cas 25804-49-3, tert-butyl 4-hydroxybenzoate

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Silver/manganese dioxide nanorod catalyzed hydrogen-borrowing reactions and tert-butyl ester synthesis
Silver/manganese dioxide (Ag@MnO2) nanorods are synthesized and characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray powder diffraction, and X-ray photoelectron spectroscopy. It was discovered that Ag@MnO2 nanorods can realize hydrogen-borrowing reactions in high yields and are also effective for the synthesis of tert-butyl esters from aryl cyanides and tert-butyl hydroperoxide in a short period of time. Mechanistic experiments revealed that this catalytic system acts as a Lewis acid in hydrogen-borrowing reactions, while the synthesis of tert-butyl esters occurs through a radical pathway. This is the first report on the excellent catalytic activity of Ag@MnO2 nanorods as a catalyst.
Luo, Huanhuan,Wang, Dawei,Xu, Zhaojun,Yang, Bobin,Yang, Yike
p. 708 - 715
(2021/03/03)

Novel nicotinoid structures for covalent modification of wood: An environmentally friendly way for its protection against insects
Timber is constantly exposed to environmental influences under outdoor conditions which limits its lifetime and usability. In order to counteract the damaging processes caused by insects, we have developed a novel and more environmentally friendly method to protect wood materials via covalent modification by organic insecticides. Starting with an important class of synthetic insecticides which are derived from the natural insecticide nicotine, various new carboxylic acid derivatives of imidacloprid were made accessible. These activated neonicotinoids were utilized for the chemical modification of wood hydroxy groups. In contrast to conventional wood preservation methods in which biocides are only physically bound to the surface for a limited time, the covalent fixation of the preservative guarantees a permanent effect against wood pests, demonstrated in standardized biological tests. Additionally, the environmental interaction caused by non-bound neonicotinoids is significantly reduced, since both, a smaller application rate is required and leaching of the active ingredient is prevented. By minimizing the pest infestation, the lifetime of the material increases while preserving the natural appearance of the material.
Acker, Sophie,Kaufmann, Dieter E.,Namyslo, Jan C.,Plarre, Rudy,S?ftje, Martin
p. 15726 - 15733
(2020/05/13)

Dual aminoquinolate diarylboron and nickel catalysed metallaphotoredox platform for carbon-oxygen bond construction
Herein, aminoquinolate diarylboron complexes are utilized as photocatalysts in dual Ni/photoredox catalyzed carbon-oxygen construction reactions. Via this unified metallaphotoredox platform, diverse (hetero)aryl halides can be conveniently coupled with acids, alcohols and water. This method features operational simplicity, broad substrate scope and good compatibility with functional groups. This journal is
Day, Craig,Jia, Xin,Wei, Lanfeng,Xu, Liang,Zu, Weisai
supporting information
p. 8273 - 8276
(2020/08/17)

A Zirconium Indazole Carboxylate Coordination Polymer as an Efficient Catalyst for Dehydrogenation-Cyclization and Oxidative Coupling Reactions
Rational ligand design is crucial for achieving widespread applications of coordination polymers. The preparation, structural characterisation, and catalytic applications of zirconium (IV) coordination polymer (Zr-IDA), which was derived from 1-(carboxymethyl)-1H-indazole-5-carboxylic acid are reported. The Zr-IDA catalyst contains porous and highly crystalline particles with a quasi-spherical morphology around 100 nm in size, and Zr was coordinated with both O and N as shown by FT-IR and XPS measurements. Importantly, the Zr-IDA catalyst shows great activity, selectivity and stability in the oxidative coupling of benzyl cyanides with tert-butyl hydroperoxide to afford tert-butyl peresters, and the dehydrogenation cyclization of o-phenylenediamines with aromatic alcohols to afford 1,2-disubstituted benzimidazole derivatives. Mechanistic investigations were carried out to study these reactions and the developed catalytic system in more detail.
Sang, Xinxin,Hu, Xinyu,Tao, Rong,Zhang, Yilin,Zhu, Haiyan,Wang, Dawei
p. 123 - 129
(2020/02/21)

Pore size dependent cation adsorption in a nanoporous polymer film derived from a plastic columnar phase
Self-supporting polymer thin films were obtained by the polymerization of an AB3-type hydrogen-bonded complex in the plastic columnar phase. Porous polymers with pore diameters of ≈1.1 and ≈1.6 nm lined with either -COOH or -COONa groups were fabricated from the polymer thin films. Both the pore size and pore collapse influence the adsorption of cations.
Bhattacharjee, Subham,Lugger, Jody A. M.,Sijbesma, Rint P.
supporting information
p. 9521 - 9524
(2018/08/28)

