cas 867-13-0, Triethyl phosphonoacetate | Articles data

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Pyridyl-Amides as a Multimode Self-Assembly Driver for the Design of a Stimuli-Responsive π-Gelator
An oligo(p-phenylenevinylene) (OPV) derivative connected to pyridyl end groups through an amide linkage (OPV-Py) resulted in a multistimuli-responsive π-gelator. When compared to the corresponding OPV π-gelator terminated by a phenyl-amide (OPV-Ph), the aggregation properties of OPV-Py were found to be significantly different, leading to multistimuli gelation and other morphological properties. The pyridyl moiety in OPV-Py initially interferes with the amide H-bonded assembly and gelation, however, protonation of the pyridyl moiety with trifluoroacetic acid (TFA) facilitated the formation of amide H-bonded assembly leading to gelation, which is reversible by the addition of N,N-diisopropyethylamine (DiPEA). Interestingly, addition of Ag+ ions to a solution of OPV-Py facilitated the formation of a metallo-supramolecular assembly leading to gelation. Surprisingly, ultrasound-induced gelation was observed when OPV-Py was mixed with a dicarboxylic acid (A1). A detailed study using different spectroscopic and microscopic experimental techniques revealed the difference in the mode of assembly in the two molecules and the multistimuli-responsive nature of the OPV-Py gelation.
Kartha, Kalathil K.,Praveen, Vakayil K.,Babu, Sukumaran Santhosh,Cherumukkil, Sandeep,Ajayaghosh, Ayyappanpillai
p. 2250 - 2256
(2015)
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One-pot synthesis and antimicrobial of novel 6-ethoxy-6-oxido-3-oxo(thioxo) (imino)-5-substituted-2,7-dihydro-1,2,4-triazolo[3,4-e][1,2,3]diazaphospholes
A series of novel 6-ethoxy-6-oxido-3-oxo(thioxo)(imino)-5-substituted-2,7-dihydro-1,2,4-triazolo[3,4-e][1,2,3]diazaphospholes 2a-f was synthesized and characterized by IR and NMR (1H, 13C, and 31P) spectroscopic analysis. The methodology developed was one-pot three-component reaction of ethyl bromoacetate, triethyl phosphite and carbo(thio)(amino)hydrazides. The synthesized compounds were screened for their antimicrobial activities. 6-Ethoxy-6-oxido-3-oxo(thioxo)-5-phenyl-2,5,7-trihydro-1,2,4-triazolo[3,4-e][1,2,3]diazaphospholes (2c,d) exhibited significantly higher antimicrobial effects against the tested bacterial and fungal strains compared to other compounds and standard drug.
Ali, Tarik E.,Assiri, Mohammed A.
p. 965 - 969
(2021)
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Enantioselective Michael addition to vinyl phosphonatesviahydrogen bond-enhanced halogen bond catalysis
An asymmetric Michael addition of malononitrile to vinyl phosphonates was accomplished by hydrogen bond-enhanced bifunctional halogen bond (XB) catalysis. NMR titration experiments were used to demonstrate that halogen bonding, with the support of hydrogen-bonding, played a key role in the activation of the Michael acceptors through the phosphonate group. This is the first example of the use of XBs for the activation of organophosphorus compounds in synthesis. In addition, the iodo-perfluorophenyl group proved to be a better directing unit than different iodo- and nitro-substituted phenyl groups. The developed approach afforded products with up to excellent yields and diastereoselectivities and up to good enantioselectivities.
Erkman, Kristin,J?rving, Ivar,Kaasik, Mikk,Kanger, T?nis,Mart?nova, Jevgenija,Metsala, Andrus
p. 7561 - 7568
(2021/06/09)

Regioselective Synthesis of Novel Functionalized Pyrano[2′,3′:4,5]pyrimido[1,6-b][1,2,4,5]triazaphosphepines
Abstract: The reactions of6-acetyl-3-amino-4-imino-7-methyl-5-phenyl-3,5-dihydro-4H-pyrano[2,3-d]pyrimidine with triethyl phosphite and some electrophilicreagents, namely 1,2-dibromoethane, oxalyl chloride, chloroacetyl chloride, andethyl chloroacetate, were studied. These one-pot three-component reactionsregioselectively afforded four new11-acetyl-2-ethoxy-10-methyl-12-phenylpyrano[2′,3′:4,5]pyrimido[1,6-b][1,2,4,5λ5]triazaphosphepin-2-ones in69–73% yields.
Ali,Assiri,Yahia,Zahran,Meselhy,Hussien
p. 79 - 84
(2021/03/04)

BRYOSTATIN COMPOUNDS FOR ENHANCEMENT OF IMMUNOTHERAPY
Provided herein is the use of bryostatin agents to selectively enhance expression, translocation and/or cell surface presentation of an antigen in target cells of interest to modulate immunogenicity of the target cells. Aspects of the methods include, administering an effective amount of a bryostatin agent to a subject to modulate immunogenicity of target cells. The subject methods include a method of treating cancer, including administering to a subject an effective amount of a bryostatin agent to enhance cell surface antigen or neoantigen presentation on target cells of the subject, and administering to the subject a therapeutically effective amount of a therapeutic agent that specifically binds the cell surface antigen to treat the subject for cancer. Aspects of the subject methods also include use of the bryostatin agents to sensitize the target cells to clearance by the subject's immune system.
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Page/Page column 95-96

(2020/12/07)

Synthesis method of triethyl phosphonoacetate
Relating to the field of organic compound synthesis, the invention provides a synthesis method of triethyl phosphonoacetate. Triethyl phosphate and ethyl chloroacetate are taken as the raw materials to carry out Michael arbuzov rearrangement reaction, thus obtaining triethyl phosphonoacetate. The chemical reaction formulas of the synthesis method are: CH2ClCOOH+C2H5OH to C4H7ClO2+H2O, C4H7ClO2+C6H15O3P to C8H17O5P+C2H5Cl. The method provided by the invention solves the problems of high energy consumption, high cost and low product purity in the traditional process, also solves the problem of byproduct application in a synthetic environment, and achieves good economic and social benefits.
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Paragraph 0017; 0019; 0021; 0024; 0026; 0029; 0031

