- Humidity sensor based on a cross-linked porous polymer with unexpectedly good properties
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A humidity sensitive polymer was synthesized based on the derivative of triphenylphosphine by Friedel-Crafts alkylation. The polymer was formed of a hydrophobic skeleton with hydrophilic ions modified on phosphorous atoms evenly. The resultant polymer shows nanoporous characteristics. A humidity sensor based on the amphiphilic porous polymer shows unexpectedly good sensing properties, including high sensitivity, small humidity hysteresis, rapid response and recovery, and good stability. The good stability of the sensor is attributed to the cross-linked skeleton structure of the polymer, even though the content of ions in the polymer is high. These results demonstrate that porous polymers modified with certain hydrophilic groups are promising materials for high performance humidity sensors. This journal is the Partner Organisations 2014.
- Fei, Teng,Jiang, Kai,Liu, Sen,Zhang, Tong
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Read Online
- CYCLOALKYL-CONTAINING CARBOXYLIC ACIDS AND USES THEREOF
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The present application discloses a compound of formula (I) or a salt thereof: (I) and compositions comprising such compound or salt thereof. The use of such compound, salt thereof or composition comprising same for treating anemia or leukopenia, fibrosis, cancer, hypertension and/or a metabolic condition in a subject is also disclosed.
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Page/Page column 67
(2021/06/26)
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- Visible Light Induced Cyclization to Spirobi[indene] Skeletons from Functionalized Alkylidienecyclopropanes
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In this paper, we revealed a metal-free and visible light photoinduced method for the rapid construction of spirobi[indene] skeletons, providing a simple and efficient way for easy access to spirobi[indene] scaffolds under mild conditions along with a broad substrate scope and good functional group tolerance.
- Li, Quanzhe,Liu, Jiaxin,Shi, Min,Wei, Yin
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supporting information
(2020/03/26)
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- Tergal Gland Secretion of the Rove Beetle Aleochara pseudochrysorrhoa (Staphylinidae: Aleocharinae): Chemical Composition and Biological Roles
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Aleochara pseudochrysorrhoa has a glandular complex known as the tergal gland. Generally, the tergal gland secretion (TGS) has been described to have defensive function, but some reports point to a possible secondary function of this complex. For example, the TGS of the related species A. curtula has been demonstrated to possess an important role in intraspecies communication. In this work, we describe the chemical composition of the TGS of A. pseudochrysorrhoa males and females. Eleven compounds were identified based on GC/MS and GC-FT-IR analyses, retention indexes and derivatization products. Furthermore, a brief study regarding the biological function of the TGS in mating behavior is provided, in which the stimulation of male grasping response reaction by female TGS proved to be dependent on concentration.
- da Silva, Maycon R.,Vidal, Diogo M.,Figueiredo, Leonardo,Bandeira, Pamela T.,Bergmann, Jan,Zarbin, Paulo H. G.
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- Exploring London Dispersion and Solvent Interactions at Alkyl–Alkyl Interfaces Using Azobenzene Switches
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Interactions on the molecular level control structure as well as function. Especially interfaces between innocent alkyl groups are hardly studied although they are of great importance in larger systems. Herein, London dispersion in conjunction with solvent interactions between linear alkyl chains was examined with an azobenzene-based experimental setup. Alkyl chains in all meta positions of the azobenzene core were systematically elongated, and the change in rate for the thermally induced Z→E isomerization in n-decane was determined. The stability of the Z-isomer increased with longer chains and reached a maximum for n-butyl groups. Further elongation led to faster isomerization. The origin of the intramolecular interactions was elaborated by various techniques, including 1H NOESY NMR spectroscopy. The results indicate that there are additional long-range interactions between n-alkyl chains with the opposite phenyl core in the Z-state. These interactions are most likely dominated by attractive London dispersion. This work provides rare insight into the stabilizing contributions of highly flexible groups in an intra- as well as an intermolecular setting.
- Strauss, Marcel A.,Wegner, Hermann A.
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supporting information
p. 18552 - 18556
(2019/11/19)
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- Organoselenium-catalyzed synthesis of oxygen- and nitrogen-containing heterocycles
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A new and efficient approach for the synthesis of oxygen and nitrogen heterocycles by organoselenium catalysis has been developed. The exo-cyclization proceeded smoothly under mild conditions with good functional group tolerance and excellent regioselectivity. Mechanistic studies revealed that 1-fluoropyridinium triflate is key for oxidative cyclization.
