- A Diels-Alder reaction for the total synthesis of the novel antibiotic antitumor agent mensacarcin
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The antibiotic mensacarcin (1), which contains nine stereogenic centers and two epoxy functionalities, is a novel antitumor agent that was first isolated from the culture broth of Streptomyces sp. Goe C4/4 found in a soil sample next to the northern cafeteria of the University of Goettingen. For the synthesis of 1 and related structurally simplified analogs, a Diels-Alder reaction of O-methyljuglone (11) and the tetra-substituted 1,3-butadiene 22 was performed to give the cycloadduct rac-28, which was transformed into the epoxides rac-31 and rac-33. The cytotoxicity of rac-33 is only 53 times lower than the much more complex 1. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
- Tietze, Lutz F.,Guentner, Carlos,Gericke, Kersten M.,Schuberth, Ingrid,Bunkoczi, Gabor
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Read Online
- Chain hydrocarbon substituted isoindoline -1, 3 - diketone PDE4 inhibitor and medicinal use thereof
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The invention relates to a compound shown I and a racemate thereof. A stereoisomer, a tautomer, an isotope label, a solvate, a polymorph, an ester, a prodrug or a pharmaceutically acceptable salt thereof, and a preparation method thereof, and a medical use thereof, the structure of said formula I being as follows.
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Paragraph 0259-0262
(2021/10/27)
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- Preparation method and application of iopromide intermediate (by machine translation)
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The invention relates to a preparation method of an iopromide intermediate and an application thereof in preparation of iopromide. The method comprises the following steps: compound VI compound is subjected to reduction reaction under the action of Raney nickel/hydrazine hydrate to obtain the compound V compound. The reaction is carried out under normal pressure, the operation is simple and safe, the generated intermediate impurities are less, and the reaction is more suitable for industrial production. The method is used for preparing iopromide, can avoid the generation of a diacylated by-product, can effectively reduce the generation of by-products in the preparation process, can be easily separated and purified, and can obtain high-purity iopromide with high yield. (by machine translation)
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Paragraph 0056-0058
(2020/07/24)
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- Synthesis and application of peptide borate compounds
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The invention belongs to the field of drug synthesis, and specifically relates to a series of novel peptide borate compounds or pharmaceutical salts thereof, and a preparation method and pharmaceutical application thereof. The structure of the peptide borate compounds or the pharmaceutical salts thereof is as shown in a formula I which is described in the specification. The compounds of the invention can be used for preparing proteasome inhibitors, and thus can be further used for treating solid tumors and blood tumors.
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Paragraph 0163; 0179-0181
(2019/12/25)
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- Synthesis method of optically active metalaxyl
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The invention discloses a synthesis method of optically active metalaxyl. The optically active metalaxyl is synthesized by performing methoxylation and acylating chlorination on chloroacetic acid to obtain methoxyacetyl chloride and then reacting Methoxyacetyl chloride with D-N-(2,6-dimethylphenyl) alanine methyl ester; a one-pot method operation is adopted for the synthesis; the two-step reactionof methoxylation and acylating chlorination is directly used for a next-step reaction without post-treatment. According to the process of the optically active metalaxyl, by adopting the one-pot method operation, the operation steps are simplified, the production of three wastes is decreased, the synthesis cost is reduced, the obtained product is stable in quality and relatively high in output andyield, and the synthesis method is suitable for large-scale production.