(2017/08/27)

Alkyl phosphonate preparing method
The invention provides an alkyl phosphonate preparing method. The method comprises: performing an Arbuzov reaction on compound A and compound B in a continuous reaction apparatus, and continuously discharging the product obtained from the reaction from the continuous reaction apparatus during the reaction procedure, to obtain alkyl phosphonate. The reaction temperature in the reaction procedure is T1; either of compound A and compound B having a lower boiling point has a boiling point at a standard atmosphere pressure to be T2; T1 is higher than T2 by 10-40 DEG C; and the reaction pressure in the reaction procedure is 0.5-2.0 MPa. The preparing method in the invention may use halohydrocarbon having large steric hindrance and lower polarizability of carbon-halogen bond as compound A, thereby effectively expanding a selection range of substrate, and correspondingly expanding the types of alkyl phosphonate prepared by using the Arbuzov reaction.
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Paragraph 0040; 0041; 0042; 0043; 0044-0067; 0096; 0097

(2017/10/07)

Preparation of polycyclic compounds by intramolecular photospirocyclization and photocycloaddition reactions of 4-alkenyl-1-cyanonaphthalene derivatives
Photoreactions of 4-pentenyl-1-cyanonaphthalenes yield spirocyclic products along with [4?+?2] cycloadducts. Photoreactions of 5-phenyl derivatives produce a product having tricyclo[6.3.0.01,4]undecadiene skeleton. Formation of angular triquinanes takes place in photoreactions of cycloalkene-linked cyanonaphthalenes. The observation demonstrates that π–π arene ring interactions, steric hindrance, and suitable locations of reaction sites in syn and anti singlet exciplexes govern the modes followed in intramolecular photoreactions of 4-alkenyl-1-cyanonaphthalenes.
Maeda, Hajime,Wada, Hidenori,Mukae, Hirofumi,Mizuno, Kazuhiko
p. 29 - 41
(2016/11/16)

Design, synthesis and SAR study of novel sulfonylureas containing an alkenyl moiety
A series of sulfonylurea compounds was designed and synthesized via introducing an alkenyl moiety into the aryl-5 position and most title compounds exhibited enhanced antifungal activities and limited herbicidal activities compared with chlorsulfuron. Then, a CoMSIA calculation for antifungal activities was carried out to establish a 3D-QSAR model in which a cross-validated q2 of 0.585 and a correlation coefficient r2 of 0.989 were obtained. The derived model revealed that hydrophobic and electrostatic fields were the two most important factors for antifungal activity. Structure optimization was performed according to the CoMSIA model and compound 9z was found to be as potent as chlorothalonil in vitro against C. cornigerum, the pathogen of the wheat sharp eyespot disease. In order to study the fungicidal mechanism, 9z was successfully docked into yeast AHAS using a flexible molecular docking method and the resulting binding pattern was similar to that of chlorimuron-ethyl, indicating that the antifungal activity of compounds 9 was probably due to the inhibition of fungal AHAS.
Wei, Wei,Cheng, Dandan,Liu, Jingbo,Li, Yuxin,Ma, Yi,Li, Yonghong,Yu, Shujing,Zhang, Xiao,Li, Zhengming
p. 8356 - 8366
(2016/09/09)

Long-Range Reactivity Modulations in Geranyl Chloride Derivatives
Derivatives of geraniol are versatile synthetic intermediates that are useful for synthesizing a variety of terpenoid natural products; however, the results presented herein show that subtle differences in the structures of functionalized geranyl chlorides can significantly impact their abilities to function as effective electrophiles in synthetic reactions. A series of focused kinetics experiments identify specific structure-activity relationships that illustrate the importance not only of steric bulk, but also of electronic effects from distant regions of the molecules that contribute to their overall levels of reactivity. Computational modeling suggests that destabilization of the reactant by filled-filled orbital mixing events in some, but not all, conformations may be a critical contributor to these important electronic effects.
Reardon, Michael B.,Xu, Muyun,Tan, Qingzhe,Baumgartel, P. George,Augur, Danielle J.,Huo, Shuanghong,Jakobsche, Charles E.
p. 10964 - 10974
(2016/11/29)

Synthesis of new ligands for targeting the S1P1 receptor
Sphingosine-1-phosphate (S1P) influences various fundamental biological processes by interacting with a family of five G protein-coupled receptors (S1P1-5). FTY720, a sphingosine analogue, which was approved for treatment of relapsing forms of multiple sclerosis, is phosphorylated in vivo and acts as an agonist of four of the five S1P receptor subtypes. Starting from these lead structures we developed new agonists for the S1P1 receptor. The biological activity was tested in vivo and promising ligands were fluorinated at different positions to identify candidates for positron emission tomography (PET) imaging after [18F]-labelling. The radioligands shall enable the imaging of S1P1 receptor expression in vivo and thus may serve as novel imaging markers of S1P-related diseases.
Schilson, Stefanie S.,Keul, Petra,Shaikh, Rizwan S.,Sch?fers, Michael,Levkau, Bodo,Haufe, Günter
p. 1011 - 1026
(2015/03/04)

Applications of mesoporous titanium phosphonate functionalized with carboxylic groups
Mesoporous titanium phosphonate functionalized with -COOH was synthesized by a simple co-condensation process with the use of 2-phosphonoacetic acid and titanium tetrachloride under acid conditions. The obtained mesoporous materials show high surface area and large pore volume, which were supported by XRD, TEM, SEM and N2 adsorption analysis. The integrity of the organophosphonate groups were further characterized by FTIR and NMR. Palladium nanoparticles were successfully supported onto the materials combined with a metal adsorption-reduction procedure, showing high activity for the Suzuki reaction. Furthermore, the obtained catalyst can be recovered and reused without significant decrease in catalytic activity. This journal is
Li, Dongdong,Zhang, Yuping
p. 44229 - 44233
(2014/12/10)

