- Regioselectivity in the Catalytic Hydrogenolysis of 1-Amino-1-cyclopropanecarboxylic Acid and Its Methyl Ester
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The title compounds were hydrogenolyzed over Pd-C.The ring-bond cleavage in the hydrogenolysis of the acid in water or methanol occurred at both the C1-C2 bond and the C2-C3 bond in nearly equal proportion, whereas the C1-C2 bond was cleaved mainly in the presence of ammonia and the C2-C3 bond was cleaved mainly in acetic acid.Selective hydrogenolysis of the C1-C2 bond of ester occurred in hexane or methanol, whereas the C2-C3 bond was hydrogenolyzed mainly in acetic acid.The role of the amino group is discussed.
- Isogai, Koji,Sakai, Jun-ichi,Yamauchi, Keiji,Watanabe, Katsuya
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- N halo derivatives III: Stabilization of nitrogen chlorine bond in N chloroamino acid derivatives
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The chlorination of α amino acids and their related derivatives was investigated. A kinetic study of the stability of these N chlorinated products led to an elucidation of the factors that significantly influence the stability and research of the nitrogen chlorine bond in these N chloramines. From the kinetic investigations, a series of low chlorine potential, soft antimicrobial N chloramines was developed based on derivatives of α aminoisobutyric acid and related compounds.
- Kaminski,Bodor,Higuchi
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- Structural characterization of folded pentapeptides containing centrally positioned β(R)Val, γ(R)Val and γ(S)Val residues
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A cylindrical pore of ～7.5 diameter containing a one-dimensional water wire, within the confines of a hydrophobic channel lined with the valine side chain, has been observed in crystals of the peptide Boc-d-Pro-Aib-Val-Aib-Val- OMe (1) (Raghavender et al., 2009, 2010). The synthesis and structural characterization in crystals of three backbone homologated analogues Boc-d-Pro-Aib-β3(R)Val-Aib-Val-OMe (2), Boc-d-Pro-Aib- γ4(R)Val-Aib-Val-OMe (3), Boc-d-Pro-Aib-γ4(S) Val-Aib-Val-OMe (4) are described. Crystal structures of peptides 2, 3 and 4 reveal close-packed arrangements in which no pore was formed. In peptides 2 and 3 the N-terminus d-Pro-Aib segment adopted conformations closely related to Type II′ β-turns, while residues 2-4 form one turn of an αβ right-handed C11 helix in 2 and an αγ C12 helix in 3. In peptide 4, a continuous left-handed helical structure was observed with the d-Pro-Aib segment forming a Type III′ β-turn, followed by one turn of a left-handed αγ C12 helix.
- Dinesh, Bhimareddy,Basuroy, Krishnayan,Shamala, Narayanaswamy,Balaram, Padmanabhan
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- Novel tenofovir mixed ester-amide prodrugs
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The invention relates to novel tenofovir mixed ester-amide prodrugs or pharmaceutically acceptable salts thereof, a preparation method thereof, pharmaceutical compositions containing the prodrug compounds, and application of the prodrugs in preparation of drugs for treating virus infection such as hepatitis B virus (HBV) or human immunodeficiency virus (HIV) infection.
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Paragraph 0129-0131
(2020/04/17)
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- Tetrazole as a Replacement of the Electrophilic Group in Characteristic Prolyl Oligopeptidase Inhibitors
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4-Phenylbutanoyl-aminoacyl-2(S)-tetrazolylpyrrolidines were studied as prolyl oligopeptidase inhibitors. The compounds were more potent than expected from the assumption that the tetrazole would also here be a bioisostere of the carboxylic acid group and the corresponding carboxylic acids are at their best only weak inhibitors. The aminoacyl groups l-prolyl and l-alanyl gave potent inhibitors with IC50 values of 12 and 129 nM, respectively. This was in line with typical prolyl oligopeptidase inhibitors; however, we did observe a difference with N-methyl-l-alanyl, which gave potent inhibitors in typical prolyl oligopeptidase inhibitors but not in our novel compound series. Furthermore, all studied 4-phenylbutanoyl-aminoacyl-2(S)-tetrazolylpyrrolidines decreased α-synuclein dimerization at the concentration of 10 μM, also when they were only weak inhibitors of the proteolytic activity of the enzyme with an IC50 value of 205 μM. Molecular docking studies revealed that the compounds are likely to bind differently to the enzyme compared to typical prolyl oligopeptidase inhibitors represented in this study by 4-phenylbutanoyl-aminoacyl-2(S)-cyanopyrrolidines.