- Guo, Ruizhi,Huang, Jiachen,Huang, Haiyan,Zhao, Xiaodan
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supporting information
p. 504 - 507
(2016/02/18)
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- TREATMENT OF H. PYLORI INFECTIONS USING MTAN INHIBITORS
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Methods of treating infections due to Helicobacter pylori (H. pylori), in particular in subjects having a peptic ulcer, are disclosed where the methods comprise administering inhibitors of H. pylori MTAN (5'-methylthioadenosine nucleosidase) to the subject.
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Paragraph 0082
(2015/09/22)
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- New Antibiotic Candidates against Helicobacter pylori
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Helicobacter pylori is a Gram-negative bacterium that colonizes the gut of over 50% of the worlds population. It is responsible for most peptic ulcers and is an important risk factor for gastric cancer. Antibiotic treatment for H. pylori infections is challenging as drug resistance has developed to antibiotics with traditional mechanisms of action. H. pylori uses an unusual pathway for menaquinone biosynthesis with 5′-methylthioadenosine/S-adenosylhomocysteine nucleosidase (MTAN) catalyzing an essential step. We validated MTAN as a target with a transition-state analogue of the enzyme [Wang, S.; Haapalainen, A. M.; Yan, F.; et al. Biochemistry 2012, 51, 6892-6894]. MTAN inhibitors will only be useful drug candidates if they can both include tight binding to the MTAN target and have the ability to penetrate the complex cell membrane found in Gram-negative H. pylori. Here we explore structural scaffolds for MTAN inhibition and for growth inhibition of cultured H. pylori. Sixteen analogues reported here are transition-state analogues of H. pylori MTAN with dissociation constants of 50 pM or below. Ten of these prevent growth of the H. pylori with IC90 values below 0.01 μg/mL. These remarkable compounds meet the criteria for potent inhibition and cell penetration. As a consequence, 10 new H. pylori antibiotic candidates are identified, all of which prevent H. pylori growth at concentrations 16-2000-fold lower than the five antibiotics, amoxicillin, metronidazole, levofloxacin, tetracyclin, and clarithromycin, commonly used to treat H. pylori infections. X-ray crystal structures of MTAN cocrystallized with several inhibitors show them to bind in the active site making interactions consistent with transition-state analogues.
- Wang, Shanzhi,Cameron, Scott A.,Clinch, Keith,Evans, Gary B.,Wu, Zhimeng,Schramm, Vern L.,Tyler, Peter C.
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supporting information
p. 14275 - 14280
(2015/11/28)
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- Toxicity assessment of phosphonium based ionic liquids towards female guppy fish
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In this study, two phosphonium based ionic liquids (butyl triphenyl phosphonium chloride and hexyl triphenyl phosphonium bromide) have been synthesized using quarternization process. The toxicities of these ionic liquids are unknown and may be harmful to humans and the environment. Therefore, the toxicity assessment of these ionic liquids was carried out according to the Organization for Economic Cooperation and Development (OECD) guideline 203 using female guppy fish (Poecilia reticulata). The median lethal concentrations (LC50) have been estimated for butyl triphenyl phosphonium chloride and for hexyl triphenyl phosphonium bromide to be 73.35 mg/L and 61.36 mg/L respectively. Both LC50 obtained can be identified as slightly toxic ionic liquids based on Acute Toxicity Rating Scale by by the United States Fish and Wildlife Service (USFWS). The findings from this study can be used for better design of phosphonium-based ionic liquids with consideration of their aquatic toxicities.
- El-Harbawi, Mohanad,Yusri, Yasmin Syazwani Bt.,Hossain, M. Ismail
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p. 2997 - 3000
(2014/06/09)
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- Catalytic enantioselective 1,2-diboration of 1,3-dienes: Versatile reagents for stereoselective allylation
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More with boron: The development of catalytic enantioselective 1,2-diboration of 1,3-dienes enables a new strategy for enantioselective carbonyl allylation reactions (see scheme). These reactions occur with outstanding levels of stereoselection and can be applied to both monosubstituted and 1,1-disubstituted dienes. The carbonyl allylation reactions provide enantiomerically enriched functionalized homoallylic alcohol products. Copyright
- Kliman, Laura T.,Mlynarski, Scott N.,Ferris, Grace E.,Morken, James P.