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Paragraph 0031-0035; 0041-0045; 0051-0055; 0061-0065; 0071
(2019/01/21)
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- Optimization of 2-alkoxyacetates as acylating agent for enzymatic kinetic resolution of chiral amines
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In this study, the activity of acetic acid esters modified with electron withdrawing 2-alkoxy-groups was investigated as acylating agent in kinetic resolution (KR) of racemic amines. A homologous series of the isopropyl esters of four 2-alkoxyacetic acids (2-methoxy-, 2-ethoxy-, 2-propoxy- and 2-butoxyacetic acids) were prepared and investigated for enantiomer selective N-acylation, catalyzed by lipase B from Candida antarctica, under batch and continuous-flow conditions. In the first set of experiments, isopropyl 2-propoxyacetate showed the highest effectivity with all of the four racemic amines [(±)-1-phenylethylamine, (±)-4-phenylbutan-2-amine, (±)-heptan-2-amine and (±)-1-methoxypropane-2-amine] in the set enabling excellent conversions (≥46%) and enantiomeric excess values (ee ≥ 99%) with each amines in continuous-flow mode KRs under the optimized reaction conditions. In a second set of experiments, KRs of five additional amines – being substituted derivatives of (±)-1-phenylethylamine – further demonstrated the usefulness of isopropyl 2-propoxyacetate – being the best acylating agent in the first set of KRs – in KRs leading to (R)-N-propoxyacetamides with high ee values (≥99.8%).
- Oláh, Márk,Kovács, Dániel,Katona, Gabriel,Hornyánszky, Gábor,Poppe, László
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supporting information
p. 3663 - 3670
(2018/06/04)
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- Preparation methods of iopromide and intermediate of iopromide
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The application of the invention relates to preparation methods of iopromide and an intermediate of the iopromide. The method specifically comprises the following steps: conducting a reduction reaction, an iodination reaction and an acylation reaction on a compound shown in the formula VI to prepare a compound shown in the formula III, and further preparing to obtain the iopromide. The method notonly avoids the generation of double acylation byproducts, but also effectively reduces the generation of byproducts in the preparation process, the intermediate is easy to separate and purify, and ahigh-purity product is obtained at a relatively high yield.
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Paragraph 0055-0057
(2018/03/24)
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- Primary, Secondary, and Tertiary γ-C(sp3)-H Vinylation of Amides via Organic Photoredox-Catalyzed Hydrogen Atom Transfer
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An efficient strategy for primary, secondary and tertiary aliphatic γ-C(sp3)-H vinylation of amides with alkenylboronic acids is reported. These reactions are catalyzed by visible-light organic photoredox agents. Regioselective γ-C(sp3)-H vinylation of amides is controlled by a 1,5-hydrogen atom transfer of an amidyl radical generated in situ.
- Chen, Hui,Guo, Liangliang,Yu, Shouyun
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supporting information
p. 6255 - 6259
(2018/10/05)
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- Terpene Cyclizations inside a Supramolecular Catalyst: Leaving-Group-Controlled Product Selectivity and Mechanistic Studies
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The tail-to-head terpene cyclization is arguably one of the most complex reactions found in nature. The hydrogen-bond-based resorcinarene capsule represents the first man-made enzyme-like catalyst that is capable of catalyzing this reaction. Based on noncovalent interactions between the capsule and the substrate, the product selectivity can be tuned by using different leaving groups. A detailed mechanistic investigation was performed to elucidate the reaction mechanism. For the cyclization of geranyl acetate, it was found that the cleavage of the leaving group is the rate-determining step. Furthermore, the studies revealed that trace amounts of acid are required as cocatalyst. A series of control experiments demonstrate that a synergistic interplay between the supramolecular capsule and the acid traces is required for catalytic activity.
- Zhang, Qi,Catti, Lorenzo,Pleiss, Jürgen,Tiefenbacher, Konrad
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supporting information
p. 11482 - 11492
(2017/08/30)
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- RECYCLABLE CATALYSTS FOR CHLORINATION OF ORGANIC ACIDS AND ALCOHOLS
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The present invention discloses recyclable polymeric catalyst of Formula I, for chlorination of organic acids and alcohols using chlorinating agents such as carbonyl chloride, oxalyl chloride or thionyl chloride, wherein, ‘m’ on the pendent groups on polystyrene backbone can have values from 1 to 5 and R is the alkyl group ranging from C1 to C5.