NEW LIGANDS FOR TARGETING OF S1P RECEPTORS FOR IN VIVO IMAGING AND TREATMENT OF DISEASES
The present invention relates to novel compounds of formulae (I) and (II) which are useful in the prevention, treatment and diagnosis, in vivo diagnosis of diseases or disorders related to S1P receptors, in particular, in diseases which are connected to the regulatory function of sphingosine-1-phosphate (S1P) and its analogues, such as inflammation, pain, autoimmune diseases and cardiovascular diseases.
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Paragraph 0359; 0360; 0361; 0362

(2014/06/25)

Highly efficient preparation of selectively isotope cluster-labeled long chain fatty acids via two consecutive Csp3-Csp3 cross-coupling reactions
An efficient synthesis involving two copper-catalyzed alkyl-alkyl coupling reactions has been designed to easily access doubly isotope-labeled fatty acids. Such NMR- and IR-active compounds were obtained in excellent overall yields and will be further used for determining the conformation of an alkyl chain of lipidic biomolecules upon interaction with proteins.
Lethu, Sebastien,Matsuoka, Shigeru,Murata, Michio
supporting information
p. 844 - 847
(2014/03/21)

Simple synthesis of new 3-substituted 4-(3-chloro-4-fluorophenyl)-1h- pyrrole derivatives and their anticancer activity in vitro
The preparation of the new 3-substituted 4-(3-chloro-4-fluorophenyl)- 1H-pyrrole derivatives was based on the Van Leusen pyrrole synthesis. In this article, eighteen compounds were readily synthesized in satisfactory to good yields and their cell proliferation inhibiting activities against 2 normal cell lines and 16 cancer cell lines were evaluated. It was particularly important that the new pyrroles displayed barely cytotoxicity against the tested normal cell, which meant these pyrrole analogues might show excellent selectivity towards cancer cell and normal cell. Cell cycle analysis by flow cytometry (FCM) showed that the G0/G1 phase decreased a lot and S phase arrested, in between a minor and transient G2/M block was observed. Cell death induced by 3-cyano-4-(3-chloro-4- fluorophenyl)-1H-pyrrole (2r) was also verified by multiple methods.
Lan, Lan,Zhan, Xiaoping,Qin, Weixi,Liu, Zenglu,Maoa, Zhenmin
p. 375 - 397
(2014/03/21)

NEW LIGANDS FOR TARGETING OF S1P RECEPTORS FOR IN VIVO IMAGING AND TREATMENT OF DISEASES
The present invention relates to novel compounds of formulae (I) and (II) which are useful in the prevention, treatment and diagnosis, in vivo diagnosis of diseases or disorders related to S1P receptors, in particular, in diseases which are connected to the regulatory function of sphingosine-1-phosphate (S1P) and its analogues, such as inflammation, pain, autoimmune diseases and cardiovascular diseases.
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Page/Page column 45-46

(2013/03/26)

A catalytic Michael/Horner-Wadsworth-Emmons cascade reaction for enantioselective synthesis of thiochromenes
A catalytic enantioselective sulfa-Michael/Horner-Wadsworth-Emmons reaction cascade has been developed, taking advantage of phosphonate as an electrophilic activator and a traceless binding site. Using a chiral bifunctional urea derivative as the catalyst, a variety of aryl and heteroaryl substituted thiochromenes was obtained in excellent yield with a high level of enantioselectivity. Copyright
Choudhury, Abhijnan Ray,Mukherjee, Santanu
supporting information
p. 1989 - 1995
(2013/08/23)

Polylactic acid composition
It is an object of the present invention to provide a composition which contains polylactic acid and has excellent heat stability, mechanical strength and color. The composition contains 0.001 to 0.1 part by weight of a metal catalyst and 0.001 to 0.5 part by weight of a phosphono-fatty acid ester based on 100 parts by weight of polylactic acid.
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Page/Page column 8

(2012/09/22)

Lewis acid-mediated Michaelis-Arbuzov reaction at room temperature: A facile preparation of arylmethyl/heteroarylmethyl phosphonates
A facile preparation of arylmethyl and heteroarylmethyl phosphonate esters was achieved involving a Lewis acid mediated Michaelis-Arbuzov reaction at room temperature. Interaction of arylmethyl halides/alcohols with triethyl phosphite in the presence of Lewis acid at room temperature afforded phosphonate esters in good yields.
Rajeshwaran, Ganesan Gobi,Nandakumar, Meganathan,Sureshbabu, Radhakrishnan,Mohanakrishnan, Arasambattu K
supporting information; experimental part
p. 1270 - 1273
(2011/04/23)

Stereoselective control in the Staudinger reactions involving monosubstituted ketenes with electron acceptor substituents: Experimental investigation and theoretical rationalization
The stereoselectivity of the Staudinger reactions involving monosubstituted ketenes with electron acceptor substituents was investigated experimentally by determination of the product stereochemistry and theoretically via DFT calculations. The results indicate that imines preferentially attack the less sterically hindered exo-side of the ketenes to generate zwitterionic intermediates. Subsequently, for cyclic imines, the intermediates undergo a conrotatory ring closure directly to produce β-lactams, while for linear imines, the imine moiety of the intermediates isomerizes to more stable intermediates, which further undergo a conrotatory ring closure to afford trans-β-lactams. The steric hindrance and the isomerization, rather than the torquoelectronic effect, play crucial roles in controlling the stereoselectivity in the practical Staudinger reactions involving monosubstituted ketenes with electron acceptor substituents, although the unaccessible borylketene with a powerful electron acceptor group controls the stereoselectivity torquoelectronically, in theory.
Qi, Hengzhen,Li, Xinyao,Xu, Jiaxi
supporting information; experimental part
p. 2702 - 2714
(2011/05/19)