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supporting information; experimental part
p. 521 - 524
(2012/03/11)
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- A total synthesis of natural Rhizobialide
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Natural butanolide Rhizobialide was synthesized for the first time in enantiopure form with the stereogenic center derived from glutamic acid.
- Guan, Jing,Zou, Yang,Gao, Po,Wu, Yikang,Yue, Zhengyu
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experimental part
p. 1613 - 1617
(2011/07/08)
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- Effects of lipid chain lengths in α-galactosylceramides on cytokine release by natural killer T cells
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Glycolipid presentation by CD1 proteins has emerged as an important aspect of antigen recognition, and presentation of α-glycosylceramides by CD1d to natural killer T cells has become a central focus in understanding how glycolipid presentation can influence immune responses. An α-galactosylceramide containing relatively long lipid chains has been the subject of intense study because, when presented by CD1d to natural killer T cells, it stimulates the release of both proinflammatory and immunomodulatory cytokines. Using an efficient synthesis of α-galactosylceramides, we have prepared a series of glycolipids in which the lipid chain lengths have been incrementally varied. The responses of natural killer T cells to these glycolipids have been determined, and we have found that truncation of the phytosphingosine lipid chain increases the relative amounts of immunomodulatory cytokines released. In similar fashion, the length of the acyl chain in α-galactosylceramides influences cytokine release profiles. Copyright
- Goff, Randal D.,Gao, Ying,Mattner, Jochen,Zhou, Dapeng,Yin, Ning,Cantu III, Carlos,Teyton, Luc,Bendelac, Albert,Savage, Paul B.
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p. 13602 - 13603
(2007/10/03)
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- Synthesis of phosphonium salts under microwave activation - Leaving group and phosphine substituents effects
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The specific nonpurely thermal effects of microwaves were evidenced according to neutral or charged leaving groups during nucleophilic substitution of benzylic electrophiles with triphenylphosphine and tributylphosphine. Microwave (MW) irradiation considerably enhanced the reactions with charged alkylating agents, especially under solvent-free conditions. Results are interpreted considering the magnitude of MW effects according to the position of the transition state along the reaction coordinates.
- Cvengros, Jan,Toma, Stefan,Marque, Sylvain,Loupy, Andre
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p. 1365 - 1371
(2007/10/03)
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- Synthesis of isotopically labeled arachidonic acids to probe the reaction mechanism of prostaglandin H synthase
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Prostaglandin H synthase (PGHS) catalyzes the conversion of arachidonic acid to prostaglandin G2 in the cyclooxygenase reaction. The first step of the mechanism has been proposed to involve abstraction of the pro-S hydrogen atom from C13 to generate a pentadienyl radical spanning C11-C15. We report here the synthesis of six site-specifically deuterated arachidonic acids to investigate the structure of the radical intermediate. The preparation of these compounds was achieved using a divergent scheme that involved one advanced intermediate for all targets. The synthetic design introduced the label late in the routes and allowed the utilization of common synthetic intermediates in the preparation of various targets. Both 13(R)- and 13(S)-deuterium-labeled arachidonic acids were synthesized in high enantiomeric purity as deduced from soybean lipoxygenase assays and mass spectrometric analysis of the resulting enzymatic products. Each synthetic compound was reacted under anaerobic conditions with the wide singlet tyrosyl radical of PGHS-2 to generate a radical intermediate that was analyzed by EPR. Deuterium substitution at positions 11, 13(S), and 15 resulted in the loss of one hyperfine interaction, indicating that the protons at these positions interact with the unpaired electron. Simulation of the spectra was achieved with one set of parameters that are consistent with the assignment of a pentadienyl radical. Use of 16-[2H2]-arachidonic acid indicated that only one of the protons at C16 gives rise to a strong hyperfine interaction. The findings are discussed in the context of two proposed mechanisms for the cyclooxygenase reaction.
- Peng, Sheng,Okeley, Nicole M.,Tsai, Ah-Lim,Wu, Gang,Kulmacz, Richard J.,Van der Donk, Wilfred A.
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p. 10785 - 10796
(2007/10/03)
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- Synthesis and biological activity of new diarylalkenes
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Condensation of 5-nitro-, 3-chloro-, and 5-chlorosalicylic acid with formaldehyde afforded dimeric disalicylmethanes which were O-methylated with dimethyl sulfate and oxidized with chromium(VI) oxide to give the diarylketones 10, 11, 12. Wittig reaction with ylides obtained by deprotonation of alkyltriphenylphosphonium salts with sodium bis (trimethylsilyl)amide yielded a series of diarylalkenes. Some of the obtained compounds showed high antimicrobial activity in vitro against Bacillus subtilis and Mycobacterium smegmatis.