Synthesis and Reactivity of 18F-Labeled α,α-Difluoro-α-(aryloxy)acetic Acids
In this work, we describe the 18F-labeling of α,α-difluoro-α-(aryloxy)acetic acid derivatives and demonstrate that these building blocks are amenable to post-18F-fluorination functionalization. Protodecarboxylation offers a new entry to 18F-difluoromethoxyarene, and the value of this approach is further demonstrated with coupling processes leading to representative 18F-labeled TRPV1 inhibitors and TRPV1 antagonists.
Khotavivattana, Tanatorn,Calderwood, Samuel,Verhoog, Stefan,Pfeifer, Lukas,Preshlock, Sean,Vasdev, Neil,Collier, Thomas L.,Gouverneur, Véronique
supporting information
p. 568 - 571
(2017/02/10)

Preparation method for high-purity propofol
The invention provides a preparation method for high-purity propofol. The preparation method includes the following steps that S1, under the strong base catalysis condition, a compound shown in the general formula (1) is heated and conducts the decarboxylic reaction in solvent, and a solution system containing the propofol is obtained after acid regulation; and S2, after extraction and alkali washing are conducted on the solution system containing the propofol, the high-purity propofol is obtained through reduced pressure distillation. The invention belongs to the technical field of medicine. The preparation method is wide in raw material source, low in cost, gentle in reaction condition, few in product impurity type and high in product quality, purity is higher than 99.0%, and the requirements for raw material medicine can be met.
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(2017/05/02)

Compound has the negative light dispersion, negative dispersion of this compound-containing composition and containing the composition for preparing anisotropic optical (by machine translation)
The invention relates to a kind of reverse wdxrf compound, containing the compound reverse of wavelength dispersion composition and containing the optical anisotropic body. According to the present invention the reverse of wavelength dispersion composition is capable of providing a stronger and more stable reverse wdxrf nature, and can offer excellent optical performance of the optical anisotropic body. (by machine translation)
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Paragraph 0223; 0224

(2016/10/09)

COMPOUNDS HAVING NEGATIVE OPTICAL DISPERSION, NEGATIVE OPTICAL DISPERSION COMPOSITION COMPRISING THE COMPOUNDS, AND OPTICALLY ANISOTROPIC BODY COMPRISING THE COMPOSITION (As Amended)
The present invention relates to a reverse wavelength dispersion compound, a reverse wavelength dispersion composition including the same, and an optically anisotropic body including the same. The reverse wavelength dispersion composition according to the present invention can provide a stronger and more stable reverse wavelength dispersion property, and makes it possible to provide an optically anisotropic body having excellent optical properties.
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Paragraph 0154

(2016/08/17)

COMPOSITION FOR MANUFACTURING OPTICAL ELEMENTS WITH NEGATIVE OPTICAL DISPERSION AND OPTICALLY ANISOTROPIC BODY MANUFACTURED THEREFROM
The present invention relates to a composition for manufacturing optical elements with negative optical dispersion, and an optically anisotropic body prepared therefrom. According to the present invention, the optically anisotropic body showing stable reverse wavelength dispersion can be prepared more simply by using the composition for optical elements, and it is possible to apply the same to liquid crystal display devices as an optical film such as a thin-layer broadband λ/4 plate.
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(2017/04/26)

An efficient method for the preparation of: Tert -butyl esters from benzyl cyanide and tert -butyl hydroperoxide under the metal free condition
A novel protocol to synthesize tert-butyl esters from benzyl cyanides and tert-butyl hydroperoxide has been successfully achieved. In the presence of tert-butyl hydroperoxide, Csp3-H bond oxidation, C-CN bond cleavage and C-O bond formation proceeded smoothly in one pot under the metal-free condition.
Chen, Xiuling,Li, Yan,Wu, Minghu,Guo, Haibing,Jiang, Longqiang,Wang, Jian,Sun, Shaofa
p. 102023 - 102027
(2016/11/09)

