- Synthesis of benzannulated N-heterocyclic carbene ligands by a template synthesis from 2-nitrophenyl isocyanide
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The reaction of 2-nitrophenyl isocyanide 2 with [M(CO)5(thf)] (M = Cr, Mo, W) yields the isocyanide complexes [M(CO)5(2)] (3: M = Cr; 4: M = Mo; 5: M = W). Complexes 3-5 react with elemental tin under reduction of the nitro function of the isocyanide ligand to give the complexes with the unstable 2-aminophenyl isocyanide ligand. The coordinated 2-aminophenyl isocyanide ligand in all three complexes reacts spontaneously under intramolecular nucleophilic attack of the primary amine at the isocyanide carbon atom to yield the complexes with the NH,NH-benzimidazol-2-ylidene ligand (6: M = Cr; 7: M = Mo; 8: M = W). An incomplete reduction of the nitro group in 3-5 is observed when hydrazine hydrate is used instead of tin. Here the formation of complexes with a coordinated 2-hydroxylamine-functionalized phenyl isocyanide [(CO)5M-CN-C6H4--2-N(H)-OH] is postulated and this unstable ligand again undergoes intramolecular cyclization to give the NH,NOH-stabilized benzimidazol-2-ylidene complexes 9-11. The tungsten derivative 11 can be allylated stepwise by a deprotonation/ alkylation sequence first at the OH and then at the NH position to yield the monoallylated and diallylated species 12 and 13. The molecular structures of 3-5 and 12-13 were established by X-ray crystallography.
- Hahn, F. Ekkehardt,Plumed, Cesar Garcia,Muender, Marco,Luegger, Thomas
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- Kinetic and mechanistic study of the atmospheric oxidation by OH radicals of allyl acetate
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A potential source of acetates, including allyl acetate, is combustion of esterified rape oil used as substitution fuel. This new formulation of diesel fuel significantly reduces the emission of particulate matter. To better evaluate the environmental impact of acetates, OH-induced oxidation kinetic and mechanism of allyl acetate were studied at room temperature and 1 atm using three environmental chambers (an indoor Teflon-film bag, an indoor Pyrex photoreactor, and the outdoor smog chamber EUPHORE. The main oxidation products were acetoxyacetaldehyde and formaldehyde. A mechanism was developed to describe the OH-induced oxidation of the acetate in the presence of NOx. Reaction with OH radicals was the main tropospheric fate of allyl acetate. When it reacted with OH radicals, it could contribute to the formation of photooxidants close to the emission sources. Acetoxyacetaldehyde yield was slightly smaller in the experiment at low NOx since some peroxides could be produced from peroxy radical + HO2 reaction and compete with the acetoxyacetaldehyde production.
- Picquet-Varrault,Fittschen,Doussin,Durand-Jolibois,Pirali,Carlier
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- Total synthesis of (±)-welwitindolinone A isonitrile
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A highly stereoselective total synthesis of the alkaloid natural product welwitindolinone A isonitrile has been completed. The synthesis utilizes a chloronium ion mediated semi-pinacol rearrangement to simultaneously install the C10 quaternary center and neopentyl chlorine and a novel anionic cyclization to construct the spiro-oxindole with complete stereocontrol. Copyright
- Reisman, Sarah E.,Ready, Joseph M.,Hasuoka, Atsushi,Smith, Catherine J.,Wood, John L.
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- Diversity oriented synthesis: Concise entry to novel derivatives of Yohimbine and Corynanthe alkaloids
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A novel MCAP-cycloaddition sequence has been applied to the facile synthesis of β-carboline intermediates to gain rapid access to novel derivatives of Yohimbine-like and Corynanthe-like compounds that may be easily diversified by cross-coupling reactions
- Wang, Zhiqian,Kaneda, Kyosuke,Fang, Zhenglai,Martin, Stephen F.
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- Linear 6,6′-biazulenyl framework featuring isocyanide termini: Synthesis, structure, redox behavior, complexation, and self-assembly on Au(111)
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The key step in accessing the title species (5), the first nonbenzenoid diisocyanobiaryl, involved an unexpected homocoupling of a 6-bromoazulene derivative. The reversible 2e- reduction of 5 was addressed electrochemically and computationally. The shifts in energies of the S 0→S1 and S0→S2 transitions for a series of related 6,6′-biazulenyl derivatives correlate with the e--donating/-withdrawing strength of their 2,2′-substituents but follow opposite trends. Species 5 adsorbs end-on (η1) to the Au(111) surface via one of its -NC groups to form a 2-nm-thick film. In addition, bimetallic coordination of 5's -NC termini can be readily achieved.
- Maher, Tiffany R.,Spaeth, Andrew D.,Neal, Brad M.,Berrie, Cindy L.,Thompson, Ward H.,Day, Victor W.,Barybin, Mikhail V.
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- Welwitindolinone C synthetic studies. Construction of the welwitindolinone carbon skeleton via a transannular nitrone cycloaddition
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Described is the construction of the N-methylwelwitindolinone C core via an efficient strategy that employs a sequential rhodium carbenoid-mediated O-H insertion, Claisen rearrangement and transannular [3+2] nitrone cycloaddition.
- Freeman, David B.,Holubec, Alexandra A.,Weiss, Matthew W.,Dixon, Julie A.,Kakefuda, Akio,Ohtsuka, Masami,Inoue, Munenori,Vaswani, Rishi G.,Ohki, Hidenori,Doan, Brian D.,Reisman, Sarah E.,Stoltz, Brian M.,Day, Joshua J.,Tao, Ran N.,Dieterich, Noah A.,Wood, John L.
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- Reactions of OH and Cl with isopropyl formate, isobutyl formate, n-propyl isobutyrate and isopropyl isobutyrate
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The rate coefficients for the reactions of OH with isopropyl formate, isobutyl formate, n-propyl isobutyrate and isopropyl isobutyrate have been determined using both absolute and relative methods. The relative rate method has been also used to measure the room temperature rate coefficient for the reaction of Cl with the same esters. In addition, a series of runs conducted on the OH-initiated oxidation of isopropyl formate, isobutyl formate and n-propyl isobutyrate showed the formation of acetone from the three reactions. The formation of propanal was also observed for n-propyl isobutyrate.