Cyclobutanone mimics of penicillins: Effects of substitution on conformation and hemiketal stability
(Chemical Equation Presented) The tendency for carbocyclic analogues of penicillins to undergo hydrate and hemiketal formation is central to their ability to function as β-lactamase inhibitors. 2-Thiabicyclo[3.2.0]heptan- 6-one-4-carboxylates with alkoxy functionality at C3 have been prepared through two complementary diastereoselective substitution reactions following a highly stereoselective chlorination with sulfuryl chloride. We have found that carbocyclic analogues with 3β substituents favor an endo envelope conformation in solution, the solid state, and the gas phase, whereas those with 3α substituents adopt an exo envelope. Evidence from X-ray crystal structures and ab initio calculations suggests that an anomeric effect contributes to the large conformational preference of the tetrahydrothiophene ring that favors the C3 substituent in an axial orientation. In addition, the envelope conformation of the bicycle, which is determined by the stereochemistry of the C3 substituent, has a dramatic effect on the ability of the cyclobutanone to undergo hemiketal formation in methanol-d4.
Johnson, Jarrod W.,Evanoff, Darryl P.,Savard, Marc E.,Lange, Gerald,Ramadhar, Timothy R.,Assoud, Abdeljalil,Taylor, Nicholas J.,Dmitrienko, Gary I.
supporting information; experimental part
p. 6970 - 6982
(2009/05/09)

Exploration of the molecular origin of the azinomycin epoxide: Timing of the biosynthesis revealed
(Equation Presented) Streptomyces sahachiroi whole cell feeding experiments, utilizing putative precursors labeled with stable isotopes, established that the epoxide unit of the DNA cross-linked agents, azinomycin A and B, proceeds via a valine-dependent pathway and that hydroxylation and dehydration precedes formation of the terminal epoxide. Sodium 3-methyl-2-oxobutenoate, formed through a transimination reaction, was shown to be the penultimate precursor incorporated into the azinomycin epoxide.
Sharma, Vasudha,Kelly, Gilbert T.,Watanabe, Coran M. H.
supporting information; experimental part
p. 4815 - 4818
(2009/05/31)

Advantages of organophosphorus synthesis in ionic liquids: "Green" approaches to useful phosphorus-substituted building blocks
Novel examples concerning the application of ionic liquids as a promoting reaction media in organophosphorus chemistry are discussed. Imidazolium ionic liquids were found to accelerate the Michaelis-Arbuzov reaction allowing to perform it under very mild conditions. Both phosphonium and imidazolium ILs give the possibility to perform easily direct amidation of phosphoryl acetic acids by various amines. Nucleophilic displacement reactionin a series of bromoalkylphosphonates was carried out in quantitative yield to afford azidoalkylphosphonates using the [bmim][PF6]/H2O system. Copyright Taylor & Francis Group, LLC.
Odinets,Matveeva,Sharova,Artyushin,Kozlov,Vorob'eva,Osipov,Roeschenthaler
scheme or table
p. 383 - 388
(2009/04/04)

Highly (E)-selective wadsworth-emmons reactions promoted by methylmagnesium bromide
(Chemical Equation Presented) An experimentally simple protocol for the very highly (E)-selective Wadsworth-Emmons reaction [(E):(Z) selectivities in excess of 180:1 in some cases] of a range of straight-chain and branched aliphatic, substituted aromatic, and base-sensitive aldehydes via reaction with an alkyl diethylphosphonoacetate and MeMgBr is reported.
Claridge, Timothy D. W.,Davies, Stephen G.,Lee, James A.,Nicholson, Rebecca L.,Roberts, Paul M.,Russell, Angela J.,Smith, Andrew D.,Toms, Steven M.
body text
p. 5437 - 5440
(2009/06/18)

ANTINEOPLASTIC AND CURCUMIN DERIVATIVES AND METHODS OF PREPARATION AND USE
This invention comprises antineoplastic curcumin derivatives and methods of preparation and use thereof. Note is made of the acylation product of the lithium enolate of β-ionone using the acid chloride, 2(E)-3-(2,6,6-trimethycyclohex-1-en-1-yl)propenoyl chloride derived from β-cyclocitral. Particular reference is made to the isomeric compound, 1-(2,6,6-trimethylcyclohex-2-en-1-yl)-7-(2,6,6-trimethylcyclohex-1-en-1-yl)- 1,6-heptadiene-3,5-dione.
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Page/Page column 9

(2010/11/28)

Ionic-liquid-promoted Michaelis-Arbuzov rearrangement
Room-temperature imidazolium ionic liquids, [Rmim][X], proved to be environmentally benign recyclable solvents promoting the Michaelis-Arbuzov rearrangement, which can be performed even at room temperature in a short period of time. The best ionic liquid of choice depended on the starting phosphorus(III) ester, namely, for triethyl phosphite [bmim][NTf2] demonstrated better results while for ethyl diphenylphosphinite it was [hmim][Br].
Matveeva,Odinets,Kozlov,Shaplov,Mastryukova
p. 7645 - 7648
(2007/10/03)

Preparation of [1,2,3,4,5-13C 5]-5-Amino-4-oxopentanoic Acid (ALA) - Design of a Synthetic Scheme to Prepare Any 13C- and 15N-Isotopomer with High Isotopic Enrichment
5-Amino-4-oxopentanoic acid (5-aminolevulinic acid) is a precursor in the biosynthesis of the biologically active porphyrins such as chlorophyll, bacteriochlorophyll, heme, etc. These systems are central in photosynthesis, oxygen transport, electron transport, etc. In this paper we describe a simple scheme to prepare any isotopomer of 5-aminolevulinic acid in a few steps in high yield. Using a similar scheme, levulinic acid can now also be prepared in any isotopomeric form. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
Shrestha-Dawadi, Prativa Bade,Lugtenburg, Johan
p. 4654 - 4663
(2007/10/03)

Copper-catalyzed formation of carbon-heteroatom and carbon-carbon bonds
The present invention relates to copper-catalyzed carbon-heteroatom and carbon-carbon bond-forming methods. In certain embodiments, the present invention relates to copper-catalyzed methods of forming a carbon-nitrogen bond between the nitrogen atom of an amide or amine moiety and the activated carbon of an aryl, heteroaryl, or vinyl halide or sulfonate. In additional embodiments, the present invention relates to copper-catalyzed methods of forming a carbon-nitrogen bond between a nitrogen atom of an acyl hydrazine and the activated carbon of an aryl, heteroaryl, or vinyl halide or sulfonate. In other embodiments, the present invention relates to copper-catalyzed methods of forming a carbon-nitrogen bond between the nitrogen atom of a nitrogen-containing heteroaromatic, e.g., indole, pyrazole, and indazole, and the activated carbon of an aryl, heteroaryl, or vinyl halide or sulfonate. In certain embodiments, the present invention relates to copper-catalyzed methods of forming a carbon-oxygen bond between the oxygen atom of an alcohol and the activated carbon of an aryl, heteroaryl, or vinyl halide or sulfonate. The present invention also relates to copper-catalyzed methods of forming a carbon-carbon bond between a reactant comprising a nucleophilic carbon atom, e.g., an enolate or malonate anion, and the activated carbon of an aryl, heteroaryl, or vinyl halide or sulfonate. Importantly, all the methods of the present invention are relatively inexpensive to practice due to the low cost of the copper comprised by the catalysts.
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(2015/03/06)