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Paragraph 0103
(2017/10/10)
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- A mild method for the replacement of a hydroxyl group by halogen. 1. Scope and chemoselectivity
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α-Chloro-, bromo- and iodoenamines, which are readily prepared from the corresponding isobutyramides have been found to be excellent reagents for the transformation of a wide variety of alcohols or carboxylic acids into the corresponding halides. Yields are high and conditions are very mild thus allowing for the presence of sensitive functional groups. The reagents can be easily tuned allowing therefore the selective monohalogenation of polyhydroxylated molecules. The scope and chemoselectivity of the reactions have been studied and reaction mechanisms have been proposed.
- Munyemana, Fran?ois,George, Isabelle,Devos, Alain,Colens, Alain,Badarau, Eduard,Frisque-Hesbain, Anne-Marie,Loudet, Aurore,Differding, Edmond,Damien, Jean-Marie,Rémion, Jeanine,Van Uytbergen, Jacqueline,Ghosez, Léon
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p. 420 - 430
(2015/12/31)
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- Copper(II)-Catalyzed [4+1] annulation of propargylamines with N,O-acetals: Entry to the synthesis of polysubstituted pyrrole derivatives
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Described herein is the CuCl2-catalyzed [4+1] annulation of a variety of propargylamines with N,O-acetals that function as a C1 unit, leading to the production of polysubstituted pyrrole derivatives. Three important features of the N,O-acetal during the [4+1] annulation series via 5-endo-dig cyclization are described: an enolizable substituent adjacent to the central sp3-carbon is required, the central sp3-carbon displays the functions of both an electrophile and a nucleophile, and liberation of the secondary amine smoothly leads to the aromatization. A CuCl2-catalyzed [4+1] annulation of propargylamines with N,O-acetals having an ester, a ketone, and an amide moiety, leading to the facile preparation of polysubstituted pyrrole derivatives is presented. This annulation series was achieved through 5-endo-dig cyclization and subsequent aromatization in one pot.
- Sakai, Norio,Hori, Hiroaki,Ogiwara, Yohei
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supporting information
p. 1905 - 1909
(2015/03/18)
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- A METHOD FOR PREPARING AN INTERMEDIATE OF IOPROMIDE
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The present invention relates to a method for preparing an intermediate of iopromide, and more particularly, to a method for preparing an intermediate of iopromide, in which 5-methoxyacetylamino-2,4,6-triiodoisophthalic acid dichloride is produced using 1,4-dioxane as a reaction solvent, and then reacted with 3-amino-1,2-propanediol using a solvent mixture of 1,4-dioxane or tetrahydrofuran (THF) and isopropanol as a reaction solvent to obtain the intermediate of iopromide with a faster reaction time, a smaller amount of solvent, and a higher yield.
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Paragraph 113-116
(2015/05/06)
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- Synthesis and biological evaluation of paleo-soraphens
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Synthesis can provide molecules such as paleo-soraphens A and B (see scheme) that are genetically encoded but not obtained from the natural source. Although it is unclear whether this is part of an evolutionary process or the consequence of the chemical synthesis, the biological evaluation of these genetically encoded natural products can shed light on how natural products are structurally optimized with respect to their biological profile. Copyright
- Lu, Hai-Hua,Raja, Aruna,Franke, Raimo,Landsberg, Dirk,Sasse, Florenz,Kalesse, Markus
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supporting information
p. 13549 - 13552
(2014/01/06)
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- Trimethylsilyl trifluoromethanesulfonate-promoted cyclocondensation of β-ketoenamides and subsequent nonaflation to pyrid-2-yl and pyrid-4-yl nonaflates as flexible precursors for polysubstituted pyridines
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The intramolecular condensation of β-ketoenamides to 2- and/or 4-pyridone derivatives using either KOt-Bu or trimethylsilyl trifluoromethanesulfonate/Hu?nig's base was investigated. Subsequent nonaflation of the cyclization products allowed a facile purification and further functionalization through Suzuki-Miyaura couplings leading to new highly substituted pyridine derivatives. The dependence of the regioselectivity of cyclocondensation on the structure of the β-ketoenamides is discussed. Georg Thieme Verlag Stuttgart New York.
