- Preparation method of alpha-hydroxyl-gamma-butyrolactone
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The invention belongs to the field of preparation of organic compounds, and provides a preparation method of alpha-hydroxyl-gamma-butyrolactone. The method is characterized in that malic acid is used as a raw material, and alpha-hydroxyl-gamma-butyrolactone is synthesized with high yield through four steps of reactions, namely, carboxyl and alpha-hydroxyl protection, beta-carboxyl reduction, protecting group removal and internal esterification. The method has the advantages of easily available raw materials, mild reaction conditions and low cost, and is suitable for large-scale preparation of alpha-hydroxy-gamma-butyrolactone.
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Paragraph 0024; 0026
(2021/06/13)
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- CYCLIC PHOSPHATE SUBSTITUTED NUCLEOSIDE DERIVATIVES AND METHODS OF USE THEREOF FOR THE TREATMENT OF VIRAL DISEASES
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The present invention relates to Cyclic Phosphate Substituted Nucleoside Derivatives of Formula (I), and pharmaceutically acceptable salts thereof, wherein A, B, Q, V, R1, R2 and R3 are as defined herein. The present invention also relates to compositions comprising a Cyclic Phosphate Substituted Nucleoside Derivative, and methods of using the Cyclic Phosphate Substituted Nucleoside Derivatives for treating or preventing HCV infection in a patient.
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Page/Page column 47-48
(2018/04/11)
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- Silylation-based kinetic resolution of α-hydroxy lactones and lactams
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A silylation-based kinetic resolution has been developed for α-hydroxy lactones and lactams employing the chiral isothiourea catalyst (-)-benzotetramisole and triphenylsilyl chloride as the silyl source. The system is more selective for lactones than lactams, and selectivity factors up to 100 can be achieved utilizing commercially available reagents.
- Clark, Robert W.,Deaton, T. Maxwell,Zhang, Yan,Moore, Maggie I.,Wiskur, Sheryl L.
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supporting information
p. 6132 - 6135
(2014/01/17)
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- Kinetic resolution of racemic 2-hydroxy-γ-butyrolactones by asymmetric esterification using diphenylacetic acid with pivalic anhydride and a chiral acyl-transfer catalyst
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Various optically active 2-hydroxy-γ-butyrolactone derivatives are produced via the kinetic resolution of racemic 2-hydroxy-γ-butyrolactones with diphenylacetic acid using pivalic anhydride and (R)-benzotetramisole ((R)-BTM), a chiral acyl-transfer catalyst. Importantly, the substrate scope of this novel protocol is fairly broad (12 examples, s-value; up to over 1000). In addition, we succeeded in disclosing the reaction mechanism to afford high enantioselectivity using theoretical calculations and expounded on the substituent effects at the C-3 positions in 2-hydroxylactones.
- Nakata, Kenya,Gotoh, Kouya,Ono, Keisuke,Futami, Kengo,Shiina, Isamu
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supporting information
p. 1170 - 1173
(2013/05/21)
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- Modular and stereoselective synthesis of tetrasubstituted helical alkenes via a palladium-catalyzed domino reaction
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A highly modular and stereoselective synthesis of tetrasubstituted helical alkenes is accomplished by a Pd-catalyzed norbornene-mediated domino reaction. This protocol features the rapid assembly of four C-C bonds via sequential C-H activations and carbopalladations along with efficient access to enantiopure bromoalkyl aryl alkyne precursors using homologative alkynylation as the key transformation. Three distinct elements of stereoselectivity were observed in the preparation of the chiral helical alkenes: retention of stereochemistry of the substrates, induced helical diastereoselectivity in the alkene formation, and the exclusive exo-facial selectivity of the norbornene incorporation.
- Liu, Hongqiang,El-Salfiti, Mohamed,Chai, David I.,Auffret, Jeremy,Lautens, Mark
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supporting information; scheme or table
p. 3648 - 3651
(2012/09/08)
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- HETEROCYCLIC DERIVATIVES AS MODULATORS OF ION CHANNELS
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The present invention relates to heterocyclic derivatives useful as inhibitors of ion channels. The invention also provides pharmaceutically acceptable compositions comprising the compounds of the invention and methods of using the compositions in the treatment of various disorders.
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Page/Page column 16
(2009/05/28)
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- HETEROCYCLIC DERIVATIVES AS MODULATORS OF ION CHANNELS
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The present invention relates to heterocyclic derivatives useful as inhibitors of ion channels. The invention also provides pharmaceutically acceptable compositions comprising the compounds of the invention and methods of using the compositions in the treatment of various disorders.
