cas 56441-55-5, ETHYL 4-(BENZYLOXY)BENZOATE

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Design, synthesis, and biological activity evaluation of 2-(benzo[b]thiophen-2-yl)-4-phenyl-4,5-dihydrooxazole derivatives as broad-spectrum antifungal agents
To discover antifungal compounds with broad-spectrum and stable metabolism, a series of 2-(benzo[b]thiophen-2-yl)-4-phenyl-4,5-dihydrooxazole derivatives was designed and synthesized. Compounds A30-A34 exhibited excellent broad-spectrum antifungal activity against Candida albicans with MIC values in the range of 0.03–0.5 μg/mL, and against Cryptococcus neoformans and Aspergillus fumigatus with MIC values in the range of 0.25–2 μg/mL. In addition, compounds A31 and A33 showed high metabolic stability in human liver microsomes in vitro, with the half-life of 80.5 min and 69.4 min, respectively. Moreover, compounds A31 and A33 showed weak or almost no inhibitory effect on the CYP3A4 and CYP2D6. The pharmacokinetic evaluation in SD rats showed that compound A31 had suitable pharmacokinetic properties and was worthy of further study.
Zhao, Liyu,Sun, Yin,Yin, Wenbo,Tian, Linfeng,Sun, Nannan,Zheng, Yang,Zhang, Chu,Zhao, Shizhen,Su, Xin,Zhao, Dongmei,Cheng, Maosheng
(2021/11/22)

Transition-Metal-Free and Base-Promoted Carbon-Heteroatom Bond Formation via C-N Cleavage of Benzyl Ammonium Salts
A facile and general method for constructing carbon-heteroatom (C-P, C-O, C-S, and C-N) bonds via C-N cleavage of benzyl ammonium salts under transition-metal-free conditions was reported. The combination of t-BuOK and 18-crown-6 enabled a wide range of substituted benzyl ammonium salts to couple readily with different kinds of heteroatom nucleophiles, i.e. hydrogen phosphoryl compounds, alcohols, thiols, and amines. Good functional group tolerance was demonstrated. The scale-up reaction and one-pot synthesis were also successfully performed.
Liu, Long,Tang, Yuanyuan,Wang, Kunyu,Huang, Tianzeng,Chen, Tieqiao
p. 4159 - 4170
(2021/03/09)

4-Alkyl-1,2,4-triazole-3-thione analogues as metallo-β-lactamase inhibitors
In Gram-negative bacteria, the major mechanism of resistance to β-lactam antibiotics is the production of one or several β-lactamases (BLs), including the highly worrying carbapenemases. Whereas inhibitors of these enzymes were recently marketed, they only target serine-carbapenemases (e.g. KPC-type), and no clinically useful inhibitor is available yet to neutralize the class of metallo-β-lactamases (MBLs). We are developing compounds based on the 1,2,4-triazole-3-thione scaffold, which binds to the di-zinc catalytic site of MBLs in an original fashion, and we previously reported its promising potential to yield broad-spectrum inhibitors. However, up to now only moderate antibiotic potentiation could be observed in microbiological assays and further exploration was needed to improve outer membrane penetration. Here, we synthesized and characterized a series of compounds possessing a diversely functionalized alkyl chain at the 4-position of the heterocycle. We found that the presence of a carboxylic group at the extremity of an alkyl chain yielded potent inhibitors of VIM-type enzymes with Ki values in the μM to sub-μM range, and that this alkyl chain had to be longer or equal to a propyl chain. This result confirmed the importance of a carboxylic function on the 4-substituent of 1,2,4-triazole-3-thione heterocycle. As observed in previous series, active compounds also preferentially contained phenyl, 2-hydroxy-5-methoxyphenyl, naphth-2-yl or m-biphenyl at position 5. However, none efficiently inhibited NDM-1 or IMP-1. Microbiological study on VIM-2-producing E. coli strains and on VIM-1/VIM-4-producing multidrug-resistant K. pneumoniae clinical isolates gave promising results, suggesting that the 1,2,4-triazole-3-thione scaffold worth continuing exploration to further improve penetration. Finally, docking experiments were performed to study the binding mode of alkanoic analogues in the active site of VIM-2.
Gavara, Laurent,Legru, Alice,Verdirosa, Federica,Sevaille, Laurent,Nauton, Lionel,Corsica, Giuseppina,Mercuri, Paola Sandra,Sannio, Filomena,Feller, Georges,Coulon, Rémi,De Luca, Filomena,Cerboni, Giulia,Tanfoni, Silvia,Chelini, Giulia,Galleni, Moreno,Docquier, Jean-Denis,Hernandez, Jean-Fran?ois
supporting information

