- Structures of nine oxygenated 4-methylene sterols from Hachijo marine sponge Theonella swinhoei
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Nine new sterols have been isolated from a marine sponge, Theonella swinhoei.Of these, seven sterols were found to be conicasterol derivatives oxygenated at carbon-7 and/or carbon-15.The other two were (24R)-7β,8β-epoxy-14α-methoxy-4-methylene-24-methylcholestan-3β-ol and (24R)-8,14-seco-8,14-dioxo-4-methylene-24-methylcholestan-3β-ol. - Keywords: marine sterol; 4-methylene sterol; conicasterol derivatives; Theonella swinhoei; marine sponge
- Sugo, Yumi,Inouye, Yoshinobu,Nakayama, Noboru
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- Sphingolipids from Conyza canadensis.
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Sphingolipid 1 and its corresponding beta-D-glucopyranoside derivative 2 have been isolated from the ethylacetate fraction of Conyza canadensis along with beta-sitosterol 3, stigmasterol 4, beta-sitosterol 3-O-beta-D-glucoside 5 and harmine 6, reported fo
- Mukhtar, Naveen,Iqbal, Kiran,Anis, Itrat,Malik, Abdul
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- Sterically hindered (pyridyl)benzamidine palladium(II) complexes: Syntheses, structural studies, and applications as catalysts in the methoxycarbonylation of olefins
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Reactions of ligands (E)-N′-(2,6-diisopropylphenyl)-N-(4-methylpyridin-2-yl)benzimidamide (L1), (E)-N′-(2,6-diisopropylphenyl)-N-(6-methylpyridin-2-yl)benzimidamide (L2), (E)-N′-(2,6-dimethylphenyl)-N-(6-methylpyridin-2-yl)benzimidamide (L3), (E)-N′-(2,6-dimethylphenyl)-N-(4-methylpyridin-2-yl)benzimidamide (L4), and (E)-N-(6-methylpyridin-2-yl)-N′-phenylbenzimidamide (L5) with [Pd(NCMe)2Cl2] furnished the corresponding palladium(II) precatalysts (Pd1–Pd5), in good yields. Molecular structures of Pd2 and Pd3 revealed that the ligands coordinate in a N^N bidentate mode to afford square planar compounds. Activation of the palladium(II) complexes with para-tolyl sulfonic acid (PTSA) afforded active catalysts in the methoxycarbonylation of a number of alkene. The resultant catalytic activities were controlled by the both the complex structure and alkene substrate. While aliphatic substrates favored the formation of linear esters (>70%), styrene substrate resulted in the formation of predominantly branched esters of up to 91%.
- Akiri, Saphan O.,Ojwach, Stephen O.
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- New ingenane and ingol diterpenoids from Euphorbia royleana
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Phytochemical investigation on the 95% EtOH extract of the Traditional Chinese Medicine (TCM) Euphorbia royleana (Ba-wang-bian in Chinese) led to the isolation of 11 diterpenoids (1–11) and two triterpenoids (12 and 13). Among them, compounds 1 and 2 were new ingenane and ingol diterpenoids, respectively. Their structures were elucidated by a combination of spectroscopic analyses (1 D and 2 D NMR, HRMS, ECD, UV, and IR data) and chemical methods. Compounds 12 and 13 exhibited moderate cytotoxicities in vitro against human lung cancer cell line A549 with IC50 values of 14.84 ± 0.56 and 27.11 ± 1.65 μM, respectively.
- Gan, Lu,Su, Tong,Wei, Xun,Wu, Shuqi,Yin, Sheng
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- Visible light-driven Giese reaction with alkyl tosylates catalysed by nucleophilic cobalt
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The scope of the Giese reaction is expanded using readily available alkyl tosylates as substrates and nucleophilic cobalt(i) catalysts under visible-light irradiation. The reaction proceeds preferentially with less bulky primary alkyl tosylates. This unique reactivity enables the regio-selective Giese reaction of polyol derivatives.
- Komeyama, Kimihiro,Michiyuki, Takuya,Teshima, Yoshikazu,Osaka, Itaru
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p. 3539 - 3546
(2021/02/03)
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- Dammarane triterpenoids from Carnauba, Copernicia prunifera (Miller) H. E. Moore (Arecaceae), wax
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Phytochemical investigation from carnauba (Copernicia prunifera) wax led to the identification of sixteen dammarane–type triterpenes, including thirteen new characterized as: (24R*)-methyldammara-20,25-dien-3α-ol and a mixture of alkyl (24R*)-methyldammar-25-en-20-ol-3β-carboxylates, together with three previously described triterpenes: carnaubadiol, (24R*)-methyldammara-20,25-dien-3β-ol and (24R*)-24-methyldammara-20,25-dien-3-one. Moreover, four fatty alcohols (eicosanol, docosanol, tetracosanol and hexacosanol) as well as four sterols (cholesterol, campesterol, stigmasterol, and sitosterol) were also obtained. These compounds were isolated using classical chromatographic methods and their structures were determined by spectroscopic and chemical methods.