- Hommes, Paul,Berlin, Sarah,Reissig, Hans-Ulrich
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supporting information
p. 3288 - 3294
(2013/12/04)
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- Asymmetric hydrogenation of α- Or β-acyloxy α,β- unsaturated phosphonates catalyzed by a Rh(i) complex of monodentate phosphoramidite
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The Rh(i) complex of a monodentate phosphoramidite bearing a primary amine moiety (DpenPhos) has been disclosed to be highly efficient for the asymmetric hydrogenation of a variety of α- or β-acyloxy α,β- unsaturated phosphonates, providing the corresponding biologically important chiral α- or β-hydroxy phosphonic acid derivatives with excellent enantioselectivities (90->99% ee).
- Zhang, Jinzhu,Dong, Kaiwu,Wang, Zheng,Ding, Kuiling
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supporting information; scheme or table
p. 1598 - 1601
(2012/03/22)
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- Uncharacterized 4,5-dihydroxy-2,3-pentanedione (DPD) molecules revealed through NMR spectroscopy: Implications for a greater signaling diversity in bacterial species
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Talking bacteria: The combination of NMR spectroscopy and 4,5-dihydroxy-2,3-pentanedione (DPD) homologue analysis reveals that DPD, a bacterial signaling compound in the autoinducer-2 (AI-2) class (see scheme), exists as a much more complex structural array of molecules than previously appreciated. This finding suggests the existence of a larger bacterial chemical signaling language than previously thought. Copyright
- Globisch, Daniel,Lowery, Colin A.,McCague, Karen C.,Janda, Kim D.
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supporting information; experimental part
p. 4204 - 4208
(2012/05/20)
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- 4,4-Bis(methylthio)azetidin-2-ones as synthons of 1,2- and 1,3-dicarbonyl systems
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The importance of β-lactams as synthetic building blocks has been widely recognized in organic synthesis due to possible ring cleavage at any of the four single bonds of the β-lactam ring. We now report reactions involving breaking of the N1-C4 bond in differently substituted at C3 4,4-bis(methylthio)azetidin-2-ones, leading to formation of 1,2- and 1,3-dicarbonyl systems.
- Konaklieva, Monika I.,Suwandi, Lita S.,Kostova, Maya,Deschamps, Jeffrey
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supporting information; experimental part
p. 1909 - 1912
(2011/04/25)
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- Conformational preferences for some 2-substituted N-methoxy-N- methylacetamides through spectroscopic and theoretical studies
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The analysis of the IR carbonyl band of the 2-substituted N-methoxy-N-methylacetamides Y-CH2C(O)N(OMe)Me (Y = F 1, OMe 2, OPh 3, Cl 4), supported by B3LYP/6-311++G(3df, 3pd) calculations along with the NBO analysis for 1-4, indicated the existence of cis-gauche conformers i.e. (c) and (g) for 1 and 3, (c1, c2) and (g1, g 2) for 2, and (c) and (g1, g2) for 4. In the gas phase, the g conformer population prevails over the c one, for 1 and 3, the (c1 + c2) population prevails over the (g1 + g2) one for 2, and the (g1 + g2) conformer population is more abundant than (c) one for 4. In n-hexane solution, the cis conformer is more abundant for 1-3. The occurrence of Fermi resonance in the νCO region, in n-hexane, precludes the estimative of relative populations of the (c, g1, g2) conformers for 4. The SCI-PCM calculations agree with the solvent effect on the νCO band component relative intensities for 1-3. NBO analysis showed that the n N → πco* orbital interaction is the main factor which stabilizes the gauche (g, g1, g2) conformers for 1-4 into a larger extent relative to the cis (c, c1, c2) ones. The nY → πco *, σC-Y → πco*, πco → σC-Y* and πco* → σC-Y* orbital interactions still contribute, but into a minor extent for the stabilization of the gauche conformers relative to the cis ones. The existence of some pyramidalization at the nitrogen atom of the Weinreb amides 1-4 is responsible for the occurrence of Yδ-(4)?Oδ-(9) and Y δ-(4)?Nδ-(7) short contacts in the gauche (g, g1, g2) conformers, which originates strong repulsive Coulombic interactions, acting in opposition to the large orbital stabilization of the gauche conformer with respect to the cis one. Therefore, a delicate balance of the Coulombic and orbital interactions seems to be responsible for the observed stabilization of the gauche (g, g1, g2) and cis (c, c1, c2) conformers, both in the gas phase and in the solution for 1-4. However, the cis conformer predominance, in non polar solvents, for the 2-substituted N-methoxy-N-methyl acetamides 1-3, bearing in α first raw (fluorine and oxygen) atoms, is in the opposite direction to the gauche conformer preference for the corresponding 2-substituted N,N-dialkyl-acetamides.
