Triterpene glycosides from Antarctic sea cucumbers III. Structures of liouvillosides A(4) and A(5), two minor disulphated tetraosides containing 3-O-methylquinovose as terminal monosaccharide units from the sea cucumber Staurocucumis liouvillei (Vaney)

Two new minor triterpene glycosides, liouvillosides A(4) (1) and A(5) (2) have been isolated from the sea cucumber Staurocucumis liouvillei living in Antarctic and Sub-Antarctic waters. The structures of the new glycosides were elucidated using extensive nuclear magnetic resonance (NMR) spectroscopy ((1)H- and (13)C-NMR spectroscopy, (1)H-(1)H COSY, 1D-TOCSY, HMBC, HSQC and NOESY), ESI-MS and MALDI TOF MS. The glycosides 1 and 2 are disulphated tetraosides having very rare 3-O-methylquinovose as terminal monosaccharide.     

7-O-methylaloeresin A--a new chromone glycoside from Commiphora socotrana

A new 5-methylchromone glycoside, named 7-O-methylaloeresin A (2-acetonyl-8-C-beta-D[2'-O-(E)-4-hydroxycinnamoyl]glucopyranosyl-7- methoxy-5-methylchromone, 1), was isolated from Commiphora socotrana (Burseraceae). Its structure was elucidated by spectroscopic data (MS, UV, 1H- and 13C-NMR).     

Synthesis, Crystal Structure and Characterization of a New Mononuclear Zn(Ⅱ) Complex from Schiff-base Ligand

A new mononuclear [Zn(H-1L)2] (L = 1H-indole-3-ethylene-salicylaldimine) was synthesized through the reaction of Zn(Ac)2, salicylaldehyde and tryptamine in hot ethanol solution and characterized by X-ray crystal structure analysis. The crystal belongs to monoclinic, space group P21/n with a = 15.014(2), b = 10.857(1), c = 17.489(1) , β = 95.49(1)°, V = 2837.8(5) 3, Z = 4, Dc = 1.386 g/cm3, μ = 0.904 mm-1, F(000) = 1232, the final R = 0.0463 and wR = 0.0890 for 4990 independent reflections. In the complex, the Zn2+ ion presents a distorted N2O2 tetrahedral coordination involving two H-1L ligands.     

Preparation of highly potent and selective non-peptide antagonists of the arginine vasopressin V1A receptor by introduction of a 2-ethyl-1H-1-imidazolyl group

To find a new series of arginine vasopressin (AVP) V1A receptor antagonists, the influence of the 2-phenyl group of 2-phenyl-4'-[(2,3,4,5-tetrahydro-1H-1-benzazepin-1-yl)carbonyl]benzanilide (7) was investigated. Replacement of the 2-phenyl group by a 2-ethyl-1H-imidazol-1-yl group was effective in yielding a V1A-selective compound. Moreover, this imidazolyl group was introduced in the same position in YM-35471 (6), and further studies of these compounds were performed. Consequently, we found that the (Z)-4'-({4,4-difluoro-5-[(N-cyclopropylcarbamoyl)methylene]-2,3,4,5-tetrahydro-1H-1-benzazepin-1-yl}carbonyl)-2-(2-ethyl-1H-1-imidazol-1-yl)benzanilide (9f) exhibited highly potent affinity and selectivity, and was the most potent antagonist for the V1A receptor among our compounds. The synthesis and pharmacological evaluation of these compounds are described in this paper.     

Synthesis and Transformations of 2-R-5-Aryl-5,6-dihydro-7H-[1,2,4]-triazolo[5,1-b][1,3]thiazin-7-ones

A new procedure for preparation of 2-R-5-aryl-5,6-dihydro-7H-[1,2,4]triazolo[5,1-b][1,3]thiazin-7-ones by condensation of 5-R-1,2,4-triazole-3-thiones with 3-arylacryloyl chlorides was developed. The thiazine ring of the [1,2,4]triazolo[5,1-b][1,3]thiazin-7-ones is easily cleaved by treating with ammonia and hydrazine affording amides and hydrazides of 3-aryl-3-(1H-1,2,4-triazol-5-ylsulfanyl)propanoic acids. The latter react with isothiocyanates furnishing carbamoyl thiohydrazides of 3-aryl-3-(1H-1,2,4-triazol-5-ylsulfanyl)propanoic acids that in alkaline media undergo cyclization into 4-aryl-5-[2-(4H-1,2,4-triazol-5-ylsulfanyl)-2-phenylethyl]-2,4-dihydro-3H-1,2,4-triazole-5-thiones.     

A prenyloxycoumarin from Psiadia dentata

A new coumarin identified as 5-hydroxy-6-methoxy-7-(3-methyl-but-2-enyloxy)-2H-1-benzopyran-2-one (isoobtusitin) was isolated from Psiadia dentata. This compound showed, in vitro, a moderate inhibitory activity against poliovirus and a very weak activity against (HIV), whereas it was inactive against (HSV1), (VSV), and murine tumoral cell lines (3LL, L1210).     