- Golebiewski, W. Marek,Cieniecka-Ros?onkiewicz,Szybinska
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- Synthesis of α-tocopherol analogues
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A range of α-tocopherol analogues of varying side-chain length and structure has been prepared by the Wittig reaction of alkyltriphenylphosphonium bromides with either 6-benzyloxy-2,5,7,8-tetramethylchroman-2-carbaldehyde (8) or 6-acetoxy-2,5,7,8,-tetramethylchroman-2-carbaldehyde (14). These analogues include 2-hexyl-2,5,7,8-tetramethylchroman-6-ol (11), 2-heptyl-2,5,7,8-tetramethylchroman-6-ol (12) and 2,5,7,8-tetramethyl-2-(pent-l-enyl)chroman-6-ol (15). Methoxycarbonylmethyl 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylate (2) was formed by reaction of the triethylammonium salt of trolox (1) with methyl bromoacetate. Reaction of methoxycarbonylmethyltriphenylphosphonium bromide (16) with (8) did not produce the expected methyl 3-(6-benzyloxy-2,5,7,8-tetramethylchroman-2-yl)prop-2-enoate (17), but rather 4-(6-benzyloxy-2,5,7,8-tetramethylchroman-2-yl)but-3-en-2-one (22). A proposed mechanism for this unusual reaction is discussed.
- Suarna, Cacang,Dean, Roger T.,Southwell-Keely, Peter T.
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p. 1129 - 1135
(2007/10/03)
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- An easy access to symmetrical Z-olefins from phosphorus ylides
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Symmetrical Z-olefins are obtained in good to quantitative yields from phosphonium salts via an autoxidation process, in salt-free conditions.
- Poulain,Noiret,Patin
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p. 7703 - 7706
(2007/10/03)
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- Structure-activity relationship of α-galactosylceramides against b16- bearing mice
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Agelasphin-9b, (2S,3S,4R)-1-O-(α-D-galactopyranosyl)-16-methyl-2-[N- ((R)-2-hydroxytetracosanoyl)-amino]-1,3,4-heptadecanetriol, is a potent antitumor agent isolated from the marine sponge Agelas mauritianus. Various analogues of agelasphin-9b (a lead compound) were synthesized, and the relationship between their structures and biological activities was examined using several assay systems. From the results, KRN7000, (2S,3S,4R)-1-O-(α- D-galactopyranosyl)-2-(N-hexacosanoylamino)-1,3,4-octadecanetriol, was selected as a candidate for clinical application.
- Morita,Motoki,Akimoto,Natori,Sakai,Sawa,Yamaji,Koezuka,Kobayashi,Fukushima
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p. 2176 - 2187
(2007/10/02)
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- Cosalane and related compounds having activity against aids and aids-related infections
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Novel compounds having anti-HIV activity are disclosed along with formulations and methods for treating human immunodeficiency viral infections employing these compounds.
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- Amphiphilic Carbohydrate-Based Mesogens, VIII. A Facile Synthetic Route to Mesogenic L-ribo-1,2,3,4-Alkanetetrols
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The Wittig olefinations of 2,3-O-isopropylidene-D-ribofuranose (1) with two equivalents of alkylidenetriphenylphosphorane (alkylidene: hexylidene-undecylidene) followed by hydrogenation catalyzed by palladium on carbon and subsequent deprotection yield (2R,3S,4S-("L-ribo")-1,2,3,4-alkanetetrols 5.These amphiphiles form the smectic A mesophase on melting.However, when 1 is heated with one equivalent of the alkylidenetriphenylphosphoranes for longer periods, (2R,3S,4R)-("D-lyxo")-1,2,3,4-alkanetetrol-type products 4 predominate.Key Words: Liquis crystals / Carbohydrates / L-ribo-, D-lyxo-1,2,3,4-Alkanetetrols / Wittig olefination
- Dahlhoff, Wilhelm V.