- Olivato, Paulo R.,Da Silva Gomes, Roberto,Rodrigues, Alessandro,Reis, Adriana K.C.A.,Domingues, Nelson L.C.,Rittner, Roberto,Dal Colle, Maurizio
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experimental part
p. 106 - 116
(2010/10/04)
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- Quantification of CH...π interactions: Implications on how substituent effects influence aromatic interactions
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Attractive interactions between a substituted benzene ring and an α-substituted acetate group were determined experimentally by using the triptycene model system. The attractive interaction correlates well with the Hammett constants σm (R2=0.90), but correlates much better with the acidity of the α-protons (R2=0.98). A predominant CH...π interaction was found to control the conformational preference of model compounds 1a-g. Despite the predominance of the CH...π interaction in compounds 1a-g, a Hammett plot displays a fairly straight line for the substituent effect. These results show that when using Hammett plots in a simplified model system, a system designed to study the effect of X...π interactions could capture the X-H...π interaction instead.
- Gung, Benjamin W.,Emenike, Bright U.,Lewis, Michael,Kirschbaum, Kristin
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supporting information; experimental part
p. 12357 - 12362
(2010/12/25)
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- Kinase inhibitor compounds
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The invention relates to compounds, compositions comprising the compounds, and methods of using the compounds and compound compositions. The compounds, compositions, and methods described herein can be used for the therapeutic modulation of kinase-mediated processes, and treatment of disease and disease symptoms, particularly those mediated by certain kinase enzymes.
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Page/Page column 36
(2009/04/24)
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- KINASE INHIBITOR COMPOUNDS
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The invention relates to compounds, compositions comprising the compounds, and methods of using the compounds and compound compositions. The compounds, compositions, and methods described herein can be used for the therapeutic modulation of kinase-mediated processes, and treatment of disease and disease symptoms, particularly those mediated by certain kinase enzymes.
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Page/Page column 74
(2008/06/13)
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- Fast DKR of amines using isopropyl 2-methoxyacetate as acyl donor
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The dynamic kinetic resolution (DKR) of various primary amine substrates was performed using a modified version of the Baeckvall system. A single equivalent of isopropyl 2-methoxyacetate was used as acyl donor in combination with p-MeO Shvo complex as the racemization catalyst and Novozym 435 as the acylation catalyst. A reaction temperature of 100°C was employed to ensure a high racemization rate. Adding 2,4-dimethyl-3-pentanol (DMP) as hydrogen donor at a concentration of 0.5 M successfully suppressed side product formation. Under these modified DKR conditions, complete conversion was observed for most substrates within 26 h showing both high ee values and good chemoselectivity, whereas the original system required a reaction time of 72 h. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
- Veld, Martijn A. J.,Hult, Karl,Palmans, Anja R. A.,Meijer
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p. 5416 - 5421
(2008/03/18)
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- Gonadotropin releasing hormone receptor antagonists
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The present invention relates to Gonadotropin Releasing Hormone (“GnRH”) (also known as Leutinizing Hormone Releasing Hormone) receptor antagonists.
