- Ring-opening metathesis polymerization (ROMP) of norbornenyl-functionalized fatty alcohols
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Novel biorenewable-based thermosets have been successfully synthesized by the ring-opening metathesis polymerization (ROMP) of norbornenyl-functionalized fatty alcohols derived from soybean oil (NMSA), Dilulin (NMDA), ML189 (NMMA) and castor oil (NMCA). The effects of the monomer structure on the polymerization process, and the thermal and mechanical properties of the resulting thermosets have been extensively investigated. The number of ROMP-reactive rings appended to the fatty acid chain and the viscosity play an important role in controlling the initiation and propagation processes of the polymerization and the final properties of the thermosets obtained. The thermosets have been characterized by Soxhlet extraction, DMA, TGA, and tensile tests. It has been found that polyNMDA and polyNMMA have best thermo-mechanical properties. Compared with polyNMSA, the polyNMDA and polyNMMA thermosets exhibit lower soluble fractions, and higher thermal stabilities and mechanical properties, because of more effective crosslinking; whereas, polyNMCA exhibits a higher soluble fraction, and lower thermal stability, resulting from incomplete polymerization of the more viscous NMCA monomer.
- Xia, Ying,Lu, Yongshang,Larock, Richard C.
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Read Online
- Enantiomeric synthesis of natural alkylglycerols and their antibacterial and antibiofilm activities
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Alkylglycerols (AKGs) are bioactive natural compounds that vary by alkyl chain length and degree of unsaturation, and their absolute configuration is 2S. Three AKGs (5l–5n) were synthesised in enantiomerically pure form, and were characterised for the first time together with 12 other known and naturally occurring AKGs (5a–5k, 5o). Their structures were established using 1H and 13C APT NMR with 2D-NMR, ESI-MS or HRESI-MS and optical rotation data, and they were tested for their antibacterial and antibiofilm activities. AKGs 5a–5m and 5o showed activity against five clinical isolates and P. aeruginosa ATCC 15442, with MIC values in the range of 15–125 μg/mL. In addition, at half of the MIC, most of the AKGs reduced S. aureus biofilm formation in the range of 23%–99% and P. aeruginosa ATCC 15442 biofilm formation in the range of 14%–64%. The antibiofilm activity of the AKGs assessed in this work had not previously been studied.
- Fernández Montoya, Deicy J.,Contreras Jordan, Luis A.,Moreno-Murillo, Bárbara,Silva-Gómez, Edelberto,Mayorga-Wandurraga, Humberto
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supporting information
p. 2544 - 2550
(2019/11/13)
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- Discovery of Anti-TNBC Agents Targeting PTP1B: Total Synthesis, Structure-Activity Relationship, in Vitro and in Vivo Investigations of Jamunones
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Twenty-three natural jamunone analogues along with a series of jamunone-based derivatives were synthesized and evaluated for their inhibitory effects against breast cancer (BC) MDA-MB-231 and MCF-7 cells. The preliminary structure-activity relationship revealed that the length of aliphatic side chain and free phenolic hydroxyl group at the scaffold played a vital role in anti-BC activities and the methyl group on chromanone affected the selectivity of molecules against MDA-MB-231 and MCF-7 cells. Among them, jamunone M (JM) was screened as the most effective anti-triple-negative breast cancer (anti-TNBC) candidate with a high selectivity against BC cells over normal human cells. Mechanistic investigations indicated that JM could induce mitochondria-mediated apoptosis and cause G0/G1 phase arrest in BC cells. Furthermore, JM significantly restrained tumor growth in MDA-MB-231 xenograft mice without apparent toxicity. Interestingly, JM could downregulate phosphatidylinositide 3-kinase (PI3K)/Akt pathway by suppressing protein-tyrosine phosphatase 1B (PTP1B) expression. These findings revealed the potential of JM as an appealing therapeutic drug candidate for TNBC.
