- Synthesis and antiviral activity of C-3(C-28)-substituted 2,3-seco-triterpenoids
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Amide conjugates with four structural types of β-amino alcohols were synthesized from 2,3-seco-18αH-oleananoic and 2,3-seco-lupane C-3(C-28) mono- and dicarboxylic acids. Esters were prepared by reaction of C-3-hydroxy derivatives of A-seco-triterpenoids with dicarboxylic acid anhydrides. The antiviral activity of the synthesized compounds was studied against herpes simplex virus type I. The most active amide was 5a (5.7 μM, MTC/EC 50 32.2).
- Tolmacheva,Igosheva,Savinova,Boreko,Grishko
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- Synthesis of Cyclic Anhydrides via Ligand-Enabled C–H Carbonylation of Simple Aliphatic Acids
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The development of C(sp3)–H functionalizations of free carboxylic acids has provided a wide range of versatile C?C and C?Y (Y=heteroatom) bond-forming reactions. Additionally, C–H functionalizations have lent themselves to the one-step preparation of a number of valuable synthetic motifs that are often difficult to prepare through conventional methods. Herein, we report a β- or γ-C(sp3)–H carbonylation of free carboxylic acids using Mo(CO)6 as a convenient solid CO source and enabled by a bidentate ligand, leading to convenient syntheses of cyclic anhydrides. Among these, the succinic anhydride products are versatile stepping stones for the mono-selective introduction of various functional groups at the β position of the parent acids by decarboxylative functionalizations, thus providing a divergent strategy to synthesize a myriad of carboxylic acids inaccessible by previous β-C–H activation reactions. The enantioselective carbonylation of free cyclopropanecarboxylic acids has also been achieved using a chiral bidentate thioether ligand.
- Herron, Alastair N.,Yu, Jin-Quan,Zhuang, Zhe
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supporting information
p. 16382 - 16387
(2021/06/23)
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- Succinic anhydrides from epoxides
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Catalysts and methods for the double carbonylation of epoxides are disclosed. Each epoxide molecule reacts with two molecules of carbon monoxide to produce a succinic anhydride. The reaction is facilitated by catalysts combining a Lewis acidic species with a transition metal carbonyl complex. The double carbonylation is achieved in single process by using reaction conditions under which both carbonylation reactions occur without the necessity of isolating or purifying the product of the first carbonylation.
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Page/Page column 35
(2013/07/25)
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- PREPARATION OF PHARMACEUTICAL SALTS OF 3-O-(3',3'-DIMETHLSUCCINYL) BETULINIC ACID
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This invention relates to a novel process for making 3-O-(3',3'- dimethylsuccinyl)betulinic acid ("DSB")- This invention also relates to methods of treating HIV and related diseases using pharmaceutical compositions comprising salt forms of DSB prepared according to the process of the present invention. The invention further relates to dosage forms of pharmaceutical compositions comprising salts of DSB made using the process of this invention.
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Page/Page column 19
(2010/11/28)
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- Synthesis, nicotinic acetylcholine receptor binding, antinociceptive and seizure properties of methyllycaconitine analogs
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A series of methyllycaconitine (1a, MLA) analogs was synthesized where the (S)-2-methylsuccinimidobenzoyl group in MLA was replaced with a (R)-2-methyl, 2,2-dimethyl-, 2,3-dimethyl, 2-phenyl-, and 2-cyclohexylsuccinimidobenzoyl (1b-f) group. The analogs 1b-f were evaluated for their inhibition of [125I]iodo-MLA binding at rat brain α7 nicotinic acetylcholine receptors (nAChR). In order to determine selectivity, MLA and the analogs 1b-f were evaluated for inhibition of binding to rat brain α,β nAChR using [3H]epibatidine. At the α7 nAChR, MLA showed a Ki value of 0.87 nM, analogs 1b-e possessed Ki values of 1.67-2.16 nM, and 1f showed a Ki value of 26.8 nM. Surprisingly, the analog 1e containing the large phenyl substituent (Ki = 1.67 nM) possessed the highest affinity. None of the compounds possessed appreciable affinity for α,β nAChRs. MLA antagonized nicotine-induced seizures with an AD50 = 2 mg/kg. None of the MLA analogs were as potent as MLA in this assay. MLA and all of the MLA analogs, with the exception of 1b, antagonized nicotine's antinociceptive effects in the tail-flick assay. Compound 1c (Ki = 1.78 nM at α7 nAChR) with an AD50 value of 1.8 mg/kg was 6.7 times more potent than MLA (AD50 = 12 mg/kg) in antagonizing nicotine's antinociceptive effects but was 5-fold less potent than MLA in blocking nicotine-induced seizures. Since MLA has been reported to show neuroprotection against β-amyloid1-42, these new analogs which have high α7 nAChR affinity and good selectivity relative to α,β nAChRs will be useful biological tools for studying the effects of α7 nAChR antagonist and neuroprotection.
- Ivy Carroll,Ma, Wei,Navarro, Hernan A.,Abraham, Philip,Wolckenhauer, Scott A.,Damaj,Martin, Billy R.