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Page/Page column 23
(2010/02/15)
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- SUBSTITUTED CYCLOHEXYL-1,4-DIAMINE DERIVATIVES WITH A CHAIN EXTENSION
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The invention relates to substituted cyclohexyl-1,4-diamine derivatives, to a method for their production, to medicaments containing said compounds and to the use of substituted cyclohexyl-1,4-diamine derivatives for producing medicaments.
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Page/Page column 25
(2008/06/13)
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- Polycyclic compounds from aminopolyols and a-dicarbonyls: Structure and application in the synthesis of exoditopic ligands
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The structure and stereochemistry of the crystalline 2 : 2 condensation product ("glytham") of glyoxal and tris(hydroxymethyl)aminomethane was conclusively determined by X-ray diffractometric analysis. The singular disposition of the heteroatoms suggests the employment of glytham as starting material for the synthesis of ditopic ligands for metal ions. Some derivatives of glytham were prepared and their binding properties towards alkaline metal ions were preliminarily investigated by ESI-MS and NMR. The Royal Society of Chemistry 2005.
- Giovenzana, Giovanni B.,Palmisano, Giovanni,Del Grosso, Erika,Giovannelli, Lorella,Penoni, Andrea,Pilati, Tullio
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p. 1489 - 1494
(2007/10/03)
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- SUBSTITUTED ACETANILIDES AND BENZAMIDES FOR THE TREATMENT OF ASTHMA AND PULMONARY INFLAMMATION
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Substituted acetanilide or benzamide compositions or formulations for delivery by aerosolization are described. The formulation contains an efficacious amount of acetanilide or benzamide compound able to inhibit inflammation in asthmatic lungs. Compounds of the invention are formulated in 5 ml solution of a quarter normal saline having pH between 5.0 and 7.0. The method for treatment of respiratory tract inflammation by a formulation delivered as an aerosol having mass medium average diameter predominantly between 1 to 5 μ, produced by nebulization or dry powder inhaler.
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Page/Page column 24
(2008/06/13)
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- The synthesis of tetrahydroquinolines related to Virantmycin
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4-Substituted anilines react with 1-methoxymethyl-1-butyl-3- trimethysilylpropargyl chloride but not with 1,1-dibutyl-3- trimethylsilylpropargyl chloride, to form the corresponding substituted N-propargylanilines. These anilines cyclise, using cuprous chloride, in the presence of trifluoroacetic anhydride, and, when the aniline substituent is electron donating, to give 6-substituted 2-butyl-2-methoxymethyl-1- trifluoroacetyl-1,2-dihydroquinolines. Chlorination, followed by selective dechlorination using sodium cyanoborohydride, of the 6-methyl product yields 2-butyl-2-methoxymethyl-3-chloro-6-methyl-1-trifluoroacetyl-1,2,3, 4-tetrahydroquinoline which has the same relative stereochemistry as that in the antiviral compound, Virantmycin.
- Francis, Craig L.,Williamson, Natalie M.,Ward, A. David
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p. 2685 - 2691
(2007/10/03)
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- THIADIAZOLEDIOXIDES AND THIADIAZOLEOXIDES AS CXC- AND CC-CHEMOKINE RECEPTOR LIGANDS
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Disclosed are novel compounds of the formula (IA) and the pharmaceutically acceptable salts and solvates thereof. Examples of groups comprising Substituent A include heteroaryl, aryl, heterocycloalkyl, cycloalkyl, aryl, alkynyl, alkenyl, aminoalkyl, alkyl or amino. Examples of groups comprising Substituent B include aryl and heteroaryl. Also disclosed is a method of treating a chemokine mediated diseases, such as, cancer, angiogenisis, angiogenic ocular diseases, pulmonary diseases, multiple sclerosis, rheumatoid arthritis, osteoarthritis, stroke and cardiac reperfusion injury, acute pain, acute and chronic inflammatory pain, and neuropathic pain using a compound of formula (IA).
