- A New Chiral Solvating Agent for Carboxylic Acids Based on Directed Hydrogen Bonding
-
Readily available structural modules were combined to a new chiral receptor for carboxylic acids which shows triple hydrogen-bonding to various substrates.Large chemical shift anisochronies were observed with chiral and prochiral carboxylic acids.
- Stork, Thomas,Helmchen, Guenter
-
-
Read Online
- Detoxification of VX and Other V-Type Nerve Agents in Water at 37 °C and pH 7.4 by Substituted Sulfonatocalix[4]arenes
-
Sulfonatocalix[4]arenes with an appended hydroxamic acid residue can detoxify VX and related V-type neurotoxic organophosphonates with half-lives down to 3 min in aqueous buffer at 37 °C and pH 7.4. The detoxification activity is attributed to the millimo
- Schneider, Christian,Bierwisch, Anne,Koller, Marianne,Worek, Franz,Kubik, Stefan
-
-
Read Online
- Carboxyl Methyltransferase Catalysed Formation of Mono- and Dimethyl Esters under Aqueous Conditions: Application in Cascade Biocatalysis
-
Carboxyl methyltransferase (CMT) enzymes catalyse the biomethylation of carboxylic acids under aqueous conditions and have potential for use in synthetic enzyme cascades. Herein we report that the enzyme FtpM from Aspergillus fumigatus can methylate a broad range of aromatic mono- and dicarboxylic acids in good to excellent conversions. The enzyme shows high regioselectivity on its natural substrate fumaryl-l-tyrosine, trans, trans-muconic acid and a number of the dicarboxylic acids tested. Dicarboxylic acids are generally better substrates than monocarboxylic acids, although some substituents are able to compensate for the absence of a second acid group. For dicarboxylic acids, the second methylation shows strong pH dependency with an optimum at pH 5.5–6. Potential for application in industrial biotechnology was demonstrated in a cascade for the production of a bioplastics precursor (FDME) from bioderived 5-hydroxymethylfurfural (HMF).
- Ashbrook, Chloe,Carnell, Andrew J.,Goulding, Ellie,Hatton, Harry,Johnson, James R.,Kershaw, Neil M.,McCue, Hannah V.,Rigden, Daniel J.,Ward, Lucy C.
-
supporting information
(2022/02/21)
-
- Substitution Effect on 2-(Oxazolinyl)-phenols and 1,2,5-Chalcogenadiazole -Annulated Derivatives: Emission-Color-Tunable, Minimalistic Excited-State Intramolecular Proton Transfer (ESIPT)-Based Luminophores
-
Minimalistic 2-(oxazolinyl)-phenols substituted with different electron-donating and -withdrawing groups as well as 1,2,5-chalcogenadiazole-annulated derivatives thereof were synthesized and investigated in regard to their emission behavior in solution as well as in the solid state. Depending on the nature of the incorporated substituent and its position, emission efficiencies were increased or diminished, resulting in AIE or ACQ characteristics. Single-crystal analysis revealed J- and H-type packing motifs and a so-far undescribed isolation of ESIPT-based fluorophores in the keto form.
- G?bel, Dominik,Rusch, Pascal,Duvinage, Daniel,Stauch, Tim,Bigall, Nadja-C.,Nachtsheim, Boris J.
-
supporting information
p. 14333 - 14355
(2021/10/20)
-
- Cobalt-Catalyzed Deprotection of Allyl Carboxylic Esters Induced by Hydrogen Atom Transfer
-
A brief, efficient method has been developed for the removal of the allyl protecting group from allyl carboxylic esters using a Co(II)/TBHP/(Me2SiH)2O catalytic system. This facile strategy displays excellent chemoselectivity, functional group tolerance, and high yields. This transformation probably occurs through the hydrogen atom transfer process, and a Co(III)-six-membered cyclic intermediate is recommended.
- Li, Nan,Gui, Yizhen,Chu, Mengqi,You, Mengdi,Qiu, Xiaohan,Liu, Hejia,Wang, Shiang,Deng, Meng,Ji, Baoming
-
supporting information
p. 8460 - 8464
(2021/11/13)
-
- Silica-Mediated Monohydrolysis of Dicarboxylic Esters
-
A new method for the monohydrolysis of dicarboxylic esters is presented, involving as key step a silanolysis at elevated temperatures at the silica gel surface. In the second step, the surface bound silyl esters are cleaved off under mild conditions, giving a straightforward and fast access to half esters. Based on recovered starting material generally yields well above 70 % are achieved, both, with stiff aromatic as well as flexible aliphatic substrates, as long as the ester groups involved are remote enough from each other. Otherwise competing reactions are becoming determinative, anhydride formation in the case of phthalates and decarbonylative fragmentation in the case of malonates. The new method was also successfully tested on a multigram scale with a minimalistic apparatus setup.
- Dyker, Gerald
-
supporting information
p. 6773 - 6776
(2021/12/31)
-
- A Br?nsted acidic, ionic liquid containing, heteropolyacid functionalized polysiloxane network as a highly selective catalyst for the esterification of dicarboxylic acids
-
A Br?nsted acidic, ionic liquid containing, heteropolyanion functionalized polysiloxane network was formed by self-condensation of dodecatungstophosphoric acid and a zwitterionic organosilane precursor containing both imidazolinium and sulfonate groups. The resulting hybrid material POS-HPA-IL was investigated as a catalyst for the selective esterification of dicarboxylic acids.
- Rajabi, Fatemeh,Wilhelm, Christian,Thiel, Werner R.
-
supporting information
p. 4438 - 4444
(2020/08/10)
-
- Ni-Catalyzed Carboxylation of C(sp2)-S Bonds with CO2: Evidence for the Multifaceted Role of Zn
-
Nickel-catalyzed reductive carboxylation reactions of aryl electrophiles typically require the use of metallic reducing agents. At present, the prevailing perception is that these serve as both a source of electrons and as a source of Lewis acids that may aid CO2 insertion into the Ni-C bond. Herein, we provide evidence for the in situ formation of organometallic species from the metallic reductant, a step that has either been ruled out or has been unexplored in catalytic carboxylation reactions with metal powder reductants. Specifically, we demonstrate that Zn(0) acts as a reductant and that Zn(II) generates arylzinc species that might play a role in the C(sp2)-S carboxylation of arylsulfonium salts. Overall, the reductive Ni-catalyzed C(sp2)-S carboxylation reaction proceeds under mild conditions in a non-amide solvent, displays a wide substrate scope, and can be applied to the formal para C-H carboxylation of arenes.