(2021/06/15)

1,2,4-Triazole-3-thione compounds with a 4-ethyl alkyl/aryl sulfide substituent are broad-spectrum metallo-β-lactamase inhibitors with re-sensitization activity
Metallo-β-lactamases (MBLs) are important contributors of Gram-negative bacteria resistance to β-lactam antibiotics. MBLs are highly worrying because of their carbapenemase activity, their rapid spread in major human opportunistic pathogens while no clinically useful inhibitor is available yet. In this context, we are exploring the potential of compounds based on the 1,2,4-triazole-3-thione scaffold as an original ligand of the di-zinc active sites of MBLs, and diversely substituted at its positions 4 and 5. Here, we present a new series of compounds substituted at the 4-position by a thioether-containing alkyl chain with a carboxylic and/or an aryl group at its extremity. Several compounds showed broad-spectrum inhibition with Ki values in the μM to sub-μM range against VIM-type enzymes, NDM-1 and IMP-1. The presence of the sulfur and of the aryl group was important for the inhibitory activity and the binding mode of a few compounds in VIM-2 was revealed by X-ray crystallography. Importantly, in vitro antibacterial susceptibility assays showed that several inhibitors were able to potentiate the activity of meropenem on Klebsiella pneumoniae clinical isolates producing VIM-1 or VIM-4, with a potentiation effect of up to 16-fold. Finally, a selected compound was found to only moderately inhibit the di-zinc human glyoxalase II, and several showed no or only moderate toxicity toward several human cells, thus favourably completing a promising behaviour.
Becker, Katja,Benvenuti, Manuela,Bossis, Guillaume,Conde, Pierre-Alexis,Crowder, Michael W.,Dillenberger, Melissa,Docquier, Jean-Denis,Gavara, Laurent,Hernandez, Jean-Fran?ois,Legru, Alice,Mangani, Stefano,Pozzi, Cecilia,Sannio, Filomena,Tassone, Giusy,Thomas, Caitlyn A.,Verdirosa, Federica
supporting information

(2021/10/12)

4-Amino-1,2,4-triazole-3-thione-derived Schiff bases as metallo-β-lactamase inhibitors
Resistance to β-lactam antibiotics in Gram-negatives producing metallo-β-lactamases (MBLs) represents a major medical threat and there is an extremely urgent need to develop clinically useful inhibitors. We previously reported the original binding mode of 5-substituted-4-amino/H-1,2,4-triazole-3-thione compounds in the catalytic site of an MBL. Moreover, we showed that, although moderately potent, they represented a promising basis for the development of broad-spectrum MBL inhibitors. Here, we synthesized and characterized a large number of 4-amino-1,2,4-triazole-3-thione-derived Schiff bases. Compared to the previous series, the presence of an aryl moiety at position 4 afforded an average 10-fold increase in potency. Among 90 synthetic compounds, more than half inhibited at least one of the six tested MBLs (L1, VIM-4, VIM-2, NDM-1, IMP-1, CphA) with Ki values in the μM to sub-μM range. Several were broad-spectrum inhibitors, also inhibiting the most clinically relevant VIM-2 and NDM-1. Active compounds generally contained halogenated, bicyclic aryl or phenolic moieties at position 5, and one substituent among o-benzoic, 2,4-dihydroxyphenyl, p-benzyloxyphenyl or 3-(m-benzoyl)-phenyl at position 4. The crystallographic structure of VIM-2 in complex with an inhibitor showed the expected binding between the triazole-thione moiety and the dinuclear centre and also revealed a network of interactions involving Phe61, Tyr67, Trp87 and the conserved Asn233. Microbiological analysis suggested that the potentiation activity of the compounds was limited by poor outer membrane penetration or efflux. This was supported by the ability of one compound to restore the susceptibility of an NDM-1-producing E. coli clinical strain toward several β-lactams in the presence only of a sub-inhibitory concentration of colistin, a permeabilizing agent. Finally, some compounds were tested against the structurally similar di-zinc human glyoxalase II and found weaker inhibitors of the latter enzyme, thus showing a promising selectivity towards MBLs.
Baud, Damien,Bebrone, Carine,Becker, Katja,Benvenuti, Manuela,Cerboni, Giulia,Chelini, Giulia,Cutolo, Giuliano,De Luca, Filomena,Docquier, Jean-Denis,Feller, Georges,Fischer, Marina,Galleni, Moreno,Gavara, Laurent,Gresh, Nohad,Kwapien, Karolina,Legru, Alice,Mangani, Stefano,Mercuri, Paola,Pozzi, Cecilia,Sannio, Filomena,Sevaille, Laurent,Tanfoni, Silvia,Verdirosa, Federica,Berthomieu, Dorothée,Bestgen, Beno?t,Frère, Jean-Marie,Hernandez, Jean-Fran?ois
supporting information

