- Syntheses of Enantiopure 1,2-Ethylenediamines with Tethered Secondary Amines of the Formula H 2NCH 2CH[(CH 2) nNHMe]NH 2(n = 1-4) from α-Amino Acids: New Agents for Asymmetric Catalysis
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Tris(hydrochloride) adducts of the title compounds-are prepared from the inexpensive α-amino acids H 2 N(C=O)CH 2 CH(NH 2)CO 2 H, HO(C=O)(CH 2) n ′ CH(NH 2)CO 2 H (n ′ = 1, 2), and H2 N(CH 2) 4 CH(NH 2)CO 2 H, respectively (steps/overall yield = 5/32, 7/30, 7/33, 5/38). The NH 2 group that is remote from the secondary amine is installed via BH 3 reduction of an amide [-(C=O)NR 2[ derived?-from an α-amino carboxylic acid. The MeNHCH 2 units are introduced by BH 3 reductions of alkyl carbamate [RO(C=O)NHCH 2-; R = Et, t-Bu] or amide [MeHN(C=O)-] moieties.
- Kabes, Connor Q.,Gunn, Jack H.,Selbst, Maximilian A.,Lucas, Reagan F.,Gladysz, John A.
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p. 3277 - 3285
(2020/11/02)
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- Studies on the constituents of Helleborus purpurascens: use of derivatives from calix[6]arene, homooxacalix[3]arene and homoazacalix[3]arene as extractant agents for amino acids from the aqueous extract
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The task of this work was to investigate the extraction capacity of various calixarenes for free and esterified amino acids from aqueous acid phases. Furthermore, this method was applied to aqueous extracts of Helleborus purpurascens. Generally, it is known that calixarenes can be used as extractants for ammonium compounds due to π-cation and lone pair cation interactions. As first, tert-Butyl-calix[6]arene and derivatives thereof were used. They had already proven their worth in previous investigations. In addition, tert-Butyl-hexahomooxa-calix[3]arene was used also, which can also enter into lone pair cation interactions. In addition to these well-known calixarenes, new calixarenes were produced and tested. Based on the tert-Butyl-hexahomooxa-calix[3]arene, a phosphor(III)bridged derivative was prepared, combining the three aromatic hydroxyl groups to a phosphite. As a seldom-described class of calixarenes, tert-Butyl-hexahomoaza-calix[3]arene derivatives were used. The nitrogen analogues of tert-Butyl-hexahomooxa-calix[3]arene could be produced as N-benzyl derivatives. The structure of the esterified carboxymethylated derivative of N,N′,N″-Tribenzyl-tert-Butyl-hexahomoaza-calix[3]arene could be verified by X-ray structure analysis. It crystallized as a partial cone. The extraction capacity of the described calixarenes was investigated for amino acids from aqueous acidic solutions into an organic phase. For the testing were chosen asparagine, aspartic acid, tyrosine, tryptophane, phenylalanine and pipecolinic acid and their methyl esters. The amino acids and their methyl esters were dissolved in water at different pH values. The calixarenes were dissolved in dichloromethane (DCM) or chloroform. After this preparation, the aqueous acidic amino acid solutions were mixed with the solutions and shaken intensively. In addition, blank values were determined by extracting the aqueous stock solutions of the amino acids and their methyl esters with pure solvents. To determine the extraction rate, the phases were separated and each analysed using GC-FID, partially GC–MS(EI). The evaluation is performed in two ways. On the one hand the depletion in the aqueous phase and on the other hand the content in the organic phase was determined.