- Yanagi, Tomoyuki,Somerville, Rosie J.,Nogi, Keisuke,Martin, Ruben,Yorimitsu, Hideki
-
p. 2117 - 2123
(2020/02/28)
-
- Cobalt-catalyzed carboxylation of aryl and vinyl chlorides with CO2
-
The transition-metal-catalyzed carboxylation of aryl and vinyl chlorides with CO2 is rarely studied, and has been achieved only with a Ni catalyst or combination of palladium and photoredox. In this work, the cobalt-catalyzed carboxylation of aryl and vinyl chlorides and bromides with CO2 has been developed. These transformations proceed under mild conditions and exhibit a broad substrate scope, affording the corresponding carboxylic acids in good to high yields.
- Wang, Yanwei,Jiang, Xiaomei,Wang, Baiquan
-
supporting information
p. 14416 - 14419
(2020/12/01)
-
- Cobalt-Catalyzed Reductive Carboxylation of Aryl Bromides with Carbon Dioxide
-
Cobalt-catalyzed reductive carboxylation of aryl bromides with carbon dioxide has been developed. The reaction proceeded under one atm pressure of CO2 at 40 °C in the presence of cobalt iodide/2,2′-bipyridine catalysts and zinc dust as a reducing reagent. Various aryl bromides could be converted to the corresponding carboxylic acids in good to high yields. Preliminary mechanistic experiments ruled out intervention of intermediate organozinc species for carboxylation with CO2, thus suggesting a direct CO2 insertion into the corresponding ArCoBr species. (Figure presented.).
- Hang, Wei,Yi, Yaping,Xi, Chanjuan
-
supporting information
p. 2337 - 2341
(2020/04/30)
-
- Bisubstrate inhibitors of nicotinamide N-methyltransferase (NNMT) with enhanced activity
-
Nicotinamide N-methyltransferase (NNMT) catalyzes the methylation of nicotinamide to form N-methylnicotinamide. Overexpression of NNMT is associated with a variety of diseases, including a number of cancers and metabolic disorders, suggesting a role for NNMT as a potential therapeutic target. By structural modification of a lead NNMT inhibitor previously developed in our group, we prepared a diverse library of inhibitors to probe the different regions of the enzyme's active site. This investigation revealed that incorporation of a naphthalene moiety, intended to bind the hydrophobic nicotinamide binding pocket via π-πstacking interactions, significantly increases the activity of bisubstrate-like NNMT inhibitors (half-maximal inhibitory concentration 1.41 μM). These findings are further supported by isothermal titration calorimetry binding assays as well as modeling studies. The most active NNMT inhibitor identified in the present study demonstrated a dose-dependent inhibitory effect on the cell proliferation of the HSC-2 human oral cancer cell line.
- Gao, Yongzhi,Van Haren, Matthijs J.,Moret, Ed E.,Rood, Johannes J. M.,Sartini, Davide,Salvucci, Alessia,Emanuelli, Monica,Craveur, Pierrick,Babault, Nicolas,Jin, Jian,Martin, Nathaniel I.
-
p. 6597 - 6614
(2019/08/20)
-
- Peptidomimetic plasmepsin inhibitors with potent anti-malarial activity and selectivity against cathepsin D
-
Following up the open initiative of anti-malarial drug discovery, a GlaxoSmithKline (GSK) phenotypic screening hit was developed to generate hydroxyethylamine based plasmepsin (Plm) inhibitors exhibiting growth inhibition of the malaria parasite Plasmodium falciparum at nanomolar concentrations. Lead optimization studies were performed with the aim of improving Plm inhibition selectivity versus the related human aspartic protease cathepsin D (Cat D). Optimization studies were performed using Plm IV as a readily accessible model protein, the inhibition of which correlates with anti-malarial activity. Guided by sequence alignment of Plms and Cat D, selectivity-inducing structural motifs were modified in the S3 and S4 sub-pocket occupying substituents of the hydroxyethylamine inhibitors. This resulted in potent anti-malarials with an up to 50-fold Plm IV/Cat D selectivity factor. More detailed investigation of the mechanism of action of the selected compounds revealed that they inhibit maturation of the P. falciparum subtilisin-like protease SUB1, and also inhibit parasite egress from erythrocytes. Our results indicate that the anti-malarial activity of the compounds is linked to inhibition of the SUB1 maturase plasmepsin subtype Plm X.
- Zogota, Rimants,Kinena, Linda,Withers-Martinez, Chrislaine,Blackman, Michael J.,Bobrovs, Raitis,Pantelejevs, Teodors,Kanepe-Lapsa, Iveta,Ozola, Vita,Jaudzems, Kristaps,Suna, Edgars,Jirgensons, Aigars
-
supporting information
p. 344 - 352
(2018/12/11)
-
- Tandem one-pot CO2 reduction by PMHS and silyloxycarbonylation of aryl/vinyl halides to access carboxylic acids
-
The present study discloses the synthesis of aryl/vinyl carboxylic acids from Csp2-bound halides (Cl, Br, I) in a carbonylative path by using silyl formate (from CO2 and hydrosilane) as an instant CO-surrogate. Hydrosilane provides hydride for reduction and its oxidation product silanol serves as a coupling partner. Mono-, di-, and tri-carboxylic acids were obtained from the corresponding aryl/vinyl halides.
- Paridala, Kumaraswamy,Lu, Sheng-Mei,Wang, Meng-Meng,Li, Can
-
supporting information
p. 11574 - 11577
(2018/10/31)
-
- Carboxylation of Aromatic and Aliphatic Bromides and Triflates with CO2 by Dual Visible-Light–Nickel Catalysis
-
We report the efficient carboxylation of bromides and triflates with K2CO3 as the source of CO2 in the presence of an organic photocatalyst in combination with a nickel complex under visible light irradiation at room temperature. The reaction is compatible with a variety of functional groups and has been successfully applied to the synthesis and derivatization of biologically active molecules. In particular, the carboxylation of unactivated cyclic alkyl bromides proceeded well with our protocol, thus extending the scope of this transformation. Spectroscopic and spectroelectrochemical investigations indicated the generation of a Ni0 species as a catalytic reactive intermediate.