(2020/09/16)

Development and application of a high-throughput screening assay for identification of small molecule inhibitors of the P. falciparum reticulocyte binding-like homologue 5 protein
The P. falciparum parasite, responsible for the disease in humans known as malaria, must invade erythrocytes to provide an environment for self-replication and survival. For invasion to occur, the parasite must engage several ligands on the host erythrocyte surface to enable adhesion, tight junction formation and entry. Critical interactions include binding of erythrocyte binding-like ligands and reticulocyte binding-like homologues (Rhs) to the surface of the host erythrocyte. The reticulocyte binding-like homologue 5 (Rh5) is the only member of this family that is essential for invasion and it binds to the basigin host receptor. The essential nature of Rh5 makes it an important vaccine target, however to date, Rh5 has not been targeted by small molecule intervention. Here, we describe the development of a high-throughput screening assay to identify small molecules which interfere with the Rh5-basigin interaction. To validate the utility of this assay we screened a known drug library and the Medicines for Malaria Box and demonstrated the reproducibility and robustness of the assay for high-throughput screening purposes. The screen of the known drug library identified the known leukotriene antagonist, pranlukast. We used pranlukast as a model inhibitor in a post screening evaluation cascade. We procured and synthesised analogues of pranlukast to assist in the hit confirmation process and show which structural moieties of pranlukast attenuate the Rh5 – basigin interaction. Evaluation of pranlukast analogues against P. falciparum in a viability assay and a schizont rupture assay show the parasite activity was not consistent with the biochemical inhibition of Rh5, questioning the developability of pranlukast as an antimalarial. The high-throughput assay developed from this work has the capacity to screen large collections of small molecules to discover inhibitors of P. falciparum Rh5 for future development of invasion inhibitory antimalarials.
Sleebs, Brad E.,Jarman, Kate E.,Frolich, Sonja,Wong, Wilson,Healer, Julie,Dai, Weiwen,Lucet, Isabelle S.,Wilson, Danny W.,Cowman, Alan F.
p. 188 - 200
(2020/11/05)

Boron-Catalyzed O-H Bond Insertion of α-Aryl α-Diazoesters in Water
A catalytic, metal-free O-H bond insertion of α-diazoesters in water in the presence of B(C6F5)3·nH2O (2 mol %) was developed, affording a series of α-hydroxyesters in good to excellent yields. The reaction features easy operation and wide substrate scope, and importantly, no metal is needed as compared with the conventional methods. Significantly, this approach further expands the applications of B(C6F5)3 under water-tolerant conditions.
San, Htet Htet,Wang, Shi-Jun,Jiang, Min,Tang, Xiang-Ying
supporting information
p. 4672 - 4676
(2018/08/09)