- Franz, M. Heiko,Iorga, Mirela,Maftei, Catalin V.,Maftei, Elena,Neda, Ion
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- Rhamnolipid inspired lipopeptides effective in preventing adhesion and biofilm formation of Candida albicans
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Rhamnolipids are biodegradable low toxic biosurfactants which exert antimicrobial and anti-biofilm properties. They have attracted much attention recently due to potential applications in areas of bioremediation, therapeutics, cosmetics and agriculture, however, the full potential of these versatile molecules is yet to be explored. Based on the facts that many naturally occurring lipopeptides are potent antimicrobials, our study aimed to explore the potential of replacing rhamnose in rhamnolipids with amino acids thus creating lipopeptides that would mimic or enhance properties of the parent molecule. This would allow not only for more economical and greener production but also, due to the availability of structurally different amino acids, facile manipulation of physico-chemical and biological properties. Our synthetic efforts produced a library of 43 lipopeptides revealing biologically more potent molecules. The structural changes significantly increased, in particular, anti-biofilm properties against Candida albicans, although surface activity of the parent molecule was almost completely abolished. Our findings show that the most active compounds are leucine derivatives of 3-hydroxy acids containing benzylic ester functionality. The SAR study demonstrated a further increase in activity with aliphatic chain elongation. The most promising lipopeptides 15, 23 and 36 at 12.5 μg/mL concentration allowed only 14.3%, 5.1% and 11.2% of biofilm formation, respectively after 24 h. These compounds inhibit biofilm formation by preventing adhesion of C. albicans to abiotic and biotic surfaces.
- Jovanovic, Milos,Radivojevic, Jelena,O'Connor, Kevin,Blagojevic, Stevan,Begovic, Biljana,Lukic, Vera,Nikodinovic-Runic, Jasmina,Savic, Vladimir
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supporting information
p. 209 - 217
(2019/03/23)
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- Improvement of methods for synthesizing dencichine
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The invention discloses improvement of methods for synthesizing dencichine, and belongs to the technical field of medicines and chemical engineering. The improvement has the advantages that the dencichine is white solid, hemostasis effects can be realized by the dencichine by means of shortening the blood coagulation time, the prothrombin time and the like, and accordingly the dencichine is an important medicine, but natural dencichine is low in extraction rate and has small profit spaces; the methods are effective ways for acquiring the dencichine by the aid of chemical synthesis processes and are low in cost, the dencichine can be industrially produced, the reaction cost can be reduced, and important bases can be provided to industrialization.
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-
Paragraph 0010; 0011; 0018
(2019/05/28)
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- Optimized syntheses of Fmoc azido amino acids for the preparation of azidopeptides
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The rise of CuI-catalyzed click chemistry has initiated an increased demand for azido and alkyne derivatives of amino acid as precursors for the synthesis of clicked peptides. However, the use of azido and alkyne amino acids in peptide chemistry is complicated by their high cost. For this reason, we investigated the possibility of the in-house preparation of a set of five Fmoc azido amino acids: β-azido l-alanine and d-alanine, γ-azido l-homoalanine, δ-azido l-ornithine and ω-azido l-lysine. We investigated several reaction pathways described in the literature, suggested several improvements and proposed several alternative routes for the synthesis of these compounds in high purity. Here, we demonstrate that multigram quantities of these Fmoc azido amino acids can be prepared within a week or two and at user-friendly costs. We also incorporated these azido amino acids into several model tripeptides, and we observed the formation of a new elimination product of the azido moiety upon conditions of prolonged couplings with 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate/DIPEA. We hope that our detailed synthetic protocols will inspire some peptide chemists to prepare these Fmoc azido acids in their laboratories and will assist them in avoiding the too extensive costs of azidopeptide syntheses. Experimental procedures and/or analytical data for compounds 3–5, 20, 25, 26, 30 and 43–47 are provided in the supporting information.