- Meng, Qing-Yuan,Wang, Shun,K?nig, Burkhard
-
supporting information
p. 13426 - 13430
(2017/10/07)
-
- SO2F2-Mediated One-Pot Synthesis of Aryl Carboxylic Acids and Esters from Phenols through a Pd-Catalyzed Insertion of Carbon Monoxide
-
A one-pot Pd-catalyzed carbonylation of phenols into their corresponding aryl carboxylic acids and esters through the insertion of carbon monoxide has been developed. This procedure offers a direct synthesis of aryl carboxylic acids and esters from inexpensive and abundant starting materials (phenols, SO2F2 and CO) under mild conditions. This method tolerates a broad range of functional groups and is also applicable for the modification of complicated natural products.
- Fang, Wan-Yin,Leng, Jing,Qin, Hua-Li
-
supporting information
p. 2323 - 2331
(2017/09/06)
-
- Visible-Light-Driven Carboxylation of Aryl Halides by the Combined Use of Palladium and Photoredox Catalysts
-
A highly useful, visible-light-driven carboxylation of aryl bromides and chlorides with CO2 was realized using a combination of Pd(OAc)2 as a carboxylation catalyst and Ir(ppy)2(dtbpy)(PF6) as a photoredox catalyst. This carboxylation reaction proceeded in high yields under 1 atm of CO2 with a variety of functionalized aryl bromides and chlorides without the necessity of using stoichiometric metallic reductants.
- Shimomaki, Katsuya,Murata, Kei,Martin, Ruben,Iwasawa, Nobuharu
-
supporting information
p. 9467 - 9470
(2017/07/24)
-
- Oxalic acid as the: In situ carbon monoxide generator in palladium-catalyzed hydroxycarbonylation of arylhalides
-
An efficient palladium-catalyzed hydroxycarbonylation reaction of arylhalides using oxalic acid as a CO source has been developed. The reaction features high safety, low catalyst loading, and a broad substrate scope, and provides a safe and tractable approach to access a variety of aromatic carboxylic acid compounds. Mechanistic studies revealed the decomposition pattern of oxalic acid.
- Shao, Changdong,Lu, Ailan,Wang, Xiaoling,Zhou, Bo,Guan, Xiaohong,Zhang, Yanghui
-
supporting information
p. 5033 - 5040
(2017/07/10)
-
- Room Temperature Carbonylation of (Hetero) Aryl Pentafluorobenzenesulfonates and Triflates using Palladium-Cobalt Bimetallic Catalyst: Dual Role of Cobalt Carbonyl
-
An efficient method for the carbonylation of (hetero) aryl pentafluorobenzenesulfonates and triflates under exceptionally mild conditions using palladium/dicobalt octacarbonyl [Pd/Co2(CO)8] has been developed. Besides acting as carbon monoxide (CO) source, Co2(CO)8enhances the reaction rate by accelerating the CO insertion through an in situ generated bimetallic palladium cobalt tetracarbonyl [Pd-Co(CO)4] complex. Under the optimized reaction condition, carbonylation of a wide range of activated and deactivated, as well as sterically hindered and heteroaromatic, substrates proceeded efficiently at room temperature. The high chemoselectivity and improved synthesis of biologically relevant Isoguvacine and Lazabemide intermediates highlights its scope as a valuable synthetic method. The generality of this protocol was further extended to other electrophiles (bromides, chlorides and tosylates). (Figure presented.).
- Joseph, Jayan T.,Sajith, Ayyiliath M.,Ningegowda, Revanna C.,Shashikanth, Sheena
-
p. 419 - 425
(2017/02/10)
-
- One-pot synthetic method for m-acetylbenzoic acid
-
The invention relates to a synthetic method, in particular to a one-pot synthetic method for m-acetylbenzoic acid. According to the one-pot synthetic method for the m-acetylbenzoic acid, there is no need to purify an intermediate product. The reaction equation of the m-acetylbenzoic acid is shown in the description, wherein R refers to methyl or ethyl, and R1 refers to methyl or ethyl or n-propyl. Compared with synthetic methods in the prior art, the synthetic method has the advantages that raw materials are low in price and easy to get, reaction conditions are mild, the obtained intermediate product can be directly used for a reaction in a next step without being separated and purified, and therefore process cost is greatly lowered.
- -
-
-
- Electrophilicity and nucleophilicity of commonly used aldehydes
-
The present approach for determining the electrophilicity (E) and nucleophilicity (N) of aldehydes includes a kinetic study of KMNO4 oxidation and NaBH4 reduction of aldehydes. A transition state analysis of the KMNO4 promoted aldehyde oxidation reaction has been performed, which shows a very good correlation with experimental results. The validity of the experimental method has been tested using the experimental activation parameters of the two reactions. The utility of the present approach is further demonstrated by the theoretical versus experimental relationship, which provides easy access to E and N values for various aldehydes and offers an at-a-glance assessment of the chemical reactivity of aldehydes in various reactions. the Partner Organisations 2014.
- Pratihar, Sanjay
-
p. 5781 - 5788
(2014/07/22)
-
- Nickel-catalysed carboxylation of organoboronates
-
A nickel/N-heterocyclic carbene (NHC) catalysed carboxylation of aryl-, heteroaryl- and alkenylboronates, affording the corresponding carboxylic acids, has been developed. This transformation proceeds under one atmosphere of CO 2 with a broad range of substrates and exhibits good functional group compatibility. the Partner Organisations 2014.
- Makida, Yusuke,Marelli, Enrico,Slawin, Alexandra M. Z.,Nolan, Steven P.