- Hu, Caijuan,Li, Guoxun,Mu, Yu,Wu, Wenxi,Cao, Bixuan,Wang, Zixuan,Yu, Hainan,Guan, Peipei,Han, Li,Li, Liya,Huang, Xueshi
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supporting information
p. 6008 - 6020
(2021/05/06)
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- A Supramolecular Strategy for Selective Catalytic Hydrogenation Independent of Remote Chain Length
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Performing selective transformations on complex substrates remains a challenge in synthetic chemistry. These difficulties often arise due to cross-reactivity, particularly in the presence of similar functional groups at multiple sites. Therefore, there is a premium on the ability to perform selective activation of these functional groups. We report here a supramolecular strategy where encapsulation of a hydrogenation catalyst enables selective olefin hydrogenation, even in the presence of multiple sites of unsaturation. While the reaction requires at least one sterically nondemanding alkene substituent, the rate of hydrogenation is not sensitive to the distance between the alkene and the functional group, including a carboxylate, on the other substituent. This observation indicates that only the double bond has to be encapsulated to effect hydrogenation. Going further, we demonstrate that this supramolecular strategy can overcome the inherent allylic alcohol selectivity of the free catalyst, achieving supramolecular catalyst-directed regioselectivity as opposed to directing-group selectivity.
- Bender, Trandon A.,Bergman, Robert G.,Raymond, Kenneth N.,Toste, F. Dean
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supporting information
p. 11806 - 11810
(2019/08/22)
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- LINOLEIC ACID DERIVATIVES, PHARMACEUTICAL COMPOSITION OR FOOD COMPOSITION COMPRISING SAID LINOLEIC ACID DERIVATIVES, AND THEIR USES
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This invention relates to linoleic acid derivative of Formula (I) below comprising a hydrophobic part C17H31 linked to a polar head part "A": wherein said polar head part A is selected from A1 to A4 below: wherein R1 and R2 are independently selected from the group composed of H or a saturated or unsaturated, straight or branched alkyl group containing 1 to 8 carbon atoms, or R1 and R2 are linked together to form a divalent radical of formula -R1-R2-, wherein -R1-R2- is preferably -CH2-CH2- or-(CH2)3-; R3 is independently selected from the group composed of:
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Paragraph 0137; 0139; 0141-0142
(2019/12/16)
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- AMPHIPHILE PRODRUGS
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Amphiphilic prodrugs of general formula A-X are disclosed, wherein A is a biologically active agent or may be metabolised to a biologically active agent; and X is selected from the group consisting of R, or up to three R moieties attached to a linker, Y1, Y2 or Y3, wherein R is selected from a group consisting of alkyl, alkenyl, alkynyl, branched alkyl, branched alkenyl, branched alkynyl, substituted alkyl, substituted alkenyl and substituted alkynyl groups and their analogues; Y1 is a linker group which covalently attached to an R group at one site and is attached to A at a further independent site; Y2 is a linker group which is covalently attached to two R groups at two independent sites and is attached to A at a further independent site; and Y3 is a linker group which is covalently attached to three R groups at three independent sites and is attached to A at a further independent site. Self-assembly of the amphiphilic prodrugs into reverse lyotropic phases, particularly hexagonal, cubic and sponge, is disclosed. In preferred embodiments A is dopamine or a 5-fluorouracil prodrug.
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Page/Page column 0184
(2019/06/12)
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- Elongation of the Hydrophobic Chain as a Molecular Switch: Discovery of Capsaicin Derivatives and Endogenous Lipids as Potent Transient Receptor Potential Vanilloid Channel 2 Antagonists
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The transient receptor potential vanilloid type-2 (TRPV2) protein is a nonselective Ca2+ permeable channel member of the TRPV subfamily, still considered an orphan TRP channel due to the scarcity of available selective and potent pharmacological tools and endogenous modulators. Here we describe the discovery of novel synthetic long-chain capsaicin derivatives as potent TRPV2 antagonists in comparison to the totally inactive capsaicin, the role of their hydrophobic chain, and how the structure-activity relationships of such derivatives led, through a ligand-based approach, to the identification of endogenous long-chain fatty acid ethanolamides or primary amides acting as TRPV2 antagonists. Both synthetic and endogenous antagonists exhibited differential inhibition against known TRPV2 agonists characterized by distinct kinetic profiles. These findings represent the first example of both synthetic and naturally occurring TRPV2 modulators with efficacy in the submicromolar/low-micromolar range, which will be useful for clarifying the physiopathological roles of this receptor, its regulation, and its targeting in pathological conditions.