- Kilpel?inen, Tommi P.,Tyni, Jonna K.,Lahtela-Kakkonen, Maija K.,Etel?inen, Tony S.,My?h?nen, Timo T.,Wallén, Erik A. A.
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supporting information
p. 1635 - 1640
(2019/12/02)
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- Crystallographic insight-guided nanoarchitectonics and conductivity modulation of an n-type organic semiconductor through peptide conjugation
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Crystallographic insight-guided nanoarchitectonics of peptide-conjugated naphthalene diimide (NDI) is described. In a bio-inspired approach, non-proteinogenic α-amino isobutyric acid (Aib)- and alanine (Ala)-derived peptides orchestrated the 1D achiral and 2D chiral molecular ordering of NDI, respectively, which resulted in modulation of nanoscale morphology, chiroptical and conductivity properties.
- Pandeeswar,Khare, Harshavardhan,Ramakumar, Suryanarayanarao,Govindaraju
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supporting information
p. 8315 - 8318
(2015/05/13)
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- Synthesis of peptides employing protected-amino acid halides mediated by commercial anion exchange resin
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Coupling of protected-amino acid halides (chloride, fluoride) mediated by commercial anion exchange resin for the solution phase synthesis of peptides is described. The reaction was carried out in an organic medium, circumventing the use of an organic base or an inorganic base. The coupling is fast, clean and racemization free. The anion exchange resin functions as a solid-phase basic scavenger, soaking up the HCl produced and allowing the amine to react. The method is extended for the coupling of sterically hindered α,α,- dialkylamino acids. Graphical Abstract: [Figure not available: see fulltext.]
- Bhaskara Redddy,Kumari, Y. Bharathi,Ananda, Kuppanna
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p. 225 - 229
(2013/12/04)
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- PIPECOLIC LINKER AND ITS USE FOR CHEMISTRY ON SOLID SUPPORT
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The present invention relates to a pipecolic linker and its use as a solid-phase linker in organic synthesis. Said pipecolic solid-phase linker may be used for coupling functional groups chosen between primary amines, secondary amines, aromatic amines, alcohols, phenols and thiols. In particular, said pipecolic solid-phase linker may be used for peptide or pseudopeptide synthesis, such as the reverse N to C peptide synthesis or the retro-inverso peptide synthesis, or for the synthesis of small organic molecules.
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Page/Page column 31-32
(2010/04/06)
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- 1, 2 DISUBSTITUTED HETEROCYCLIC COMPOUNDS
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1,2-disubstituted heterocyclic compounds which are inhibitors of phosphodiesterase 10 are described. Also described are processes, pharmaceutical compositions, pharmaceutical preparations and pharmaceutical use of the compounds in the treatment of mammals, including human(s) for central nervous system (CNS) disorders and other disorders which may affect CNS function. Among the disorders which may be treated are neurological, neurodegenerative and psychiatric disorders including, but not limited to, those associated with cognitive deficits or schizophrenic symptoms.
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Page/Page column 56
(2010/01/30)
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- Asperelines A-F, peptaibols from the marine-derived fungus Trichoderma asperellum
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Fermentation of the marine-derived fungus Trichoderma asperellum, collected from the sediment of the Antarctic Penguin Island, resulted in the isolation of six new peptaibols named asperelines A-F (1-6), which are characterized by an acetylated N-terminus and a C-terminus containing an uncommon prolinol residue. Structures were determined by extensive 1D and 2D NMR (1H- 1H COSY, HMQC, HMBC, NOESY) spectroscopic data analysis combined with ESIMS/MS fragmentation. The absolute configurations of the amino acid residues possessing a chiral R-carbon and of the prolinol residue were determined to be L and S, respectively, using a new method of 1H NMR spectroscopic comparison of complexes formed between the chiral reagent Ru(D 4-Por*)CO and amino acids derived from the peptaibols with those formed with reference standards.