叔丁基取代的环戊二烯基钛、锆、铪二氯化物的合成及催化乙烯聚合

(tBuC5H4 ) 2 MCl2 (M =Ti(1a) ,Zr(1b) ,Hf(1c) )和 (tBu2 C5H3 ) 2 MCl2 (M =Ti(2a) ,Zr(2b) ,Hf(2c) )可以通过单叔丁基环戊二烯基锂或双叔丁基环戊二烯基锂与MCl4 (M =Ti,Zr,Hf)在四氢呋喃中反应制备得到 ,用IR、1H NMR和EI MS对这些化合物进行了表征 .采用X光单晶结构分析测定了 (tBuC5H4 ) 2 HfCl2 的晶体结构 .六个化合物均具有一定的催化乙烯聚合活性     

Bisbenzopyrans and alkaloids from the roots of Stemona cochinchinensis

Two new bisbenzopyrans, namely 3,3'-bis(3,4-dihydro-4-hydroxy-6,8-dimethoxy-2H-1-benzopyran) (1), and 8'-methoxy-3,3'-bis(3,4-dihydro-4-hydroxy-6-methoxy-2H-1-benzopyran) (2), together with known 3,3'-bis(3,4-dihydro-4-hydroxy-6-methoxy-2H-1-benzopyran) (3), as well as three known pyrido[1,2-alpha]azapine alkaloids, stemokerrin (4), oxystemokerrin (5) and oxystemokerrin-N-oxide (6), were isolated and identified from the roots of Stemona cochinchinensis. The structures of these compounds were elucidated by 1D- and 2D-NMR spectra and other spectroscopic studies.     

Cycloaddition of benzoheteroazepine II Reactions and conformations of cycloadducts on1,5-benzothiazepines and 1,5-benzodiazepines with nitrile imine and nitrile oxides

Benzodiazepine and benzothiazepine derivatives have been well known as therapeutically important compounds. Four new tricyclic heterocyclic compounds, 3a,4,5,11-tetrahydro-3H-1,2,4-triazolo[4,3-d] [1, 5]benzothiazepines (3), 3a,4,5,11-tetrahydro-3H,6H-1,2,4-triazolo[4,3-d][1,5]benzodiazepine (4), 3a, 4,5,11-tetrahydro-1,2,4-oxadiazolo[4,5-d] [1,5]benzothiazepines (5, 6) and 3a,4,5,11-tetrahydro-6H-1, 2,4-oxadiazolo[4, 5-d] [ 1, 5 ] benzodiazepines (7,8), have been synthesized by 1,3-dipolar cycloaddition reactions of 2, 3-dihydro-1, 5-benzothiazepines and 2, 3-dihydro-1H-1, 5-benzodiazepine with benzonitrile N-phenylimine and benzonitrile oxides, respectively. The conformations of some cycloadducts and cycloaddition mechanism are described.     

Antigenotoxic ketosteroid from the red algae Jania adhaerens

A new ketosteroid, 6β,16β-dihydroxycholest-4-en-3-one (1), in addition to the known 6β-hydroxycholest-4-en-3-one (2), 6β-hydroxycholest-4,22-dien-3-one (3) and 16β-hydroxy-5α-cholestan-3,6-dione (4), was isolated from the red alga Jania adhaerens. The structures were assigned on the basis of (1)H- and (13)C-NMR experiments. The new compound (1) was evaluated for its genotoxic and cytotoxic activities and found to possess protective antigenotoxicity in human peripheral blood cells.     

Nonpeptide arginine vasopressin antagonists for both V1A and V2 receptors: synthesis and pharmacological properties of 4'-[5-(substituted methylidene)-2,3,4,5-tetrahydro-1H-1-ben zoazepine-1-carbonyl]benzanilide and 4'-[5-(substituted methyl)-2,3-dihydro-1H-1-benzoazepine-1- carbonyl]benzanilide derivatives