- De Almeida, Buana C.,Araújo, Bruno Q.,Barros, Elcio D. S.,Freitas, Samya D. L.,Maciel, Dayany S. A.,Ferreira, Ari J. S.,Guadagnin, Rafael C.,Vieira, Gerardo M.,Lago, Jo?o H. G.,Chaves, Mariana H.
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p. 1371 - 1376
(2017/07/13)
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- Metathesis of renewable polyene feedstocks – Indirect evidences of the formation of catalytically active ruthenium allylidene species
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Cross-metathesis (CM) of conjugated polyenes, such as 1,6-diphenyl-1,3,5-hexatriene (1) and α-eleostearic acid methyl ester (2) with several olefins, including 1-hexene, dimethyl maleate and cis-stilbene as model compounds has been carried out using (1,3-bis-(2,4,6-trimethylphenyl)-2-imidazolidinylidene)-dichloro(o-isopropoxyphenylmethylene)ruthenium (Hoveyda-Grubbs 2nd generation, HG2) catalyst. The feasibility of these reactions is demonstrated by the observed high conversions and reasonable yields. Thus, regardless of the relatively low electron density, =CH–CH= conjugated units of molecules, including compound 2 as a sustainable, non-foodstuff source, can be utilized as building blocks for the synthesis of various value-added chemicals via olefin metathesis. DFT-studies and the product spectrum of the self-metathesis of 1,6-diphenyl-1,3,5-hexatriene suggest that a Ru η1-allylidene complex is the active species in the reaction.
- Kovács, Ervin,Sághy, Péter,Turczel, Gábor,Tóth, Imre,Lendvay, Gy?rgy,Domján, Attila,Anastas, Paul T.,Tuba, Róbert
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supporting information
p. 213 - 217
(2017/09/12)
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- Glycolipids produced by a Marine-derived Bacillus licheniformis
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The present invention provides a novel glycolipid compound which is produced by marine-derived Bacillus licheniformis and exhibits excellent activity to fungi and bacteria. The provided compound is represented by chemical formula 1 or chemical formula 2.COPYRIGHT KIPO 2017
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Paragraph 0040
(2017/06/09)
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- Pd-Catalyzed Regioselective Alkoxycarbonylation of 1-Alkenes Using a Lewis Acid [SnCl2 or Ti(OiPr)4] and a Phosphine
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The phosphine ligand mediated palladium catalyzed alkoxycarbonylation of alkenes was investigated with the objective of attaining good linear selectivity for the ester. The effect of various parameters such as solvents, additives, palladium precursors, CO pressures, and alkenes of various structural complexities were examined. The results revealed the importance of using a Lewis acid such as SnCl2 or Ti(OiPr)4 in combination with a monodentate ligand such CYTOP 292 or P(p-anisyl)3 to enhance the regioselectivity for the linear isomers in the range of 70-96%.
- Amézquita-Valencia, Manuel,Achonduh, George,Alper, Howard
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p. 6419 - 6424
(2015/06/30)
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- New secondary metabolites from croton sparsiorus morong
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Sparsioamide (1), a new sphingolipid, and sparsioside (2), a new diglyceride galactoside, have been isolated from the ethyl acetate soluble fraction of the 80% ethanolic extract of the whole plant of Croton sparsiorus Morong. Their structures were assigned by 1 H- and 13C-NMR spectra and DEPT, COSY, NOESY, HMQC, HMBC, and ESI-MS experiments. TUeBITAK.
- Mehmood, Rashad,Bibi, Amna,Malik, Abdul
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p. 111 - 118
(2013/05/08)
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- Lycopersicon esculentum Seeds: An industrial byproduct as an antimicrobial agent
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Lycopersicon esculentum (tomato) fruit is a widely studied matrix. However, only few works focus their attention on its seeds, which constitute a major byproduct of the tomato processing industry. In this study the antimicrobial potential of ten different tomato seed extracts from "Bull s heart" and "Cherry" varieties were analyzed against Gram-positive (Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus luteus, Enterococcus faecalis and Bacillus cereus) and Gram-negative (Proteus mirabilis, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhimurium) bacteria and fungi (Candida albicans, Aspergillus fumigatus and Trichophyton rubrum). Regarding antibacterial capacity, the different extracts were revealed to be active only against Gram-positive bacteria, E. faecalis being the most susceptible one (MIC: 2.5-10 mg/mL). Concerning antifungal activity, "Bull s heart" extracts were the most active. In a general way C. albicans was the most susceptible species (MIC: 5-10 mg/mL). The chemical composition of the extracts was also pursued, concerning organic acids, phenolics and fatty acids, in order to establish a possible relationship with the observed antimicrobial effect.