- Ren, Jinwei,Xue, Chunmei,Tian, Li,Xu, Minjuan,Chen, Jian,Deng, Zhiwei,Proksch, Peter,Lin, Wenhan
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experimental part
p. 1036 - 1044
(2011/02/28)
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- Characterization of the binding properties of SIRT2 inhibitors with a N-(3-phenylpropenoyl)-glycine tryptamide backbone
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SIRT2 inhibitors with a N-(3-phenylpropenoyl)-glycine tryptamide backbone were studied. This backbone has been developed in our group, and it is derived from a compound originally found by virtual screening. In addition, compounds with a smaller 3-phenylpropenoic acid tryptamide backbone were also included in the study. Binding modes for the new compounds and the previously reported compounds were analyzed with molecular modelling methods. The approach, which included a combination of molecular dynamics, molecular docking and cluster analysis, showed that certain docking poses were favourable despite the conformational variation in the target protein. The N-(3-phenylpropenoyl)-glycine tryptamide backbone is also a good backbone for SIRT2 inhibitors, and the series of compounds includes several potent SIRT2 inhibitors.
- Kiviranta, Paeivi H.,Salo, Heikki S.,Leppaenen, Jukka,Rinne, Valtteri M.,Kyrylenko, Sergiy,Kuusisto, Erkki,Suuronen, Tiina,Salminen, Antero,Poso, Antti,Lahtela-Kakkonen, Maija,Wallen, Erik A.A.
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p. 8054 - 8062
(2008/12/23)
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- Potential anti-inflammatory actions of the elmiric (lipoamino) acids
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A library of amino acid-fatty acid conjugates (elmiric acids) was synthesized and evaluated for activity as potential anti-inflammatory agents. The compounds were tested in vitro for their effects on cell proliferation and prostaglandin production, and compared with their effects on in vivo models of inflammation. LPS stimulated RAW 267.4 mouse macrophage cells were the in vitro model and phorbol ester-induced mouse ear edema served as the principal in vivo model. The prostaglandin responses were found to be strongly dependent on the nature of the fatty acid part of the molecule. Polyunsaturated acid conjugates produced a marked increase in media levels of i15-deoxy-PGJ2 with minimal effects on PGE production. It is reported in the literature that prostaglandin ratios in which the J series predominates over the E series promote the resolution of inflammatory conditions. Several of the elmiric acids tested here produced such favorable ratios suggesting that their potential anti-inflammatory activity occurs via a novel mechanism of action. The ear edema assay results were generally in agreement with the prostaglandin assay findings indicating a connection between them.
- Burstein, Sumner H.,Adams, Jeffrey K.,Bradshaw, Heather B.,Fraioli, Cristian,Rossetti, Ronald G.,Salmonsen, Rebecca A.,Shaw, John W.,Walker, J. Michael,Zipkin, Robert E.,Zurier, Robert B.
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p. 3345 - 3355
(2008/02/09)
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- N-(3-(4-Hydroxyphenyl)-propenoyl)-amino acid tryptamides as SIRT2 inhibitors
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A series of N-(3-(4-hydroxyphenyl)-propenoyl)-amino acid tryptamides was based on a previously reported new SIRT2 inhibitor from our group, and it was designed to study if the molecular size of the compound could be reduced. The most potent compounds, N-(3-(4-hydroxyphenyl)-propenoyl)-2-aminoisobutyric acid tryptamide and N-(3-(4-hydroxyphenyl)-propenoyl)-l-alanine tryptamide, were equipotent, 30% smaller in molecular weight, and slightly more selective (SIRT2/SIRT1) than the parent compound.
- Kiviranta, Paeivi H.,Leppaenen, Jukka,Rinne, Valtteri M.,Suuronen, Tiina,Kyrylenko, Olga,Kyrylenko, Sergiy,Kuusisto, Erkki,Tervo, Anu J.,Jaervinen, Tomi,Salminen, Antero,Poso, Antti,Wallen, Erik A.A.
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p. 2448 - 2451
(2008/02/03)
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- Methods and compositions for treating amyloid-related diseases
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Methods, compounds, pharmaceutical compositions and kits are described for treating or preventing amyloid-related disease.