-
supporting information
p. 8010 - 8013
(2014/07/08)
-
- Glycosylation of 'basic' alcohols: Methyl 6-(hydroxymethyl)picolinate as a case study
-
Glycosylation is promoted by acid promoters rendering the reactions with basic acceptors challenging. This report presents an in depth study involving methyl 6-(hydroxymethyl)picolinate as the model acceptor and 22 glycosyl donors to afford the desired glycosides in good yields ranging from 46% to 85%. Several parameters were evaluated, including the protecting groups of the glycosyl donor, the leaving group at the anomeric center, and the promoter. The influence of the pyridine ring was evident with a benzene-based acceptor affording high yields of glycoside (79%) in comparison to the pyridine-based acceptor (46%). The present work provides a general and reliable access to pyridine-containing glycosides.
- Wang, Shuai,Lafont, Dominique,Rahkila, Jani,Picod, Benjamin,Leino, Reko,Vidal, Sébastien
-
supporting information
p. 35 - 46
(2013/05/21)
-
- Aromatics from pyrones: Esters of terephthalic acid and isophthalic acid from methyl coumalate
-
The Diels-Alder reaction of methyl coumalate with alkenes bearing electron-withdrawing groups provides terephthalates or isophthalates in good yields, with the regioselectivity depending on the electron-withdrawing group. The reaction of methyl coumalate with the salt of acrylic acid gave only the monoester of isophthalic acid. Density functional theory (B3LYP/6-31 + G(d,p)) computations of the energies of the competing transition states of the para-selective Diels-Alder reactions are in good agreement with experiment. The surprising regioselectivity of methyl coumalate with activated alkenes is attributed to a secondary orbital interaction between the pyrone oxygen and the dienophile LUMO, which switches the regiochemistry expected from simple frontier molecular orbital theory arguments. The Royal Society of Chemistry 2013.
- Kraus, George A.,Pollock III, Gerald R.,Beck, Christie L.,Palmer, Kyle,Winter, Arthur H.
-
p. 12721 - 12725
(2013/08/23)
-
- Birch Reductive Alkylation of Methyl m-(Hydroxymethyl)benzoate Derivatives and the Behavior of o- and p-(Hydroxymethyl)benzoates under Reductive Alkylation Conditions
-
Birch reductive alkylation of methyl m-(hydroxymethyl)benzoate derivatives, using lithium in ammonia-tetrahydrofuran in the presence of tertbutyl alcohol, can be achieved without significant loss of benzylic oxygen substituents. Similar treatment of o- and p-(hydroxymethyl)benzoate derivatives results largely in loss of benzylic oxygen substituents. The results are rationalized by computations describing electron density patterns in the putative radical anion intermediate involved in these reactions.
- Fretz, Samuel J.,Hadad, Christopher M.,Hart, David J.,Vyas, Shubham,Yang, Dexi
-
supporting information
p. 83 - 92
(2013/03/29)
-
- METHOD OF REGIOSELECTIVE SYNTHESIS OF SUBSTITUTED BENZOATES
-
A method of synthesis of para-substituted benzoate esters and acids is provided, wherein the para-substituted regioisomer is obtained substantially free of the meta-substituted impurity, the method comprising contacting a coumalate ester or acid and an un activated alkene at elevated temperature in the presence of a metal oxidation catalyst and an oxidant. The metal oxidation catalyst can be palladium, such as palladium on carbon, and the oxidant can be the oxygen gas in ambient air. The reaction can be carlied out without solvent or in high boiling hydrocarbon solvents such as mesitylene. When the un activated alkene is a monosubstituted alkene, yields of at least about 50 or 60% of para-substituted ester and acid products, respectively, are obtained, substantially free of the regioisomelic meta-substituted impurity.
- -
-
Page/Page column 20; 21
(2013/03/26)
-
- Kinetics and mechanism of the oxidation of substituted benzaldehydes with bis(pyridine)silver permanganate
-
The oxidation of thirty-six ortho-, meta- and para-substituted benzaldehydes by bis(pyridine)silver permanganate (BPSP) resulted in the formation of the corresponding benzoic acids. The reaction is first order with respect to both BPSP and aldehydes. The reaction is catalyzed by hydrogen ions. The rate of reaction increases with an increase in the amount of acetic acid in the solvent. The correlation analyses of the rate of oxidation of thirty-six aldehydes were performed in terms of Charton's LDR and LDRS equations. The rate of oxidation of meta- and para-substituted benzaldehydes showed excellent correlation with Charton's LDR equation. The rates of ortho-compounds showed excellent correlation with LDRS equation. The oxidation para-compounds is more susceptible to the delocalization effect. The oxidation of ortho- and meta-compounds exhibited a greater dependence on the field effect. The polar reaction constants are negative indicating an electron-deficient centre in the rate-determining step. A mechanism involving a nucleophilic attack on the carbonyl group by a permanganate-oxygen and a subsequent hydride transfer has been proposed.
- Purohit, Trupti,Banerji, Jayshree,Kotai, Laszlo,Sajo,Banerji,Sharma, Pradeep K.
-
p. 1045 - 1052
(2013/01/14)
-
- 3-Mercapto-1,2,4-triazoles and N-acylated thiosemicarbazides as metallo-β-lactamase inhibitors
-
The production of β-lactamases is an effective strategy by which pathogenic bacteria can develop resistance against β-lactam antibiotics. While inhibitors of serine-β-lactamases are widely used in combination therapy with β-lactam antibiotics, there are no clinically available inhibitors of metallo-β-lactamases (MBLs), and so there is a need for the development of such inhibitors. This work describes the optimisation of a lead inhibitor previously identified by fragment screening of a compound library. We also report that thiosemicarbazide intermediates in the syntheses of these compounds are also moderately potent inhibitors of the IMP-1 MBL from Pseudomonas aeruginosa. The interactions of these inhibitors with the active site of IMP-1 were examined using in silico methods.
- Faridoon,Hussein, Waleed M.,Vella, Peter,Islam, Nazar Ul,Ollis, David L.,Schenk, Gerhard,McGeary, Ross P.