- Schiano Moriello, Aniello,López Chinarro, Silvia,Novo Fernández, Olalla,Eras, Jordi,Amodeo, Pietro,Canela-Garayoa, Ramon,Vitale, Rosa Maria,Di Marzo, Vincenzo,De Petrocellis, Luciano
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p. 8255 - 8281
(2018/09/25)
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- 3 - (1 - Piperazine - 4 - yl uncle ding yangtang acid radical) propionic acid amphiphilic derivatives and use thereof (by machine translation)
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The invention relates to an amphiphilic derivative of 3-(1-tert-butoxycarbonylpiperazin-4-yl)propionic acid, and a use thereof, and also relates to a liposome prepared from the amphiphilic derivative. The use is the use of the liposome as a drug carrier delivery system. The liposome prepared from the amphiphilic derivative can be compounded with gene drug siRNA to form a compound with small particle size and uniform particle size distribution. The amphiphilic derivative is electrically neutral in environment with the pH value of 7.4, increases the in vivo stability of the lipid compound and reduces cytotoxicity caused by too many positive charges. The liposome can specifically inhibit gene expression in human non-small cell lung cancer H1299-Pg13 cells in vitro, and can specifically transship fluorescence gene drugs into normal mouse liver cells in vivo.
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Paragraph 0052; 0070; 0072; 0073; 0074
(2018/07/30)
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- A Versatile Iridium(III) Metallacycle Catalyst for the Effective Hydrosilylation of Carbonyl and Carboxylic Acid Derivatives
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A versatile iridium(III) metallacycle catalysed rapidly and selectively the reduction of a large array of challenging esters and carboxylic acids as well as various ketones and aldehydes. The reactions proceeded in high yields at room temperature by hydrosilylation followed by desilylation. Although the reactions of various aldehydes and ketones resulted exclusively in alcohols, the hydrosilylation of esters led to alcohols or ethers, depending on the type of substrate. Regarding the carboxylic acids, again the nature of the reagent controlled the outcome of the hydrosilylation reaction, either alcohols or aldehydes being formed.
- Corre, Yann,Rysak, Vincent,Trivelli, Xavier,Agbossou-Niedercorn, Francine,Michon, Christophe
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supporting information
p. 4820 - 4826
(2017/09/07)
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- LIPID MEMBRANE STRUCTURE FOR siRNA INTRACELLULAR DELIVERY
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A lipid membrane structure encapsulating an siRNA inside thereof and containing a lipid compound of the formula (I) as a lipid component (R1 and R2 represent CH3—(CH2)n—CH═CH—CH2—CH═CH—(CH2)m—, n represents an integer of 3 to 5, m represents an integer of 6 to 10, p represents an integer of 2 to 7, and R3 and R4 represent a C1-4 alkyl group or a C2-4 alkenyl group.
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Paragraph 0086-0087
(2017/10/10)
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- 3 - ((2 - (Dimethylamino) ethyl) (methyl) amino) propionic acid amphiphilic derivatives and use thereof
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The invention relates to an amphiphilic derivative of 3-((2-dimethylamino)ethyl(methyl)amino)propionic acid, and a use thereof, and also relates to a liposome prepared from the above amphiphilic compound. The use is the use of the liposome as a drug carrier delivery system. The liposome prepared from the amphiphilic compound has many positive charges in acidic environment, and can be well compounded with gene drug siRNA to form a compound with small particle size and uniform particle size distribution. The amphiphilic compound is electrically neutral in environment with the pH value of 7.4, increases the in vivo stability of the lipid compound and reduces cytotoxicity caused by too many positive charges. The liposome can specifically inhibit gene expression in human non-small cell lung cancer H1299-Pg13 cells in vitro, and can specifically transship fluorescence gene drugs into normal mouse liver cells in vivo.