Arginine vasopressin (AVP) has a dual action, i.e. vasoconstriction and water reabsorption via V1A and V2 receptors, and may play a role in a number of diseases, including congestive heart failure (CHF), hypertension, renal disease, edema, and hyponatremia. We have attempted to develop a new series of AVP antagonists for both V1A and V2 receptors based on the hypothesis that the blockade of both V1A and V2 receptors might be beneficial to CHF patients. In this report, a series of compounds structurally related to 4'-[5-(substituted methylidene)-2,3,4,5-tetrahydro-1H-1-benzoazepine-1-carbonyl ]benzanilide (exo-olefin isomer) and 4'-[5-(substituted methyl)-2,3-dihydro-1H-1-benzoazepine-1-carbonyl]benzanilide (endo-olefin isomer) were synthesized and examined to have AVP antagonist activity for both V1A and V2 receptors. As a result, it was found that the (E)-exo-olefin isomers showed more potent binding affinity compared with endo-olefin isomers. Among these (E)-exo-olefin isomers, (E)-N-methyl-{1-[4-(2-methylbenzoylamino)benzoyl]-2,3,4,5-tetrahyd ro-1H-1 -benzoazepin-5-ylidene}acetamide (14) exhibited the most potent binding affinity and (E)-N-methyl-(1-{4-[2-(4-methylphenyl)benzoylamino]benzoyl}-2,3,4,5- tetrahydro-1H-1-benzoazepin-5-ylidene)acetamide (20) exhibited a high AVP antagonist activity for both V1A and V2 receptors after intravenous administration. Details of the synthesis and pharmacological properties of this series are presented.     

A new coumestan from Tephrosia calophylla

A new coumestan, tephcalostan (1) has been isolated from the whole plant of Tephrosia calophylla BEDD. together with two known flavonoids, 7-O-methylglabranin (2) and kaempferol 3-O-beta-D-glucopyranoside (3). The structure of tephcalostan was elucidated as 5'-(R)-8, 9-methylenedioxy-5'-isopropenyl-4', 5'-dihydrofurano[2', 3':2, 3]coumestan by extensive one-and two-dimensional (1D- and 2D-)-NMR techniques including (1)H-(1)H correlation spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond connectivity (HMBC) and nuclear Overhauser enhancement spectroscopy (NOESY) experiments.     

Daphwazirin, biscoumarin glycopyranoside from Daphne oleoides

Daphwazirin, a new biscoumarin glycoside (1), along with four known compounds (2), (3), (4) and (5) has been isolated from the roots of Daphne oleoides. Its chemical structure is established as 7-hydroxy-8-[2-oxo-2H-1-benzopyran-7'-(O-alpha-L-rhamnosyl)-6'-yl]-2H-1-benzopyran-2-one through spectroscopic techniques and chemical analysis.     

A Convenient Method to Obtain 4,5-Dihydro-1H-Methylpyrazoles by A Ring Transformation Reaction

A convenient method for the synthesis of alkyl[aryl]-substituted 5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-1-methylpyrazole (2) from a new ring transformation reaction of alkyl[aryl]-substituted-5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-1-pyrazolethiocarboxyamide (1) with methylhydrazine in THF, and the thermal dehydration of 2, are reported.     

Two new phenolic water-soluble constituents from branch bark of Davidia involucrata

Two new phenolic water-soluble constituents, involcranoside A (1) and involcranoside B (2) have been isolated along with five known phenolic compounds: 3,4-dimethoxyphenyl-O-beta-D-gluco-pyranoside (3), picein (4), and 1,4-dihydroxy-3-methoxy-phenyl-4-O-beta-D-glucopyranoside (5), leonuriside A (6) and 4-hydroxy-3-methoxybenzoic acid (7) from the branch bark of Davidia involucrata. Identification of their structures was achieved by 1D and 2D NMR experiments, including (1)H-(1)H COSY, NOESY, HMQC and HMBC methods and FAB mass spectral data.     

Synthesis of new bis-1,2,4-triazole derivatives

A series of new 1,2/1,3-bis[o-(N-methylidenamino-3-aryl-5-phenyl-4H-1,2,4-triazole-4-yl)phenoxy]ethane/propane derivatives 4 were prepared in good yields by treatment of 4-amino-3-aryl-5-phenyl-4H-1,2,4-triazoles 2 with certain bis-aldehydes 1.Compounds 4 were reduced with NaBH(4) to afford the corresponding 1,2/1,3-bis[o-(N-methylamino-3-aryl-5-phenyl-4H-1,2,4-triazole-4-yl)phenoxy]ethane/propane derivatives 5. All new compounds were characterized by IR, (1)H-NMR, (13)C-NMR and mass spectral data.     

3,7-Dimethylguanine, a new purine from a Philippine sponge Zyzzya fuliginosa.

A new purine 3,7-dimethylguanine (1) has been isolated from the marine sponge Zyzzya fuliginosa, along with the known metabolites, makaluvamines A, C, K (2--4), 4-hydroxyphenylacetic acid (5), methyl ester of 4-hydroxyphenylacetic acid (6), 4-hydroxyphenethyl alcohol (7), L-phenylalanine (8) and L-tryptophan (9). The structure of 3,7-dimethylguanine (1) was elucidated by analysis of 1D and 2D (one- and two-dimensional) NMR [HMQC (heteronuclear multiple quantum coherence), gHMBC (heteronuclear multiple bond connectivity), 1H-15N gHMBC] data, mass spectroscopy data, and by comparison with 3,7-dimethylisoguanine (10).     