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Page 315-316
(2008/06/13)
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- 13-substituted milbemycin derivatives, their preparation and their use against insects and other pests
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Compounds of formula (I) and salts thereof: Wherein R1 represents methyl, ethyl, isopropyl or s-butyl; and R2 represents hydrogen or alkyl. R3 represents hydrogen, optionally substituted alkanoyl, optionally substituted alkenoyl, optionally substituted alkynoyl, alkylsulfonyl, or alkoxycarbonyl, or R2 and R3 together with the nitrogen atom to which they are attached form a saturated, optionally substituted 4- to 6-membered heterocyclic ring group. The moiety -a- together with the carbon atom to which it is attached forms a 3- to 6-membered cycloalkyl group. These compounds have anthelmintic, acaricidal and insecticidal activity.
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- Application of the Suzuki reaction as the key step in the synthesis of a novel atropisomeric biphenyl derivative for use as a liquid crystal dopant
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A heavily functionalized atropisomeric biphenyl derivative (4), which is designed to possess a large lateral dipole moment, has been synthesized with use of a Suzuki coupling as the key step and resolved by chiral HPLC. The final coupling reaction is complicated by rapid hydrolytic deboronation of the sterically hindered, electron poor boronate 22. Rigorously anhydrous conditions are therefore necessary to achieve the coupling.
- Cammidge, Andrew N.,Crepy, Karen V. L.
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p. 6832 - 6835
(2007/10/03)
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- Anti-selective aldol reactions with titanium enolates of N-glycolyloxazolidinethiones
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(Matrix presented). A highly diastereoselective anti aldol addition utilizing a variety of N-glycolyloxazolidinethiones has been developed. Enolization of an N-glycolyloxazolidinethione with titanium (IV) chloride and (-)-sparteine followed by addition of an aldehyde activated with additional TiCl4 resulted in highly anti-selective aldol additions, typically with no observable syn isomers. Allyl-protected glycolates demonstrated the highest levels of selection and yields, although O-benzyl and O-methyl glycolyloxazolidinethiones also performed well.
- Crimmins, Michael T.,McDougall, Patrick J.
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p. 591 - 594
(2007/10/03)
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- Synthesis of azetidin-2-one via in situ generated acid chlorides using hexachloroacetone-triethylphosphite
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A one step synthesis of azitidine-2-ones 3a-i has been described by the reaction of imines 2 with acids 1 in the presence of hexachloroacetone, triethylphosphite and triethylamine.
- Arun,Govande,Deshmukh,Bhawal
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p. 856 - 857
(2007/10/03)
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- Benzothiazole derivatives with activity as adenosine receptor ligands
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The present invention relates to substituted benzothiazole derivitives and to their pharmaceutically acceptable salts useful for the treatment of diseases related to the adenosine receptor.
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- Chain carbonylation of methoxymethyl chloride by using AgSbF6 catalyst under high pressure of CO
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The chain carbonylation of methoxymethyl chloride (1) by the use of AgSbF6 catalyst smoothly proceeded under high pressure of carbon monoxide to give methyl methoxyacetate after treatment with methanol. The reaction was highly dependent on the CO pressure and the reaction temperature, indicating the presence of equilibrium processes. From the temperature dependence of the equilibrium constant, the enthalpy change of the reaction was calculated to be -25.4 kJ mol-1.
- Ohga, Yasushi,Netsu, Fuminori,Mori, Sadayuki,Kudo, Kiyoshi,Komatsu, Koichi,Sugita, Nobuyuki
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p. 11119 - 11124
(2007/10/02)
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- SULFURIC ACID CATALYZED DECARBONYLATION OF ALKOXYACETYL CHLORIDES
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Sulfuric acid catalyzes the decarbonylation of alkoxyacetyl chlorides to produce the corresponding chloromethyl alkyl ethers in fairly good yields.
- Basavaiah, D.,Rao, P. Dharma,Gowriswari, V. V. L.