- Zhang,Liang,Jiang,Cazaunau,Da?le,Mu,Mellouki
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- An efficient approach to the stereocontrolled synthesis of enamides
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A fast, flexible, and efficient approach for the stereocontrolled synthesis of enamides has been developed starting from lactams and amides through the use of imides. This new approach provides access to enamide systems not easily or currently accessible through other approaches.
- Villa, Mathew V. J.,Targett, Sarah M.,Barnes, John C.,Whittingham, William G.,Marquez, Rodolfo
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- Coordination-Driven Self-Assembly of Cyclometalated Iridium Squares Using Linear Aromatic Diisocyanides
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Here, we demonstrate facile [4 + 4] coordination-driven self-assembly of cyclometalated iridium(III) using linear aryldiisocyanide bridging ligands (BLs). A family of nine new [Ir(C^N)2(μ-BL)]44+ coordination cages is described, where C^N is the cyclometa
- Olumba, Morris E.,Na, Hanah,Friedman, Alan E.,Teets, Thomas S.
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- A novel synthesis of substituted 3-amino and 3-thio pyrimido[5,4-e]-1,2,4-triazine-5,7(1H,6H)-diones
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Fervenulin is a natural product that has been extensively studied due to its molecular features and breadth of biological activities. Published studies have reported the generation of numerous analogues of the bicyclic pyrimidotriazinodione core. One underrepresented subclass are compounds with electron releasing atoms bonded directly to the C-3 position. We report an efficient and straightforward synthesis of compounds with substituted amino and thio functionality attached to the C-3 position. These are derived from a common 3-chloro precursor that is made in six steps in 15.8% overall yield from a starting chlorouracil. Our methodology should be applicable to the synthesis of C-3 ether congeners also, and through previously described chemistry be expandable to incorporating diversity at the N-6 position of the pyrimidotriazinodione core. The chemistry reported herein expands possibilities for the generation of diverse libraries of substituted pyrimidotriazinediones for future studies.
- Xu, Hao,Powelson, Ian A.,Jin, Yafei,Showalter, Hollis D.
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- 3-Amino-β-carboline derivatives and the benzodiazepine receptor. Synthesis of a selective antagonist of the sedative action of diazepam
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Seven 3-N-substituted derivatives of 3-amino-β-carboline were synthesized and their affinities for the benzodiazepine receptor were assessed in vitro. Two compounds, 3-(ethylamino)-β-carboline and 3-[(methoxycarbonyl)amino]-β-carboline (β-CMC), showing IC50 values of 460 and 71 nM, respectively, were selected for in vivo studies. The former compound showed long-lasting proconvulsant activity in Papio papio baboons while β-CMC was shown in mice to selectively antagonize the sedative effects of diazepam without exhibiting convulsant, proconvulsant, or anxiogenic activity by itself.
- Dodd,Ouannes,Prado de Carvalho,Valin,Venault,Chapouthier,Rossier,Potier
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- Synthesis of 5-halogeno-6-amino-2'-deoxyuridines and their analogs as potential inhibitors of thymidine phosphorylase
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5-Halogeno-6-amino-2'-deoxyuridines were synthesized from 2'- deoxyuridine as potential thymidine phosphorylase (ThdPase) inhibitors. Among the compounds synthesized, 5-bromo-6-amino-2'-deoxyuridine (6) and 5-iodo-6- amino-2'-deoxyuridine (9) were found to inhibit ThdPase activity with IC50 values of 1.3 μM and 6.5 μM, respectively. In vitro cell culture studies showed that compound (6) can significantly enhance the cytotoxic effects of 5-fluoro-2'-deoxyuridine against a human colon cancer HCT-8 cell line.
- Pan, Bai-Chuan,Chen, Zhi-Hao,Chu, Edward,Chu, Ming-Yu Wang,Chu, Shih-Hsi
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- Formic acetic anhydride in the gas phase, studied by electron diffraction and infrared spectroscopy, supplemented with ab-initio calculations of geometries and force fields
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The structure of formic acetic anhydride was studied by the joint analysis of gas-phase electron diffraction and infrared data, supported with extensive ab-initio calculations on the 4-21G and 6-31G** levels. All data agree with the gas phase at room temperature existing in the planar (sp,ap) conformer. Best electron diffraction geometry was obtained using geometrical constraints derived from 4-21G calculations after correction to rα level. Also, the scaled 4-21G force field performed better than its 6-31G** counterpart. The new model of formic acetic anhydride is self-consistent, reproduces the IR frequencies with a root-mean-square deviation of 8.8 cm-1, and results in an improved frequency assignment as well as in a good qualitative agreement between observed and calculated IR band intensities. Formic acetic anhydride is conformationally and spectroscopically very different from acetic anhydride, but strongly resembles formic anhydride, although differences remain. The similarities with formic anhydride are ascribed to an attractive nonbonded H (formyl)...O= interaction, while the dissimilarities are ascribed to a larger electronic interaction between two formyl moieties rather than between a formyl and an acetyl moiety.
- Wu,Shlykov,Van Alsenoy,Geise,Sluyts,Van Der Veken
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- Selective JAK1 inhibitor compound as well as preparation method and application thereof
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The invention provides a heterocyclic compound serving as a JAK1 inhibitor and synthesis and use methods, and particularly provides a compound shown as a formula (I), a preparation method of the compound and application of the compound serving as a JAK1 i
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Paragraph 0252-0253; 0254-0255
(2021/01/30)
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- Rhodium-Catalyzed Regioselective Hydroformylation of Alkynes to α,β-Unsaturated Aldehydes Using Formic Acid
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A rhodium-catalyzed hydroformylation of alkynes with formic acid was developed. The method provides α,β-unsaturated aldehydes in high yield and E-selectivity without the need to handle toxic CO gas.