-
supporting information; experimental part
p. 380 - 386
(2012/02/04)
-
- Synthesis and luminescent properties of Tb(III) complex with a novel pyrazolone ligand and its interaction with bovine serum albumin
-
A novel aromatic pyrazolone ligand, methyl 6-(3-methyl-1-phenyl-5- pyrazolone-4-carbonyl) pyridine-2-carboxylic acid (L), and its corresponding Tb(III) complexes, Tb(L)3·2H2O, was successfully prepared. L and its complex were charact
- Yang, Zhengfa,Tang, Ruiren,Zhang, Zhenfeng
-
-
- Structure-Reactivity correlation in the oxidation of substituted benzaldehydes by tetraethylammonium chlorochromate
-
Oxidation of 36 monosubstituted benzaldehydes by tetraethylammonium chlorochromate in dimethyl sulphoxide, leads to the formation of corresponding benzoic acids. The reaction is of first order with respect to chlorochromate and aldehydes. The reaction is promoted by H+; the H+ dependence has the form kobs = a + b[H+]. The oxidation of duteriated benzaldehyde exhibits substantial primary kinetic isotope effect. The reaction was studied in 19 different organic solvents and the effect of solvent was analyzed using Taft's and Swain's multiparametric equations. The rates of the oxidation of para- and meta-substituted benzaldehydes showed excellent correlation in terms of Charton's triparametric LDR equation, whereas the oxidation of ortho-substituted benzaldehydes were correlated well with tetraperametric LDRS equation. The oxidation of para-substituted benzaldehydes is more susceptible to the delocalized effect than is the oxidation of ortho- and meta- substituted compounds, which display a greater dependence on the field effect. The positive value of h suggests the presence of an electron-deficient reaction centre in the rate-determining step. The reaction is subjected to steric acceleration by the orthosubstituents. A suitable mechanism has been proposed.
- Gehlot,Prasadrao,Sharma
-
experimental part
p. 1173 - 1178
(2012/01/05)
-
- Process for the carboxylation of aryl halides with palladium catalysts
-
A process for the carboxylation of an aryl halide to yield an aryl carboxylic acid, in which the aryl halide and CO2 are contacted in an organic solvent under inert atmosphere and in the presence of a reducing agent and an adequate catalyst system.
- -
-
Page/Page column 9
(2011/05/04)
-
- NOVEL FXR (NR1H4 ) BINDING AND ACTIVITY MODULATING COMPOUNDS
-
The present invention relates to compounds which bind to the NR1 H4 receptor (FXR) and act as agonists of the NR1 H4 receptor (FXR). The invention further relates to the use of the compounds for the preparation of a medicament for the treatment of diseases and/or conditions through binding of said nuclear receptor by said compounds, and to a process for the synthesis of said compounds.
- -
-
Page/Page column 45; 46
(2011/04/13)
-
- Novel FXR (NR1H4) binding and activity modulating compounds
-
The present invention relates to compounds which bind to the NR1H4 receptor (FXR) and act as agonists of the NR1H4 receptor (FXR). The invention further relates to the use of the compounds for the preparation of a medicament for the treatment of diseases and/or conditions through binding of said nuclear receptor by said compounds, and to a process for the synthesis of said compounds.
- -
-
Page/Page column 18
(2011/04/14)
-
- Design and synthesis of potent and selective BACE-1 inhibitor
-
Highly potent BACE-1 protease inhibitors have been developed from an inhibitors containing a hydroxyethylene (HE) core displaying aryloxymethyl or benzyloxymethyl P1 side chain and a methoxy P1′ side chain. The target molecules were synthesized in good overall yields from chiral carbohydrate starting materials. The inhibitors show high BACE-1 potency and good, selectivity against cathepsin D, where the most potent inhibitor furnishes BACE-1 Ki ? 1 nM and displays > 1000-fold selectivity over cathepsin D.
- Bj?rklund, Catarina,Oscarson, Stefan,Benkestock, Kurt,Borkakoti, Neera,Jansson, Katarina,Lindberg, Jimmy,Vrang, Lotta,Hallberg, Anders,Rosenquist, Asa,Samuelsson, Bertil
-
supporting information; experimental part
p. 1458 - 1464
(2010/08/03)
-
- Correlation analysis of reactivity in the oxidation of substituted benzaldehydes by morpholinium chlorochromate
-
Oxidation of thirty six monosubstituted benzaldehydes by morpholinium chlorochromate (MCC) in dimethylsulphoxide (DMSO), leads to the formation of corresponding benzoic acids. The reaction is of first order with respect to MCC. A Michaelis-Menten type kinetics is observed with respect to benzaldehydes. The reaction is promoted by hydrogen ions; the hydrogen-ion dependence has the form kobs = a + b [H+]. The oxidation of [2H] benzaidehyde (PhCDO) exhibited a substantial primary kinetic isotope effect. The reaction was studied in nineteen organic solvents and the effect of solvent was analysed using Taft's and Swain's multi-parametric equations. The rates of the oxidation of para- and meta-substituted benzaldehydes showed excellent correlation in terms of Charton's triparametric LDR equation, whereas the oxidation of ortho-substituted benzaldehydes were correlated well with tetraparametric LDRS equation. The oxidation of para-substituted benzaldehydes is more susceptible to the delocalized effect than is the oxidation of ortho- and meta-substituted compounds, which display a greater dependence on the field effect. The positive value of η suggests the presence of an electron-deficient reaction centre in the rate-determining step. The reaction is subjected to steric acceleration by the ortho-substituents. A suitable mechanism has been proposed.
- Choudhary, Anurag,Malani,Agarwal,Sharma,Sharma, Vinita
-
experimental part
p. 927 - 935
(2010/07/16)
-
- Design, synthesis, and biological activity of isophthalic acid derivatives targeted to the C1 domain of protein kinase C
-
Protein kinase C (PKC) is a widely studied molecular target for the treatment of cancer and other diseases. We have approached the issue of modifying PKC function by targeting the C1 domain in the regulatory region of the enzyme. Using the X-ray crystal structure of the PKC δ C1b domain, we have discovered conveniently synthesizable derivatives of dialkyl 5-(hydroxymethyl)isophthalate that can act as potential C1 domain ligands. Structure-activity studies confirmed that the important functional groups predicted by modeling were indispensable for binding to the C1 domain and that the modifications of these groups diminished binding. The most promising compounds were able to displace radiolabeled phorbol ester ([3H]PDBu) from PKC α and δ at Ki values in the range of 200-900 nM. Furthermore, the active isophthalate derivatives could modify PKC activation in living cells either by inducing PKC-dependent ERK phosphorylation or by inhibiting phorbol-induced ERK phosphorylation. In conclusion, we report here, for the first time, that derivatives of isophthalic acid represent an attractive novel group of C1 domain ligands that can be used as research tools or further modified for potential drug development.