Process and intermediates for production of donepezil and related compounds
The present invention relates to a new process for the preparation of acetylcholinesterase inhibitors of formula (I) or a salt thereof, wherein: R1 is N-acyl-4-piperidyl; N-alkoxycarbonyl-4-piperidyl; N-alkyl-4-piperidyl; N-benzyl-4-piperidyl; N-(ω-aralkyl)-4-piperidyl; 4-pyridyl; R4, R5, R6, and R7 are identical or different and each represents hydrogen, straight-chain or branched alkyl, aryl, hydroxy, alkoxy, aryloxy, benzyloxy, acyloxy, alkylthio, arylthio, benzylthio, acylamino, phthalimido or halogen; n is 1, 2 or 3; m is 1, 2, 3, 4, or 5. This process comprises cyclisation of a compound of formula (II) or salts thereof, wherein R1, R4, R5, R6 and R7, m and n are as defined above; R2 is selected from a derivatised or non-derivatised carboxyl, cyano, N-substituted aminocarbonyl groups or hydrogen; R3 is selected from a derivatised or non-derivatised carboxyl, cyano or N-substituted aminocarbonyl groups, optionally in the presence of acids and/or solvents. One of the most potent acetylcholinesterase inhibitors of the class of compounds prepared according to the present invention is donepezil.
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(2008/06/13)

Synthesis and spectroscopic characterization of [1′-14C]ubiquinone-2, [1′-14C]-5-demethoxy-5-hydroxyubiquinone-2, and [1′-14C]-5-demethoxyubiquinone-2
[1′-14C]Ubiquinone-2, [1′-14C]-5-demethoxy-5-hydroxyubiquinone-2, and [1′-14C]-5-demethoxyubiquinone-2 have been synthesised from [1-14C]acetic acid. A common feature of these benzoquinones is the isoprenoid chain, and the 14C-label has therefore been incorporated in this isoprenoid. The coupling of the different quinone head groups and the isoprenoid chain is the last step in the total synthesis, to prevent unnecessary loss of the labelled material during synthesis. The products have been characterised by mass spectrometry, 1H NMR and 13C NMR.
Van Der Klei, Anita,De Jong, Robertus L. P.,Lugtenburg, Johan,Tielens, Aloysius G. M.
p. 3015 - 3023
(2007/10/03)

Synthesis and characterization of new symmetrical bisphosphonates
In order to search for new chelating agents, widely employed methodologies in the chemistry of organophosphorus compounds such as the Michaelis-Arbuzov and Michaelis-Becker reactions were used to synthesize new bisphosphonates in high yields. The importance of the synthesis of these compounds resides in their potential capability of complexing different metals, all the more so because bisphosphonates have been widely employed in the diagnosis and therapy of several bone diseases, such as osteoporosis and hypercalcemia, as extracting agents for alkaline, alkaline earth, and transition metals, and also as reaction catalysts. All bisphosphonates synthesized were characterized by IR, 1H-NMR, 13C-NMR, 31P-NMR, and mass spectroscopy.
Marques Rodrigues, Janaina,DaCosta, Joao Batista Neves
p. 137 - 149
(2007/10/03)

Synthesis and biological evaluation of cycloalkylidene carboxylic acids as novel effectors of Ras/Raf interaction
The protooncogenes Ras and Raf play important roles in signal transduction pathways regulated by mitogen-activated protein kinases. Mutations of Ras that arrest the protein in its active state are frequently implicated in tumor formation. We used Ras and Raf proteins in the yeast two-hybrid system to search for natural or synthesized substances capable of modulating Ras/Raf interaction by specifically binding to one of the interacting partners. We found that cycloalkylidene carboxylic acids enhanced Ras/Raf interaction by acting on the cysteine-rich domain of Raf. Several analogues of the active substance 2-cyclohexylidene propanoic acid were synthesized and the importance of the semicyclic double bond in the stabilization of Ras/Raf interaction was demonstrated. Variation of the size and the substituents of the cyclic system as well as the length of the carboxylic acid resulted in enhanced Ras/Raf interaction.
Friese, Anke,Hell-Momeni, Katja,Zündorf, Ilse,Winckler, Thomas,Dingermann, Theodor,Dannhardt, Gerd
p. 1535 - 1542
(2007/10/03)

Microwave irradiation in organophosphorus chemistry. III. Moderate scale synthesis of reagents for olefin formation
Representative phosphonates and phosphonium salts have been prepared on a moderate scale (25-50 g) using a domestic microwave oven. The reactions, conducted in sealed hydrogenation vessels, showed remarkable rate acceleration and excellent yields (>95%) employing this methodology.
Kiddle
p. 3377 - 3382
(2007/10/03)