- Fan, Chao,Hou, Jing,Chen, Yu-Jia,Ding, Kui-Ling,Zhou, Qi-Lin
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supporting information
p. 2074 - 2077
(2021/04/05)
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- Enhancing the chemosensitivity of HepG2 cells towards cisplatin by organoselenium pseudopeptides
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Despite all recent advances in the treatment of hepatocellular carcinoma (HCC), chemotherapy resistance still represents a major challenge in its successful clinical management. Chemo-sensitization offers an attractive strategy to counter drug resistance. Herein we report the identification of novel organoselenium-based pseudopeptides as promising highly effective chemo-sensitizers in treating HCC with cisplatin. A series of functionalized pseudopeptide- (5–9 and 17–19), peptidomimetic- (10–12 and 20–23), and tetrazole-based (13–16 and 24–27) organoselenium compounds were synthesized via isonitrile-based multicomponent reactions from two novel selenium-containing isocyanides. All compounds were evaluated for their cytotoxicity against HepG2 and the non-cytotoxic doses were used to restor the sensitivity of the cells to cisplatin. New organoselenium compounds (7, 9, 15, or 23) led to an effective chemo-sensitization of HepG2 cells towards cisplatin (up-to 27-fold). Cell cycle studies indicate that the most potent peptidomimetic diselenide 23 arrested cells at the S phase and induced apoptosis via ROS modulation.
- Shaaban, Saad,Shabana, Sameh M.,Al-Faiyz, Yasair S.,Manolikakes, Georg,El-Senduny, Fardous F.
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- Photooxidation Reactions of Ethyl 2-Methylpropionate (E2MP) and Ethyl 2,2-Dimethylpropionate (E22DMP) Initiated by OH Radicals: An Experimental and Computational Study
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The relative rate (RR) technique was used for the measurement of OH-initiated photooxidation reactions of ethyl 2-methylpropionate (E2MP) and ethyl 2,2-dimethylpropionate (E22DMP) in the temperature range of 268-363 K at 760 Torr. In addition to this, the
- Kaipara, Revathy,Rajakumar, B.
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p. 2768 - 2784
(2020/05/08)
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- AMINO HETEROCYCLIC COMPOUNDS AND USES THEREOF
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The present disclosure relates to compounds of Formula (I): and to their pharmaceutically acceptable salts, pharmaceutical compositions, methods of use, and methods for their preparation. The compounds disclosed herein are useful for inhibiting the maturation of cytokines of the IL-1 family by inhibiting inflammasomes and may be used in the treatment of disorders in which inflammasome activity is implicated, such as inflammatory, autoinflammatory, and autoimmune diseases and cancers.
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Paragraph 01310
(2020/08/22)
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- A novel approach to oxazole-containing diterpenoid synthesis from plant roots: Salviamines e and F
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In this study, salviamines E and F, which are structurally unique abietane-type diterpene alkaloids containing an oxazole ring, were efficiently synthesized from a known molecule, 5,7,8-trimethoxy-1-naphthol. The synthetic sequence involves the following crucial steps: (i) the assembly of a carbon skeleton by coupling a six-carbon homoprenyl unit with a naphthalene moiety (Kumada-Tamao-Corriu coupling); (ii) the construction of a tricyclic phenanthrene ring by acid-induced cyclization of a naphthalene derivative with a homoprenyl side chain; (iii) the formation of an oxazole ring by nucleophilic ring closure of a 2-aminophenylene-1,4-diyl-diformate or -diacetate moiety and (iv) Friedel-Crafts acetylation at the C13 position of the tetracyclic intermediates to obtain the two target molecules, salviamines E and F. To the best of our knowledge, salviamine synthesis is reported here for the first time.
- Narita, Koichi,Fujisaki, Narumi,Sakuma, Yuta,Katoh, Tadashi
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p. 655 - 663
(2019/01/24)
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- Sulfonium Salts as Alkylating Agents for Palladium-Catalyzed Direct Ortho Alkylation of Anilides and Aromatic Ureas
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A novel method for the ortho alkylation of acetanilide and aromatic urea derivatives via C-H activation was developed. Alkyl dibenzothiophenium salts are considered to be new reagents for the palladium-catalyzed C-H activation reaction, which enables the transfer of methyl and other alkyl groups from the sulfonium salt to the aniline derivatives under mild catalytic conditions.
- Simkó, Dániel Cs.,Elekes, Péter,Pázmándi, Vivien,Novák, Zoltán
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supporting information
p. 676 - 679
(2018/02/09)
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- DIHYDROQUINOLIZINONES AS ANTIVIRALS
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Compounds, specifically hepatitis B virus and/or hepatitis D virus inhibitors, more specifically compounds that inhibit HBe antigen and HBs antigen in a subject, for the treatment of viral infections, and methods of preparing and using such compounds. Formula (I):
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Paragraph 00597; 00615; 00616
(2018/09/19)
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- Novel Asymmetric Formylation of Aromatic Compounds: Enantioselective Synthesis of Formyl 7,8-Dipropyltetrathia[7]helicenes
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Asymmetric formylation of aromatic compounds is virtually unexplored. We report the synthesis and evaluation of a library including 20 new chiral formamides in the kinetic resolution of 7,8-dipropyltetrathia[7]helicene, affording the corresponding formyl- or diformylhelicenes in up to 73% ee, making enantiopure compounds available by recrystallisation. With the N,N-disubstituted formamides used in this study, the best enantioselectivity has been achieved with R1=iPr, R2=Me, R3=H, R4=1-naphthyl or its 1-pyrenyl equivalent. Why have chiral formamides been overlooked for so long as tools in asymmetric synthesis? Herein new and efficient procedures are described in which enantioselective delivery of the formyl group achieves kinetic resolution and double kinetic resolution of helicenes, a class of chiral fused aromatic structures that are notoriously difficult to prepare in enantiopure form.
- Doulcet, Julien,Stephenson, G. Richard
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supporting information
p. 13431 - 13436
(2015/09/15)
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- PROCESSES FOR PREPARING ANTIVIRAL COMPOUNDS
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The present disclosure provides processes for the preparation of a compound of formula: which is useful as an antiviral agent. The disclosure also provides compounds that are synthetic intermediates.