Discovery and optimization of adamantane carboxylic acid derivatives as potent diacylglycerol acyltransferase 1 inhibitors for the potential treatment of obesity and diabetes
Abstract We have developed a series of adamantane carboxylic acid derivatives exhibiting potent diacylglycerol acyltransferase 1 (DGAT1) inhibitory activities. Optimization of the series led to the discovery of E-adamantane carboxylic acid compound 43c, which showed excellent in vitro activity with an IC50 value of 5 nM against human and mouse DGAT1, also good druggability as well as microsomal stability and safety profiles such as hERG, CYP and cytotoxicity. Compound 43c significantly reduced plasma triglyceride levels in vivo (in rodents and zebrafish) and also showed bodyweight gain reduction and glucose area under curve (AUC) lowering efficacy in diet-induced obesity (DIO) mice.
Pagire, Suvarna H.,Pagire, Haushabhau S.,Lee, Gwi Bin,Han, Seo-Jung,Kwak, Hyun Jung,Kim, Ji Young,Kim, Ki Young,Rhee, Sang Dal,Ryu, Jeong Im,Song, Jin Sook,Bae, Myung Ae,Park, Mi-Jin,Kim, Dooseop,Lee, Duck Hyung,Ahn, Jin Hee
p. 716 - 735
(2015/08/04)

Aryloxymaleimides for cysteine modification, disulfide bridging and the dual functionalization of disulfide bonds
Tuning the properties of maleimide reagents holds significant promise in expanding the toolbox of available methods for bioconjugation. Herein we describe aryloxymaleimides which represent 'next generation maleimides' of attenuated reactivity, and demonstrate their ability to enable new methods for protein modification at disulfide bonds.
Marculescu, Cristina,Kossen, Hanno,Morgan, Rachel E.,Mayer, Patrick,Fletcher, Sally A.,Tolner, Berend,Chester, Kerry A.,Jones, Lyn H.,Baker, James R.
supporting information
p. 7139 - 7142
(2014/07/07)

Oxadiazole-isopropylamides as potent and noncovalent proteasome inhibitors
Screening of the 50 000 ChemBridge compound library led to the identification of the oxadiazole-isopropylamide 1 (PI-1833) which inhibited chymotrypsin-like (CT-L) activity (IC50 = 0.60 μM) with little effects on the other two major proteasome proteolytic activities, trypsin-like (T-L) and postglutamyl-peptide-hydrolysis-like (PGPH-L). LC-MS/MS and dialysis show that 1 is a noncovalent and rapidly reversible CT-L inhibitor. Focused library synthesis provided 11ad (PI-1840) with CT-L activity (IC50 = 27 nM). Detailed SAR studies indicate that the amide moiety and the two phenyl rings are sensitive toward modifications. Hydrophobic residues, such as propyl or butyl in the para position (not ortho or meta) of the A-ring and a m-pyridyl group as B-ring, significantly improve activity. Compound 11ad (IC50 = 0.37 μM) is more potent than 1 (IC50 = 3.5 μM) at inhibiting CT-L activity in intact MDA-MB-468 human breast cancer cells and inhibiting their survival. The activity of 11ad warrants further preclinical investigation of this class as noncovalent proteasome inhibitors.
Ozcan, Sevil,Kazi, Aslamuzzaman,Marsilio, Frank,Fang, Bin,Guida, Wayne C.,Koomen, John,Lawrence, Harshani R.,Sebti, Sa?d M.
supporting information
p. 3783 - 3805
(2013/06/27)

[5,6]HETEROCYCLIC COMPOUND
Abstract: An object of the present invention is to provide a novel low molecular weight compound exhibiting an osteogenesis-promoting action. This object is achieved by a compound having the general formula (I) or a pharmacologically acceptable salt thereof. In the general formula (I), R1 and R2 represent hydrogen atoms, and the like; R3 represents a hydrogen atom, and the like; X, Y, and Z represent nitrogen atoms, and the like; A represents a phenylene group, and the like; n represents 1 or 2, and the like; and V and W represent oxygen atoms, and the like.
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(2013/03/26)

PROTEASOME CHYMOTRYPSIN-LIKE INHIBITION USING PI-1833 ANALOGS
Focused library synthesis and medicinal chemistry on an oxadiazole- isopropylamide core proteasome inhibitor provided the lead compound that strongly inhibits CT-L activity. Structure activity relationship studies indicate the amide moiety and two phenyl rings are sensitive toward synthetic modifications. Only para-substitution in the A-ring was important to maintain potent CT-L inhibitory activity. Hydrophobic residues in the A-ring?s para-position and meta-pyridyl group at the B- ring significantly improved inhibition. The meta-pyridyl moiety improved cell permeability. The length of the aliphatic chain at the para position of the A-ring is critical with propyl yielding the most potent inhibitor, whereas shorter (i.e. ethyl, methyl or hydrogen) or longer (i.e. butyl, propyl and hexyl) chains demonstrating progressively less potency. Introduction of a stereogenic center next to the ether moiety (i.e. substitution of one of the hydrogens by methyl) demonstrated chiral discrimination in proteasome CT-L activity inhibition (the S-enantiomer was 35-40 fold more potent than the R-enantiomer)
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(2012/10/08)