Comparative spectroscopic and theoretical studies on the conformation of some α-diethoxyphosphoryl carbonyl compounds and their α-ethylsulfonyl analogues
Comparative vco IR analysis of β-carbonylphosphonates [XC(O)CH2P(O)(OR)2: X = Me 1, Ph 2, OEt 3, NEt2 4 and SEt 5; R = Et] (series I) and β-carbonylsulfones [XC(O)CH2SO2R: X = Me 6, Ph 7, OEt 8, NEt2 9 and SEt 10; R = Et] (series II) along with ab initio 6-31 G** calculations on la and 6a (R = Me) suggest the existence of only a single gauche conformer for series I. The negative carbonyl frequency shifts for both series follow approximately the electron-affinities of the π*co orbital of the parent compounds MeC(O)X 11-15. The less positive asymmetric sulfonyl frequency shifts (ΔvSO2) for II in relation to the phosphoryl frequency shifts (ΔvPO) for I and the larger negative carbonyl frequency shifts for II with respect to the corresponding values for I are in line with the upfield 13C NMR chemical shifts of the carbonyl carbon for II compared to I. These trends agree with the shorter O(SO2) ...C(CO) contact in comparison with the O(PO) ... C(CO) one and are discussed in terms of Olp→π*co charge transfer and electrostatic interactions, which are stronger for series II than for I, indicating that the sulfonyl oxygen atom is a better electron donor than the phosphoryl oxygen atom. Intrinsic geometrical parameters of O=S-CH2 and O=P-CH2 moieties seem to be responsible for this behaviour as indicated by X-ray study and ab initio calculations of dialkyl (methylsulfonyl)methylphosphonate MeSO2CH2P(O)(OR)2(R = Et l8, Me 18a). The Royal Society of Chemistry 2001.
Olivato, Paulo R.
p. 97 - 102
(2007/10/03)

Synthesis of the sex pheromone of Lygus lineolaris (Heteroptera miridae)
We propose a new synthesis of the sex pheromone of Lygus lineolaris (Heteroptera miridae) that uses a phase-transfer version of the Wittig - Horner reaction to produce a monoene synthon of the principal component of the pheromone, E-2-hexenylbutyrate.
Shakirzyanova,Abdukakharov,Abduvakhabov
p. 623 - 624
(2007/10/03)

Microwave irradiation in organophosphorus chemistry 1: The Michaelis-Arbuzov reaction
A diverse series of phosphonate esters have been prepared using a domestic microwave oven. The microwave enhanced Michaelis-Arbuzov reaction shows remarkable rate acceleration under microwave irradiation and allows the facile synthesis, and in certain cases easy workup, of alkyl, α-substituted and aryl phosphonates.
Kiddle, James J.,Gurley, Alison F.
p. 195 - 205
(2007/10/03)

Transformations of electrophilic reagents in a diethyl phosphite-potassium carbonate-ethanol system
Transformations of alkyl halides, aldehydes, and activated alkenes in a (EtO)2PHO-K2CO3-EtOH heterophase system were studied. The reactions are catalyzed by EtOK that formed and follow the known schemes of the interaction of hydrophosphoryl compounds with electrophiles.
Platonov, A. Yu.,Sivakov, A. A.,Chistokletov, V. N.,Maiorova, E. D.
p. 367 - 370
(2007/10/03)

Syntheses of strychnan- and aspidospermatan-type alkaloids. 10. An enantioselective synthesis of (-)-strychnine through the Wieland-Gumlich aldehyde
Condensations of L-tryptophan-derived 2-[(methoxycarbonyl)methyl]-3- [2(S)-(benzyloxycarbonyl)-2-(N(b)-benzylamino)ethyl]indole (6) with 4,4- dimethoxyacrolein or with 2,4-hexadienal, followed by removal of the tryptophanyl ester function, respectively gave the tetracyclic acetal (-)- methyl (2S,-3aS,5R,11bR)-3-benzyl-2,3,3a,4,5,7-hexahydro-5- (dimethoxymethyl)-1H-pyrrolol[2,3-d]carbazole-6-carboxylate (10) or the tetracyclic olefin (-)-methyl (2S,3aS,5R,11bR)-3-benzyl-2,3,3a,4,5,7- hexahydro-5-(1-propenyl)-1H-pyrrolo[2,3-d]carbazole-6-carboxylate (14). Their respective hydrolysis or oxidation provided, enantioselectively, the tetracyclic aldehyde (-)-methyl (2S,3aS,5R,11bR)-3-benzyl-2,3,3a,4,5,7- hexahydro-5-formyl-1H-pyrrolo[2,3-d]carbazole-6-carboxylate (5). Its reaction with tri-n-butyl-1-(ethoxy)ethoxymethyltin and n-butyllithium, followed by oxidation of the resultant alcohol (-)-methyl (2S,3aS,5R,11bR)-3-benzyl- 2,3,3a,4,5,7-hexahydro-5-(1ξ-hydroxy-2-((1-ethoxy-ethoxy))ethyl-1H- pyrrolo[2,3-d]carbazole-6-carboxylate (16) and cyclization furnished the pentacyclic ketone (-)-methyl (2S,3aS,SR,11bR)-3-benzyl-2,3,3a,4,5,7- hexahydro-3,5-ethano-12-oxo-1H-pyrrolo-[2,3-d]carbazole-6-carboxylate (15). A Horner-Emmons condensation led to the unsaturated esters (-)-methyl (2S,3aS,5R,11bR)-3-benzyl-2,3,3a,4,5,7-hexahydro-3,5-ethano-12-(E and Z)- [(methoxycarbonyl)-methylene]-1H-pyrrolo[2,3-d]carbazole-6-carboxylates (19 and 20) with 17:1 E/Z selectivity. Reductions of the ester and vinylegous urethane functions in 19 led to the Wieland-Gumlich aldehyde 3 as a 6:1 anomeric hemiacetal mixture. Its condensation with malonic acid provided (- )-strychnine (1) in 5.3% overall yield and 14 steps from the tryptophan derivative 6.
Kuehne, Martin E.,Xu, Feng
p. 9427 - 9433
(2007/10/03)

A new, effective approach for the C-C bond formation utilizing 1-, 2- and 3-phosphonyl substituted radicals derived from iodoalkylphosphonates and n-Bu3SnH/Et3B/O2 system
A new, practical synthesis of highly substituted phosphonates utilizing 1-, 2- and 3-phosphonyl substituted radicals derived from iodoalkylphosphonates and a catalytic or stoichiometric amounts of the n-Bu3SnH/Et3B/O2 reagent is described.
Balczewski,Pietrzykowski
p. 7291 - 7304
(2007/10/03)

A short and efficient enantioselective synthesis of cyclohexylnorstatine, a key component of a renin inhibitor
A catalytic asymmetric synthesis of ethyl (2R,35)-N-(p- toluenesulfonyl)-3-amino-4-cyclohexyl-2-hydroxybutyrate 7 in 96% ee from cheaply available cyclohexanone is described employing Sharpless asymmetric aminohydroxylation as the key step.
Upadhya,Sudalai
p. 3685 - 3689
(2007/10/03)

