-triacetic acid (H3bta), and their structures were determined by single-crystal X-ray diffraction studies. The results revealed that, in complexes 1 and 2, the carboxylate groups of the bta3- ligand adopted varied coordination modes to link metal atoms and further to form three-dimensional structures with open channels occupied by water molecules, while in complex 3, for the first time, the flexible H3bta acted as a secondary building unit to generate a novel nanometer-sized metallocage, which is composed of a Cu(II) paddle wheel (square secondary building units) and bta3-/Hbta2- organic links (triangular secondary building units). The photoluminescence properties of complexes 1 and 2 were investigated, and the results showed that 2 exhibited photoluminescence in the solid state at room temperature.


Subject(s)
Acetates/chemistry , Cadmium/chemistry , Copper/chemistry , Organometallic Compounds/chemistry , Silver/chemistry , Crystallography, X-Ray , Ligands , Luminescence , Models, Molecular , Molecular Conformation
12.
J Hazard Mater ; 129(1-3): 31-6, 2006 Feb 28.
Article in English | MEDLINE | ID: mdl-16298478

ABSTRACT

The new coordination polymer of sodium trinitrophloroglucinate, [Na(H2TNPG)(H2O)2]n, was synthesized by reacting trinitrophloroglucinol (H3TNPG) with NaHCO3 in aqueous solution and [Na(H2TNPG)(H2O)2]n was recrystallized to be yellow single crystal. The title compound was characterized by using elemental analysis and Fourier transform infrared (FT-IR) spectrum. Its crystal structure was determined by single crystal X-ray diffraction analysis. The crystalline belongs to monoclinic system and C2/c space group. Each Na+ ion is six-coordinated to one H2TNPG- anion and four water molecules in which the oxygen atoms in the water molecules act as bridging atoms. Coordination bonds, electrostatic interaction and intermolecular hydrogen bonds assemble the ions into network structures. The thermal decomposition mechanism of the complex was studied by using differential scanning calorimetry (DSC), thermogravimetry/derivative thermogravimetry (TG/DTG) and FT-IR techniques. Under nitrogen atmosphere with a heating rate of 10 degrees C/min the thermal decomposition of the complex contained one endothermic and five exothermic processes. Two intense exothermic decomposition processes were observed in the range of 173-228 degrees C suggesting its energetic nature and the solid decomposition residue at 500 degrees C was sodium isonitrile. Explosive properties revealed that the compound is sensitive to mechanical stimuli. All properties data observed show that the title compound has explosive properties and can act as components of ecologically clean initiating compositions.


Subject(s)
Crystallization , Hot Temperature , Nitro Compounds/chemistry , Phloroglucinol/analogs & derivatives , Calorimetry, Differential Scanning , Explosions , Molecular Structure , Phloroglucinol/chemistry , X-Ray Diffraction
13.
Acta Crystallogr C ; 60(Pt 10): m543-5, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15467135

ABSTRACT

The title compound, [Cu(2)(OH)(2)(C(12)H(8)N(2))(2)(H(2)O)(2)][Cu(C(10)H(9)NO(5)S)(2)].6H(2)O, is comprised of a copper-centred complex cation and a copper-centred complex anion; the cation lies about an inversion centre and in the anion the Cu atom lies on an inversion centre. In the doubly charged bridged dicopper cation, each Cu centre has distorted square-pyramidal geometry. In the square-planar dianion, two sulfonate ligands are trans coordinated to the Cu atom via a deprotonated hydroxyl O atom and an imine N atom, forming two six-membered chelate rings. The structure is stabilized by an extensive hydrogen-bond system and aromatic-ring stacking interactions.

14.
Pharmazie ; 59(7): 513-5, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15296086

ABSTRACT

The crystal structure of a cholor-bisabolene sesquiterpene has been determined for the absolute configuration. Its structure was elucidated as (-)-(1R,2R,3R,4R,6S,8S,10S)-chloro-2,10-diacetoxy-1,8-diangeloyloxy-3-hydroxy-11-methoxy-bisabol-7(14)-ene. The chlorine atom at C4 is axial in the cyclohexane ring. The molecule shows a stable chair conformation, and crystallizes in the monoclinic space group P2(1) with one molecule in the asymmetric unit.


Subject(s)
Hydrogen-Ion Concentration , Sesquiterpenes/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Bacteria/drug effects , Cell Line, Tumor , Crystallography, X-Ray , Drug Screening Assays, Antitumor , Humans , Microbial Sensitivity Tests , Models, Molecular , Molecular Conformation , Stereoisomerism , Structure-Activity Relationship
15.
Org Biomol Chem ; 1(6): 1080-5, 2003 Mar 21.
Article in English | MEDLINE | ID: mdl-12929651

ABSTRACT

An effective resolving agent, (2S, 3S)-di-O-(p-toluoyl) tartaric acid(4), was screened using a 'family' approach to yield direct resolution of (R)-terbutaline (1) with high optical purity and yield. Molecular recognition was studied by X-ray crystallographic analyses of the single crystals of the pair of diastereomeric salts. The more-soluble salt formed a sheet supramolecular structure, and the less-soluble salt formed a columnar supramolecular structure by enantiodifferentiating self-assembly. The water molecule plays an important role during optical resolution, and makes the supramolecular structure of the less-soluble salt more thermodynamically stable than that of the more-soluble salt. Solvent system has little influence on the resolution.