Synthesis of novel dithienothiophene- and 2,7-carbazole-based conjugated polymers and H-bonded effects on electrochromic and photovoltaic properties
Three kinds of dithienothiophene/carbazole-based conjugated polymers (P1-P3), which bear acid-protected and benzoic acid pendants in P2 and P3, respectively, were synthesized via Suzuki coupling reaction. Interestingly, P1-P3 exhibited reversible electrochromism during the oxidation processes of cyclic voltammogram studies, and P3 (with H-bonds) revealed the best electrochromic property with the most noticeable color change. According to powder X-ray diffraction (XRD) analysis, these polymers exhibited obvious diffraction features indicating bilayered packings between polymer backbones and π-π stacking between layers in the solid state. Compared with the XRD data of P2 (without H-bands), H-bonds of P3 induced a higher crystallinity in the small-angle region (corresponding to a higher ordered bilayered packings between polymer backbones), but with a similar crystallinity in the wide angle region indicating a comparable π-π stacking distance between layers. Moreover, based on the preliminary photovoltaic properties of PSC devices (P1-P3 blended individually with PCBM acceptor in the weight ratio of 1:1), P3 (with H-bonds) possessed the highest power conversion efficiency of 0.61% (with J sc = 2.26 mA/cm2, FF = 29.8%, and Voc = 0.9 V). In contrast to P2 (without H-bands), the thermal stability, crystallinity, and electrochromic along with photovoltaic properties of P3 were generally enhanced due to its H-bonded effects.
Fang, Hsiao-Ping,Lin, Jia-Wei,Chiang, I-Hung,Chu, Chih-Wei,Wei, Kung-Hwa,Lin, Hong-Cheu
p. 5011 - 5022
(2013/01/15)

CYCLIC COMPOUND HAVING SUBSTITUTED PHENYL GROUP
An object of the present invention is to provide a novel low molecular weight compound exhibiting an osteogenesis-promoting action. This object is achieved by a compound having the general formula (I) or a pharmacologically acceptable salt thereof: wherein each substituent is defined as follows: R1 represents an alkyl group or the like; R2 represents an alkyl group or the like; R3 represents a hydrogen atom or the like; and Z represents -CH= or -N=.
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(2012/03/08)

Catalytic asymmetric synthesis of a tertiary benzylic carbon center via phenol-directed alkene hydrogenation
An expeditious synthetic approach to chiral phenol 1, a key building block in the preparation of a series of drug candidates, is reported. The strategy includes a cost-effective and readily scalable route to cyclopentanone 3 from isobutyronitrile (10). The sterically hindered and enolizable ketone 3 was subsequently employed in a challenging Grignard addition mediated by LaCl 3?2LiCl. A novel preparation of the lanthanide reagent required for this transformation is described. To complete the process, a highly enantioselective hydrogenation step afforded the target (1). The importance of the phenol group to the success of this asymmetric transformation is discussed.
Caille, Seb,Crockett, Rich,Ranganathan, Krishnakumar,Wang, Xiang,Woo, Jacqueline C. S.,Walker, Shawn D.
p. 5198 - 5206
(2011/08/09)

Designing dendrimers for ocular drug delivery
New series of phosphorus-containing dendrimers, having one quaternary ammonium salt as core and carboxylic acid terminal groups have been synthesized from generation 0 (3 carboxylic acid terminal groups) to generation 2 (12 carboxylic acid terminal groups). These dendrimers react with the neutral form of carteolol (an ocular anti-hypertensive drug used to treat glaucoma) to afford ion pair (saline) species. The solubility in water of these charged dendrimers depends on the generation considered: generation 0 (3 carteolol) is well soluble, whereas generation 1 (6 carteolol) and generation 2 (12 carteolol) are poorly soluble. These dendrimers have been tested in vivo, as vehicle for ocular drug delivery of carteolol to rabbits.
Spataro, Gregory,Malecaze, Francois,Turrin, Cedric-Olivier,Soler, Vincent,Duhayon, Carine,Elena, Pierre-Paul,Majoral, Jean-Pierre,Caminade, Anne-Marie
experimental part
p. 326 - 334
(2010/04/04)