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Paragraph 0053; 0071-0077
(2018/01/05)
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- Catalytic Ester Metathesis Reaction and Its Application to Transfer Hydrogenation of Esters
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We report a Ru-complex-catalyzed ester metathesis reaction where an unsymmetrical ester such as ethyl hexanoate can be transformed to a mixture of starting material, hexyl ethanoate, ethyl acetate, and hexyl hexanoate in equal proportions, as expected from a classical metathesis reaction with 0.2 mol % catalyst. A 20× excess of low boiling alcohol, such as ethanol, allows for the transfer of an acyl moiety to the sacrificial low boiling ethyl acetate product, while significantly increasing the functional group tolerance and substrate scope; yields of alcohols can reach 90%, which represents an attractive alternative to current high H2 pressure hydrogenation protocols for Ru-based ester reduction chemistry. Both reactions have not been reported previously in the field of Ru-catalyzed transformations of the ester functionality.
- Dubey, Abhishek,Khaskin, Eugene
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p. 3998 - 4002
(2016/07/06)
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- Tuning the Thermo-Sensitivity of Micellar Systems through a Blending Approach
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This paper reports an original and easy route toward thermosensitive micelles based on a lipidic core and with adjustable cloud point temperatures (TCP) through a simple blending approach between two copolymers of different TCP. The cationic ring-opening polymerization (CROP) of various 2-alkyl-2-oxazoline monomers was first investigated from both mesylated and tosylated lipoinitiators and different lipid-b-poly(2-methyl-2-oxazoline), lipid-b-poly(2-ethyl-2-oxazoline), lipid-b-poly(2-isopropyl-2-oxazoline) and lipid-b-poly((2-ethyl-2-oxazoline)-co-(2-isopropyl-2-oxazoline)) copolymers were synthesized. Blending of lipid-b-p(EtOx) and lipid-b-p(iPrOx) copolymers in various proportions were then prepared and their TCP investigated through UV-visible spectroscopy. Very interesting results were obtained as the blends exhibit a single TCP ranging from 35 to 45 °C. Furthermore, the blends TCP correspond to those of the statistical lipid-b-p((EtOx)-co-(iPrOx)) for the same p(EtOx)/p(iPrOx) content up to 52 wt % of p(EtOx). The blending approach is then an attractive strategy to control the TCP of micellar systems through a simple and easy formulation approach rather than fastidious syntheses.
- El Asmar, Arlette,Gimello, Olinda,Morandi, Ga?lle,Le Cerf, Didier,Lapinte, Vincent,Burel, Fabrice
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p. 4307 - 4315
(2016/07/06)
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- Lipid formulations
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The invention features a cationic lipid of formula I, an improved lipid formulation comprising a cationic lipid of formula I and corresponding methods of use. Also disclosed are targeting lipids, and specific lipid formulations comprising such targeting lipids.
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Page/Page column 115; 117
(2016/08/17)
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- The lipid membrane structure (by machine translation)
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PROBLEM TO BE SOLVED: siRNA of Hepatocytic nucleic acid or the like can be efficiently deliver glycolipid film structure of the carrier. SOLUTION: eq. (I) (R the eq. (A) or eq. (B) a group represented by (n is 2 from 4 integer, m is an integer of from 2 5)) as a compound represented by structure including glycolipid glycolipid film. Selected drawing: no (by machine translation)
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Paragraph 0041; 0042
(2017/04/11)
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- Design and synthesis of protein kinase C epsilon selective diacylglycerol lactones (DAG-lactones)
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DAG-lactones afford a synthetically accessible, high affinity platform for probing structure activity relationships at the C1 regulatory domain of protein kinase C (PKC). Given the central role of PKC isoforms in cellular signaling, along with their differential biological activities, a critical objective is the design of isoform selective ligands. Here, we report the synthesis of a series of DAG-lactones varying in their side chains, with a particular focus on linoleic acid derivatives. We evaluated their selectivity for PKC epsilon versus PKC alpha both under standard lipid conditions (100% phosphatidylserine, PS) as well as in the presence of a nuclear membrane mimetic lipid mixture (NML). We find that selectivity for PKC epsilon versus PKC alpha tended to be enhanced in the presence of the nuclear membrane mimetic lipid mixture and, for our lead compound, report a selectivity of 32-fold.