- Af Genn?s, Gustav Boije,Talman, Virpi,Aitio, Olli,Ekokoski, Elina,Finel, Moshe,Tuominen, Raimo K.,Yli-Kauhaluoma, Jari
-
supporting information; experimental part
p. 3969 - 3981
(2010/01/16)
-
- Palladium-catalyzed direct carboxylation of aryl bromides with carbon dioxide
-
(Chemical Equation Presented) A novel protocol for the direct carbon dioxide insertion (CO2) into aryl halides in a catalytic manner is presented herein. Unlike other carboxylation methods using CO2, there is no need for the synthesis of the corresponding organometallic intermediates. Additionally, and in contrast to the well-established carbonylation processes, our protocol does not use highly toxic CO for the preparation of benzoic acids. Furthermore, this method is distinguished by its mild conditions, allowing the tolerance of a wide range of functional groups and substitution patterns. The crucial step of the process involves a challenging catalytic CO2 insertion into Pd-C bonds. Copyright
- Correa, Arkaitz,Martin, Ruben
-
supporting information; experimental part
p. 15974 - 15975
(2010/02/15)
-
- Structure-reactivity correlation in the oxidation of substituted benzaldehydes by 2,2-bipyridinium chlorochromate
-
Oxidation of thirty six monosubstituted benzaldchydes by 2,2′-bipyridiniuin chlorochromate (BPCC) in diniethylsulphoxide (DMSO), leads to the formation of corresponding benzoic acids. The reaction is of first order with respect to both BPCC and aldehydes. The reaction is promoted by hydrogen ions; the hydrogen ion dependence has the form kobs= a + b[H+]. The oxidation of [2H]benzaldehyde (PhCDO) exhibited a substantial primary kinetic isotope effect. The reaction was studied in nineteen different organic solvents and the effect of solvent was analysed using Taft's and Swain's multi-parametric equations. The rates of the oxidation of para- and mete-substituted benzaldehydes showed excellent correlation in terms of Charton's triparametric LDR equation, whereas the oxidation of orfAo-substituted benzaldehydes were correlated well with tetraparametric LDRS equation. The oxidation of para-substituted benzaldehydes is more susceptible to the delocalized effect than is the oxidation of ortho- and mem-substituted compounds, which display a greater dependence on the field effect. The positive value of η suggests the presence of an electron-deficient reaction centre in the rate-determining step. The reaction is subjected to steric acceleration by the ortho-substituents. A suitable mechanism has been proposed.
- Sharma, Pradeep K.
-
experimental part
p. 1281 - 1288
(2009/12/31)
-
- Kinetics and mechanism of the oxidation of substituted benzaldehydes by tetrabutylammonium tribromide
-
The oxidation of thirty-six monosubstituted benzaldehydes by tetrabutylammonium tribromide (TBATB), in aqueous acetic acid solution, leads to the formation of the corresponding benzoic acids. The reaction is first order with respect to both TBATB and aldehydes. The reaction failed to induce the polymerization of acrylonitrile. There is no effect of tetrabutylammonium chloride ions on the reaction rate. The oxidation of [2H]benzaldehyde (PhCDO) indicated the presence of a substantial kinetic isotope effect. The effect of solvent composition indicated that the reaction rate increases with an increase in the polarity of the medium. The rates of oxidation of meta- and para-substituted benzaldehydes showed excellent correlations in terms of Charton's triparametric LDR equation whereas the oxidation of ortho-substituted benzaldehydes correlated well with tetraparametric LDS equation. The oxidation of para-substituted benzaldehydes is more susceptible to the delocalization effect but the oxidation of ortho- and meta-substituted compounds displayed a greater dependence on the field effect. The positive value of η suggests the presence of an electron-deficient reaction center in the rate-determining step. The reaction is subjected to steric acceleration when ortho-substituents are present.
- Chouhan,Sharma, Monica,Sharma, Vinita
-
p. 582 - 587
(2008/09/21)
-
- Aspartic protease inhibitors via C1-homologation of peptidic aldehydes and studies on reduced amide isosteres
-
(R)-Configured isophthalic hydroxyethylamines play an important role in the inhibition of β-secretase (BACE1). We present the synthesis of a number of (S)-configured hydroxyethylamine derivatives via 2-iodoethanol intermediates and the comparison with the
- Braun, Hannes A.,Zall, Andrea,Brockhaus, Manfred,Schütz, Marco,Meusinger, Reinhard,Schmidt, Boris
-
p. 7990 - 7993
(2008/03/14)
-
- Norstatines from Aldehydes by sequential organocatalytic α-amination and passerini reaction
-
The combination of the enantioselective, organocatalytic α-amination of aldehydes by diazodicarboxylates and the Passerini reaction provides rapid access to norstatine-based peptidomimetics. These intermediates were elaborated further by deprotection and cleavage of the N-N bond to provide useful building blocks for aspartic protease inhibitors. Coupling of the compounds 76-86 with the mono-isophthalamide 91 provided moderate inhibitors of human β-secretase (BACE) 92-102. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
- Umbreen, Sumaira,Brockhaus, Manfred,Ehrenberg, Helmut,Schmidt, Boris
-
p. 4585 - 4595
(2007/10/03)
-
- Novel scaffolds for beta-helix mimicry
-
Functionalized pyridazine derivatives having a low molecular weight and pharmaceutical compositions thereof are useful as alpha-helix mimetics and for treating conditions and/or disorders mediated by alpha-helix-binding receptors and proteins.