Palladium-catalyzed amination of aryl and heteroaryl tosylates at room temperature
Mild palladium-catalyzed aminations of aryl tosylates and the first aminations of heteroaryl tosylates are described. In the presence of the combination of L2Pd(0) (L = P(o-tol)3) and the hindered Josiphos ligand CyPF-t-Bu, a variety of primary alkylamines and arylamines react with both aryl and heteroaryl tosylates at room temperature to form the corresponding secondary arylamines in high yields with complete selectivity for the monoarylamine. These reactions at room temperature occur in many cases with catalyst loadings of 0.1 mol % and 0.01 mol % in one case, constituting the most efficient aminations of aryl tosylates by nearly 2 orders of magnitude. This catalyst is made practical by the development of a convenient method to synthesize the L2Pd(0) precursor. This complex is stable to air as a solid. In contrast to conventional relative rates for reactions of aryl sulfonates, the reactions of aryl tosylates are faster than parallel reactions of aryl triflates, and the reactions of aryl tosylates are faster than parallel or competitive reactions of aryl chlorides. Copyright
Ogata, Tokutaro,Hartwig, John F.
supporting information; experimental part
p. 13848 - 13849
(2009/02/07)

Generation and suppression of 3-/4-functionalized benzynes using zinc ate base (TMP-Zn-ate): New approaches to multisubstituted benzenes
We present full details of our new methods for preparing functionalized benzynes with lithium di-alkyl(2,2,6,6-tetramethylpiperidino)zincate (R 2Zn(TMP)Li) through deprotonative zincation as a key reaction. In this system, by choosing appropriate ligands for the zincate, either regioselective zincation of functionalized haloaromatics or the generation of substituted benzynes can be controlled in good yields with excellent chemoselectivity, using the same substrate. Zincation with tBu 2Zn(TMP)Li followed by electrophilic trapping or zincation with Me2Zn(TMP)Li followed by nucleophilic or diene trapping is shown to be a powerful tool for the chemoselective preparation of 1,2,3-/1,2,4- trisubstituted benzene derivatives. These methods offer far greater generality than previous methods for the synthesis of multifunctionalized benzenes. Computational/theoretical studies of the reaction mechanism of this unique benzyne formation indicated that preferential coordination of the dialkylzinc moiety of zincate to halogen is the reason for the reduced activation energy of the elimination, that is, for the formation of the benzyne. The role of the ligands on Zn in accelerating/decelerating the elimination is also discussed.
Uchiyama, Masanobu,Kobayashi, Yuri,Furuyama, Taniyuki,Nakamura, Shinji,Kajihara, Yumiko,Miyoshi, Tomoko,Sakamoto, Takao,Kondo, Yoshinori,Morokuma, Keiji
p. 472 - 480
(2008/10/09)

Fabrication of a nanoparticle gradient substrate by thermochemical manipulation of an ester functionalized SAM
The hydrolysis of methyl ester (-CO2Me) and tert-butyl ester (-CO2tBu) functionalized SAMs as a function of subphase temperature and pH is described. Contact angle measurements show that the methyl ester functionalized monolayer does not hydrolyse in pH 1-13 aqueous solutions heated up to 80 °C. In contrast, the -CO2tBu functionalized monolayer hydrolysed below pH 5. The rate and the extent of the hydrolysis were dependent on the temperature and pH of the aqueous solution. Using the Cassie equation, the activation energy for the hydrolysis of CO 2tBu-phenyl functionalized SAM was determined as 75 ± 7 kJ mol-1 from the contact angle measurements. Furthermore, the adhesion properties of -CO2tBu and -COOH functionalized SAMs were investigated by depositing -NR2 and -COOH functionalized polystyrene nanoparticles onto the surfaces at pH 3 and 9. By AFM, it was observed that the particles bind preferentially to the -COOH functionalized SAM and the adhesion was pH dependent, with the largest coverage being observed at pH 3. Using the acquired understanding of the hydrolysis of -CO2tBu functionalized SAM and the particle adhesion properties, a simple and facile approach towards fabricating a particle density gradient on this surface is demonstrated. An acid gradient SAM (20 mm long) was prepared by mounting one end of a -CO2tBu functionalized SAM onto the hot side of a Peltier element (80 °C) in pH 1 aqueous solution. The substrate was subsequently immersed into a colloidal solution of -NR 2 functionalized polystyrene nanoparticles, removed and rinsed. By AFM, the particle density was shown to be dependent on the surface coverage of -COOH moieties of the underlying SAM. The density started at 104 particles μm-2 on the hydrolysed end down to 0 particles μm-2 on the non-hydrolysed end. The Royal Society of Chemistry.
Iqbal, Parvez,Critchley, Kevin,Bowen, James,Attwood, David,Tunnicliffe, David,Evans, Stephen D.,Preece, Jon A.
experimental part
p. 5097 - 5110
(2009/10/02)