1,2,4-Triazole-3-thione Compounds as Inhibitors of Dizinc Metallo-β-lactamases
Metallo-β-lactamases (MBLs) cause resistance of Gram-negative bacteria to β-lactam antibiotics and are of serious concern, because they can inactivate the last-resort carbapenems and because MBL inhibitors of clinical value are still lacking. We previously identified the original binding mode of 4-amino-2,4-dihydro-5-(2-methylphenyl)-3H-1,2,4-triazole-3-thione (compound IIIA) within the dizinc active site of the L1 MBL. Herein we present the crystallographic structure of a complex of L1 with the corresponding non-amino compound IIIB (1,2-dihydro-5-(2-methylphenyl)-3H-1,2,4-triazole-3-thione). Unexpectedly, the binding mode of IIIB was similar but reverse to that of IIIA. The 3 D structures suggested that the triazole–thione scaffold was suitable to bind to the catalytic site of dizinc metalloenzymes. On the basis of these results, we synthesized 54 analogues of IIIA or IIIB. Nineteen showed IC50 values in the micromolar range toward at least one of five representative MBLs (i.e., L1, VIM-4, VIM-2, NDM-1, and IMP-1). Five of these exhibited a significant inhibition of at least four enzymes, including NDM-1, VIM-2, and IMP-1. Active compounds mainly featured either halogen or bulky bicyclic aryl substituents. Finally, some compounds were also tested on several microbial dinuclear zinc-dependent hydrolases belonging to the MBL-fold superfamily (i.e., endonucleases and glyoxalase II) to explore their activity toward structurally similar but functionally distinct enzymes. Whereas the bacterial tRNases were not inhibited, the best IC50 values toward plasmodial glyoxalase II were in the 10 μm range.
Sevaille, Laurent,Gavara, Laurent,Bebrone, Carine,De Luca, Filomena,Nauton, Lionel,Achard, Maud,Mercuri, Paola,Tanfoni, Silvia,Borgianni, Luisa,Guyon, Carole,Lonjon, Pauline,Turan-Zitouni, Gülhan,Dzieciolowski, Julia,Becker, Katja,Bénard, Lionel,Condon, Ciaran,Maillard, Ludovic,Martinez, Jean,Frère, Jean-Marie,Dideberg, Otto,Galleni, Moreno,Docquier, Jean-Denis,Hernandez, Jean-Fran?ois
p. 972 - 985
(2017/06/27)

Nonsymmetrical cholesterol dimers constituting regioisomeric oxadiazole and thiadiazole cores: an investigation of the structure-property correlation
Three series of chiral nonsymmetrical dimers were prepared by connecting promesogenic cholesterol to a bent structure derived from a substituted 1,3,4-oxadiazole or 1,2,4-oxadiazole or 1,3,4-thiadiazole moiety. These two mesogenic segments are interconnected through spacers of varying lengths and parity. The structures of the bent achiral unit were systematically varied with different central heterocyclic cores to understand the influence of bent angles on the thermal and gelation behavior. The bent angle of the achiral unit, which is determined by the heterocyclic core, has a major role in the stabilization of frustrated phases. Dimers based on the 1,3,4-oxadiazole unit with a more bent structure stabilized frustrated phases like blue phases and twist grain boundary phases. The bent system with a wider bent angle preferred to stabilize chiral nematic and smectic A phases. It is interesting to note that an increased bent structure reduced the mesophase stability as in the case of dimers based on the 1,3,4-oxadiazole unit, where many compounds exhibited monotropic phases. In the case of dimers with a wider bent angle, enantiotropic mesomorphism was observed. All the compounds showed blue light emission in the solution. Among these chiral dimers, only the compounds based on the 1,3,4-oxadiazole unit showed the gelation ability, which emphasizes how small structural changes like bent angle, dipole moment and the type of heteroatom in the heterocyclic unit affect the macroscopic self-assembly.
Pradhan, Balaram,Chakraborty, Nirmalangshu,Gupta, Ravindra Kumar,Shanker,Achalkumar, Ammathnadu S.
supporting information
p. 879 - 888
(2017/02/05)