- Ann, Jihyae,Yoon, Suyoung,Baek, Jisoo,Kim, Da Hye,Lewin, Nancy E.,Hill, Colin S.,Blumberg, Peter M.,Lee, Jeewoo
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p. 332 - 341
(2015/05/04)
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- LIPIDOSOME PREPARATION, PREPARATION METHOD AND APPLICATION THEREOF
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The present invention discloses a liposome formulation, its preparation method, and its application in the treatment of diseases caused by abnormal gene expression. The liposome formulation comprises complementary cationic lipid pairs, phospholipids, and long-circulating lipids. The method of preparing the liposome formulation comprises: mixing the complementary cationic lipid pairs with the phospholipid and the long-circulating lipid to generate pre-formed vesicles; and then mixing the pre-formed vesicles with the nucleic acid solution to generate the liposome-nucleic acid formulation. This liposome formulation provided by the present invention is easily prepared; and in the treatment of diseases caused by abnormal gene expression, the liposome formulation can be used to deliver in vivo therapeutic agents, including nucleic acids.
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Paragraph 0035-0036
(2015/12/20)
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- Improved glycolipid preparation
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The invention features a cationic lipid of formula (I), an improved lipid formulation comprising a cationic lipid of formula I and corresponding methods of use. Also disclosed are targeting lipids, and specific lipid formulations comprising such targeting lipids.
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Paragraph 0447
(2016/12/12)
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- Cationic substrates of soybean lipoxygenase-1
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Soybean lipoxygenase-1 (SBLO-1) catalyzes the oxygenation of 1,4-dienes to produce conjugated diene hydroperoxides. The best substrates are anions of fatty acids; for example, linoleate is converted to 13(S)-hydroperoxy-9(Z),11(E)- octadecadienoate. The manner in which SBLO-1 binds substrates is uncertain. In the present work, it was found that SBLO-1 will oxygenate linoleyltrimethylammonium ion (LTMA) to give primarily13(S)-hydroperoxy-9(Z), 11(E)-octadecadienyltrimethylammonium ion. The rate of this process is about the same at pH 7 and pH 9 and is about 30% of the rate observed with linoleate at pH 9. At pH 7, SBLO-1 oxygenates linoleyldimethylamine (LDMA) to give primarily 13(S)-hydroperoxy-9(Z),11(E)-octadecadienyldimethylamine. The oxygenation of LDMA occurs at about the same rate as LTMA at pH 7, but more slowly at pH 9. The results demonstrate that SBLO-1 will readily oxygenate substrates in which the carboxylate of linoleate is replaced with a cationic group, and the products of these reactions have the same stereo- and regiochemistry as the products obtained from fatty acid substrates.
- Chohany, Lucas E.,Bishop, Kathleen A.,Camic, Hannah,Sup, Stephen J.,Findeis, Peter M.,Clapp, Charles H.
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scheme or table
p. 94 - 100
(2011/06/11)
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- Synthesis and pharmacological evaluation of sulfamide-based analogues of anandamide
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Arachidonyl and linoleyl sulfamide derivatives have been synthesized and their potential cannabimimetic properties evaluated in in vitro functional and binding assays. Replacement of the ethanolamide moiety of anandamide by -CH2NHSO2NH-R considerably reduces the CB1 receptor activity and only some of the compounds showed modest cannabinoid properties in binding assays. The new compounds were also tested as inhibitors of the FAAH enzyme but were inactive.