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Paragraph 0424-0425
(2015/12/30)
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- A recyclable CO surrogate in regioselective alkoxycarbonylation of alkenes: Indirect use of carbon dioxide
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Herein, we report a Pd-catalysed alkoxycarbonylation of alkenes based on the use of a recyclable CO2 reduction product, the crystalline and air-stable N-formylsaccharin, as a CO surrogate. The carbonylation proceeds under ambient conditions in an exceptionally complementary regioselective fashion yielding the desired branched products from styrene derivatives and valuable linear esters from alkyl-substituted alkenes.
- Gehrtz,Hirschbeck,Fleischer
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supporting information
p. 12574 - 12577
(2015/08/06)
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- Tropospheric chemical degradation of vinyl and allyl acetate initiated by Cl atoms under high and low NOx conditions
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The products of the reactions of Cl atoms with vinyl acetate (VA) and allyl acetate (AA) have been investigated in a 1080 L chamber using in situ FTIR. The experiments were performed at 296 K and atmospheric pressure of synthetic air in the presence and in the absence of NOx. For the reaction of Cl with VA in the presence of NOx formic acetic anhydride, acetic acid and formyl chloride are the major reaction products. In the absence of NOx, the yields of these products are significantly reduced and formation of the carbon-chain-retaining compound CH3C(O)OC(O)CH2Cl is observed. For the reaction of Cl with AA in the presence of NOx acetoxyacetaldehyde and formaldehyde were observed as the main products. In contrast, without NOx, the observations support that the major reaction pathway is the formation of the carbon-chain-retaining compound CH3C(O)OCH2C(O)CH2Cl. The reaction mechanisms leading to the products are discussed. The formation of the high yields of formyl chloride and formaldehyde in the reactions of Cl with VA and AA, respectively, are at odds with currently accepted mechanistic pathways.
- Blanco, María B.,Bejan, Iustinian,Barnes, Ian,Wiesen, Peter,Teruel, Mariano A.
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p. 48154 - 48163
(2015/06/16)
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- Design and synthesis of alkoxyindolyl-3-acetic acid analogs as peroxisome proliferator-activated receptor-γ/δ agonists
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A series of carbazole or phenoxazine containing alkoxyindole-3-acetic acid analogs were prepared as PPARγ/δ agonists and their transactivation activities for PPAR receptor subtypes (α, γ and δ) were investigated. Structure-activity relationship studies disclosed the effect of the lipophilic tail, attaching position of the alkoxy group and N-benzyl substitution at indole. Compound 1b was the most potent for PPARδ and 3b for PPARγ. Molecular modeling suggested two different binding modes of our alkoxyindole-3-acetic acid analogs providing the insight into their PPAR activity.
- Gim, Hyo Jin,Li, Hua,Lee, Eun,Ryu, Jae-Ha,Jeon, Raok
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supporting information
p. 513 - 517
(2013/02/25)
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- Water-soluble chiral polyisocyanides showing thermoresponsive behavior
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To afford chiral polyisocyanides with thermoresponsiveness may open new gates to enhance their functionality and to broaden their applications. Herein, we report the synthesis of a series of novel polyisocyanides carrying oligoethylene glycols (OEGs) modified dipeptides as the pendent groups. These polyisocyanides not only show different chiroptical properties but also possess characteristic thermoresponsive behavior. The corresponding monomers carrying different OEG units in the periphery are water-soluble, thus allowing their polymerization feasible in aqueous medium with NiCl2 as the catalyst. For comparison, polyisocyanides were also prepared in organic solvents, such as dichloromethane and tetrahydrofuran. The effects of solvent and polymerization temperature as well as chemical structures of the pendants on the chiroptical properties of the resulting polymers were examined. The characteristic thermoresponsive behavior of these chiral polymers was investigated by 1H NMR spectroscopy and turbidity measurements using UV/vis spectroscopy. The thermally induced aggregation processes were also followed by dynamic light scattering. It was found that the phase transition temperatures of these polymers were significantly influenced not only by the overall hydrophilicity but also by their secondary structures.
- Hu, Guixia,Li, Wen,Hu, Yulong,Xu, Anqiu,Yan, Jiatao,Liu, Lianxiao,Zhang, Xiacong,Liu, Kun,Zhang, Afang
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p. 1124 - 1132
(2013/04/10)
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- A fluorous and click approach for screening potential PET probes: Evaluation of potential hypoxia biomarkers
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Radiopharmaceuticals for nuclear imaging are essentially targeting molecules, labeled with short-lived radionuclides (e.g., F-18 for PET). A significant drawback of radiopharmaceuticals development is the difficulty to access radiolabeled molecule libraries for initial in vitro evaluation, as radiolabeling has to be optimized for each individual molecule. The present paper discloses a method for preparing libraries of 18F-labeled radiopharmaceuticals using both the fluorous-based 18F-radiochemistry and the Huisgen 1,3-dipolar (click) conjugation reaction. As a proof of concept, this approach allowed us to obtain a series of readily accessible 18F-radiolabeled nitroaromatic molecules, for exploring their structure-activity relationship and further in vitro evaluation of their hypoxic selectivity.
- Bejot, Romain,Carroll, Laurence,Bhakoo, Kishore,Declerck, Jér?me,Gouverneur, Veronique
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supporting information; experimental part
p. 324 - 329
(2012/03/10)
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- Acyl derivatives of boswellic acids as inhibitors of NF-κB and STATs
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Boswellic acid acylates including their epimers were synthesized and screened against a panel of human cancer cell lines. They exhibited a range of cytotoxicity against various human cancer cell lines thereby leading to the development of a possible SAR. One of the identified lead compounds was found to be an inhibitor of the NF-κB and STAT proteins, warranting further investigations to be developed into a potential anticancer lead.
- Kumar, Ajay,Shah, Bhahwal A.,Singh, Samar,Hamid, Abid,Singh, Shashank K.,Sethi, Vijay K.,Saxena, Ajit K.,Singh, Jaswant,Taneja, Subhash C.