Asymmetric Synthesis of a Series of Chiral AB2 Monomers for Dendrimer Construction
Efficient preparation of a series of four chiral, nonracemic AB2 monomers suitable for the construction of dendrimers is presented. Monomers 1-4 possess the common structural features of a diphenolic moiety and a benzylic or aliphatic hydroxyl which render these molecules suitable for convergent dendrimer synthesis. The same basic, high-yielding, five-step sequence is employed for 1-4. Stilbene derivatives 13 and 14 are prepared by a Horner-Wadsworth-Emmons modified Wittig reaction between 3,5- or 3,4-bis(benzyloxy)benzaldehyde (8 and 10) and an ester-substituted benzylphosphonate (11 or 12). Cinnamate derivatives 21 and 22 are prepared similarly from 8 and 10 and triethyl phosphonoacetate. Chirality is introduced in the form of a 1,2-diol unit by Sharpless asymmetric dihydroxylation (AD) (>97% ee in all cases). Protection of the 1,2-diols as their acetonide derivatives provides dioxolane intermediates 17, 18, 25, and 26. Reduction of the ester groups followed by hydrogenolysis of the benzyl ethers yields AB2 monomers 1-4 in 57-67% overall yield from 8 and 10.
McElhanon, James R.,Wu, Mu-Jen,Escobar, Maya,Chaudhry, Umer,Hu, Chun-Ling,McGrath, Dominic V.
p. 908 - 915
(2007/10/03)

Oxazolidinedione derivatives and their use
Novel 2,4-oxazolidinedione compounds of the formula: STR1 wherein R is a hydrocarbon residue or a heterocyclic group each of which may be substituted; Y is --CO--, --CH(OH)-- or --NR3 -- (wherein R3 is an alkyl group which may be substituted); m is 0 or 1; n is 0, 1 or 2; X is CH or N; A is bivalent straight or branched hydrocarbon chain residue having 1 to 7 carbon atoms; R1 and R2 each are hydrogen or an alkyl group, or R1 and R2 are combined with each other to form a 5- to 6-membered heterocyclic group optionally containing nitrogen; L and M each are hydrogen, or L and M are combined with each other to form a bond, or pharmaceutically acceptable salts thereof, having excellent hypoglycemic and hypolipidemic activities and are useful as anti-diabetics or hypolipidemic agents.
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(2008/06/13)

HETEROCYCLIC AMIDE DERIVATIVES AS TACHYKININ ANTAGONISTS
Compounds of formula (I), and salts and prodrugs thereof, wherein Q. sup.1 is phenyl substituted by one or more halo; optionally substituted naphthyl, indolyl, benzothiophenyl, benzofuranyl, benzyl or fluorenyl; the dotted line represents an optional covalent bond; one of X and Y is H and the other is hydroxy or C 1-6 alkoxy, or X and Y together form a group =O or =NOR 5 where R 5 is H or C. sub.1-6 alkyl; R. sup.1 is H or C 1-6 alkyl. R 2 is CO--W--R 6 where W represents a bond or a hydrocarbon chain of 1-6 carbon atoms and R 6 is an azacyclic or azabicyclic group; R 3 is H, C 1-6 alkyl or C. sub.2-6 alkenyl; and R 4 is phenyl optionally substituted by 1-3 of C. sub.1-6 alkyl, C. sub.2-6 alkenyl, C 2-6 alkynyl, halo, cyano, nitro, trifluoromethyl, trimethylsilyl, OR a, SR a, SOR. sup.a, NR a R b, NR a COR b, NR a CO 2 R b, CO 2 R a or CONR a R. sup.b, where R a and R b are H, C 1-6 alkyl, phenyl or trifluoromethyl; are tachykinin antagonists useful in therapy.
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(2008/06/13)

Pyridine derived agents for cardiovascular diseases
STR1 Compounds of formula (I) or a biolabile ester thereof, or a pharmaceutically acceptable salt of either, wherein Rl, R2, R3 and R4 are each independently selected from H or C1 -C4 alkyl; R5 is (CH2)m SO2 R6, (CH2)m NHSO2 R6 or (CH2)m NHCOR7 ; R6 and R7 are C1 -C6 alkyl, C1 -C3 perfluoroalkyl(CH2)n, C3 -C6 cycloalkyl(CH2)n, aryl(CH2)n or heteroaryl(CH2)n ; or R6 is NR8 R9 ; R8 is H or C1 -C4 alkyl; R9 is C1 -C6 alkyl, C3 -C6 cycloalkyl(CH2)n, aryl(CH2)n or heteroaryl(CH2)n ; or R8 and R9 together with the nitrogen atom to which they are attached form a 5- to 7-membered heterocyclic ring which may optionally incorporate a carbon-carbon double bond or a further hetero atom linkage selected from O, S, NH, N(C1 -C4 alkyl) and N(C1 -C5 alkanoyl), and which may optionally be substituted with one to three substituents each independently selected from C1 -C4 alkyl and C1 -C4 alkoxy, and which may optionally be benzo-fused; X is CH2, CHCH3, C(OH)CH3, C=CH2 or O; m is 0 or 1; n is 0, 1, 2 or 3; and Het is 3- or 4-pyridyl or 1-imidazolyl; with the proviso that when Het is 1-imidazolyl then X is CH2 or CHCH3, are combined thromboxane A2 synthetase inhibitors and thromboxane A2 /endoperoxide antagonists of utility in the treatment of disease conditions in which thromboxane A2 is a causative agent.
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(2008/06/13)