- Pícha, Jan,Budě?ínsky, Milo?,Machá?ková, Kate?ina,Collinsová, Michaela,Jirá?ek, Ji?í
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p. 202 - 214
(2017/04/06)
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- Substrate specificity of an actively assembling amyloid catalyst
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In the presence of Zn2+, the catalytic, amyloid-forming peptide Ac-IHIHIQI-NH2, was found to exhibit enhanced selectivity for hydrophobic p-nitrophenyl ester substrates while in the process of self-assembly. As opposed to the substrate p-nitrophenyl acetate, which was more effectively hydrolyzed with Ac-IHIHIQI-NH2 in its fully fibrillar state, the hydrophobic substrate Z-L-Phe-ONp was converted with a second-order rate constant more than 11-times greater when the catalyst was actively assembling. Under such conditions, Z-L-Phe-ONp hydrolysis proceeded at a greater velocity than the more hydrophilic and otherwise more labile ester Boc-L-Asn-ONp. When assembling, the catalyst also showed increased selectivity for the L-enantiomer of Z-Phe-ONp. These findings suggest the occurrence of increased interactions of hydrophobic moieties of the substrate with exposed hydrophobic surfaces of the assembling peptides and present valuable features for future de novo design consideration.
- Heier, Jason L.,Mikolajczak, Dorian J.,B?ttcher, Christoph,Koksch, Beate
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- A BOC - L - the preparation method of the asparagine (by machine translation)
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The invention discloses a BOC - L - asparagine of the preparation method, in order to L - asparagine and di-T-n-butyl as raw materials, water as a reaction solvent, in pH 9 - 10 under alkaline conditions generated by the reaction of BOC - L - asparagine, reaction solution acidified to pH 4.0 - 4.5 precipitated BOC - L - asparagine crude, is filtered, washing, drying to obtain the BOC - L - asparagine works. The invention preparation BOC - L - asparagine method has mild reaction conditions, the reaction fast, raw material cost is low, water as a reaction solvent, the follow-up operation is simple, only need to acidify it can separate out BOC - L - asparagine crystal, is favorable to the industrial production, environmental protection, safety coefficient is also relatively high. (by machine translation)
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-
Paragraph 024; 0025; 0026; 0027
(2017/02/17)
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- Comparative metabolomics and structural characterizations illuminate colibactin pathway-dependent small molecules
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The gene cluster responsible for synthesis of the unknown molecule colibactin has been identified in mutualistic and pathogenic Escherichia coli. The pathway endows its producer with a long-term persistence phenotype in the human bowel, a probiotic activity used in the treatment of ulcerative colitis, and a carcinogenic activity under host inflammatory conditions. To date, functional small molecules from this pathway have not been reported. Here we implemented a comparative metabolomics and targeted structural network analyses approach to identify a catalog of small molecules dependent on the colibactin pathway from the meningitis isolate E. coli IHE3034 and the probiotic E. coli Nissle 1917. The structures of 10 pathway-dependent small molecules are proposed based on structural characterizations and network relationships. The network will provide a roadmap for the structural and functional elucidation of a variety of other small molecules encoded by the pathway. From the characterized small molecule set, in vitro bacterial growth inhibitory and mammalian CNS receptor antagonist activities are presented.
- Vizcaino, Maria I.,Engel, Philipp,Trautman, Eric,Crawford, Jason M.
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supporting information
p. 9244 - 9247
(2014/07/21)
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- Heating reactions of N-t-Butyloxycarbonyl-Asparagine and related compounds
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N-t-Butyloxycarbonyl-amino acids (Boc-) are labile on heating to afford free amino acids, but Boc-aspartic acid gives a kind of polypeptide. This chemical feature of Boc-aspartic acid may be caused by dehydration between two carboxyl groups as well as the formation of a free amino group. Boc-Asparagine may have a similar reactivity to Boc-aspartic acid. This research describes polypeptide formation by heating Boc-asparagine and its isomer Boc-aspartic acid amide.