- Cano, Carolina,Paez, Juan Antonio,Goya, Pilar,Serrano, Antonia,Pavon, Javier,Rodriguez de Fonseca, Fernando,Suardiaz, Margarita,Martin, Maria Isabel
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scheme or table
p. 4889 - 4895
(2010/03/01)
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- New N-arachidonoylserotonin analogues with potential "dual" mechanism of action against pain
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N-Arachidonoylserotonin (AA-5-HT, 1a) is an inhibitor of fatty acid amide hydrolase (FAAH) that acts also as an antagonist of transient receptor potential vanilloid-type 1 (TRPV1) channels and is analgesic in rodents. We modified the chemical structure of 1a with the aim of developing "hybrid" FAAH/TRPV1 blockers more potent than the parent compound or obtaining analogues with single activity at either of the two targets to study the mechanism of the analgesic action of 1a. Thirty-eight AA-5-HT analogues, containing a serotonin "head" bound to a variety of lipophilic moieties via amide, urea, or carbamate functionalities, were synthesized. Unlike 1a, most of the new compounds possessed activity at only one of the two considered targets. The amides 1b and 1c of α- and γ-linolenic acid, however, showed "hybrid" activity similar to 1a. The carbamate 3f (OMDM106), although unable to antagonize TRPV1 receptors, was the most potent FAAH inhibitor in this study (IC50 = 0.5 μM). Compounds 3f and 1m (OMDM129), which exhibited activity at only FAAH or TRPV1, respectively, were 10-fold less potent than 1a at preventing formalin-induced hyperalgesia in mice.
- Ortar, Giorgio,Cascio, Maria Grazia,De Petrocellis, Luciano,Morera, Enrico,Rossi, Francesca,Schiano-Moriello, Aniello,Nalli, Marianna,De Novellis, Vito,Woodward, David F.,Maione, Sabatino,Di Marzo, Vincenzo
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p. 6554 - 6569
(2008/09/17)
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- Synthesis of a tetronic acid library focused on inhibitors of tyrosine and dual-specificity protein phosphatases and its evaluation regarding VHR and Cdc25B inhibition
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Selective inhibitors of protein tyrosine phosphatases (PTPs) and dual-specificity phosphatases (DSPs) are expected to be useful tools for clarifying the biological functions of the PTPs themselves and also to be candidates for novel therapeutics. We planned a library approach for the identification of PTP/DSP inhibitors in which 3-acyltetronic acid is used as a "core" phosphate mimic. A series of novel tetronic acid derivatives were synthesized and evaluated as inhibitors of the dual-specificity protein phosphatases VHR and cdc25B. Several compounds are found to be potent inhibitors of cdc25B, which is a key enzyme for cell-cycle progression. The promising results described herein strongly indicated that this tetronic acid library is potent as a library focused on the PTP/DSP-selective inhibitor.
- Sodeoka,Sampe,Kojima,Baba,Usui,Ueda,Osada
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p. 3216 - 3222
(2007/10/03)
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- Synthesis of cis-12,13-epoxy-cis-9-octadecenol and 12(13)-hydroxy-cis-9-octadecenol from vernonia oil using lithium aluminum hydride
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Reduction of vernonia oil methyl esters (VOME) into epoxy fatty alcohol and diols was achieved with lithium aluminum hydride (LAH), under reflux and room temperature conditions, by using hexane and tetrahydrofuran (THF) as solvents. The reactions of VOME with LAH in hexane produced cis-12,13-epoxy-cis-9-octadecenol as a major product with an isolated yield of 73.62%, whereas the reactions with LAH in THF gave isomers of 12(13)-hydroxy-cis-9-octadecenol as the major products with an isolated yield of 95.1%. LAH was similarly reacted with vernonia oil (VO) to give the same products in lower yields, 1H nuclear magnetic resonance (NMR), 13C NMR, gas chromatography-mass spectrometry, and infrared were used to characterize these products. This study demonstrates the ability to control the reactivity of the epoxy functionality in VO or VOME with the choice of polar or nonpolar solvents, and extends the range of oleochemicals that can be derived from vernonia oil.