INSERTION OF CARBENES INTO P-H BONDS. 5. SYNTHESIS OF NEW PHOSPHONATES AND PHOSPHINATES IN REACTIONS CATALYSED BY Cu, Pd, Rh, Ni COMPLEXES
Cu(OTf)2 and Cu(acac)2 were found to be the most effective catalysts in the reaction of diazo compounds Ph2CN2 (1a), EtOC(O)CHN2 (1b), MeOC(O)CHN2 (1c), MeC(O)CN2C(O)OMe (1d), ClCH2C(O)CHN2 (1e) and CH2N2 (1f) with hydrophosphoryl compounds (MeO)2P(O)H (2a), (t-BuO)2P(O)H (2b), Ph(MeO)P(O)H (2c), (EtO)2P(O)H (2d) and P(O)H (2e) resulting in P-C bond formations.Cu, Pd and Rh acetates and Ni(acac)2 have a much lower efficiency.Chlorines in Cl3CC(O)CH2P(O)(OMe)2 (3k) and Cl2CHC(O)CH2P(O)(OMe)2 (3l) are reduced in the copper catalysed Atherton-Todd reaction.Key words: Catalyst; diazo compound; hydrophosphoryl compound; insertion; phosphonate; phosphinate.
Polozov, Alexander M.,Mustaphin, Albert H.,Khotinen, Alexander V.
p. 153 - 160
(2007/10/02)

REACTION CATALYZED BY TRIFLUOROMETHANESULFONIC ACID BETWEEN DIAZO COMPOUNDS AND DIALKYL HYDROGEN PHOSPHITES WITH THE FORMATION OF PHOSPHONATES
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Polozov, A. M.,Mustafin, A. Kh.
p. 1176
(2007/10/02)

Reaction of Diethyl Phosphorochloridite with Enolates: A General Method for Synthesis of β-Keto Phosphonates and α-Phosphono Esters through C-P Bond Formation
The reaction of ketone enolates with diethyl phosphorochloridite, followed by air oxidation of the intermediate reaction products, has proven to be a general and convenient method for preparation of β-keto phosphonates.Fourteen β-keto phosphonates have been prepared by this method, in an average yield greater than 60percent.This procedure also appears to be applicable to preparation of both α-phosphono aldehydes and α-phosphono esters.Although special precautions may be necessary to avoid aldol condensation during formation of aldehyde enolates, in two cases it was shown that the resulting enolates react readily with diethyl chlorophosphite.Finally, a set of five ethyl esters was converted to α-phosphono esters by this method.Yields of the α-phosphono esters are influenced by steric hindrance at the enolate carbon, but the average yield for this series was ca. 70percent.Because this synthetic method relies upon an electrophilic phosphorus reagent for formation of the C-P bond, it is complementary to the traditional Arbuzov synthesis.On the basis of the 21 examples presented here, it appears to be more widely applicable.
Lee, Koo,Wiemer, David F.
p. 5556 - 5560
(2007/10/02)

A new one-pot synthesis of dialkyl phosphonates from diazo compounds and dialkyl hydrogen phosphites
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Polozov,Polezhaeva,Mustaphin,Khotinen,Arbuzov
p. 515 - 517
(2007/10/02)

Carbanions phosphonate prepares par voie electrochimique: formation et reactivite vis-a-vis d'un aldehyde
Reactivity towards p-methoxybenzaldehyde (ArCHO) of electrochemically generated phosphonate carbanions has been investigated.Electrolyses were carried out at a mercury cathode in DMF and two routes to the desired carbanion have been compared: (i) Deprotonation of phosphonates of general formula (EtO)2P(O)CHYW (Y = W = Cl; Y = H, W = Cl; Y = Cl, W = CO2Et; Y = H, W = CO2Et; Y = CH3, W = CO2Et; Y = Cl, W = CH3), by the bases resulting from the electroreduction of azobenzene; addition of the carbanion formed onto the carbonyl group takes place and leads to the adduct (EtO)2P(O)CYW(Ar)O-. (ii) Two-electron reduction of halophosphonates (EtO)2P(O)CXYW (X = Cl, Y and W as above; X = Br, W = CO2Et, Y = Cl, Br, or CH3); when no H atom is present on the carbon bearing the phosphonate group (Y and W no = H), the same evolution leading to the above adduct is observed, on the contrary, when Y = H, the electrogenerated carbanion deprotonates the substrate and the resulting carbanion (EtO)2P(O)CXW reacts with the aldehyde; giving the adduct (EtO)2P(O)CXW(Ar)O-.Evolution of the intermediate adduct depends on the substituents Y (or X) and W: when W = CO2Et, whatever the nature of Y (or X), diethyl phosphate is eliminated with formation of the ethylenic ArCH=CWY (or X) (Wittig-Horner reaction); the same evolution is observed when Y = W = Cl.When W = Cl and Y = H or CH3, the final product is the phosphonate epoxyde resulting from chloride elimination (Darzens reaction).Chemo- and stereoselectivity depend only on the nature of Y and W but are independent of the mode of generation of the carbanion.Yields are limited by side-protonation reactions, which are related to the basicity of the phosphonate carbanions.Analysis of the results permits selection of the optimal electrolysis conditions for purposes of synthesis.Key words: electrosynthesis, electrogenerated bases, phosphonates, Wittig-Horner.
Le Menn, Jean-Christophe,Sarrazin, Jean,Tallec, Andre
p. 1332 - 1343
(2007/10/02)

Synthesis of indoles and L-tryptophans specifically 2H- or 13C-labelled in the six-membered ring
(4-2H)-, (5-2H)-, (6-2H)-, (7-2H)-, (4-13C)- and (5-13C)-1H-indole and the corresponding six L-tryptophans have been synthesized from simple labelled starting materials via a single reaction scheme.The L-tryptophans were prepared from the indoles via a quantitative one-step biosynthetic conversion.A scheme leading to the synthesis of three other indoles, mono-13C-enriched in the six-membered ring, has been developed and optimized.Indole and L-tryptophan, 13C- or 2H-enriched at the positions 4 or 5, have been synthesized with 99percent isotope incorporation without scrambling. (6-2H)-1H-Indole and -tryptophan have been synthesized with 95percent deuterium incorporation and (7-2H)-1H-indole and -tryptophan with 96percent.The reactions have been carried out on a gram scale and, in the case of the 4-13C system, they have been scaled up to the ten-gram level with no deterioration in yield.
Berg, Ellen M. M. van den,Liemt, Willem B. S. van,Heemskerk, Bram,Lugtenburg, Johan
p. 304 - 313
(2007/10/02)