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p. 678 - 685
(2007/10/03)
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- METHODS OF MANUFACTURING BIOACTIVE 3-ESTERS OF BETULINIC ALDEHYDE AND BETULINIC ACID
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The present invention provides a method for preparing a compound of formula (I), the method comprising contacting a compound of formula (II) with an effective amount of a compound of formula (III) or (IV). The present invention also provides a method for preparing a compound of formula (VI), the method comprising contacting a compound of formula (II) with an effective amount of one or more of 2,2-dimethylsuccinic acid, 2,2 dimethylbutanedioyl dichloride, 2,2-dimethylbutanedioyl dibromide, and 2,2 dimethylsuccinic anhydride. The present invention also provides a compound obtained from the method of the present invention.
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Page/Page column 26-27
(2008/06/13)
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- Highly efficient nickel-catalyzed cross-coupling of succinic and glutaric anhydrides with organozinc reagents
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A nickel-catalyzed alkylation of succinic and glutaric anhydrides with alkyl- and arylzinc reagents has been developed. A dramatic olefin effect has been investigated resulting in the identification of several styrene-based promoters which show pronounced enhancements in reaction rate. The substrate scope with respect to electrophilic and nucleophilic coupling partners has been examined and found to be remarkably broad, allowing for rapid introduction of molecular complexity through the use of functionalized coupling partners. Regioselective alkylation of an unsymmetrical succinic anhydride and a profound effect of pendent coordinating olefins on reaction rate suggest a mechanism involving discrete oxidative addition of the nickel complex into the cyclic anhydride followed by a transmetalation event.
- Bercot, Eric A.,Rovis, Tomislav
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p. 247 - 254
(2007/10/03)
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- Estrogen receptor ligands. Part 9: Dihydrobenzoxathiin SERAMs with alkyl substituted pyrrolidine side chains and linkers
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A series of benzoxathiin SERAMs was prepared. Minor modifications in the side chain or linker resulted in significant effects on biological activity, especially in uterine tissue. A series of dihydrobenzoxathiin SERAMs with alkylated pyrrolidine side chains or alkylated linkers was prepared. Minor modifications in the side chain or linker resulted in significant effects on biological activity, especially in uterine tissue.
- Blizzard, Timothy A.,Dininno, Frank,Morgan II, Jerry D.,Chen, Helen Y.,Wu, Jane Y.,Kim, Seongkon,Chan, Wanda,Birzin, Elizabeth T.,Yang, Yi Tien,Pai, Lee-Yuh,Fitzgerald, Paula M.D.,Sharma, Nandini,Li, Ying,Zhang, Zhoupeng,Hayes, Edward C.,Dasilva, Carolyn A.,Tang, Wei,Rohrer, Susan P.,Schaeffer, James M.,Hammond, Milton L.
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p. 107 - 113
(2007/10/03)
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- Process for producing optically active hemiesters
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There is disclosed a process for producing an optically active hemiester of formula (1): 1wherein R1, R2 and R5 represent the same meanings as described below, which comprises reacting a cyclic acid anhydride of formula (2): 2wherein R1 and R2 are different and independently represent a hydrogen atom, a halogen atom, an alkyl group optionally substituted with an alkoxy group or a halogen atom, and the like, with a hydroxy compound of formula (3): R3OH ??(3) wherein R3 represents an alkyl group optionally substituted with an alkoxy group, a phenoxy group, a dialkylamino group or a halogen atom and the like, in the presence of an asymmetric catalyst.
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- "ONE-POT" SYNTHESIS OF DISYMMETRICALLY α,α'-DISUBSTITUTED SUCCINIC ANHYDRIDES PRECURSORS
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A "one-pot" synthesis for disymmetrically α,α'-disubstituted succinic anhydrides precursors isreported in the present paper.Substituents are aryl, primary or secondary alkyl groups.This reaction represents a simple and quick method with fair yields.
- Dana, A.,Campagnole, M.,Bourgeois, M.J.,Montaudon, E.
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p. 2981 - 2988
(2007/10/03)
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- Synthesis of Chiral Cobalt Complexes with Planoid-Tetradentate Ligand System
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The synthesis of a series of Cbl-related, achiral Co(III) complexes 9a-c as well as enantiomerically pure, C2-symmetric Co(III) complexes 15 and 18, is reported (Schemes 3, 5, and 7).The crystal structures of 9c and 15 were determined.Complex 18 acts as an enantioselective catalyst in the isomerization of 1,4-epiperoxides to hydroxycycloalkenones.
- Haerter, Ralph,Weymuth, Christophe,Scheffold, Rolf,Engel, Peter,Linden, Anthony
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p. 353 - 371
(2007/10/02)
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- Ashless additives for lubricating compositions
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Superior ashless additives for lubricants are prepared by a process comprising first introducing a petroleum sulfonic acid and a polyamine to a reaction zone and subsequently introducing a cyclic anhydride of a dicarboxylic acid into the reaction zone. In another embodiment, the solids content of the additives is reduced to acceptable levels by removal of free SO2 from the petroleum sulfonic acid prior to preparing the additive. Lubricating oil compositions containing these ashless additives are also provided.
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