- Elhilo, Eisa B.,Anderson, Melissa A.,Ayorinde, Folahan O.
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p. 873 - 878
(2007/10/03)
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- Synthesis of phosphatidylcholine having a very long chain polyunsaturated fatty acid
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A phosphatidylcholine 9 bearing icosadienoyl and docosahexaenoyl groups at the 1-and 2-positions respectively was synthesized. The synthetic route involves carbon chain elongation of linoleic acid via malonic ester synthesis, preparation of lyso-phosphatidylcholine via lipase-catalyzed mono-acylation of 2-O-methoxyethoxymethylglycerol and phosphodiester synthesis, and finally DCC-mediated esterification.
- Haider, Syed Shabbir,Tanaka, Masatoshi,Alam, Md Khorshed,Nakajima, Shuhei,Baba, Naomichi,Shimizu, Sakayu
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p. 175 - 176
(2007/10/03)
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- Selective one-pot conversion of carboxylic acids into alcohols
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Carboxylic acids are converted into alcohols by chemoselective reduction of their corresponding fluorides with sodium borohydride and dropwise addition of methanol. The method is general and mild and displays a high level of functional group compatibility. N-Protected amino and peptide alcohols, bearing varieties of protecting groups, are prepared in the same way from their corresponding amino acids and peptides without racemization.
- Kokotos, George,Noula, Caterina
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p. 6994 - 6996
(2007/10/03)
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- Mammalian Exocrine Secretions: IX. Constituents of Preorbital Secretion of Oribi, Ourebia ourebi
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Using gas chromatography-mass spectrometry in conjunction with ancillary techniques such as chemical ionization with different reactant gases, determination of the position of double bonds by means of dimethyl disulfide derivatization, and finally gas chromatographic and mass spectrometric comparison with authentic synthetic material, 75 constituents were identified in the preorbital secretion of the male oribi, Ourebia ourebi. The secretion contains compounds with long-chain, unbranched structures similar to those found in many other preorbital secretions but with a finite volatility range, in contrast to the seemingly endlessly increasing chain lengths typical of other preorbital secretions.
- Mo, W.-P.,Burger, B. V.,LeRoux, M.,Spies, H. S. C.
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p. 1191 - 1216
(2007/10/03)
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- Synthesis of Very Long Fatty Acid Methyl Esters
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Phosphoranes, produced by treating alkyltriphenylphosphonium bromides with lithium hexamethyldisilazide, reacted with ω-oxo esters to give modest yields of the corresponding methyl cis-alkenoates.By an alternative method, treatment of ω-iodo esters with the complexes formed from reactions of alkylcopper(I) and Grignard reagents gave methyl alkanoates, cis-alkenoates, and methylene-interrupted cis,cis-alka-dienoates and cis,cis,cis-trienoates.The stereochemical integrity of the esters was determined by 13C NMR spectroscopy.
- Kling, Marcel R.,Easton, Christopher J.,Poulos, Alf
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p. 1183 - 1190
(2007/10/02)
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- Furanone derivatives
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This invention provides certain furanone derivatives, their pharmaceutical formulations, and their use in a method for treating inflammation, asthma, or allergies.
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- An Electron Spin Resonance Study of Fatty Acids and Esters. Part 1. Hydrogen Abstraction from Olefinic and Acetylenic Long-chain Esters
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The radicals generated from unsaturated fatty acid esters by hydrogen abstraction with photochemically formed t-butoxyl radicals have been investigated by e.s.r. spectroscopy.The substituted allyl and pentadienyl radicals generated from monoenoic and dienoic esters were conformationally stable under the conditions of the experiments.The main species observed on hydrogen-abstraction from monoynoic esters were substituted propynyl radicals, and the same radical type was generated from diynoic esters with more than one methylene unit separating the triple bonds.Substituted penta-1,4-diynyl and penta-1,3-diynyl radicals were identified on hydrogen-abstraction from methylene-interrupted and conjugated diynoic esters.Hydrogen abstraction from triacylglycerols containing one or more double bonds was also examined.Most of the unsaturated esters also gave rise to secondary radicals produced by hydrogen-abstraction from the chain methylene groups.From the measured concentrations of the secondary and delocalised radicals the following approximate relative rates of hydrogen-abstraction by t-butoxyl radicals from the different sites were obtained: secondary: propynylic: allylic: bisallylic = 1:18:36:116 at 293 K.
