- The Synthesis of the High-Potency Sweetener, NC-00637. Part 3: The Glutamyl Moiety and Coupling Reactions
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The synthesis of the high-potency sweetener, NC-00637 (1), required selective preparation of the γ-protected glutamic acid. Coupling of the three components could be performed in any order, but the final route involved N-acylation of the protected L-glutamic acid with the acid chloride derived from (S)-2-methylhexanoic acid. Activation of the α-carboxyl group allowed condensation with 5-amino-2-cyanopyridine (4). Saponification of the γ-ester 19 then provided the sweetener 1.
- Ager, David J.,Babler, Scott,Erickson, Robert A.,Froen, Diane E.,Kittleson, Jeannine,Pantaleone, David P.,Prakash, Indra,Zhi, Ben
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- Enantiodifferentiating Properties of the Alignment Media PELG and PBLG - A Comparison
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Homopolypeptide-based alignment media can induce different orientations of enantiomers as a result of their α-helical structures. This property enables the discrimination of enantiomers through anisotropic NMR parameters such as residual dipolar couplings (RDCs). In this paper, the enantiodiscriminating properties of two alignment media derived from polyglutamic acid derivatives - poly-γ-benzyl-L-glutamate (PBLG) and poly-γ-ethyl-L-glutamate (PELG) - are compared and discussed. The two analytes, isopinocampheol and β-pinene, are investigated, and the role of the lateral side chain of the homopolypeptide in the orientation process is examined. Lyotropic liquid crystalline phases of poly-γ-benzyl-L-glutamate (PBLG) and poly-γ-ethyl-L-glutamate (PELG) are used to measure the residual dipolar couplings of the enantiomers of isopinocampheol and β-pinene. A comparison and investigation of the enantiodifferentiating behavior of these homopolypeptides provide new insight into the alignment process.
- Hansmann, Stefanie,Larem, Tobias,Thiele, Christina M.
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- Synthesis method of vildagliptin
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The invention discloses a synthesis method of vildagliptin. The method comprises the following steps: performing esterification reaction on L-glutamic acid and ethanol to obtain L-glutamic acid-gamma-ethyl ester; reducing the L-glutamic acid-gamma-ethyl ester under the action of potassium borohydride to obtain L-proline; mixing L-proline with ethyl chloroformate for reaction to obtain acid anhydride; further reacting the acid anhydride with amine to obtain amide; dehydrating the amide under the action of phosphorus pentoxide to obtain an intermediate 1; performing substitution reaction on theintermediate 1 and chloroacetyl chloride to obtain an intermediate 2; and further reacting the intermediate 2 with 3-amino-1-adamantanol to obtain vildagliptin. The method has the advantages that fewimpurities are generated in the vildagliptin preparation process, the yield of the prepared vildagliptin is high, and compared with the prior art, the process is simpler, and the vildagliptin preparation cost is greatly reduced.
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Paragraph 0031-0033; 0038-0040; 0045-0047
(2020/09/12)
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- Further Insights on Structural Modifications of Muramyl Dipeptides to Study the Human NOD2 Stimulating Activity
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A series of muramyl dipeptide (MDP) analogues with structural modifications at the C4 position of MurNAc and on the d-iso-glutamine (isoGln) residue of the peptide part were synthesized. The C4-diversification of MurNAc was conveniently achieved by using CuAAC click strategy to conjugate an azido muramyl dipeptide precursor with structurally diverse alkynes. d-Glutamic acid (Glu), replaced with isoGln, was applied for the structural diversity through esterification or amidation of the carboxylic acid. In total, 26 MDP analogues were synthesized and bio-evaluated for the study of human NOD2 stimulation activity in the innate immune response. Interestingly, MDP derivatives with an ester moiety are found to be more potent than reference compound MDP itself or MDP analogues containing an amide moiety. Among the varied lengths of the alkyl chain in ester derivatives, the MDP analogue bearing the d-glutamate dodecyl (C12) ester moiety showed the best NOD2 stimulation potency.
