- Synthesis of Terminally Substituted 9-Alkylidene-10-methyl Acridans
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ω-Substituted undecanals 1 and 2 reacted with acridine derivatives 3 and 5 to give the terminally substituted 9-alkylidene-10-methylacridans 6.The compounds prepared were highly fluorescent and exhibited chemiluminescent activity. - Keywords: Acridans; Chemiluminescence.
- Varveri, Fannie S.,Nikokavouras, John,Mantaka-Marketou, Anastasia E.,Micha-Screttas, Maria
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- Synthesis of (Z/E)-11-tetradecen-1-ol, a component of Ostrinia nubilalis sex pheromone
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11-Tetradecen-1-ol acetate is a mixture of geometric isomers with the Z/E-conformations in a 94:6 ratio that is used as an attractant to trap corn pests. It has a powerful attractive action similar to that of an isomeric mixture of 11-tetradecenyl acetate with the Z/E-conformation in a 95:5 ratio that was extracted from the peritoneal cavity of male Ostrinia nubilalis Hubner in Xinjing (PRC).
- Li,Yong,Aisa
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- Synthesis and antibacterial evaluation of a new series of N-Alkyl-2-alkynyl/(E)-alkenyl-4-(1H)-quinolones
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To gain further insight into the structural requirements of the aliphatic group at position 2 for their antimycobacterial activity, some N-alkyl-4-(1H)-quinolones bearing position 2 alkynyls with various chain length and triple bond positions were prepared and tested for in vitro antibacterial activity against rapidly-growing strains of mycobacteria, the vaccine strain Mycobacterium bovis BCG, and methicillin-resistant Staphylococcus aureus strains, EMRSA-15 and -16. The compounds were also evaluated for inhibition of ATP-dependent MurE ligase of Mycobacterium tuberculosis. The lowest MIC value of 0.5 mg/L (1.2-1.5 μM) was found against M. fortuitum and M. smegmatis. These compounds displayed no or only weak toxicity to the human lung fibroblast cell line MRC-5 at 100 μM concentration. The quinolone derivatives exhibited pronounced activity against the epidemic MRSA strains (EMRSA-15 and -16) with MIC values of 2-128 mg/L 5.3-364.7 μM), and M. bovis BCG with an MIC value of 25 mg/L (66.0-77.4 μM). In addition, the compounds inhibited the MurE ligase of M. tuberculosis with moderate to weak activity showing IC50 values of 200-774 μM. The increased selectivity towards mycobacterial bacilli with reference to MRC-5 cells observed for 2-alkynyl quinolones compared to their corresponding 2-alkenyl analogues serves to highlight the mycobacterial specific effect of the triple bond. Exploration of a terminal bromine atom at the side chain of N-alkyl-2-(E)-alkenyl-4-(1H)-quinolones showed improved antimycobacterial activity whereas a cyclopropyl residue at N-1 was suggested to be detrimental to antibacterial activity.
- Wube, Abraham,Guzman, Juan-David,Huefner, Antje,Hochfellner, Christina,Blunder, Martina,Bauer, Rudolf,Gibbons, Simon,Bhakta, Sanjib,Bucar, Franz
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- Me3SI-promoted chemoselective deacetylation: a general and mild protocol
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A Me3SI-mediated simple and efficient protocol for the chemoselective deprotection of acetyl groups has been developedviaemploying KMnO4as an additive. This chemoselective deacetylation is amenable to a wide range of substrates, tolerating diverse and sensitive functional groups in carbohydrates, amino acids, natural products, heterocycles, and general scaffolds. The protocol is attractive because it uses an environmentally benign reagent system to perform quantitative and clean transformations under ambient conditions.
- Gurawa, Aakanksha,Kashyap, Sudhir,Kumar, Manoj
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p. 19310 - 19315
(2021/06/03)
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- Design, synthesis and antiparasitic evaluation of click phospholipids
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A library of seventeen novel ether phospholipid analogues, containing 5-membered heterocyclic rings (1,2,3-triazolyl, isoxazolyl, 1,3,4-oxadiazolyl and 1,2,4-oxadiazolyl) in the lipid portion were designed and synthesized aiming to identify optimised miltefosine analogues. The compounds were evaluated for their in vitro antiparasitic activity against Leishmania infantum and Leishmania donovani intracellular amastigotes, against Trypanosoma brucei brucei and against different developmental stages of Trypanosoma cruzi. The nature of the substituents of the heterocyclic ring (tail) and the oligomethylene spacer between the head group and the heterocyclic ring was found to affect the activity and toxicity of these compounds leading to a significantly improved understanding of their structure–activity relationships. The early ADMET profile of the new derivatives did not reveal major liabilities for the potent compounds. The 1,2,3-triazole derivative 27 substituted by a decyl tail, an undecyl spacer and a choline head group exhibited broad spectrum antiparasitic activity. It possessed low micromolar activity against the intracellular amastigotes of two L. infantum strains and T. cruzi Y strain epimastigotes, intracellular amastigotes and trypomastigotes, while its cytotoxicity concentration (CC50) against THP-1 macrophages ranged between 50 and 100 μM. Altogether, our work paves the way for the development of improved ether phospholipid derivatives to control neglected tropical diseases.