16.
Chemistry ; 9(16): 3965-73, 2003 Aug 18.
Article in English | MEDLINE | ID: mdl-12916123

ABSTRACT

Six noninterpenetrating organic-inorganic hybridized coordination complexes, [Mn(3)(2)(H(2)O)(2)](ClO(4))(2).2 H(2)O (5), [Mn(3)(2)(H(2)O)(2)](NO(3))(2) (6), [Mn(3)(2)(N(3))(2)].2 H(2)O (7), [Cu(3)(2)(H(2)O)(2)](ClO(4))(2) (8), [Mn(4)(2)(H(2)O)(SO(4))].CH(3)OH.5 H(2)O (9) and [Mn(4)(2)](ClO(4))(2) (10) were obtained through self-assembly of novel tripodal ligands, 1,3,5-tris(1-imidazolyl)benzene (3) and 1,3-bis(1-imidazolyl)-5-(imidazol-1-ylmethyl)benzene (4) with the corresponding metal salts, respectively. Their structures were determined by X-ray crystallography. The results of structural analysis of complexes 5, 6, 7, and 8 with rigid ligand 3 indicate that their structures are mainly dependant on the nature of the organic ligand and geometric need of the metal ions, but not influenced greatly by the anions and metal ions. While in complexes 9 and 10, which contain the flexible ligand 4, the counteranion plays an important role in the formation of the frameworks. Entirely different structures of complexes 5 and 10 indicate that the organic ligands greatly affect the structures of assemblies. Furthermore, in complexes 5 and 6, the counteranions located between the cationic layers can be exchanged by other anions. Reversible anion exchanges between complexes 5 and 6 without destruction of the frameworks demonstrate that 5 and 6 can act as cationic layered materials for anion exchange, as determined by IR spectroscopy, elemental analyses, and X-ray powder diffraction.

17.
Chemistry ; 9(11): 2611-5, 2003 Jun 06.
Article in English | MEDLINE | ID: mdl-12794904

ABSTRACT

An important synthon, tert-butanethiosulfinate (2), has been effectively resolved by forming molecular complexes with (R)-2,2'-dihydroxy-1,1'-binaphthyl (BINOL, 3) in high enantioselectivity (>99 % ee). The present procedure represents the first example of the resolution of thiosulfinate. The mechanism of chiral discrimination is discussed in terms of molecular recognition based on IR and Xray analyses of the diastereomeric complexes during the resolution. In the less-soluble complex, (R)-3 and (R)-2 self-assembled as a linear supramolecule; however, in the more-soluble complex, (R)-3 and (S)-2 formed a simple bimolecular complex by one stronger hydrogen bond. Hydrogen bonding is the major driving force for effective resolution.


Subject(s)
Naphthalenes/chemistry , Sulfonic Acids/chemistry , Crystallography , Hydrogen Bonding , Models, Molecular , Spectrophotometry, Infrared , Stereoisomerism
18.
J Org Chem ; 68(11): 4322-9, 2003 May 30.
Article in English | MEDLINE | ID: mdl-12762732

ABSTRACT

On the basis of the principle that the incorporation of the structurally rigid and conformationally restricted skeleton in beta-amino alcohols is beneficial to the enantioselective diethylzinc addition to imines, a series of chiral oxazolines, which had been designed and conveniently prepared from commercially available (1S,2S)-2-amino-1-phenylpropane-1,3-diol, were applied in the diethylzinc addition to diphenylphosphinoyl imines to give high yields of 68-84% and excellent ee values of 90-95%. The configuration of the product was controlled by the chirality of the carbon bonded to the hydroxyl group in the oxazoline. Oxazolines bearing a para- or meta-substituted phenyl group generally offered higher enantioselectivity than those containing an ortho-substituted phenyl. The X-ray structures of 4f and 4j, in combination with the proposed transition state, preliminarily explained why oxazolines with a para- or meta-substituent on the phenyl group gave higher enantioselectivities than those bearing an ortho-substituent. This successful example using chiral oxazolines to promote the titled reaction implies that a large family of chiral compounds containing an oxazoline ring moiety have the potential to be developed for promoting the highly enantioselective dialkylzinc addition to N-(diphenylphosphinoyl) imines.

19.
Chem Commun (Camb) ; (7): 880-1, 2003 Apr 07.
Article in English | MEDLINE | ID: mdl-12739658

ABSTRACT

[(CuimZnL-2H)(CuimZnL-H)](ClO4)3, the first imidazolate-bridged Cu(II)-Zn(II) complex of a unique single macrocyclic ligand with two flexible hydroxyethyl pendants, L (L = 3,6,9,16,19,22-hexaaza-6,19-bis(2-hydroxyethyl)tricyclo[22.2.2.2(11,14)]triaconta-1,11,13,24,27,29-hexaene) has been obtained, in which the macrocyclic ligand with two hydroxyethyl arms possesses a markedly different conformation compared to its dicopper analogue.

20.
Acta Crystallogr C ; 59(Pt 4): O219-20, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12682415

ABSTRACT

In the title compound, C(16)H(12)N(2)S(4), which is the result of the S-alkylation reaction of 2-mercaptobenzothiazole with ethylene dibromide, the planes of the two benzothiazole moieties form a dihedral angle of 3.84 (14) degrees. The bridging chain moiety, -SCH(2)CH(2)S-, adopts an antiperiplanar conformation. There are intermolecular S.S non-bonded contacts of 3.6471 (9) A, which stabilize the crystal packing.

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