- Solid-phase synthesis and opioid activities of [D-Ala2]Deltorphin II analogs
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[D-Ala2]Deltorphin II (DL-II) analogs having various aliphatic amino acids at positions 5 and 6 were synthesized by a solid-phase method and their opioid activities on electrically induced guinea pig ileum (GPI) and mouse vas deferens (MVD) preparations were determined. During the synthesis of an analog, [tert-leucine(Tle)5,6]DL-II, we encountered difficulty in the coupling reaction between Tle5 and Tle6 with the usual diisopropylcarbodiimide (DIPCDI)-mediated tert-butoxycarbonyl (Boc) strategy, though the other analogs could be successfully synthesized. We found that the fluorenylmethoxycarbonyl (Fmoc)-Tle/DIPCDI/1-hydroxybenztriazole method was very useful for the synthesis of such a peptide having a sterically hindered sequence. Acid hydrolysis studies of the synthetic analogs suggested that the steric hindrance of consecutive aliphatic amino acid sequences depend upon the degree of branching at the β-carbon atom of the amino acids. In the MVD assay, two analogs, [Ala5,6] and [Tle5,6]DL-II showed remarkably low potencies while other analogs with Nva5,6, Nle5,6, Ile5,6, Leu5,6 and Mle5,6 substituted for Val5,6(DL-II) showed comparable or slightly lower potencies than DL-II. In the GPI assay, no remarkable changes in potency were observed between DL-II and this series of analogs. Conformational aspects of synthetic analogs were examined by comparing the circular dichroism spectra.
- Sasaki,Ambo,Midorikawa,Suzuki
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- Method for synthesizing chiral N-substituted-alpha-amino acid compound through chemical resolution
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The invention belongs to the technical field of preparation of N-substituted-alpha-amino acid compounds, and particularly relates to a method for synthesizing a chiral N-substituted-alpha-amino acid compound through chemical resolution. The method comprises the following steps: mixing a racemate N-substituted-alpha-amino acid compound with phenylglycinol to form a salt, and adding an acid for neutralization to obtain a single-configuration chiral target product, wherein the N-substituted-alpha-amino acid compound is N-substituted-2-amino-4,4-dimethyl valeric acid, and an N-substituted amino protecting group is an alkoxycarbonyl group, an enoxycarbonyl group, an aryloxycarbonyl group or an alkylacyl group. According to the method, chiral phenylglycinol which is low in cost and stable in property is used as a resolution reagent, and N-substituted alpha-amyl amino acid can be well resolved; and R-configuration or S-configuration enantiomers are respectively obtained. The method is high inyield, good in purity, low in cost and suitable for industrial production.
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- Preparation method of N-Boc-(R)-2-amino-4, 4-dimethylvaleric acid
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Belonging to the field of organic synthesis, the invention discloses a preparation method of N-Boc-(R)-2-amino-4, 4-dimethylvaleric acid. The preparation method of N-Boc-(R)-2-amino-4, 4-dimethylvaleric acid includes a synthetic route shown as the specification. The preparation method of N-Boc-(R)-2-amino-4, 4-dimethylvaleric acid provided by the invention has the advantages of cheap and easily available raw materials, low cost, convenient process operation, safety and high product yield, is suitable for industrial production, and has broad application prospects.
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- Preparation method of N-alkoxy or benzyloxycarbonyl chiral amino acid
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The invention provides a preparation method of N-alkoxy or benzyloxycarbonyl amino acid, particularly provides a preparation method of N-alkoxy or benzyloxycarbonyl chiral amino acid, and more particularly provides a preparation method of N-alkoxy or benzyloxycarbonyl-L-amino acid or N-alkoxy or benzyloxycarbonyl-D-amino acid. In the preparation method, a resolving agent is not required for chemical resolution, and the N-alkoxy or benzyloxycarbonyl chiral amino acid with high optical purity can be prepared. The N-alkoxy or benzyloxycarbonyl chiral amino acid is a very important medicine intermediate. According to the preparation method of the N-alkoxy or benzyloxycarbonyl-L-amino acid, provided by the invention, a reaction formula is as follows in the description, wherein R1 is an alkyl group, preferably a tert-butyl group; R2 is an azido group or an imide group, n is 0 or 1, and m is 1.