- Afroudakis, Pantelis,Barrias, Emile,Bifeld, Eugenia,Borsari, Chiara,Calogeropoulou, Theodora,Clos, Joachim,Costi, Maria Paola,Ellinger, Bernhard,Fotopoulou, Theano,Fragiadaki, Irini,Georgikopoulou, Kalliopi,Gul, Sheraz,Hachenberg, Julia,Kuzikov, Maria,Magoulas, George E.,Prousis, Kyriakos C.,Roussaki, Marina,Santarem, Nuno,Scoulica, Effie,Tejera Nevado, Paloma,da Silva, Anabela Cordeiro,de Souza, Wanderley
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- Highly Chemoselective Deprotection of the 2,2,2-Trichloroethoxycarbonyl (Troc) Protecting Group
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Nonreducing, pH-neutral conditions for the selective cleavage of the 2,2,2-trichloroethoxycarbonyl (Troc) protecting group are reported. Using trimethyltin hydroxide in 1,2-dichloroethane, Troc-protected alcohols, thiols, and amines can be selectively unmasked in the presence of various functionalities that are incompatible with the reducing conditions traditionally used to remove the Troc group. This mild deprotection protocol tolerates a variety of other hydrolytically sensitive and acid/base-sensitive moieties as well.
- Trost, Barry M.,Kalnmals, Christopher A.,Tracy, Jacob S.,Bai, Wen-Ju
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supporting information
p. 8043 - 8046
(2019/01/04)
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- Mn(0)-mediated chemoselective reduction of aldehydes. Application to the synthesis of α-deuterioalcohols
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A mild, simple, safe, chemoselective reduction of different kinds of aldehydes to the corresponding alcohols mediated by the Mn dust/water system is described. In addition to this, the use of D2O leads to the synthesis of α-deuterated alcohols and constitutes an efficient, inexpensive alternative for the preparation of these compounds.
- Jimenez, Tania,Barea, Elisa,Oltra, J. Enrique,Cuerva, Juan M.,Justicia, Jose
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experimental part
p. 7022 - 7025
(2010/11/18)
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- First syntheses of model long-chain trichloro[ω-(trimethylsilyl)alkynyl]silanes suitable for self-assembled monolayers on silicon surfaces
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The preparation of the title compounds involves the introduction of the required Me3SiC{triple bond, long}C and trichlorosilyl groups at the termini of the alkyl chain via derivatization of easily accessible and inexpensive materials/reagents. Trichloro[ω-(trimethylsilyl)alkynyl]silanes are useful for the linkage to a hydroxylated silicon surface for multilayer formation and for further chemical modification of the tail group of the monolayer.
- Banaszak, Estelle,Xu, Li-Wen,Bardeau, Jean-Fran?ois,Castanet, Anne-Sophie,Mortier, Jacques
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experimental part
p. 3961 - 3966
(2009/09/30)
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- A dehydrohalogenation methodology for synthesizing terminal olefins under mild conditions
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A new methodology for preparing terminal olefins in good yield by dehydrohalogenation of primary alkyl iodide with tetrabutylammonium fluoride in dimethyl sulfoxide at room temperature is presented. Optimization of the mild reaction conditions and assays on various alkyl iodides are described. Georg Thieme Verlag Stuttgart.
- Berube, Marie,Kamal, Fatima,Roy, Jenny,Poirier, Donald
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p. 3085 - 3091
(2008/02/08)
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- Multiple Electron Tunneling Paths across Self-Assembled Monolayers of Alkanethiols with Attached Ruthenium(II/III) Redox Centers
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Alkanethiol monolayers with pendant redox centers are deposited on gold electrodes by selfassembly.The monolayers are composed of both an electroactive thiol, HS(CH2)nC(O)NHCH2pyRu(NH3)5(2+/3+), with 10-15 methylene groups, and a diluent thiol, HS(CH2)mCOOH, also with 10-15 methylene groups.The monolayers are classified as "matched" (n = m), "exposed" ( n = 15, m = 10-14), and "buried" (n = 10, m = 11-15) according to the relative position of the redox center.Cyclic voltammograms in aqueous Na2SO4 indicate that the monolayers are close-packed with the redox centers residing in the aqueous phase in all but the most buried cases.Measurements of electron transfer kinetics by several methods (cyclic voltammetry, ac impedance spectroscopy, chronoamperometry) yield an internally consistent set of kinetic parameters, the standard rate constant ko, and the reorganization energy λ of the redox centers.The reorganization energies are in good agreement with the theoretically predicted value of 1.0 eV for the pyRu(NH3)5 redox centers.Plots of ln(ko) vs m are linear in all three cases.The slopes of the linear regression fit provide tunneling parameters (β, where ko ca. e-βm) of 0.97 +/- 0.03 (matched cases), 0,83 +/- 0.03 (exposed cases) and 0.16 +/- 0.02 (buried cases) per methylene.This pattern of β's is interpreted in terms of electronic coupling between the redox center and the electrode via both the redox thiol and the proximate diluent thiols, with the coupling via the diluent thiols dominating in the exposed cases.