Synthesis and anticonvulsant activity evaluation of 4-butyl-5-(4- alkoxyphenyl)-2H-1,2,4-triazole-3(4H)-ones
A series of 4-butyl-5-(4-alkoxyphenyl)-2H-1,2,4-triazole-3(4H)-ones (6a-6u) was designed and synthesized. The anticonvulsant effects and neurotoxicity of the compounds were evaluated with maximal electroshock test and rotarod test. Among the synthetic compounds, 4-butyl-5-(4-(2-fluorinebenzyl)phenyl)-2H-1,2,4- triazole-3 (4H)-one (6k) was the most potent with ED50 value of 27.4 mg/kg and protective index (PI = TD50/ED50) value of 12.0. Besides the anti-MES efficacy, the potency of compound 6k against seizures induced by pentylenetetrazole (PTZ), 3-mercaptopropionic acid (3-MP), and bicuculline (BIC) was also established, which suggested that the mechanisms of action including enhancing of GABAergic activity might be involved in its anticonvulsant activity.
Zhu, Zi-Shi,Wang, Shi-Ben,Deng, Xian-Qing,Liu, Da-Chuan,Quan, Zhe-Shan
p. 628 - 635
(2014/05/20)

SYNTHESIS AND ANTICANCER ACTIVITY OF ARYL AND HETEROARYL-QUINOLIN DERIVATIVES
A compound of Formula I is disclosed as follows: or a pharmaceutically acceptable salt, prodrug, solvate, or metabolite thereof, wherein R is hydrogen, P(═O)(OH)2, P(═O)(O(C1-C18)alkylene(C6-C20)aryl)2, P(═O)(OH)(OM), P(═O)(OM)2, P═O(O2M), S(═O)(OH)2, S(═O)(O(C1-C18)alkylene(C6-C20)aryl)2, S(═O)(OH)(OM), S(═O)(OM)2; M is a monovalent or divalent metal ion, or alkylammonium ion; W is (C6-C20)aryl, (C6-C20)heteroaryl, (C1-C18)alkyl(C6-C20)aryl, (C1-C18)alkyl(C6-C20)heteroaryl, hydroxy(C6-C20)aryl, hydroxy(C6-C20)heteroaryl, (C1-C18)alkoxy(C6-C20)aryl, (C1-C18)alkoxy(C6-C20)heteroaryl, (C1-C18)alkylenedioxy(C6-C20)aryl, (C1-C18)alkylenedioxy(C6-C20)heteroaryl, halo(C6-C20)aryl, halo(C6-C20)heteroaryl, (C1-C18)alkylamino(C6-C20)aryl, (C1-C18)alkylamino(C6-C20)heteroaryl, (C1-C18)cycloalkylamino(C6-C20)aryl, or (C1-C18)cycloalkylamino(C6-C20)heteroaryl, and their OR8 substutes; R5 is (C1-C18alkoxy, hydrogen, hydroxyl, O—(C1-C18)alkyl(C6-C20)aryl, halo or OR8, or R5 and R6 are (C1-C18)dioxy provided that R7 is hydrogen; R6 is hydroxyl, O—(C1-C18)alkyl(C6-C20)aryl, halo or ORR, (C1-C18)alkoxy, (C1-C18)alkylamino, or (C1-C18)cycloalkylamino, or R6 and R7 are (C1-C18)dioxy provided that R5 is hydrogen; R7 is hydrogen, halo or OR8, hydroxyl, or O—(C1-C18)alkyl(C6-C20)aryl; and R8 is P(═O)(OH)2, P(═O)(O(C1-C18)alkyl(C6-C20)aryl)2, P(═O)(OH)(OM), or P(═O)(OM)2, P═O(O2M).
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Page/Page column 25

(2012/02/01)

Synthesis and antibaterial activities of bis[(3-benzyloxypheny1)-1,2,4- triazolo[3,4-b]-[1,3,4]thiadiazole derivatives
Bis[(3-benzyloxyphenyl)-1,2,4-triazolo[3,4-b]-[1,3,4]thiadiazole derivatives 3 were synthesized in high yields by reaction of 3-benzyloxyphenyl-4-amino-5-mercapto-1,2,4-triazole 1 with dicarboxylic acid 2 in the presence of POCl3 and tetrabutylammonium iodide as catalyst. The preliminary antibacterial tests showed that most of them were effective against S. aureus, E.coli and B.subtilis.
Hu, Lang-Xi,Li, De-Jiang
scheme or table
p. 73 - 77
(2011/06/24)