- Munegumi,Akao,Kawatu,Yamada,Harada
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p. 6541 - 6548
(2015/02/19)
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- Amino acid conjugates of lithocholic acid as antagonists of the EphA2 receptor
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The Eph receptor-ephrin system is an emerging target for the development of novel antiangiogenetic agents. We recently identified lithocholic acid (LCA) as a small molecule able to block EphA2-dependent signals in cancer cells, suggesting that its (5β)-cholan-24-oic acid scaffold can be used as a template to design a new generation of improved EphA2 antagonists. Here, we report the design and synthesis of an extended set of LCA derivatives obtained by conjugation of its carboxyl group with different α-amino acids. Structure-activity relationships indicate that the presence of a lipophilic amino acid side chain is fundamental to achieve good potencies. The l-Trp derivative (20, PCM126) was the most potent antagonist of the series disrupting EphA2-ephrinA1 interaction and blocking EphA2 phosphorylation in prostate cancer cells at low μM concentrations, thus being significantly more potent than LCA. Compound 20 is among the most potent small-molecule antagonists of the EphA2 receptor.
- Incerti, Matteo,Tognolini, Massimiliano,Russo, Simonetta,Pala, Daniele,Giorgio, Carmine,Hassan-Mohamed, Iftiin,Noberini, Roberta,Pasquale, Elena B.,Vicini, Paola,Piersanti, Silvia,Rivara, Silvia,Barocelli, Elisabetta,Mor, Marco,Lodola, Alessio
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supporting information
p. 2936 - 2947
(2013/05/22)
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- Design, synthesis and primary activity of thiomorpholine derivatives as DPP-IV inhibitors
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Thirteen thiomorpholine-bearing compounds were designed and synthesized as dipeptidyl peptidase IV (DPP-IV) inhibitors, with natural and non-natural l-amino acids as the starting materials. Their structures were characterized by 1H NMR, 13C NMR and HR-MS. The target compounds were screened for the DPP-IV inhibition, and the preliminary SAR result was obtained. Particularly, compounds 4c, 4d and 4f with good DPP-IV inhibition in vitro were further evaluated through a mouse oral glucose tolerance test (OGTT). The preliminary result showed the potential value for further studies on those thiomorpholine-bearing compounds as DPP-IV inhibitors.
- Han, Bei,Liu, Jing Long,Huan, Yi,Li, Peng,Wu, Qi,Lin, Zi Yun,Shen, Zhu Fang,Yin, Da Li,Huang, Hai Hong
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scheme or table
p. 297 - 300
(2012/05/20)
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- Kinase inhibitor compounds
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The invention relates to compounds, compositions comprising the compounds, and methods of using the compounds and compound compositions. The compounds, compositions, and methods described herein can be used for the therapeutic modulation of kinase-mediated processes, and treatment of disease and disease symptoms, particularly those mediated by certain kinase enzymes.
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Page/Page column 44
(2009/04/24)
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- KINASE INHIBITOR COMPOUNDS
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The invention relates to compounds, compositions comprising the compounds, and methods of using the compounds and compound compositions. The compounds, compositions, and methods described herein can be used for the therapeutic modulation of kinase-mediated processes, and treatment of disease and disease symptoms, particularly those mediated by certain kinase enzymes.
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Page/Page column 86
(2008/06/13)
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- Mapping the landscape of potentially primordial informational oligomers: Oligodipeptides and oligodipeptoids tagged with triazines as recognition elements
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(Chemical Equation Presented) Pairing up: Oligodipeptide, oligodeoxy-dipeptide, or oligodipeptoid backbones tagged with the 2,4-diaminotriazine nucleus pair strongly with complementary DNA and RNA. This is in sharp contrast with the behavior of the 2,4-dioxotriazine nucleus, which does not act as a nucleo-base in these systems.
- Mittapalli, Gopi Kumar,Reddy, Kondreddi Ravinder,Xiong, Hui,Munoz, Omar,Han, Bo,De Riccardis, Francesco,Krishnamurthy, Ramanarayanan,Eschenmoser, Albert
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p. 2470 - 2477
(2008/03/11)
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- Proteasome inhibitors and methods of using the same
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The present invention provides boronic acid compounds, boronic esters, and compositions thereof that can modulate apoptosis such as by inhibition of proteasome activity. The compounds and compositions can be used in methods of inducing apoptosis and treating diseases such as cancer and other disorders associated directly or indirectly with proteasome activity.