INSULIN DERIVATIVE
The present invention relates to novel human insulin derivatives which are soluble at physiological pH values and have a prolonged profile of action. The invention also relates to methods of providing such derivatives, to pharmaceutical compositions containing them, to methods of treating diabetes and hyperglycaemia using the insulin derivatives of the invention and to the use of such insulin derivatives in the treatment of diabetes and hyperglycaemia.
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(2008/06/13)

4-amino-thieno[3,2-c] pyridine-7-carboxylic acid derivatives
The present invention relates to compounds of the formula medicaments containing them and the use of these compounds as pharmaceutically active agents. The compounds exhibit activity as Raf kinase inhibitors and therefore may be useful for the treatment of diseases mediated by said kinases, especially as anticancer agents.
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(2010/11/26)

Synthesis and evaluation of substrate-mimicking cytosolic phospholipase A2 inhibitors - Reducing the lipophilicity of the arachidonyl chain isostere
The high lipophilicity of a series of cytosolic phospholipase A2 inhibitors has been reduced by the modification of a decyloxyphenyl chain designed to mimic the arachidonyl group of the natural substrate. These changes have resulted in an improvement in the whole cell potency of the inhibitors.
Walters, Iain,Bennion, Colin,Connolly, Stephen,Croshaw, Pamela J.,Hardy, Kim,Hartopp, Paul,Jackson, Clive G.,King, Sarah J.,Lawrence, Louise,Mete, Antonio,Murray, David,Robinson, David H.,Stein, Linda,Wells, Edward,Withnall, W. John
p. 3645 - 3649
(2007/10/03)

SUBSTITUTED HETEROCYCLES FOR THE TREATMENT OF ABNORMAL CELL GROWTH
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(2008/06/13)

Silica Chloride: A Versatile Heterogeneous Catalyst for Esterification and Transesterification
Silica chloride has been found to be an efficient catalyst for esterification of carboxylic acids (aliphatic, aromatic and conjugated) with alcohols (primary, secondary and tertiary) as well as for transesterification of esters (by both alcoholysis and acidolysis).
Srinivas,Mahender,Das, Biswanath
p. 2479 - 2482
(2007/10/03)

Lewis Acids as Highly Efficient Catalysts for the Decarboxylative Esterification of Carboxylic Acids with Dialkyl Dicarbonates
Mild Lewis acids such as Mg(ClO4)2 show a new level of catalytic activity for the decarboxylative esterification of carboxylic acids with commercially available dialkyl dicarbonates. In the presence of as little as one mol % Mg(ClO4)2 catalyst, carboxylic acids can thus easily and near quantitatively be protected at room temperature, e.g., as methyl, benzyl, or t-butyl esters. Only volatile by-products are released so that the purification of the products is particularly easy. Many sensitive functionalities are tolerated, including even phenol esters, or free hydroxy and BOC groups.
Goossen,Doehring
p. 943 - 947
(2007/10/03)

Indolylpiperidine derivatives as antihistaminic and antiallergic agents
Indolylpiperidine compounds of formula (I) wherein: A1 represents an alkylene, alkyleneoxy, alkylenethio, alkanoyl or hydroxyalkylene group; A2 represents a single bond, an alkylene or alkenylene group; W represents a single bond or a phenylene or furanylene group which is unsubstituted or substituted by one or more halogen atoms, alkoxy groups and/or alkyl groups; R1 represents a hydrogen atom or an alkyl, alkenyl, alkynyl, alkoxyalkyl, alkenyloxyalkyl, alkynyloxyalkyl alkoxy-alkoxyalkyl, phenylalkyl group wherein the phenyl ring is unsubstituted or substituted by one or more halogen atoms or alkyl, alkoxy or arylalkoxy groups, or a cycloalkylalkyl group wherein the cycloalkyl group is unsubstituted or substituted by one or more halogen atoms, alkyl groups or alkoxy groups; R2 represents a hydrogen or halogen atom or an alkyl or alkoxy group; and R3 represents a carboxyl group or a tetrazolyl group; and pharmaceutically acceptable salts thereof, process for their preparation and medicinal use.
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(2008/06/13)