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Page/Page column 170
(2010/11/24)
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- But-2-ynylbisoxycarbonyl chloride: A novel C2-symmetric reagent for the protection of amines and amino acids
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(Chemical Equation Presented) A novel C2-symmetric protecting group for amines, the but-2-ynylbisoxycarbonyl (Bbc) group, is developed, which can be deblocked with tetrathiomolybdate under neutral conditions. One equivalent of the bischloroformate, BbcCl, is used for the protection of 2 equiv of the amine. Its application in peptide synthesis is established through the synthesis of a tripeptide, and its orthogonality with Cbz, Fmoc, and Boc groups has been studied.
- Ramesh,Chandrasekaran
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p. 4947 - 4950
(2007/10/03)
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- Substituent effect on acidity of substituted 2-(4-nitrobenzoylamino)alkanamidesin methanol-dimethyl sulfoxide mixtures
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The dissociation constants of substituted 2-(4-nitrobenzoylamino)alkanamides, N-[2-(4-nitrobenzoylamino)aikanoyl]pyrrolidines, and N-alkyl-4-nitrobenzamides have been measured spectrophotometrically in 60 and 80% v/v DMSO. The pKA values of these N-acids are discussed from the point of view of substituents at the acetamide a-carbon atom.
- Mitas, Petr,Sedlak, Milos,Kavalek, Jaromir
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- Amino acid amides of 1,3,4-thiadiazoles as matrix metalloproteinase
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Amino acid amides of 5-amino-1,3,4-thiadiazole-2-thione are disclosed. These compounds inhibit matrix metalloproteinase enzymes and cartilage degradation. Methods of treating diseases caused by over-activity of matrix metalloproteinases, such as osteoarth
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- Reaction of Silyl Enol Ethers with Arenediazonium Salts. Part 2. α-Amination of Esters
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Diazonium salts efficiently serve as electrophilic aminating reagents of esters.The reaction of arenediazonium tetrafluoroborates with ketene silyl ketals yielded α-azo or α-hydrazono esters in good to excellent yields under very mild conditions.Hydrogenation of those esters gave α-amino esters quantitatively.
- Sakakura, Toshiyasu,Hara, Masayasu,Tanaka, Masato
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p. 289 - 294
(2007/10/02)
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- Selective Amide Cleavage in Peptides Containing α,α-Disubstituted α-Amino Acids
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A new synthesis of dipeptides with terminal α,α-disubstituted α-amino acids, using 2,2-disubstituted 3-amino-2H-azirines 1 as amino-acid equivalents, is demonstrated.The reaction of 1 with N-protected amino acids leads to the corresponding dipeptide amide
- Wipf, Peter,Heimgartner, Heinz
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p. 354 - 368
(2007/10/02)
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- Reaction of Ketene Silyl Acetals with Diazonium Salts: a Novel α-Amino Acid Ester Synthesis
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The reaction of ketene silyl acetals with arenediazonium tetrafluoroborate gave α-hydrazono and α-azo esters, which were easily hydrogenated to α-amino esters.
- Sakakura, Toshiyasu,Tanaka, Masato
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p. 1309 - 1310
(2007/10/02)
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- Tumor-resolving and histolytic medicaments and their use
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Dehydrooligopeptides, some of which are known, demonstrate histolytic and tumor-resolving activity and may be used in medicaments causing the lysis of animal tissues and/or tumors in warm-blooded animals.
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- Improved Synthesis of chlamydocin: Cyclization Studies of Tetrapeptides Containing Five α-Substituents
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A complete search for the optimal conditions for preparing cycling tetrapeptide 2 was carried out.In this study all four possible sequences of the linear tetrapeptide precursors were synthesized and cyclized.The results establish that one linear sequence is especially favorable for synthesizing the peptide ring system in chlamydocin (1).
- Pastuszak, Jacek,Gardner, Joseph H.,Singh, Jasbir,Rich, Daniel H.
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p. 2982 - 2987
(2007/10/02)
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- Anti-ulcer polypeptides containing L-aspartic acid and intermediates thereto
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This invention encompasses novel tetrapeptide amides and their intermediates containing an L-aspartic acid residue. These peptides are inhibitors of gastric acid secretion and therefore useful in the treatment of ulcers.
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- N-chloro-amino acid derivatives activity
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There is provided, a novel class of compounds exhibiting antibacterial activity, said compounds having the formula: EQU1 wherein X and Y each represent a member which may be the same or different selected from the group consisting of H and Cl with the pri
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