2,6-Diphenylthiazolo[3,2-b][1,2,4]triazoles as telomeric G-quadruplex stabilizers
The design and synthesis of 2,6-diphenylthiazolo[3,2-b][1,2,4]triazoles characterized by a large aromatic building block bearing cationic side chains are reported. These molecules are evaluated as telomeric G-quadruplex stabilizers and for their selectivi
El Bakali, Jamal,Klupsch, Frederique,Guedin, Aurore,Brassart, Bertrand,Fontaine, Gaelle,Farce, Amaury,Roussel, Pascal,Houssin, Raymond,Bernier, Jean-Luc,Chavatte, Philippe,Mergny, Jean-Louis,Riou, Jean-Francois,Henichart, Jean-Pierre
scheme or table
p. 3434 - 3438
(2010/04/26)

Soluble and polymer-supported 2- and 3-benzylated furans for the preparation of α,β-ethylenic carbonyl compounds
Soluble and polymer-supported 2- and 3-benzylated furans were subjected to a sequence involving a Diels-Alder reaction with α,β-acetylenic carbonyl compounds, a Michael addition, and a subsequent retro-Diels-Alder reaction to yield olefinic compounds. On solid support, this traceless strategy is advantageous since pure compounds were released in the thermal cycloreversion step. The fur-2-ylated resin allowed a highly diastereoselective synthesis.
Albert, Sébastien,Soret, Adrien,Blanco, Luis,Deloisy, Sandrine
p. 2888 - 2900
(2007/10/03)

PESTICIDAL SUBSTITUTED PHENYLETHERS
The invention relates to the use of phenylether derivatives of formula (I), to compositions thereof for the control of pests, including arthropods and helminths.
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Page/Page column 42; 44

(2008/06/13)

Asymmetric synthesis of the pyran antibiotic (-)-centrolobine
An expedient total synthesis of (-)-centrolobine is achieved involving asymmetric Keck allylation and stereoselective intramolecular oxy-Michael reactions as key steps in 8% overall yield.
Chandrasekhar,Jaya Prakash,Shyamsunder
p. 6651 - 6653
(2007/10/03)

Peroxovanadium-catalyzed oxidative esterification of aldehydes
The peroxovanadium species generated from V2O5 and hydrogen peroxide, which is liberated from peroxy salts such as sodium perborate (SPB) or sodium percarbonate (SPC), transform aldehydes directly into esters in an alcoholic medium. Monoesters of diols have been achieved directly in one pot from aldehydes. High catalytic turnover number combined with inexpensive, easily available reagents and innocuous side products from the reaction make it a suitable alternative for the synthesis of esters from aldehydes.
Gopinath, Rangam,Barkakaty, Balaka,Talukdar, Bandana,Patel, Bhisma K.
p. 2944 - 2947
(2007/10/03)

Partially fluorinated liquid crystal material
The invention provides LC compositions that exhibit V-shaped switching when aligned in an analog device configuration and exhibit bistability when aligned in a bookshelf-type device configuration. The invention more specifically provides LC compositions of formula 1 and particularly chiral nonracemic compounds of formula 1 which exhibit bistable switching as well as V-shaped switching when aligned in appropriate device configurations. The invention also provides methods of using the compounds of the invention in making LC compositions and electooptical devices comprising an aligned layer of the compositions of this invention.
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(2008/06/13)