- Taveira, Marcos,Silva, Luis R.,Vale-Silva, Luis A.,Pinto, Eugenia,Valentao, Patricia,Ferreres, Federico,Guedes De Pinho, Paula,Andrade, Paula B.
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experimental part
p. 9529 - 9536
(2011/05/30)
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- DIRECT METHOD AND REAGENT KITS FOR FATTY ACID ESTER SYNTHESIS
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Provided are efficient, cost-effective and water tolerant methods (e.g., single-vial methods) for preparing fatty acid esters from organic matter, comprising: obtaining organic matter comprising at least one fat substituent, contacting the organic matter in a reaction mixture with a basic solution under conditions suitable to provide for hydrolytic release of monomeric fatty acids from the at least one fat substituent to provide a base-treated reaction mixture, and esterifying the monomeric fatty acids of the base-treated reaction mixture by acidification of the reaction mixture and treating in the presence of an organic alcohol to provide fatty acid esters. The methods optionally further comprise, prior to esterifying, neutralizing the base-treated reaction mixture to provide for neutralized fatty acids, separating the neutralized fatty acids from the neutralized reaction mixture, and dissolving the separated fatty acids in the esterification reaction mixture. Also provided are related methods and kits for fat analysis.
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Page/Page column 18; 21-22; 29
(2008/12/07)
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- Highly regioselective anti-markovnikov palladium-borate-catalyzed methoxycarbonylation reactions: Unprecedented results for aryl olefins
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(Chemical Equation Presented) A general, highly efficient and regioselective methoxycarbonylation, by means of a palladium-salicylicborate- catalyzed protocol, of terminal alkyl and aryl olefins is described. The substrates include aliphatic alkenes, allylbenzenes, and styrene derivatives. The yields are very good (60-92%) and the regioselectivity, in favor of the linear ester, is up to quantitative - unprecedented in the case of styrenes.
- Vieira, Tiago O.,Green, Mike J.,Alper, Howard
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p. 6143 - 6145
(2007/10/03)
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- Gracilarioside and gracilamides from the Red alga Gracilaria asiatica
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One gracilarioside and two gracilamides with unusual cyclopropane- containing alkyl chains were isolated from the red alga Gracilaria asiatica. Their structures were determined by spectroscopic methods and microscale chemical degradation. To our knowledge, no ceramides with a cyclopropane ring have been reported from marine organisms. These three compounds were mildly cytotoxic to the human A375-S2 melanoma cell line.
- Sun, Yi,Xu, Youjun,Liu, Kai,Hua, Huiming,Zhu, He,Pei, Yuehu
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p. 1488 - 1491
(2008/12/22)
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- Synthetic radical reactions using dibutylchlorogermane and dibutylethoxygermane as radical mediators
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In the presence of Et3B as radical initiator, dibutylchlorogermane (1a) and dibutylethoxygermane (1b) reacted with bromo- and iodoalkanes at room temperature to give the corresponding alkanes in high yields. Hydrogermane 1a was more reactive than 1b. However, 1b worked as a better radical mediator in intermolecular radical addition of haloalkanes to electron-deficient alkenes. Georg Thieme Verlag Stuttgart.
- Miura, Katsukiyo,Ootsuka, Kazunori,Hosomi, Akira
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p. 3151 - 3153
(2007/10/03)
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- Tandem isomerisation-carbonylation catalysis: Highly active palladium(II) catalysts for the selective methoxycarbonylation of internal alkenes to linear esters
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Fast, selective conversion of internal olefins to linear esters is catalysed by Pd(II) complexes of chelating bis (phosphaadamantyl)diphosphines and the catalysis is acutely sensitive to the ligand backbone and even to the diastereomer used; the results are compared with those for the PBut2 analogue.
- Pugh,Drent,Pringle
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p. 1476 - 1477
(2007/10/03)
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- Lutoside: An acyl-1-(Acyl-6'-mannobiosyl)-3-glycerol isolated from the Sponge-associated bacterium Micrococcus luteus
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Lutoside, an unusual acyl-1-(acyl-6'-mannobiosyl)-3-glycerol 1 was isolated from the sponge-associated bacterial strain Microccocus luteus. Structure elucidation was performed by spectroscopic analysis and chemical transformations.
- Bultel-Ponce, Valerie,Debitus, Cecile,Blond, Alain,Cerceau, Claude,Guyot, Michele
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p. 5805 - 5808
(2007/10/03)
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- Selective Mono- and Bis(alkoxycarbonylation)s of Olefins Catalyzed by Palladium in the Presence of Cu(I) or Cu(II) Chloride under Remarkably Mild Conditions. Application to the Synthesis of γ-Butyrolactone Derivatives
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Palladium-catalyzed mono- and bis(alkoxycarbonylation)s of the olefins were controlled by the use of copper(II) and copper(I) chloride, respectively, in alcohol under normal pressure of carbon monoxide and oxygen at room temperature without any other additives. 3-Buten-1-ols gave the corresponding γ-butyrolactones and 2-oxotetrahydrofuran-3-acetic acid esters, respectively, in high yields.