- Cheng, Wei-Chieh,You, Ting-Yun,Teo, Zhen-Zhuo,Sayyad, Ashik A.,Maharana, Jitendra,Guo, Chih-Wei,Liang, Pi-Hui,Lin, Chung-Shun,Meng, Fan-Chun
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supporting information
p. 3836 - 3844
(2020/10/21)
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- Butyryl glutamic acid derivative as well as composition and application thereof
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The invention discloses a butyryl glutamic acid derivative as well as a composition and application thereof. The butyryl glutamic acid derivative disclosed by the invention or a racemic modification,stereisomer, geometric isomer, tautomer and solvate or feed-acceptable salt thereof can be applied in the preparation of novel feed additives and feeds. The invention further discloses a feed composition of the butyryl glutamic acid derivative or the racemic modification, the stereisomer, the geometric isomer, the tautomer and the solvate or the feed-acceptable salt thereof. When applied in animalhusbandry, the butyryl glutamic acid derivative provided by the invention has the effect of improving the production performance of animals, such as increasing animal weight increasing rate, decreasing feed conversion ratio and controlling diarrhea rate, and can be applied as an effective, safe novel feed additive.
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Paragraph 0154; 0155
(2018/07/30)
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- Method for synthesizing L-glutamic acid-gamma-ethyl ester of L-proline medicine intermediates
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The invention discloses a method for synthesizing L-glutamic acid-gamma-ethyl ester of L-proline medicine intermediates. The method includes a step of (i), adding 1.1 mol of L-glutamic acid (2) and 1200 ml of phenethyl alcohol solution into reaction vessels with stirrers, temperature gauges, reflux condensers and dropping funnels at the stirring speeds of 120-150 rpm under the control to obtain solution, reducing the temperature of the solution until the temperature of the solution reaches 3-5 DEG C, slowly adding 100-120 ml of phosphoric acid solution into the solution, then carrying out reaction for 90-120 min to obtain solution, increasing the temperature of the solution until the temperature of the solution reaches 40-45 DEG C, carrying out reaction for 80-120 min, clearing reaction liquid, adding 50 ml of potassium bicarbonate solution into the reaction liquid to obtain solution, keeping the pH (potential of hydrogen) of the solution at 9-10, dissolving out white solid, reducing the temperature of the solution at the stirring speeds of 160-180 rpm under the control until the temperature of the solution reaches 30-35 DEG C, carrying out reaction for 90-120 min to obtain solution, reducing the temperature of the solution until the temperature of the solution reaches 7-10 DEG C, filtering the solution, washing filter cakes by the aid of p-xylene solution and drying the filter cakes under low pressures to obtain the L-glutamic acid-gamma-ethyl ester. The mass fraction of the phenethyl alcohol solution is 85-90% in the step (i), and the mass fraction of the phosphoric acid solution is 90-95% in the step (i).
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Paragraph 0014; 0015
(2016/11/21)
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- Synthesis and physicochemical characterization of the impurities of pemetrexed disodium, an anticancer drug
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A physicochemical characterization of the process-related impurities associated with the synthesis of pemetrexed disodium was performed. The possibility of pemetrexed impurities forming has been mentioned in literature, but no study on their structure has been published yet. This paper describes the development of the synthesis methods for these compounds and discusses their structure elucidation on the basis of two-dimensional NMR experiments and MS data. The identification of these impurities should be useful for the quality control during the production of the pemetrexed disodium salt.
- Michalak, Olga,Gruza, Mariusz M.,Witkowska, Anna,Bujak, Iwona,Cmoch, Piotr
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supporting information
p. 10004 - 10031
(2015/08/06)
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- Double asymmetric induction in organocatalyzed aldol reactions: Total synthesis of (+)-2-epi-hyacinthacine A2 and (-)-3-epi-hyacinthacine A1
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The stereodivergent synthesis of two hyacinthacine analogues, which relies on an organocatalyzed aldol addition, is described. The aldol addition of dioxanone to an α-N-carbobenzyloxy-substituted chiral aldehyde, promoted by both (R)- and (S)-proline, pro
- Marjanovic, Jasna,Divjakovic, Vladimir,Matovic, Radomir,Ferjancic, Zorana,Saicic, Radomir N.
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supporting information
p. 5555 - 5560
(2013/09/12)
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- Heterocyclic sulfonamide inhibitors of beta amyloid production
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Compounds of Formula (I), wherein R1, R2, R3, R4, R5, R6, T, W, X, Y and Z are as defined herein are provided, together with pharmaceutically acceptable salt, hydrates and/or prodrugs there
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- A Simple and Convenient Synthesis of β-Aspartates and γ-Glutamates
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A simple and convenient, high yield synthesis of ω-esters of aspartic as well as glutamic acid has been developed, using tetrafluoroboric acid as catalyst. (13)C-NMR data of the products are given.
- Albert, Rainer,Danklmaier, Johann,Hoenig, Helmut,Kandolf, Harald
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p. 635 - 637
(2007/10/02)
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