Helical Disubstituted Polyacetylenes: Synthesis and Chiroptical Properties of Poly(phenylpropiolate)s
Disubstituted polyacetylenes with helical chirality have been rarely prepared due to the involved synthetic difficulty, and we here report a facile polymerization system for the synthesis of such polymers. Two groups of chiral acetylenes, i.e., C6H5C≡CCO2R* {R* = [(1S)-endo]-(-)-borneyl (1), (1R,2S,5R)-(-)-menthyl (5), cholesteryl (6)} and C6H5C≡CCO2C 6H4CO2R* [R* = borneyl (2), menthyl (3), cholesteryl (4)], are prepared by esterifications of phenylpropiolic acids with borneol, menthol, and cholesterol. Polymerizations of 1-4 are effected by WCl6-Ph4Sn, giving poly(phenylpropiolate)s P1-P4 with high molecular weights in moderate yields. The structures and properties of the polymers are characterized and evaluated by IR, UV, NMR, CD, TGA, and SEM analyses. All the polymers are stable: neither decreases in their molecular weights nor changes in their spectra are detected after the polymers have been stored on shelf for ～3 years, and no weight losses are recorded when the polymers are heated to ～300 °C. Although the polymers do not possess regioregular Z or conformations, the polyacetylene backbones are induced to helically rotate by the chiral pendants, as verified by the strong Cotton effects in the backbone absorption region of the polymers (molar ellipticity up to 102 300 deg cm2 dmol-1). The polymers exhibit helical thermochromism, with their chain helicity being continuously and reversibly tunable by temperature change. The helical polymers are capable of self-assembling, as demonstrated by the formation of twisted ribbons upon diffusing a THF solution of P3 into hexane.
Lam, Jacky W.Y.,Dong, Yuping,Cheuk, Kevin K.L.,Tang, Ben Zhong
p. 7927 - 7938
(2007/10/03)

Novel chiral fluoro-substituted benzoyloxybenzoates exhibiting an antiferroelectric mesophase
The synthesis and properties of a new series of chiral fluoro-substituted benzoyloxybenzoates with nonchiral chains ranging from heptyloxy to octadecyloxy are reported. The mesomorphic properties of all of the compounds have been examined by a combination of optical polarized light microscopy, differential scanning calorimetry, and miscibility studies. They show rich polymorphism, and seven compounds exhibit the antiferroelectric (SmC*A) phase. The spontaneous polarization in the ferroelectric (SmC*) phase has been measured as a function of temperature for selected compounds.
Shubashree,Sadashiva,Dhara, Surajit
p. 21 - 32
(2007/10/03)

Solid phase Diels-Alder/retro Diels-Alder reactions. A new method for traceless linker strategy
A resin-bound furan has been efficiently synthesized from Merrifield resin. This new polymer reacts with an acetylenic dienophile to afford a thermally stable Diels-Alder adduct. Transformation of the adduct by Michael reaction with thiophenol has allowed an easy retro Diels-Alder reaction. This 'safety-catch' procedure leads to the formation of a chemically and stereochemically pure alkene and to the regeneration of the polymer-bound furan. (C) 2000 Elsevier Science Ltd.
Blanco,Bloch,Bugnet,Deloisy
p. 7875 - 7878
(2007/10/03)

Ferroelectric and antiferroelectric liquid crystalline phases in some pyridine carboxylic acid derivatives
The synthesis and mesomorphic properties of two series of compounds viz. (S)-(+)-4-(1-methylheptyloxy)phenyl 4′-(6″-alkoxypyridine-3-carbonyloxy)benzoatesand(S)-(+)-1- methylheptyl4-[4′-(6″-alkoxypyridine-3-carbonyloxy)benzoyIoxy]- benzoates are reported; the homologues of the former series exhibit smectic A and smectic C* phases while the derivatives of the latter series show rich polymesomorphism including the antiferroelectric phase. The mesophases have been characterised by using optical polarising microscopy and differential scanning calorimetric methods. Some physical properties such as the spontaneous polarisation, helical pitch, tilt angle and relative permittivity of two derivatives have also been investigated.
Kasthuraiah
p. 1619 - 1625
(2007/10/03)

Preparation of Dipyridylmethane Ligands with Pseudo-C2 Symmetry. Grafting on Polystyrenes via Transformation to Phenolic Derivatives
Efficient grafting of dipyridylmethane ligands on highly cross-linked as well as gel-type chloromethylated polystyrenes has been achieved using phenolic derivatives of the ligands.In this way, chiral polymer-supported ligands with pseudo-C2 symmetry were obtained.The synthesis of the ligands and their grafting under mild conditions are described, as well as the preparation of monomeric models.During reduction of 6,6'-(2,2-dimethyl-1-oxopropyl) derivatives with sodium borohydride, the R,S isomers were unexpectedly formed with high selectivity.
Levacher, Vincent,Moberg, Christina
p. 1755 - 1762
(2007/10/02)