- Bascetta, Emanuele,Gunstone, Frank D.,Walton, John C.
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p. 603 - 614
(2007/10/02)
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- Polyene Pheromone Components from an Arctiid Moth (Utetheisa ornatrix): Characterization and Synthesis
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In our earlier study of the female sex attractant from an arctiid moth (Utetheisa ornatrix), the occurence of an uncharacterized C-21 tetraene was noted along with (Z,Z,Z)-3,6,9-heneicosatriene, the major pheromone constituent.The sex attractant glands of females from other populations of this moth have now yielded this C-21 tetraene as a major component, accompanied by a new C-21 diene.Spectral and chemical studies of these two EAG-active compounds led to their characterization as (Z,Z,Z)-1,3,6,9-heneicosatetraene and (Z,Z)-6,9-heneicosadiene.These structures and configurations were confirmed by synthesis.
- Jain, Subhash C.,Dussourd, David E.,Conner, William E.,Eisner, Thomas,Guerrero, Angel,Meinwald, Jerrold
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p. 2266 - 2270
(2007/10/02)
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- SOLUBILIZATION AND PROPERTIES OF THE ENZYME-CLEAVING 13-L-HYDROPEROXYLINOLENIC ACID IN TEA LEAVES
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The membrane bound hydroperoxide lyase (E2'') which catalyses the cleavage of 13-L-hydroperoxides (18:3-OOH and 18:2-OOH) of linolenic and linoleic acids to C6-volatile aldehydes (hexenals and n-hexanal) was found to be localized in the chloroplast lamellae of tea leaves.It was selectively solubilized from the lamellae with 0.5percent (w/v) Tween 20.The enzymatic cleavage of the hydroperoxides occurred even under anaerobic conditions.The optimal pH of E2'' was 7-8.The common structural features shown by substrates of E2'' were the presence of a L-hydroperoxy group at ω-6 with a conjugated trans, cis-diene at ω-7 and ω-9 in a C18-fatty acid.E2'' had an apparent Km of 2.5 and 1.9 mM for 18:3-OOH and 18:2-OOH, respectively.No significant differences were found between chloroplast E2'' and solubilized E2''. - Key Word Index - Thea sinensis; Theaceae; tea; hydroperoxide lyase; hexenals; 13-L-hydroperoxylinolenic acid.
- Hatanaka, A.,Kajiwara, T.,Sekiya, J.,Inouye, S.
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- Fluorescein esters and ethers and the preparation thereof
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Fluorescein esters and ethers including the dioleyl derivative of fluorescein are disclosed. These compounds have the useful property of being fluorescent under the influence of the proper frequency of electromagnetic irradiation. Further, dioleyl fluorescein is readily incorporated into low-density lipoproteins which can then become part of the cell matter; the compounds retain their fluorescent properties during this procedure. The fluorescence allows cells to be identified and separated. The fluorescein esters and ethers are prepared from fluorescein and the novel reagent O-alkenyl-N,N'-dialkylisourea.
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- A NEW METHOD FOR CLEAVAGE OF ALIPHATIC METHYL ETHERS
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A new efficient procedure for the cleavage of aliphatic methyl ethers under the mild conditions by the use of the reagents system, boron tribromide - sodium iodide - 15-crown-5 is described.
- Niwa, Haruki,Hida, Tsuneaki,Yamada, Kiyoyuki
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p. 4239 - 4240
(2007/10/02)
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