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p. 109 - 114
(2007/10/02)
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- Studies on the Synthesis of Linear Aliphatic Compounds. Part. 3. The Synthesis of Paraffins with Very Long Chains
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The approach derived in Part 2 has been modified to increase the purity and yield of intermediates.The C12 starting materials have been doubled in chain length five times, and by using components of similar or different chain length in Wittig condensations ω-halogeno-acetals with 12n carbon atoms have been made up with n up to 32.They have been converted into paraffins with 102, 104, 150, 198, 246, 294, and 390 carbon atoms.Those paraffins with 150 or more carbon atoms show chain-folding in the crystalline state; this observation is contributing to the understanding of chain-folding behaviour long known in linear polyethylene but hitherto unknown in essentially pure paraffins.
- Bidd, Ilesh,Holdup, David W.,Whiting, Mark C.
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p. 2455 - 2464
(2007/10/02)
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- Racemic fluoro-substituted PGF2 α analogs
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This invention is racemic PGE2, racemic PGF2α, racemic PGF2β, racemic PGA2, racemic PGB2, analogs of those, and processes for making them. These compounds are useful for a variety of pharmacological purposes, including anti-ulcer, inhibiton of platelet aggregation, increase of nasal patency, abortion, and wound healing.
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- 3-Oxa prostaglandin Fα-type compounds
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This invention is a group of 3- and 4-oxa PG type compounds, and processes for making them. These compounds are useful for a variety of pharmacological purposes, including anti-ulcer, inhibition of platelet aggregation, increase of nasal patency, labor inducement at term, and wound healing.
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- Racemic prostaglandins of the 2-series and analogs thereof
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This invention is racemic PGE2, racemic PGF2α, racemic PGF2 β, racemic PGA2, racemic PGB2, analogs of those, and processes for making them. These compounds are useful for a variety of pharmacological purposes, including anti-ulcer, inhibition of platelet aggregation, increase of nasal patency, abortion, and wound healing.
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- Racemic prostaglandins of the 2-series and analogs thereof
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This invention is racemic PGE2, racemic PGF2α, racemic PGF2β, racemic PGA2, racemic PGB2, analogs of those, and processes of making them. These compounds are useful for a variety of pharmacological purposes, including anti-ulcer, inhibition of platelet aggregation, increase of nasal patency, abortion, and wound healing.
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- Racemic prostaglandins of the 2-series and analogs thereof
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This invention is racemic PGE2, racemic PGF2α, racemic PGF2α, racemic PGA2, racemic PGB2, analogs of those, and processes for making them. These compounds are useful for a variety of pharmacological purposes, including anti-ulcer, inhibition of platelet aggregation, increase of nasal patency, abortion, and wound healing.
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- Racemic fluoro-substituted PGE2 analogs
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This invention is racemic PGE2, racemic PGF2 α, racemic PGF2 β, racemic PGA2, racemic PGB2, analogs of those, and processes for making them. These compounds are useful for a variety of pharmacological purposes, including anti-ulcer, inhibition of platelet aggregation, increase of nasal patency, abortion, and wound healing.
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- Racemic prostaglandins of the 2-series and analogs thereof
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This invention is racemic PGE2, racemic PGF2 α, racemic PGF2 β, racemic PGA2, racemic PGB2, analogs of those, and processes for making them. These compounds are useful for a variety of pharmacological purposes, including anti-ulcer, inhibition of platelet aggregation, increase of nasal patency, abortion, and wound healing.
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- Racemic fluoro-substituted PGB2 analogs
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This invention is racemic PGE2 α, racemic PGF2α, racemic PGF2 β, racemic PGA2, racemic PGB2, analogs of those, and processes for making them. These compounds are useful for a variety of pharmacological purposes, including anti-ulcer, inhibition of platelet aggregation, increase of nasal patency, abortion, and wound healing.
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- Racemic prostaglandins of the 2-series and analogs thereof
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This invention is racemic PGE 2, racemic PGF 2 α, racemic PGF 2 β, racemic PGA 2, racemic PGB 2, analogs of those, and processes for making them. These compounds are useful for a variety of pharmacological purposes, including anti-ulcer, inhibition of platelet aggregation, increase of nasal patency, abortion, and wound healing.
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- Racemic prostaglandins of the 2-series and analogs thereof
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This invention is racemic PGE2, racemic PGF2α, racemic PGF2β, racemic PGA2, racemic PGB2, analogs of those, and processes for making them. These compounds are useful for a variety of pharmacological purposes, including anti-ulcer, inhibition of platelet aggregation, increase of nasal patency, abortion, and wound healing.
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