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supporting information; body text
p. 431 - 435
(2012/03/11)
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- Formylated polyamines as peptidomimetics
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A new construct for imitating a natural peptide ligand using a modified retro-inverso sequence is described. It is demonstrated through the synthesis of a peptidomimetic derived from the endogenous sequence of leucine enkephalin. The product was active at 400 nM and selective for μ-opioid receptors.
- Javor, Sacha,Janowsky, Aaron,Johnson, Robert,Wolfrum, Katherine,Tadayoni-Rebek, Mitra,Rebek Jr., Julius
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supporting information
p. 6580 - 6582
(2013/01/14)
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- Total synthesis of (-)-salinosporamide A
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A concise and stereoselective total synthesis of (-)-salinosporamide A (1), a potent inhibitor of the 20S proteasome that is in clinical development as an anticancer drug candidate, has been accomplished in 14 steps with 19% overall yield from 4-pentenoic acid. Our synthesis features a stereoselective alkylation utilizing a chiral auxiliary, formation of a pyrrolidine unit, and oxidation of the pyrrolidine to a γ-lactam. To demonstrate the scalability of our synthesis, (-)-salinosporamide A has been synthesized on a gram scale.
- Satoh, Nobuhiro,Yokoshima, Satoshi,Fukuyama, Tohru
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supporting information; experimental part
p. 3028 - 3031
(2011/08/06)
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- N-Formylsaccharin: A new formylating agent
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N-Formylsaccharin, a very cheap reagent, has been revealed to be an efficient and chemoselective formylating agent of amines. Georg Thieme Verlag Stuttgart New York.
- Cochet, Thomas,Bellosta, Véronique,Greiner, Alfred,Roche, Didier,Cossy, Janine
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experimental part
p. 1920 - 1922
(2011/10/02)
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- A domino microwave-assisted protocol for the synthesis of 2,6-disubstituted pyrimidinones
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A practical microwave-assisted protocol for the synthesis of 2,6-disubstituted pyrimidinones has been developed. This approach is based on a domino Michael addition-cyclocondensation reaction between substituted thioureas/guanidines and acetylenecarboxyla
- Radi, Marco,Casaluce, Gianni,Botta, Maurizio
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supporting information; experimental part
p. 1997 - 2000
(2011/10/09)
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- Synthesis, photophysical properties, and molecular aggregation of gold(I) complexes containing carbon-donor ligands
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A series of gold(I) complexes with N-heterocyclic carbene (NHC) and acetylide ligands, namely [Au(NHC1)(C≡CAr)] (NHC 1=1-(9-anthracenylmethyl)-3-(n)-butylimidazol-2-ylidene; 1b-1g), [Au(NHC2)(C≡CAr)] (NHC2=1,3-diethylimidazol-2- ylidene; 2b-2f) and [Au(C≡NAr)2]+ (C≡NAr=arylisocyanide; 3a-3f) have been synthesized. At room temperature, most of these gold(I) complexes are emissive in the solid state and in solutions with lifetimes in the nanosecond to submicrosecond regime. The emissions of complexes 1b-1g in solutions are assigned to 1π-π* excited states of the NHC ligand, while that of 2b-2f and 3a-3f are phosphorescent in nature. The intriguing solvatochromism of complex 3a was also investigated. Complexes 1b, 1d, 3a, and 3e aggregate into crystalline nanowires in freshly prepared THF/water dispersions. The X-ray crystallographic data reveal that 1b and 1d possess intermolecular π-π and C-H ... π interactions; while 3a was found to display intermolecular gold(I) ... π interactions. Copyright
- Chow, Andy Lok-Fung,So, Man-Ho,Lu, Wei,Zhu, Nianyong,Che, Chi-Ming
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supporting information; experimental part
p. 544 - 553
(2011/10/12)
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- Acid-induced conformational alteration of cis-preferential aromatic amides bearing N-methyl-N-(2-pyridyl) moiety
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A series of cis-preferential aromatic N-methyl amides was designed and synthesized, and acid-induced conformational alteration of these compounds was investigated by means of NMR measurements in solution and X-ray crystal structure analysis. Compounds with a terminal N-methyl-N-(2-pyridyl) amide unit showed acid-induced conformational change from cis to trans, while those with a terminal N-methyl-2-pyridinecarboxamide unit showed a change of the carbonyl orientation from anti to syn with retention of cis conformation.
- Okamoto, Iwao,Terashima, Masayuki,Masu, Hyuma,Nabeta, Mayumi,Ono, Kaori,Morita, Nobuyoshi,Katagiri, Kosuke,Azumaya, Isao,Tamura, Osamu
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experimental part
p. 8536 - 8543
(2011/11/28)
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- Aminothiazolomorphinans with mixed κ and μ opioid activity
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A series of N-substituted and N′-substituted aminothiazole-derived morphinans (5) were synthesized for expanding the structure-activity relationships of aminothiazolo-morphinans. Although their affinities were somewhat lower thn their prototype aminothiazolo-N-cyclopropylmorphinan (3), 3-aminothiazole derivatives of cyclorphan (1) containing a primary amino group displayed high affinity and selectivity at the κ and μ opioid receptors. [35S]GTPγS binding assays showed that the aminothiazolomorphinans were κ agonists with mixed agonist and antagonist activity at the μ opioid receptor. These novel N′-monosubstituted aminothiazole-derived morphinans may be valuable for the development of drug abuse medications.
- Zhang, Tangzhi,Yan, Zhaohua,Sromek, Anna,Knapp, Brian I.,Scrimale, Thomas,Bidlack, Jean M.,Neumeyer, John L.