- Toda, Shiho,Miyamoto, Masanori,Kinoshita, Hideki,Inomata, Katsuhiko
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p. 3600 - 3606
(2007/10/02)
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- REACTION OF ALKOXYHYDROPEROXIDES WITH METAL SALTS. ALKYL HALIDE PREPARATION
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A synthesis is described of alkyl chlorides by reaction of methoxy hydroperoxides, prepared from 1-alkenes by ozonisation in methanol, with ferric chloride: RCH=CH2 --> RCH(OOH)OCH3 --> R. --> RCl.Yields of 1-chlorotetradecane were about 60percent; those of other halides from 38 to 57percent.
- Cardinale, G.,Grimmelikhuysen, J. C.,Laan, J. A. M.,Lier, F. P. van,Steen, D. van der,Ward, J. P.
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p. 5971 - 5978
(2007/10/02)
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- Bifunctional compounds from reaction of alkoxy hydroperoxides with metal salts
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Alkoxy hydroperoxides, obtained by ozonizing olefins in alcoholic solution, were treated with ferrous sulfate. C-C bond scission and radical formation was followed by dimerization of the radicals formed. Ozonides reacted similarly. Acyclic and cyclic olefins, including a cyclic enol ether, gave rise to a range of α,ω-disubstituted products in modest yields. By using ferric chloride, ω-chloro esters were obtained from the alkoxy hydroperoxides derived from olefinic esters.
- Cardinale,Laan,Van Der Steen,Ward
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p. 6051 - 6054
(2007/10/02)
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- SELECTIVE MIXED COUPLING OF CARBOXYLIC ACIDS (II). -PHOTOLYSIS OF UNSYMMETRICAL DIACYLPEROXIDES WITH ALKENYL-, HALO-, KETO-, CARBOXYL-GROUPS AND A CHIRAL α-CARBON. COMPARISON WITH THE MIXED KOLBE ELECTROLYSIS.
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- Alkenoyl and functionalized alkanoyl dodecanoyl peroxides are prepared in 70 to 97 percent yield and photolyzed at -78 deg C.Thereby 4- to 10-alkenoyl and 4-alkynoyl peroxides afford good yields (56 - 68 percent) of unsymmetrical coupling products.Similarly α- to δ-haloalkanoyl, cholanoyl or 3- and 4-carboxyalkanoyl peroxides can be coupled (40 - 70 percent).The α-chiral diacyl peroxide 1s undergoes the photochemical coupling reaction with 80 percent retention of its configuration.The photolysis of diacyl peroxides at -78 deg C proves to be a favorable supplement of the Kolbe-electrolysis in cases, where the electrolysis fails or produces low yields.
- Feldhues, Michael,Schaefer, Hans J.
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p. 4213 - 4236
(2007/10/02)
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- NEW CONCEPTS IN THE MECHANISM OF THE THERMAL DECOMPOSITION OF OZONIDES
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The mechanism for the thermal decomposition of ozonides which postulates the formation of the bipolar ion RC+H-OO- as an unstable intermediate is not in accordance with experiments on the decomposition of ozonides in methanol.A study
- Yur'ev, Yu. N.
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p. 1020 - 1024
(2007/10/02)
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- New Irritant Diterpene-esters from Roots of Stillingia Sylvatica L.(euphorbiaceae)
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From roots of Stillingia Sylvatica (Euphorbiaceae) eight more or less irritant Stillingia factors S1-S8 were isolated and identified as diterpene esters of the daphnane and tigliane types carrying saturated, polyunsaturated or hydroxilated fatty acids.
- Adolf, W.,Hecker, E.
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p. 2887 - 2890
(2007/10/02)
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- Method for converting unsaturated compound having functional group
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A method for the conversion of an unsaturated compound having a functional group, characterized by contacting [1] at least one compound selected from the group consisting of carboxylic acid esters, nitriles, ketones, amides, and ethers and having a carbon-to-carbon double bond and no unsaturation at the position conjugate to said double bond, or a mixture of said compound [1] and [2] at least one compound selected from the group consisting of ethylenically unsaturated compounds having a carbon-to-carbon double bond and neither unsaturation at the position conjugate to said double bond nor a functional group, with a catalyst system consisting essentially of a combination of (A) at least one member selected from the group consisting of tungsten compounds, molybdenum compounds, and rhenium compounds, with (B) at least one organoaluminum compound having at least one carbon-to-aluminum bond.
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