Mechanism of Site-Directed Protein Cross-Linking. Protein-Directed Selectivity in Reactions of Hemoglobin with Aryl Trimesates
Site-directed cross-linking of hemoglobin has become an efficient way to produce a structurally defined altered protein with desirable functional properties. The reagent trimesoyl tris(3,5-dibromosalicylate) (1) introduces a bis amide cross-link derived from the ∈-amino groups of the side chains of the two β-Lys-82 residues in human hemoglobin. The basis of its specificity was investigated using a set of analogues of 1 (2-12). There are marked differences in the reaction patterns of these compounds with amino groups in hemoglobin compared to reactions with n-propylamine. The compounds that effectively modify the protein contain a carboxyl group ortho to the phenolic oxygen of the ester, while materials with meta or para carboxyl groups give little or no reaction. In contrast, the reactions with n-propylamine are slowest with the ortho carboxyl materials. Addition of the unreactive compound 5 to a solution containing hemoglobin reduces the ability of 1 to modify the protein, showing that the unreactive compound binds but does not react. On the basis of these observations and the known reaction patterns of salicylates, it is clear that the environment in the protein controls the reaction, regardless of the inherent reactivity of the reagent. We propose that the carboxyl group positions the reagent critically within the protein. Only the ortho arrangement permits transfer of the acyl function to the nucleophile.
Kluger, Ronald,de Stefano, Vittorio
p. 214 - 219
(2007/10/03)

Langmuir films of amphiphilic crown ethers
We have used X-ray reflectivity and grazing-incidence X-ray diffraction to study amphiphilic crown ethers 1 and 2 at the air-water interface. A new synthetic route was employed, which substantially reduced the level of impurities. Unlike previous studies of 1, we saw no evidence of a first-order lying-down to standing-up transition of the alkyl tails. We did observe in both compounds a gradual reorientation of the tails away from the interface as the film was compressed, followed by an irreversible collapse to a multilayer structure. The monolayer films have a fluid-like inplane structure, while the multilayer films are crystalline. ? 1999 American Chemical Society.
Heiney, Paul A.,Stetzer, MacKenzie R.,Mindyuk, Oksana Y.,DiMasi, Elaine,McGhie, Andrew R.,Liu, Hu,Smith III, Amos B.
p. 6206 - 6214
(2007/10/03)

Retinoid-like compounds
The present invention relates to a compound of formula I STR1 or a nontoxic pharmaceutically acceptable salt, physiologically hydrolyzable ester or solvate thereof, in whichX is --O--CO--, --NH--CO--, --CS--NH--, --CO--O--, --CO--NH--, --COS--, --SCO--, --SCH 2 --, --CH 2 --CH 2 --, --C C--, --CH 2 --NH--, --COCH 2 --, --NHCS--, --CH 2 S--, --CH 2 O--, --OCH 2 --, --NHCH 2 -- or --CR 5 CR 6 --;R m and R k are independently hydrogen, halogen, C 1-6 alkyl, hydroxy, C 1-6 alkyloxy or nitro;n is zero or one;R 4 is --(CH 2) t --Y, C 1-6 alkyl, or C 3-6 cycloalkyl;R 1 is --CO 2 Z, C 1-6 alkyl, CH 2 OH, --CONHR y, or CHO;R 2 and R 3 are independently hydrogen or C 1-6 alkyl;R a and R b are independently hydrogen or C 1-6 alkyl; but when n is one, R a and R b together can form a radical of the formula STR2 Y is naphthyl or phenyl, both radicals can be optionally substituted with one to three same or different C 1-6 alkyl or halogen;Z is hydrogen or C 1-6 alkyl;R 5, R 6 and R y are independently hydrogen or C 1-6 alkyl; andt is zero to six.
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(2008/06/13)