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experimental part
p. 1903 - 1913
(2011/06/11)
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- Atmospheric chemistry of two biodiesel model compounds: Methyl propionate and ethyl acetate
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The atmospheric chemistry of two C4H8O2 isomers (methyl propionate and ethyl acetate) was investigated. With relative rate techniques in 980 mbar of air at 293 K the following rate constants were determined: k(C2H5C(O)OCH3 + Cl) = (1.57 ± 0.23) × 10-11, k(C2H5C(O) OCH3 + OH) = (9.25 ± 1.27) × 10-13, k(CH 3C(O)OC2H5 + Cl) = (1.76 ± 0.22) × 10-11, and k(CH3C(O)OC2H5 + OH) = (1.54 ± 0.22) × 10-12 cm3 molecule -1 s-1. The chlorine atom initiated oxidation of methyl propionate in 930 mbar of N2/O2 diluent (with, and without, NOx) gave methyl pyruvate, propionic acid, acetaldehyde, formic acid, and formaldehyde as products. In experiments conducted in N 2 diluent the formation of CH3CHClC(O)OCH3 and CH3CCl2C(O)OCH3 was observed. From the observed product yields we conclude that the branching ratios for reaction of chlorine atoms with the CH3-, -CH2-, and -OCH3 groups are 9 ± 2%, respectively. The chlorine atom initiated oxidation of ethyl acetate in N2/O 2 diluent gave acetic acid, acetic acid anhydride, acetic formic anhydride, formaldehyde, and, in the presence of NOx, PAN. From the yield of these products we conclude that at least 41 ± 6% of the reaction of chlorine atoms with ethyl acetate occurs at the -CH2- group. The rate constants and branching ratios for reactions of OH radicals with methyl propionate and ethyl acetate were investigated theoretically using transition state theory. The stationary points along the oxidation pathways were optimized at the CCSD(T)/cc-pVTZ//BHandHLYP/aug-cc-pVTZ level of theory. The reaction of OH radicals with ethyl acetate was computed to occur essentially exclusively (～99%) at the -CH2- group. In contrast, both methyl groups and the -CH2- group contribute appreciably in the reaction of OH with methyl propionate. Decomposition via the α-ester rearrangement (to give C2H5C(O)OH and a HCO radical) and reaction with O 2 (to give CH3CH2C(O)OC(O)H) are competing atmospheric fates of the alkoxy radical CH3CH2C(O)OCH 2O. Chemical activation of CH3CH2C(O)OCH 2O radicals formed in the reaction of the corresponding peroxy radical with NO favors the α-ester rearrangement.
- Andersen, Vibeke F.,Berhanu, Tesfaye A.,Nilsson, Elna J. K.,Jorgensen, Solvejg,Nielsen, Ole John,Wallington, Timothy J.,Johnson, Matthew S.
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experimental part
p. 8906 - 8919
(2011/10/17)
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- Titanocene-promoted eliminations on epoxy alcohols and epoxy esters
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The reaction of a series of 2,3-epoxy alcohols and the corresponding formates, acetates, and benzoates promoted by Cp2TiCl has been studied. The different outcome of the reaction of epoxy derivatives has been rationalized in terms of mechanistically biased processes. After homolytic oxirane cleavage, four main types of reaction were found: dehydroxylation, decarboxylation, dehydrogenation, and deoxygenation. The reaction products varied according to the substitution pattern. The radical nature of these eliminations is demonstrated.
- Fernandez-Mateos, Alfonso,Madrazo, Soledad Encinas,Teijon, Pablo Herrero,Gonzalez, Rosa Rubio
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supporting information; experimental part
p. 856 - 861
(2010/04/05)
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- Total synthesis of the lycorenine-type amaryllidaceae alkaloid (±)-Clivonine via a biomimetic ring-switch from a lycorine-type progenitor
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A fully diastereoselective total synthesis of the lycorenine-type Amaryllidaceae alkaloid (±)-clivonine (19) is reported via a route that employs for the first time a biomimetic ring-switch from a lycorine-type progenitor, thereby corroborating experimentally the biogenetic hypothesis first expounded for these compounds by Barton in 1960.
- Giro Mannas, Carles,Paddock, Victoria L.,Bochet, Christian G.,Spivey, Alan C.,White, Andrew J. P.,Mann, Inderjit,Oppolzer, Wolfgang
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supporting information; experimental part
p. 5176 - 5178
(2010/06/18)
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- Bis(oxazolines) based on glycopyranosides - Steric, configurational and conformational influences on stereoselectivity
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In previous studies we found that the asymmetric induction of bis(oxazolines) based on D-glucosamine strongly depended on the steric demand of the 3-O-substituents. To further probe the impact of the 3-position of the pyranose scaffold, we prepared 3-epimerised and 3-defunctionalised versions of these ligands as well as a 3-O-formyl derivative. Application of these new ligands in asymmetric cyclopropanation revealed strong steric and configurational effects of position 3 on asymmetric induction, further dramatic effects of the pyranose conformation were also observed.
- Minuth, Tobias,Boysen, Mike M. K.
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supporting information; experimental part
(2010/07/18)
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- CYCLIC INHIBITORS OF 11 β-HYDROXYSTEROID DEHYDROGENASE 1
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This invention relates to novel compounds of the Formula Formulas (I), (Ia1-20), (Ib1-20), (Ic1-20), pharmaceutically acceptable salts thereof, and pharmaceutical compositions thereof, which are useful for the therapeutic treatment of diseases associated with the modulation or inhibition of 11β-HSD1 in mammals. The invention further relates to pharmaceutical compositions of the novel compounds and methods for their use in the reduction or control of the production of cortisol in a cell or the inhibition of the conversion of cortisone to cortisol in a cell.
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Page/Page column 52
(2010/08/18)
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- Synthesis of 2-Boryl- and silylindoles by copper-catalyzed borylative and silylative cyclization of 2-alkenylaryl isocyanides
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(Figure Presented) We have developed a method for the synthesis of 2-borylindoles via the copper(I)-catalyzed borylative cyclization of 2-alkenylphenyl isocyanides using diboronate. The reaction proceeds at room temperature under neutral conditions and exhibits high tolerance to functional groups, such as Br, CO2R, COR, CONMe2, and CN. The 2-borylindoles synthesized in the present study can be elaborated into an array of indole-based derivatives, for example, through the Suzuki-Miyaura reaction. The utility of this method is demonstrated in the rapid synthesis of a kinase inhibitor, paullone. The reaction can be extended to the synthesis of 2-hydride indole and 2-silylindole by using hydroboronate (or hydrosilane) and silylboronate, respectively. Under these copper-catalyzed conditions, a quinoxaline ring system can also be constructed by using 1,2-isocyanobenzene as a substrate.