- -
-
Page/Page column 19-20
(2008/06/13)
-
- Rhodium(I)-catalyzed carboxylation of aryl- and alkenylboronic esters with CO2
-
When the esters of arylboronic acids with 2,2-dimethylpropan-1,3-diol were treated with a catalytic amount of [Rh(OH)(cod)]2 in the presence of 1,3-bis(diphenylphosphino)propane and CsF in dioxane at 60 °C under carbon dioxide atmosphere, the benzoic acid derivatives were obtained in good yields. Reactions of alkenylboronic esters also proceeded under similar conditions to give α,β-unsaturated carboxylic acids. As these boronic esters are now easily available through coupling or direct borylation reactions, this method would be a useful method for the preparation of various functionalized aryl- and alkenyl-carboxylic acids. Copyright
- Ukai, Kazutoshi,Aoki, Masao,Takaya, Jun,Iwasawa, Nobuharu
-
p. 8706 - 8707
(2007/10/03)
-
- Carboxylation and esterification of functionalized arylcopper reagents
-
Functionalized arylcopper reagents have been produced in good yields at 25 °C from activated copper and the corresponding functionalized aryl iodides without the need of traditional organolithium or Grignard precursors. These organocopper compounds will undergo carboxylation with CO2 to form the corresponding copper benzoates. In turn, these salts can be acidified to produce the functionalized aryl acids or treated with appropriate alkyl halides in the presence of a dipolar aprotic solvent to generate the corresponding aryl esters. This methodology permits the formation of functionalized organic acids and esters that could not be generated by the carboxylation of organomagnesium compounds.
- Ebert, Greg W.,Juda, Wayne L.,Kosakowski, Robert H.,Ma, Bing,Dong, Liming,Cummings, Keith E.,Phelps, Mwita V. B.,Mostafa, Adel E.,Luo, Jianyuan
-
p. 4314 - 4317
(2007/10/03)
-
- Laser Flash Photolysis of tert-Butyl Aroylperbenzoates: Kinetics of the Singlet and Triplet States and the Aroylphenyl Radicals
-
tert-Butyl aroylperbenzoates (1-4) were studied by laser flash photolysis (LFP). LFP (380 nm, pulse width ~350 fs) of 2 and 3 allowed direct observation of their singlet states, which showed broad absorption (λmax ~ 625 nm; τ ~ 20 and ~7.9 ps, respectively). The triplet state of each (λmax ~ 530-560 nm) rapidly dissociates by O-O cleavage as indicated by the short triplet lifetimes (e.g., triplet lifetime of 3 ~0.74 ns). The ~550 nm absorption obtained from the 355 nm LFP (pulse width ~7 ns) of 1, 2, and 4 has been assigned to the corresponding aroylphenyl radicals. Two representative radicals (4-benzoylphenyl 5 and 3-(4′-methylbenzoyl)phenyl 6) investigated in detail showed solvent-dependent lifetimes. Absolute bimolecular rate constants of reactions of these radicals with various quenchers including double-bond-containing monomers have been observed to range from 7.56 × 107 to 1.68 × 109 M-1 s-1 in CCl4 at room temperature. A possible structure of the aroylphenyl radicals and the transition responsible for the 550 nm absorption are discussed.
- Shah, Bipin K.,Neckers, Douglas C.
-
p. 1830 - 1835
(2007/10/03)
-
- Aspartyl protease inhibitors
-
The present invention provides compounds having the formula: wherein R1, R′, R2, R3, R3′, R4, X1, X2 and X3 are as defined herein, and pharmaceutical compositions thereof. The present invention also provides methods of inhibiting proteases, more specifically aspartyl proteases. In certain embodiments, compounds inhibit BACE (β-site APP-cleaving enzyme), and thus are useful in the treatment or prevention of a disease characterized by β-amyloid deposits in the brain (including, but not limited to, Alzheimer's Disease). The present invention also provides methods for preparing compounds of the invention.
- -
-
-
- HETERO BIARYL DERIVATIVES AS MATRIX METALLOPROTEINASE INHIBITORS
-
This invention provides compounds defined by Formula I or a pharmaceutically acceptable salt thereof, wherein Rl, Q, S, T, U, V, and R2 are as defined in the specification. The invention also provides pharmaceutical compositions comprising a compound of Formula I, or a pharmaceutically acceptable salt thereof, as defined in the specification, together with a' pharmaceutically acceptable carrier, diluent, or excipient. The invention also provides methods of inhibiting an MMP-13 enzyme in an animal, comprising administering to the animal a compound of Formula I, or a pharmaceutically acceptable salt thereof. The invention also provides methods of treating a disease mediated by an MMP-13 enzyme in a patient, comprising administering to the patient a' compound of Formula I, or a pharmaceutically acceptable salt thereof, either alone or in a pharmaceutical composition. The invention also provides methods of treating diseases such as heart disease, multiple sclerosis, osteo- and rheumatoid arthritis, arthritis other than osteo- or rheumatoid arthritis, cardiac insufficiency,,inflammatory bowel, disease, heart failure, age-related macular degeneration, chronic obstructive pulmonary disease, asthma, periodontal diseases, psoriasis, atherosclerosis, and osteoporosis in a patient, comprising administering to the patient a compound of Formula I, or a pharmaceutically, acceptable salt thereof, either alone or in a pharmaceutical composition. The invention also provides combinations, comprising a compound of Formula I, or a pharmaceutically acceptable salt thereof, together with another pharmaceutically active, component as described in the specification.
- -
-
Page/Page column 107-108
(2008/06/13)
-
- Correlation analysis of reactivity in the oxidation of substituted benzaldehydes by benzyltrimethylammonium tribromide
-
The oxidation of benzaldehyde and thirty-five monosubstituted benzaldehydes by benzyltrimethylammonium tribromide (BTMAB) in aqueous acetic acid leads to the formation of the corresponding benzoic acids, The reaction is first order with respect to each the benzaldehyde and BTMAB. The reaction failed to induce the polymerization of acrylonitrile. There is no effect of benzyltrimethylammonium chloride on the reaction rate. The oxidation of [2H]benzaldehyde (PhCDO) indicated the presence of a substantial kinetic isotope effect. The effect of solvent composition indicated that the reaction rate increases with an increase in the polarity of the solvent. The rates of oxidation of meta- and para-substituted benzaldehydes are correlated in terms of Charton's triparametric LDR equation whereas the oxidation of ortho-substituted benzaldehydes are correlated with tetraparametric LDRS equation. The oxidation of para- substituted benzaldehydes is more susceptible to the delocalization effect than is the oxidation of ortho-and meta-substituted compounds, which display a greater dependence on the field effect. The positive value of η suggests the presence of an electron-deficient reaction centre in the rate-determining step. The reaction is subjected to steric hindrance by the ortho-substituents.