5-[4-(Benzyloxy)phenyl]-1,3,4-oxadiazol-2(3H)-one derivatives and related analogues: New reversible, highly potent, and selective monoamine oxidase type B inhibitors
Thirty-three new 5-[4-(benzyloxy)phenyl]-1,3,4-oxadiazol-2(3H)-one derivatives including related analogues, designed as inhibitors of monoamine oxidase type B (MAO B), were synthesized and investigated both in vitro and ex vivo for their abilities to inhibit selectively rat brain MAO B over MAO A. Three inhibitors were found to act as reversible, highly potent, and selective MAO B inhibitors, namely the nitrile derivative 5-[4- (benzyloxy)phenyl]-3-(2-cyanoethyl)-1,3,4-oxadiazol-2(3H)-one (12a) and two closely related homologues, the corresponding oxadiazolethione 13a and the alcohol 14b. Their IC50(MAO B) values are in the low nanomolar range of 1.4-4.6 nM and their selectivities, estimated by the ratio of IC50 values (A/B), are from 3200 to >71 400. Compound 12a exhibited the highest activity against MAO B. Its IC50 was evaluated to be 1.4 nM with a quasitotal selectivity (>71 400) toward this enzyme. In ex vivo studies, 12a showed a reversible and short duration of action. MAO B was markedly inhibited with the oral dose of 1 mg/kg without any alteration of MAO A, and the inhibition almost did not exceed 24 h. Its ED50 (1 h after oral administration) was evaluated to be 0.56 mg (1.7 μmol)/kg. Remarkably, MAO A was not affected at doses as high as 1500 mg/kg, po. In addition, no apparent toxicity or behavioral anomaly was observed during the treatment even at the maximum administrated dose. SAR studies emphasize the existence of three binding sites to the enzyme with a special importance of the terminal phenyl. Analysis of the inhibition kinetics indicated that 12a acts in a two-step mechanism as a competitive, slow, and tight-binding inhibitor of MAO B with a K(i) value of 0.22 μM and an overall K(i)* value at equilibrium of 0.7 nM.
Mazouz,Gueddari,Burstein,Mansuy,Milcent
p. 1157 - 1167
(2007/10/02)

Arene-carboxylic acid derivatives as antiseborrheic additives for cosmetic agents
The invention concerns cosmetic agents containing compounds of the general formula (I) STR1 in which R1, R2 and R3 represent independently of one another a hydrogen atom, an intermediate alkyl group with 3 to 10 carbon atoms, a halogen atom, preferably a chlorine atom, a hydroxy group, an aryl group, an alkoxy group with 1 to 20 carbon atoms, substituted, if needed, with aryl, hydroxy, amino, alkoxy as well as aryloxy groups, or a carboxyl group esterified with an intermediate-chain alkyl group with 2 to 12 carbon atoms or with an aralkyl group, or two of the radicals R1 --R3 represent a naphthalene ring together with the benzene ring, and Y stands for an alkoxy group with 1 to 12 carbon atoms or an aralkoxy group. The compounds are used in amounts of 0.01 to 20, preferably 1 to 10, percent by weight, calculated with regard to the total preparation.
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(2008/06/13)

Hypolipidemic analogues of ethyl 4 benzyloxybenzoate
A series of compounds related to ethyl 4-benzyloxybenzoate was synthesized and evaluated for potential hypolipidemic activity in rats. Structure-activity relationships are discussed in terms of cholesterol-lowering activity together with effects on body weight gain and liver lipids. A number of the compounds inhibited cholesterol and free fatty acid biosynthesis from [1-14C]acetate in rat liver slices in vitro. Ethyl 4-benzyloxybenzoate, ethyl 4-benzyloxybenzoic acid, ethyl 4-p-bromobenzyloxybenzoate, and ethyl 4-o-methoxybenzyloxyphenyl acetate exhibited the most favorable spectrum of activity.
Baggaley,Fears,Hindley,Morgan,Murrell,Thorne
p. 1388 - 1393
(2007/10/05)

Phenyl alkyleneoxy phenyl alkanoic acid esters
Pharmaceutical compositions having hypolipidaemic and/or hypoglycaemic activity, contain a substituted (4-carboxyphenoxy) phenyl alkane derivative.
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(2008/06/13)