Retinoid-like compounds
The present invention relates to a compound of formula STR1 or a nontoxic pharmaceutically acceptable salt, physiologically hydrolyzable ester or solvate thereof, in which X is --O--CO--, --NH--CO--, --CS--NH--, --CO--O--, --CO--NH--, --COS--, --SCO--, --SCH2 --, --CH2 --CH2 --, --C C--, --CH2 --NH--, --COCH2 --, --NHCS--, --CH2 S--, --CH2 O--, --OCH2 --, --NHCH2 -- or --CR5 =CR6 --; Rm and Rk are independently hydrogen, halogen, C1-6 alkyl, hydroxy, C1-6 alkyloxy or nitro; n is zero or one; R4 is --(CH2)t --Y, C1-6 alkyl, or C3-6 cycloalkyl; R1 is --CO2 Z, C1-6 alkyl, CH2 OH, --CONHRy, or CHO; R2 and R3 are independently hydrogen or C1-6 alkyl; Ra and Rb are independently hydrogen or C1-6 alkyl; but when n is one, Ra and Rb together can form a radical of the formula STR2 Y is naphthyl or phenyl, both radicals can be optionally substituted with one to three same or different C1-6 alkyl or halogen; Z is hydrogen or C1-6 alkyl; R5, R6 and Ry are independently hydrogen or C1-6 alkyl; and t is zero to six.
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(2008/06/13)

Orally active β-lactam inhibitors of human leukocyte elastase. 2. Effect of C-4 substitution
The effect of changing the C-4 substituent of 3,3-diethyl-1- [(benzylamino)carbonyl]-2-azetidinone on inhibition of HLE and in a model of HLE-induced lung damage in hamsters was explored. Substituents at this position do not appear to interact strongly with HLE with the most potent compounds having k(obs)/[I] = 6900 M-1 s-1. However, substituents at this position had a marked effect on in vivo activity. The greatest oral activity in the lung hemorrhage assay was achieved with C-4 aryl carboxylic acid ethers (60-85% inhibition at 30 mg/kg po). Based upon the established mechanism of inhibition by these compounds, the C-4 substituent would be released, and therefore, the pharmacological potential of these C-4 substituents was of considerable concern. Fortunately, compounds containing 4-hydroxybenzoic acid and 4-hydroxyphenylacetic acid ethers at C-4 were among the most active analogs. These phenolic acids are also found as urinary metabolites in healthy humans. Other heteroaryls at C-4 were also orally active in this model despite relatively modest enzyme activity.
Hagmann,Kissinger,Shah,Finke,Dorn,Brause,Ashe,Weston,Maycock,Knight,Dellea,Fletcher,Hand,Osinga,Davies,Doherty
p. 771 - 777
(2007/10/02)

Tetralin esters of phenols or benzoic acids having retinoid like activity
Retinoid-like activity is exhibited by compounds of the formula STR1 where the R groups are independently hydrogen, or lower alkyl; A is --C(O)O--, --OC(O)--, --C(O)S--, or --SC(O)--; n is 0-5; and Z is H, --COB where B is --OH or a pharmaceutically acceptable salt, or B is --OR 1 where R 1 is an ester-forming group, or B is --N(R) 2 where R is hydrogen or lower alkyl, or Z is --OE where E is hydrogen or an ether-forming group or --COR 2 where R 2 is hydrogen, lower alkyl, phenyl or lower alkyl phenyl, or Z is --CHO or an acetal derivative thereof, or Z is --COR 3 where R 3 is --(CH 2) m CH 3 where m is 0-4 and the sum of n and m does not exceed 4.
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(2008/06/13)

Orally Active β-Lactam Inhibitors of Leukocyte Elastase-1. Activity of 3,3-Diethyl-2-azetidinones
A thorough analysis of the mechanism of inhibition of human leukocyte elastase (HLE) by a monocyclic β-lactam and the mechanism of β-lactam hydrolysis led to the preparation of potent and highly stable inhibitors of HLE.This work led to the identification of 4--3,3-diethyl-1-carbonyl>-2-azetidinone (2) as the first orally active inhibitor of human leukocyte elastase (HLE).Analogs of 2 with different substituents on the urea N were synthesized and evaluated for their activity in vitro against HLE as well as in vivo in a hamster lung hemorrhage model.Compounds with a methyl or a methoxy group in the para position of the benzene ring were very potent in both assays.The results are discussed on the basis of the proposed model for the binding of this class of inhibitors to HLE and a possible mechanism of inhibition is presented.
Shah, Shrenik K.,Dorn, Conrad P.,Finke, Paul E.,Hale, Jeffrey J.,Hagmann, William K.,et al.
p. 3745 - 3754
(2007/10/02)

ELECTROCHEMICAL TRANSACYLATIONS: A MILD SYNTHESIS OF ESTERS
Esters can be synthesized by electrochemically oxidizing hydroquinone carboxylates in the presence of alcohols.High yields are obtained in acidic or basic solutions and at low temperatures.
Johnson, Richard W.,Bednarski, M. D.,O' Leary, B. F.,Grover, E. R.
p. 3715 - 3718
(2007/10/02)