- Tobisu, Mamoru,Fujihara, Hirokazu,Koh, Keika,Chatani, Naoto
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supporting information; experimental part
p. 4841 - 4847
(2010/10/19)
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- Photoaffinity-labeled peptoids and depsipeptides by multicomponent reactions
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Photoaffinity tags can be incorporated easily into peptoids and congeners by the Ugi and Passerini multicomponent reactions. Products related to photo-methionine and photo-leucine can be accomplished by diazirine-containing building blocks. The same proto
- Henze, Michael,Kreye, Oliver,Brauch, Sebastian,Nitsche, Christoph,Naumann, Kai,Wessjohann, Ludger A.,Westermann, Bernhard
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experimental part
p. 2997 - 3003
(2010/10/21)
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- Merging nucleophilic and hydrogen bonding catalysis: An anion binding approach to the kinetic resolution of propargylic amines
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An efficient kinetic resolution of primary propargylic amines with s-factors of up to 56 is reported. The strategy is based on a dual catalytic approach, namely the use of a newly developed and easy-to-make thiourea-amide anion binding catalyst in combination with 4-(dimethylamino)pyridine (DMAP), both employed at a 5 mol % catalyst loading. Benzylic amines are also resolved with s-factors of up to 38.
- Klauber, Eric G.,De, Chandra Kanta,Shah, Tejas K.,Seidel, Daniel
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supporting information; experimental part
p. 13624 - 13626
(2010/11/17)
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- The asymmetric synthesis of (R,R)-formoterol via transfer hydrogenation with polyethylene glycol bound Rh catalyst in PEG2000 and water
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(R,R)-formoterol was synthesized in seven steps with 4-hydroxyl-3-nitro- acetophenone as the starting material. The key intermediate, the chiral secondary alcohol 4, was prepared via Rh-catalyzed asymmetric transfer hydrogenation with (S,S)-PEGBsDPEN as the ligand and sodium formate as the hydrogen donor under mild conditions. With a mixture of PEG 2000 and water as the reaction media, the catalyst system could be recycled four times.
- Huang, Ling,Liu, Juntao,Shan, Wenjun,Liu, Bao,Shi, Anding,Li, Xingshu
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experimental part
p. 206 - 211
(2010/11/18)
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- Syntheses and photochromic studies of dithienylethene-containing imidazolium derivatives and their reactivity towards nucleophiles
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A series of dithienylethene-containing imidazolium salts with various substituents on the 2-position of the imidazolium ring has been synthesized. The photochromic properties of these compounds have been studied, and the closed forms are found to be solva
- Duan, Gongping,Zhu, Nianyong,Yam, Vivian Wing-Wah
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experimental part
p. 13199 - 13209
(2011/02/24)
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- METAL COMPLEXES WITH BORON-NITROGEN HETEROCYCLE CONTAINING LIGANDS FOR USE IN ORGANIC LIGHT EMITTING DEVICES
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Novel organic compounds comprising ligands containing a boron-nitrogen heterocycle are provided. The compounds comprise a ligand L having the structure: Formula I, wherein A and B may represent a 5-membered or 6-membered carbocycle or heterocycle; Xi is selected from the group consisting of carbon and nitrogen; X2 and X3 are independently selected from the group consisting of carbon, nitrogen, and boron; B is a boron-nitrogen heterocycle; R1 and R2 represent mono, di, tri, or tetra substitutions; R1 and R2 are independently selected from the group consisting of hydrogen, alkyl, alkoxy, amino, alkenyl, alkynyl, arylkyl, aryl, and heteroaryl; and the ligand L is coordinated to a metal M having an atomic number greater than 40. In particular, the compound is a metal complex comprising a ligand containing an azaborine. The compounds may be used in organic light emitting devices to provide devices having improved photophysical and electronic properties.
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Page/Page column 54
(2010/12/18)
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- Synthetic analogues of the microtubule-stabilizing sponge alkaloid ceratamine A are more active than the natural product
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Desbromoceratamine A (3) exhibits significantly less potent activity than the natural product ceratamine A (1) in a cell-based assay for antimitotic activity. Synthesis of the ceratamine A analogue 4 has shown that replacing the bromine atoms in the natural product with methyl groups generates an analogue that is more active than natural ceratamine A (1). Further enhancement of the antimitotic activity of the ceratamine pharmacophore has been achieved in the synthetic analogue 33, which has both bromine atoms replaced with methyl groups and an additional methyl substituent on the amino nitrogen at C-2. An efficient synthetic route has been developed to 33 that should enable the first in vivo evaluation of the new ceratamine microtubule-stabilizing pharmacophore and has provided several additional analogues for structure-activity relationship evaluation.
- Nodwell, Matt,Zimmerman, Carla,Roberge, Michel,Andersen, Raymond J.
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experimental part
p. 7843 - 7851
(2011/02/22)
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- Kinetics and mechanisms for the reactions of ozone with unsaturated oxygenated compounds
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Rate coefficients for the reaction of ozone with a series of unsaturated oxygenated compounds are determined in air at atmospheric pressure and (298±3) K. Rate data are obtained using both relative and absolute rate techniques, and the measured rate coefficients are found to be in good agreement. The results show that the reactivity of the compounds with respect to addition of ozone to the double bond is a function of the nature of the oxygenated substituent. Product distribution studies on the reactions provide information on the decomposition pathways for the primary ozonides, and on the effect of the oxygenated group on the relative importance of the degradation pathways. The results are discussed in terms of their importance in the atmospheric oxidation of unsaturated oxygenated compounds.
