- Synthesis and utility of a novel methylene Meldrum's acid precursor
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The betaine 1-[(6-hydroxy-2,2-dimethyl-4-oxo-4H-1,3-dioxin-5-yl)methyl]pyridinium hydroxide, inner salt (1), a pyridine adduct of methylene Meldrum's acid is a stable source of methylene Meldrum's acid. It is a versatile reagent which enhances the yields of Diels-Alder and Michael reactions when used instead of traditional methods that generate methylene Meldrum's acid in situ. Diels-Alder reactions performed with this reagent provide products in essentially quantitative yields. Michael reactions result in products in excess of 70% yield. This reagent provides a useful synthetic route to γ-carboxyglutamic acid.
- Zia-Ebrahimi,Huffman
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- USE OF COMPOUNDS IN THE TREATMENT OF ISCHEMIA AND NEURODEGENERATION
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TPP II (tripeptidyl peptidase II) inhibitors are useful in the treatment of a neurodegenerative disease, for example Alzheimer's, Parkinson's or Huntingdon's disease or an ischemic condition, for example stroke and cardiac infarction. Suitable compounds comprise tripeptide compounds of general formula RN1RN2N-A1-A2-A3-CO—RC1 wherein RN1, RN2, A1, A2, A3 and RC1 are as defined herein, and which include for example the tripeptide sequences GLA and GPG.
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- Azapeptides useful in the treatment of Hepatitis C
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The present invention relates to azapeptide compounds represented by the formula: pharmaceutical compositions containing such compounds, and the use thereof in the treatment of Hepatitis C viral infections.
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- The synthesis and properties of Gla- and Phe-containing analogues of cyclic RGD pentapeptides
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Cyclopentapeptides containing the Arg-Gly-Asp motif have been synthesised using solid-phase assembly of side-chain-protected linear precursors, followed by solution-phase cyclisation. The replacement of the Asp residue by γ-carboxyglutamic acid (Gla) is a novel feature which gives rise to an analogue which inhibits cell adhesion, yet its congeners do not show activity in binding assays with recombinant integrin receptors. NMR techniques support a β/γ-turn conformation in most of the analogues. The Royal Society of Chemistry 2000.
- Davies, John S.,Enjalbal, Christine,Nguyen, Corrine,Al-Jamri, Loai,Naumer, Christian
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p. 2907 - 2915
(2007/10/03)
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- A NEW SYNTHETIC EQUIVALENT OF THE GLUTAMIC ACID γ-ANION AND ITS APPLICATION TO THE SYNTHESIS OF S-(+)-γ-CARBOXYGLUTAMIC ACID
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Protected S-pyroglutamic acid can be deprotonated specifically at the γ-position.The resulting enolate can be converted into γ-carboxyglutamic acid in optically pure form.
- Attwood, Michael R.,Carr, Maria G.,Jordan, Steven
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p. 283 - 284
(2007/10/02)
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- A New Approach for the Total Synthesis of L-γ-Carboxyglutamic Acid: Utility of Ruthenium Tetroxide Oxidation
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A new and convenient synthesis of optically pure L-γ-carboxyglutamic acid (L-Gla)(1) from L-proline as a chiral source was developed.Protection of N-tert-butyloxycarbonyl(Boc)prolinol (4) with a tert-butyldimethylsilyl group followed by oxidation with ruthenium tetroxide (RuO4) afforded the corresponding lactam compound (6), which was carboxylated with lithium diisopropylamide and benzyloxycarbonylimidazole to afford the 4-benzyloxycarbonyl lactam derivative (7).Selective removal of the silyl group from 7, followed by oxidation of the resulting alcohol (8) with pyridinium dichromate gave the carboxylic acid, which was converted into the ester derivatives (10b-d).Cleavage of the lactam bond of 10b with excess benzyl alcohol in the presence of triethylamine gave γ,γ,α-tribenzyl N-Boc-L-γ-carboxyglutamate (11).Finally, 11 was hydrogenated over Pd on charcoal and deprotected with trifluoroacetic acid to produce L-γ-carboxyglutamic acid (1).Keywords - L-γ-carboxyglutamic acid; ruthenium tetroxide oxidation; carboxylation; L-proline; L-prolinol; 1-benzyloxycarbonylimidazole; 4-benzyloxycarbonyl-1-tert-butyloxycarbonyl-L-pyroglutamic acid ester; catalytic hydrogenation; trifluoroacetic acid deprotection
- Tanaka, Ken-ichi,Yoshifuji, Shigeyuki,Nitta, Yoshihiro
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p. 3879 - 3884
(2007/10/02)
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- ENZYMATIC RESOLUTION OF γ-CARBOXY-DL-GLUTAMIC ACID
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Optically active γ-carboxy-L-glutamic acid was prepared by enantioselective reaction of benzyloxycarbonyl-γ-carboxy-DL-glutamic acid with phenylhydrazine, catalyzed by papain (E.C.3.4.22.2), and subsequent removal of the protecting groups from the obtained benzyloxycarbonyl-γ-carboxyl-L-glutamic acid α-phenylhydrazide.
- Cerovsky, Vaclav,Jost, Karel
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p. 2562 - 2565
(2007/10/02)
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