- Mehla, Satish K.,Kothari, Seema,Banerji, Kalyan K.
-
p. 832 - 838
(2007/10/03)
-
- Refinement and evaluation of a pharmacophore model for flavone derivatives binding to the benzodiazepine site of the GABAA receptor
-
To further develop and evaluate a pharmacophore model previously proposed by Cook and co-workers (Drug Des. Discovery 1995, 12, 193-248) for ligands binding to the benzodiazepine site of the GABAA receptor, 40 new flavone derivatives have been synthesized and their affinities for the benzodiazepine site have been determined. Two new regions of steric repulsive interactions between ligand and receptor have been characterized, and the receptor region in the vicinity of 6- and 3′-substituents has been mapped out. 2′-Hydroxy substitution is shown to give a significant increase in affinity, which is interpreted in terms of a novel hydrogen bond interaction with the previously proposed hydrogen bond-accepting site A2. On the basis of the results of these studies and the refined pharmacophore model, 5′-bromo-2′-hydroxy-6-methylflavone, the highest affinity flavone derivative reported so far (Ki = 0.9 nM), was successfully designed. A comparison of the pharmacophore model with a recently proposed alternative model (Marder; et al. Bioorg. Med. Chem., 2001, 9, 323-335) has been made.
- Kahnberg, Pia,Lager, Erik,Rosenberg, Celia,Schougaard, Jette,Camet, Linda,Sterner, Olov,Nielsen, Elsebet ?stergaard,Nielsen, Mogens,Liljefors, Tommy
-
p. 4188 - 4201
(2007/10/03)
-
- Correlation analysis of reactivity in the oxidation of substituted benzaldehydes by pyridinium hydrobromide perbromide
-
The oxidation of benzaldehyde and 35 monosubstituted benzaldehydes by pyridinium hydrobromide perbromide (PHPB) in aqueous acetic acid leads to the formation of the corresponding benzoic acids. The reaction is first order with respect to each of the benzaldehydes and PHPB. Addition of pyridinium bromide has no effect on the rate of oxidation. The oxidation of [2H]benzaldehyde (PhCDO) indicated the presence of a substantial kinetic isotope effect. The effect of solvent composition indicated that the reaction rate increases with increase in the polarity of the solvent. The rates of oxidation of meta- and para-substituted benzaldehydes were correlated in terms of Charton's triparametric LDR equation whereas those of ortho-substituted benzaldehydes were correlated with a tetraparametric LDRS equation. The oxidations of para- and ortho-substituted benzaldehydes are more susceptible to the delocalization effect while the oxidation of meta-substituted compounds displays a greater dependence on the fi eld effect. The positive value of η suggests the presence of an electron-deficient reaction centre in the rate-determining step. The reaction is subjected to steric hindrance by the ortho substituents.
- Aneja, Meenakshi,Kothari, Seema,Banerji, Kalyan K.
-
p. 650 - 656
(2007/10/03)
-
- Kinetics and mechanism of the oxidation of substituted benzaldehydes by hexamethylenetetramine-bromine
-
The oxidation of thirty-six monosubstituted benzaldehydes by hexa-methylenetetramine-bromine (HABR), in aqueous acetic acid solution, leads to the formation of the corresponding benzoic acids. The reaction is first order with respect to HABR. Michaelis-Menten-type kinetics were observed with respect to aldehyde. The reaction failed to induce the polymerization of acrylonitrile. There is no effect of hexamethylenetetramine on the reaction rate. The oxidation of [2H]benzaldehyde (PhCDO) indicated the presence of a substantial kinetic isotope effect. The effect of solvent composition indicated that the reaction rate increases with an increase in the polarity of the solvent. The rates of oxidation of meta- and para-substituted benzaldehydes showed excellent correlations in terms of Charton's triparametric LDR equation, whereas the oxidation of ortho-substituted benzaldehydes correlated well with tetraparametric LDRS equation. The oxidation of para-substituted benzaldehydes is more susceptible to the delocalization effect but the oxidation of ortho- and meta-substituted compounds displayed a greater dependence on the field effect. The positive value of γ suggests the presence of an electron-deficient reaction center in the rate-determining step. The reaction is subjected to steric acceleration when ortho-substituents are present.
- Gangwani,Sharma,Banerji
-
p. 615 - 622
(2007/10/03)
-
- Kinetics and mechanism of the oxidation of substituted benzaldehydes by benzyltrimethylammonium chlorobromate
-
The oxidation of 35 monosubstituted benzaldehydes by benzyltrimethylammonium chlorobromate (BTMACB) in aqueous acetic acid leads to the formation of the corresponding benzoic acids. The reaction is first order with respect to both benzaldehyde and BTMACB. The reaction failed to induce the polymerization of acrylonitrile. There is no effect of benzyltrimethylammonium chloride or potassium bromide on the reaction rate. The oxidation of [2H]benzaldehyde (PhCDO) indicated the presence of a substantial kinetic isotope effect. The effect of solvent composition indicated that the reaction rate increases with an increase in the polarity of the solvent. The rates of oxidation of meta- and para-substituted benzaldehydes were correlated in terms of Charton's triparametric LDR equation, whereas the oxidation of ortho-substituted benzaldehydes was correlated with the tetraparametric LDRS equation. The oxidation of para- substituted benzaldehydes is more susceptible to the delocalization effect, whereas the oxidation of ortho-and meta-substituted compounds displayed a greater dependence on the field effect. The positive value of η suggests the presence of an electron-deficient reaction center in the rate-determining step. The reaction is subjected to steric hindrance by the ortho substituents.
- Raju, V. Sitarama,Sharma, Pradeep K.,Banerji, Kalyan K.
-
p. 3322 - 3325
(2007/10/03)
-