- Al Mulla, Ismael,Viera, Lisa,Morris, Rebecca,Sidebottom, Howard,Treacy, Jack,Mellouki, Abdelwahid
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experimental part
p. 4069 - 4078
(2011/09/30)
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- The atmospheric oxidation of ethyl formate and ethyl acetate over a range of temperatures and oxygen partial pressures
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The Cl-atom-initiated oxidation of two esters, ethyl formate [HC(O)OCH 2CH3] and ethyl acetate [CH3C(O)OCH 2CH3], has been studied at pressures close to 1 atm as a function of temperature (249-325 K) and O2 partial pressure (50-700 Torr), using an environmental chamber technique. In both cases, Cl-atom attack at the CH2 group is most important, leading in part to the formation of radicals of the type RC(O)OCH(O?)CH3 [R = H, CH3]. The atmospheric fate of these radicals involves competition between reaction with O2 to produce an anhydride compound, RC(O)OC(O)CH3, and the so-called α-ester rearrangement that produces an organic acid, RC(O)OH, and an acetyl radical, CH3C(O). For both species studied, the α-ester rearrangement is found to dominate in air at 1 atm and 298 K. Barriers to the rearrangement of 7.7 ± 1.5 and 8.4 ± 1.5 kcal/mole are estimated for CH3C(O)OCH(O?)CH3 and HC(O)OCH(O?)CH3, respectively, leading to increased occurrence of the O2 reaction at reduced temperature. The data are combined with those obtained from similar studies of other simple esters to provide a correlation between the rate of occurrence of the α-ester rearrangement and the structure of the reacting radical.
- Orlando, John J.,Tyndall, Geoffrey S.
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experimental part
p. 397 - 413
(2011/08/09)
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- Atmospheric chemistry of isopropyl formate and tert-butyl formate
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Formates are produced in the atmosphere as a result of the oxidation of a number of species, notably dialkyl ethers and vinyl ethers. This work describes experiments to define the oxidation mechanisms of isopropyl formate, HC(O)OCH(CH3)2, and tert-butyl formate, HC(O)OC(CH 3)3. Product distributions are reported from both Cl- and OH-initiated oxidation, and reaction mechanisms are proposed to account for the observed products. The proposed mechanisms include examples of the α-ester rearrangement reaction, novel isomerization pathways, and chemically activated intermediates. The atmospheric oxidation of isopropyl formate by OH radicals gives the following products (molar yields): acetic formic anhydride (43%), acetone (43%), and HCOOH (15-20%). The OH radical initiated oxidation of tert-butyl formate gives acetone, formaldehyde, and CO2 as major products. IR absorption cross sections were derived for two acylperoxy nitrates derived from the title compounds. Rate coefficients are derived for the kinetics of the reactions of isopropyl formate with OH (2.4 ± 0.6) × 10-12, and with Cl (1.75 ± 0.35) × 10-11, and for tert-butyl formate with Cl (1.45 ± 0.30) × 10-11 cm3 molecule-1 s-1. Simple group additivity rules fail to explain the observed distribution of sites of H-atom abstraction for simple formates.
- Pimentel, Andre Silva,Tyndall, Geoffrey S.,Orlando, John J.,Hurley, Michale D.,Wallington, Timothy J.,Andersen, Mads P. Sulbaek,Marshall, Paul,Dibble, Theodore S.
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experimental part
p. 479 - 498
(2011/04/12)
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- UREA TYPE CINNAMIDE DERIVATIVE
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Disclosed is a compound represented by the formula (I) below or a pharmacologically acceptable salt thereof. Also disclosed is a use of the compound or salt as a pharmaceutical product. (In the formula, Ar1 represents an imidazolyl group which may be substituted with a C1-6 alkyl group; Ar2 represents a phenyl group which may be substituted with a C1-6 alkoxy group; X1 represents a single bond; R1 and R2 respectively represent a C1-6 alkyl group or the like which may be substituted with a substituent such as a 5- to 14-membered aromatic heterocyclic group; and R3 represents a hydrogen atom or the like.)
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Page/Page column 48
(2009/02/10)
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- Discovery of a sensitive, selective, and tightly binding fluorogenic substrate of bovine plasma amine oxidase
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(Chemical Equation Presented) We report a novel fluorogenic substrate of bovine plasma amine oxidase (BPAO), namely, (2-(6-(aminomethyl)naphthalen-2- yloxy)ethyl)trimethylammonium (ANETA), which displays extremely tight binding to BPAO (Km 183 ± 14 nM) and yet is metabolized fairly quickly (kcat 0.690 ± 0.010 s-1), with the aldehyde turnover product (2-(6-formylnaphthalen-2-yloxy)ethyl)trimefhylammonium serving as a real time reporting fluorophore of the enzyme activity. This allowed for the development of a fluorometric noncoupled assay that is 2 orders of magnitude more sensitive than the spectrophotometric benzylamine assay. The discovery of ANETA involved elaboration of the lead compound 6-methoxy-2-naphthalene- methaneamine by structure-based design, which recognized the ancillary cation binding site of BPAO as the most significant structural features controlling binding affinity. Structure-based design further ensured a high level of selectivity: ANETA is a good substrate of BPAO but is not a substrate of either porcine kidney diamine oxidase (pkDAO) or rat liver monoamine oxidase (MAO-B). ANETA represents the first highly sensitive, selective, and tight binding fluorogenic substrate of a copper amine oxidase that is able to respond directly to the enzyme activity in real time.
- Ling, Ke-Qing,Sayre, Lawrence M.
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experimental part
p. 339 - 350
(2009/04/11)
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- Pyrroloquinoline Derivatives And Their Use As Protein Kinases Inhibitors
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The present invention relates to inhibitors of protein kinases of formula I: which can be used in the treatment of various diseases, notably cancer, inflammation or disorders of the central nervous system. It also relates to pharmaceutical compositions containing the compounds according to the invention and their use in therapy.
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Page/Page column 18
(2009/03/07)
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- NOVEL HETEROCYCLE COMPOUNDS
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The present invention relates to novel compounds which are antagonist or inverse agonists at an opioid receptor. Such compounds are useful in the treatment of obesity and related diseases and/or conditions in mammals, particularly humans. Methods of making and using such compounds are also disclosed.
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Page/Page column 17; 19
(2009/04/24)
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