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Page/Page column 20
(2009/05/28)
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- A surprising mechanistic "switch" in Lewis acid activation: A bifunctional, asymmetric approach to α-hydroxy acid derivatives
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We report a detailed synthetic and mechanistic study of an unusual bifunctional, sequential hetero-Diels-Alder/ring-opening reaction in which chiral, metal complexed ketene enolates react with o-quinones to afford highly enantioenriched, α-hydroxylated carbonyl derivatives in excellent yield. A number of Lewis acids were screened in tandem with cinchona alkaloid derivatives; surprisingly, trans-(Ph3P)2PdCl2 was found to afford the most dramatic increase in yield and rate of reaction. A series of Lewis acid binding motifs were explored through molecular modeling, as well as IR, UV, and NMR spectroscopy. Our observations document a fundamental mechanistic "switch", namely the formation of a tandem Lewis base/Lewis acid activated metal enolate in preference to a metal-coordinated quinone species (as observed in other reactions of o-quinone derivatives). This new method was applied to the syntheses of several pharmaceutical targets, each of which was obtained in high yield and enantioselectivity.
- Abraham, Ciby J.,Paull, Daniel H.,Bekele, Tefsit,Scerba, Michael T.,Dudding, Travis,Lectka, Thomas
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supporting information; experimental part
p. 17085 - 17094
(2009/04/13)
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- Epothilon derivatives, method for the production and the use thereof as pharmaceuticals
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Disclosed are epothilone compounds of formula I, which are useful as pharmaceutical compounds for treating, for example, malignant tumors and chronic inflammatory diseases and are useful in anti-angiogenesis therapy.
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Page/Page column 72
(2010/10/19)
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- A METHOD OF PREPARING ENANTIOMERS OF INDOLE-2,3-DIONE-3-OXIME DERIVATIVES
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The present invention is directed to a method of preparing enantiomers of indole-2,3-dione-3-oxime derivatives.
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- Asymmetric reduction of 2-substituted 2-butenolides with reductase from Marchantia polymorpha
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A p68 reductase participating in the asymmetric reduction of the C-C double bond of 2-substituted 2-butenolides was isolated from Marchantia polymorpha. The enzyme reduced 2-substituted 2-butenolides to give (R)-butanolides, and the reduction of citraconic anhydride afforded (R)-methylsuccinic anhydride.
- Shimoda, Kei,Kubota, Naoji
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p. 3827 - 3829
(2007/10/03)
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- EPOTHILONE DERIVATIVES, METHOD FOR PRODUCING SAME AND THEIR PHARMACEUTICAL USE
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This invention relates to the new epothilone derivatives of general formula I, 1in which substituents Y, Z R2a, R2b, R3, R4a, R4b, D—E, R5, R6, R7, R8 and X have the meanings that are indicated in more detail in the description. The new compounds interact with tubulin by stabilizing microtubuli that are formed. They are able to influence the cell-splitting in a phase-specific manner and are suitable for treating malignant tumors, for example, ovarian, stomach, colon, adeno-, breast, lung, head and neck carcinomas, malignant melanomas, acute lymphocytic and myelocytic leukemia. In addition, they are suitable for anti-angiogenesis therapy as well as for treatment of chronic inflammatory diseases (psoriasis, arthritis). To avoid uncontrolled proliferation of cells and for better compatibility of medical implants, they can be applied or introduced into polymer materials. The compounds according to the invention can be used alone or to achieve additive or synergistic actions in combination with other principles and classes of substances that can be used in tumor therapy.
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- Syntheses of fluorinated ligands to probe binding of antigenic determinants of Vibrio cholerae O:1, serotypes Inaba and Ogawa, to antibodies
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Derivatives of methyl α-glycosides of antigenic determinants of Vibrio cholerae O:1, serotypes Inaba and Ogawa, specifically fluorinated at position 2' or 4' have been synthesized by coupling the appropriately fluorinated derivatives of 3-deoxy-L-glycero-tetronic acid with the methyl α-glycosides of perosamine. The compound having the fluorine atom at position 2 was obtained by electrophilic addition of fluorine to the glycal derived from the parent antigenic determinant, serotypes Inaba, using Selectfluor((TM)) as a fluorination reagent. Copyright (C) 2000 Elsevier Science Ltd.
- Chang, Alex H.C.,Horton, Derek,Kovac, Pavol
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p. 595 - 606
(2007/10/03)
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- Preparation of chiral pyrrolidinone derivatives
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A process for preparing a compound of formula IIa or IIb: STR1 wherein R2, R3, R4 and R5 independently represent hydrogen or C1 -C4 alkyl; and A is an optionally substituted aromatic or heteroaromatic ring system; the process comprising the steps of: (a) reacting a racemic mixture of a compound of formula II: STR2 wherein R2, R3, R4, R5 and A are as defined for formulae IIa and IIb; with a sterically hindered chiral esterifying agent to form enantiomers of formulae IIIa and IIIb: STR3 wherein R2, R3, R4, R5 and A are as defined for formulae IIa and IIb and R15 is a chiral sterically hindered residue; b) separating the diastereoisomers of formulae IIIa and IIIb; and (c) converting the diastereoisomers of formulae IIIa and IIIb separately to compounds of formulae IIa and IIb respectively by acid or base hydrolysis. If required, the unwanted enantiomer of formula IIa or IIb may be inverted to give the preferred isomer.
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