A new cyclobutane lignan from Cinnamomum balansae

A new cyclobutane lignan, named cinbalansan (6), was isolated from the leaves of Cinnamomum balansae, along with five known compounds, 1,2-dimethoxy-4-(1-E-propenyl)benzene (1), 1,2-dimethoxy-4-(1-Z-propenyl)benzene (2), 1,2-dimethoxy-4-(2-propenyl)benzene (3), 3,4-dimethoxybenzaldehyde (4), and E-(3,4-dimethoxyphenyl)-2-propenal (5). The structure of cinbalansan was shown to be 1beta,2beta,3alpha,4alpha-1,2-dimethyl-3,4-bis(3,4-dimethoxyphenyl)cyclobutane by a combination of 1H-, 13C-NMR, and NOE- experiments and by direct analysis of the 1H-NMR spectrum by the method of X-application.     

Cation and anion diversity in [M(dithiooxalate)2]2- salts: structure robustness in crystal synthesis

A series of crystalline salts based on the [M(dto)2]2- (dto = 1,2-dithiooxalate, M = Ni, Pt, Cu) dianion with hydrogen-bond donor cations have been synthesised following a molecular tectonics approach. The chelating M(dto)[dot dot dot]HN supramolecular synthon has been exploited in a systematic study of its robustness. The effects of competition between hydrogen-bond acceptors, of the shape and functionality of the cations and of varying the metal in the anion are discussed. The preparation and structural characterisation of the new crystalline phases [4,4'-H(2)bipy][Pt(dto)2] (2), [HNC5H4CO2H-4]2[Pt(dto)2] (5), [HNC5H4CO2H-3]2[Pt(dto)2] (6), [HNC5H4CH2CO2H-4]2[Ni(dto)2] (7), [HNC(5)H(4)CH(2)CO(2)H-3]2[Ni(dto)2] (8), [HNC5H4CONH2-4]2[Ni(dto)2] (9), [HNC5H4CHNOH-4]2[Ni(dto)2] (10), [HNC5H4CHNOH-3]2[Ni(dto)2] (11), [4,4'-H2bipip][Ni(dto)2] (12), [H2NC5H9CO2H-4]2[Pt(dto)2] (12), [H2NC5H9CO2H-4]2[Cu(dto)2] (14), [H2NC5H9CO2H-3]2[Ni(dto)2][H2O]2 (15), [H2NC5H9CO2H-3]2[Pt(dto)2][H2O]2 (16), [H2NC5H9CO2H-3]2[Cu(dto)2][H2O]2 (17), [H(Me)NC5H9CO2H-4]2[Ni(dto)2][H2O]2 (18) is reported. The charge-assisted NH[dot dot dot]dto synthon is formed in each of compounds 1-20, and is apparently much more robust than the conventional synthons used (such as the carboxylic acid dimer), which have a much lower rate of occurrence. The NH[dot dot dot]dto synthon may be generalised to 3- and 4-pyridinium species and 3- and 4-piperidinium derivatives. In the latter cases branching of the hydrogen-bond networks through the NH2 groups arises. The robustness of the NH...dto synthon allows structures of the form [NH cation]2[M(dto)2] to be regarded as being formed by the packing of neutral supermolecules. Cases of isomorphism (as in 16-18) and latent polymorphism (e.g. in 4 and 6) are noted.     

Synthesis,Structure and Photoluminescence of a New Cadmium（Ⅱ） Complex Involving in situ Decarboxylation

A new luminescent dinuclear cluster complex [Cd2（pzc）2（AmTAZ）（HEO）4（NO3）]·NO3 （Hpzc = pyrazine-2-carboxylic acid, AmTAZ = 3-amino-4H-1,2,4-triazole） has been prepared by the assembly of Cdn with pyrazine-2,3-dicarboxylic acid and 3-amino-lH-1,2,4-triazole-5-car- boxylic acid ligands under hydrothermal conditions, in which in situ decarboxylation of H2pzdc and HAmTZC ligands simultaneously occurred, and HEpzdc was transformed into Hpzc while HAmTZC into AmTAZ. The crystal structure is of triclinic, space group P1 with a = 7.096（2）, b = 11.140（4）, c = 14.887（5）А, α= 92.641（4）, β= 91.348（6）, γ= 96.058（6）°, V = 1168.5（7）А^3, C12H18Cd2N10O14, Mr = 751.16, Z = 2, Dc = 2.126 g/cm^3, F（000） = 730,μ=1.910 mm^-1, R = 0.0320 and wR = 0.0998 for 4549 observed reflections （I 〉 2σ（I））. The dinuclear cluster of 1 is extended into a 3D supramolecular architecture through intermolecular hydrogen bonding interactions. Complex I exhibits strong blue photoluminescence at room temperature.