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Paragraph 0050-0052
(2018/03/24)
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- Enantioselective Friedel-Crafts reactions between phenols and N-tosylaldimines catalyzed by a leucine-derived bifunctional catalyst
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Enantioselective Friedel-Crafts reactions between phenols and N-tosylaldimines were developed using a bifunctional catalyst readily prepared from l-leucine. The chiral benzylic amine products were obtained in high yields (up to 96% yield) and good to high enantiomeric excesses (up to 95% ee).
- Li, Guo-Xing,Qu, Jin
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supporting information; experimental part
p. 5518 - 5520
(2012/07/01)
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- LYSOBACTIN AMIDES
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The invention relates to lysobactin amides and methods for their preparation, as well as their use for manufacturing medicaments for the treatment and/or prophylaxis of diseases, in particular bacterial infectious diseases.
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- New Aza-Bicyclohexane Compounds Useful As Inhibitors Of Thrombin
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This invention relates to novel pharmaceutically useful compounds of formula (I), in particular compounds that are competitive inhibitors of trypsin-like serine proteases, especially thrombin, their use as medicaments, pharmaceutical compositions containi
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Page/Page column 15, 16
(2009/01/23)
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- HETEROBICYCLIC METALLOPROTEASE INHIBITORS
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The present invention relates generally to amide group containing pharmaceutical agents, and in particular, to amide containing heterobicyclic metalloprotease inhibitor compounds. More particularly, the present invention provides a new class of heterobicyclic MMP- 13 inhibiting compounds, that exhibit an increased potency in relation to currently known MMP- 13 inhibitors.
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Page/Page column 222
(2008/06/13)
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- Exploration of the P1 SAR of aldehyde cathepsin K inhibitors.
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The synthesis and biological activity of a series of aldehyde inhibitors of cathepsin K are reported. Exploration of the properties of the S(1) subsite with a series of alpha-amino aldehyde derivatives substituted at the P(1) position afforded compounds with cathepsin K IC(50)s between 52 microM and 15 nM.
- Catalano, John G,Deaton, David N,Furfine, Eric S,Hassell, Annie M,McFadyen, Robert B,Miller, Aaron B,Miller, Larry R,Shewchuk, Lisa M,Willard Jr., Derril H,Wright, Lois L
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p. 275 - 278
(2007/10/03)
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- Protease inhibitors
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The present invention provides compounds of formula (I) which inhibit proteases, including cathepsin K, pharmaceutical compositions of such compounds, and methods for treating diseases of excessive bone loss or cartilage or matrix degradation, including osteoporosis; gingival disease including gingivitis and periodontitis; arthritis, more specifically, osteoarthritis and rheumatoid arthritis; Paget's disease; hypercalcemia or malignancy; and metabolic bone disease therewith.
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- PEPTIDES CONTAINING A NEOPENTYLGLYCINE RESIDUE
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Neopentylglycine (III, 2-amino-4,4-dimethylpentanoic acid) was synthesized in both enantiomeric forms.Using the conventional methods of peptide synthesis, L-prolyl-L-neopentylglycylglycine amide (VII), the diastereomeric cyclodipeptides cyclo(L-neopentylglycyl-L-prolyl) (IXa) and cyclo(D-neopentylglycyl-L-prolyl) (IXb) and also N-acetyl-L-neopentylglycine methylamide (X) were prepared as models for further studies on physical properties and conformation of peptides.
- Pospisek, Jan,Blaha, Karel
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p. 514 - 521
(2007/10/02)
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