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p. 1411 - 1414
(2007/10/02)
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- Esters of alkoxy-acylderivatives of carnitine and pharmaceutical compositions containing same
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A novel class of esters of alkoxy-acylderivatives of carnitine, wherein the alkoxy-acyl radical has from 3 to 6 carbon atoms (typically: methoxyacetyl, methoxypropionyl, ethoxyacetyl, ethoxypropionyl and propoxyacetyl) is prepared by esterifying carnitine and then acylating the carnitine ester. Such esters are therapeutically useful in the treatment of cardiac disorders, hyperlipidaemias and hyperlipoproteinaemias.
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- CONFIGURATIONAL BIASING OF TERTIARY AMIDE IONOPHORES BY ALKALI METAL CHELATION1,2.
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Configurational analysis can be used as a probe for association constants for chelation of amides with alkali metals. Carbon-13 NMR spectroscopy indicates that tertiary amides, each bearing a triethylene oxide substituent at nitrogen, exist as a mixture of E and Z isomers. Addition of alkali metal cation (KSCN) increases the concentration of species with the Z configuration since this configuration can chelate potassium ion. High-field **1H NMR spectra have been used to determine the chelation constants for amides in the presence of KSCN. It has been determined that (a) the carbonyl oxygen is involved in chelation and (b) the number of ether oxygens on the substituent at nitrogen is the significant factor in the chelating ability of these ionophores.
- Craine,Greenblatt,Woodson,Hortelano,Raban
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p. 7252 - 7255
(2007/10/02)
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- Process for preparing amides by reaction in presence of molecular sieve
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There is provided a process for preparing amides which comprises reacting an amine, or an amide, and an acid halide, or anhydride, in suitable molecular proportions, in an inert organic diluent, in the presence of an effective amount of a molecular sieve, until the reaction is completed, separating the molecular sieve, and recovering the amide from the organic mother liquor.
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- Mechanism of Hydrolysis of N-(1-Aminoalkyl) Amides
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Many of the title compounds (structure 1) are remarkably stable to hydrolysis and can be isolated and characterized.The pH-rate profile for hydrolysis of the title compounds involves plateaus in the acid and base region, with the rate of hydrolysis in the basic region somewhat faster.The compounds hydrolyze to amides, aldehydes, and ammonia; the intermediacy of an imine in the basic region is demonstrated by its trapping with added CN-.An optically active derivative of 1 hydrolyzes and loses optical activity at about the same rate in both the acidic and basic regions of pH.The reaction is characterized in basic solution by highly positive activation entropies, and alkylation of the amino nitrogen increases the rate significantly.The hydrolysis reaction shows no detectable buffer catalysis at any pH studied.The hydrolysis reaction is very sensitive to the amide leaving group; electron-withdrawing substituents on the amide portion of 1 substantially increase the rate of hydrolysis.The mechanism of hydrolysis in basic solution seems to be best described as a unimolecular solvolysis with an amide anion as a leaving group (Scheme I).In acidic solution the most likely mechanism of hydrolysis (Scheme II) appears to involve the expulsion of an amide enol (imidic acid).The implications of these findings are discussed for situation in which compounds of type 1 have found utility.
- Loudon, G. Marc,Almond, Merrick R.,Jacob, James N.
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p. 4508 - 4515
(2007/10/02)
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- Substituted 2,4,6-triiodoisophthalamic acids
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Certain N-[poly(hydroxyalkyl)alkyl], 2,4,6-triiodoisophthalamic acids are useful as x-ray contrast agents. A representative compound has the structure STR1
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- 2-Acyl-3-substituted cyclopentan-1-ones and process for their preparation
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1,3-Dicarbonyl compounds useful as medicines, agricultural chemicals, perfumes, and their intermediates are prepared by reacting a specific α,β-unsaturated carbonyl compound with a specific organic copper lithium compound in the presence of an aprotic inert organic solvent, and then reacting the reaction product with an organic carboxylic acid halide or anhydride. In particular, novel 2-acyl-3-substituted cyclopentan-1-ones and 2-acyl-3-substituted cyclohexan-1-ones having important physiological activities are provided.
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