- Finklea, Harry O.,Liu, Luna,Ravenscroft Melissa S.,Punturi, Sesto
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p. 18852 - 18858
(2007/10/03)
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- Sodium bis(2-methoxyethoxy)aluminium hydride in petroleum ether; a reagent for the selective reduction of brominated fatty esters to bromo alcohols
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The combination of NaH2Al(OCH2CH2OMe)2/petroleum ether was found to be highly effective for the selective reduction of long chain esters to alcohols in the presence of alkyl bromides.
- Wells, Andy
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p. 1143 - 1147
(2007/10/03)
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- Compounds
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Polymethacrylate polymers, pharmaceutical compositions containing them and their use in medicine as cholesterol lowering agents. A particular polymer of the invention is 11-N,N,N-trimethylammonioundecyl methacrylate chloride copolymer.
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- A New Synthetic Method of Macrocyclic Lactones from ω-Iodoalkylacrylates
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When the photostimulated cyclization reaction of ω-iodoalkylacrylates was performed in the presence of metal hydride complexes such as sodium cyanoborohydride (NaBH3CN), sodium borohydride (NaBH4) and potassium borohydride (KBH4), the corresponding macrocyclic lactones were produced.The use of NaBH3CN led to the highest yield of lactones.
- Abe, Motoji,Hayashikoshi, Takaoki,Kurata, Takeo
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p. 1789 - 1792
(2007/10/02)
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- Synthesis and Solid-State Polymerization of ω-(1,3-Butadiynyl) Substituted 1-Alkanol and Alkanoic Acid
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ω-(1,3-Butadiynyl) substituted 1-alkanol and alkanoic acid were synthesized and their polymerization behavior in crystals and in Langmuir-Blodgett (LB) films were investigated.Polymerization, using UV or γ-ray irradiation or thermal treatment, resulted in red- or golden-colored polymers.Since the absorption edge in the visible spectra of these polymers appeared at shorter wavelengths than those of the well known blue-colored polydiacetylenes, ?-conjugation is considered to be deteriorated to some extent.IR, X-ray diffraction, and solid-state 13C NMR measurements showed that the polymerization does not proceed in a single-crystal-to-single-crystal transition manner via regular 1,4-addition but with deterioration of the crystalline lattice.
- Okada, Shuji,Matsuda, Hiro,Otsuka, Masaaki,Kikuchi, Naoto,Hayamizu, Kikuko,et al.
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p. 455 - 461
(2007/10/02)
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- Hydroboration of functionalised olefins with acetoxyborohydride
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The acetoxyborohydride has been reported to hydroborate the C=C of functionalised olefins without effecting the functional group.
- Dhillon, Ranjit S.,Nayyar, Kaushal,Singh, Jasvinder
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p. 6015 - 6016
(2007/10/02)
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- PHOTOLACTONIZATION : A NOVEL SYNTHETIC ENTRY TO MACROLIDES
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o-Quinol acetates, hydroxyalkyalted at C(6), are easily accesible from simple phenols by Wessely acetoxylation (preferentially catalyzed by BF3).On UV irradiation ( in the presence of an appropriate tertiary amine), they are smoothly converted to macrocyclic lactones.Subtle conditions have been elaborated to lead to high overall yields, and the scope of the conversion of phenols to macrolides has been elucidated.
- Quinkert, Gerhard,Billhardt, Uta-Maria,Jakob, Harald,Fischer, Gerd,Glenneberg, Juergen,et al.
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p. 822 - 861
(2007/10/02)
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- SYNTHESIS OF 1,44-TETRATETRACONTANEDIOL
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The synthesis of the long-chain aliphatic diol 1,44-tetratetracontanediol was realized by chain growth in the Wurtz reation.Twofold condensation of the bifunctional fragments led to 1,44-tetratetracontanediol.Halogen-containing alcohols with protecting tetrahydrofuranyl and trimethylsilyl groups were used as starting compounds for the Wurtz condensation.
- Rusanova, E. E.,Sebyakin, Yu. L.,Volkova, L. V.,Evstigneeva, R. P.
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p. 248 - 251
(2007/10/02)
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- Sulfur-containing phospholipid compounds and therapeutic compositions
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Sulfur-containing phospholipid compounds of the formula STR1 pharmaceutical compositions having anti-tumor activity which include said phospholipid compounds, and the method of use for combating tumors, of said phospholipid compounds.
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- Process for the preparation of carbinols
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Organic compounds containing a carboxylic acid or carboxylic acid anhydride group are reduced when contacted with an alkali metal borohydride and a boron trihalide in a liquid medium in which diborane is soluble in the form of a labile borane adduct. Hydrolysis of the reaction mixture then provides a useful synthesis of the corresponding carbinols. The alkali metal borohydride-boron trihalide reagent may either be preformed and reacted subsequently with an organic compound containing a carboxylic acid or anhydride group, or the alkali metal borohydride-boron trihalide reagent may be produced in the presence of an organic compound containing a carboxylic acid or anhydride group. This development makes it possible to synthesize a wide variety of carbinols which are valuable and useful intermediates in organic synthesis.
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