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Page/Page column 38
(2008/06/13)
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- The 5-substituted piperazine as a novel secondary pharmacophore greatly improving the physical properties of urea-based inhibitors of soluble epoxide hydrolase
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The inhibition of the mammalian soluble epoxide hydrolase (sEH) is a promising new therapy in the treatment of hypertention and inflammation. The problems of limited water solubility and high melting points commonly displayed by the active 1,3-disubstituted ureas prevent the further development of potent urea-based sEH inhibitors. Therefore, a new class of potent inhibitors of sEH were designed and synthesized by the introduction of a polar constrained piperazino group in the right side of adasmantyl urea to increase the water solubility. A facile and general synthesis was established to prepare a series of 1-adamantan-1-yl-3-(2-piperazin-2-yl-ethyl)-ureas (1a-d) with various 5-substitutions on the 2-piperazino ring, which will advance the SAR study by the efficient making of structurally diverse analogs. The effect of the 5-substitution on the activity and the water solubility was examined. The best potency was exhibited by the 5-benzyl-substituted-piperazine-containing urea with an IC50 value of 1.37 μM against human sEH and good water solubility (S = 7.46 mg/mL) and low melting point, in which the 5-substituted piperazine serves as a favorable secondary pharmacophore and a water-solubility enhancing group. Our present work provides a promising new template for the design of orally available therapeutic agents for the disorders that can be addressed by changing the in vivo concentration of the chemical mediators that contain an epoxide.
- Li, Hui-Yuan,Jin, Yi,Morisseau, Christophe,Hammock, Bruce D.,Long, Ya-Qiu
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p. 6586 - 6592
(2007/10/03)
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- PROTEASOME INHIBITORS AND METHODS OF USING THE SAME
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The present invention provides boronic acid compounds, boronic esters, and compositions thereof that can modulate apoptosis such as by inhibition of proteasome activity. The compounds and compositions can be used in methods of inducing apoptosis and treating diseases such as cancer and other disorders associated directly of indirectly with proteasome activity.
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Page/Page column 214
(2008/06/13)
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- A novel and efficient method for cleavage of phenacylesters by magnesium reduction with acetic acid
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(Equation Presented) In the present study, we use magnesium turnings as a new deprotection reagent for the phenacyl group during orthogonal organic synthesis in the presence of other esters and sensitive protecting groups. By applying the new magnesium turnings/acetic acid deprotection method, phenacyl group can be more easily combined with other protecting groups that are not compatible with the zinc/acetic acid method.
- Kokinaki, Stella,Leondiadis, Leondios,Ferderigos, Nikolas
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p. 1723 - 1724
(2007/10/03)
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- Design, synthesis and biological evaluation of nonpeptide integrin antagonists
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Recent studies demonstrated that peptide and antibody antagonists of integrin α(v)β3 block angiogenesis and tumor growth. In this article, the design, synthesis and biological evaluation of a series of nitroaryl ether-based, nonpeptide mimetics are described. The design of these compounds was based on Merck's arylether/α-aminoacid/guanidine framework and incorporates a novel nitroaryl system. The synthesized mimetics were tested against a variety of integrins (α(v)β3, α(IIb)β3, and α(v)β5) in order to determine their binding selectivity and ability to inhibit cell adhesion. Selected compounds were also tested for their ability to inhibit angiogenesis in vivo in the CAM (chick chorioallantoic membrane) assay. From the generated compound library, compounds 16 and 19 proved to be potent and selective inhibitors of α(IIb)β3 (IC50=14nM) whereas compound 11 showed excellent in vivo inhibition of angiogenesis (at 30μg/embryo). Copyright (C) 1998 Elsevier Science Ltd.
- Nicolaou,Trujillo, John I.,Jandeleit, Bernd,Chibale, Kelly,Rosenfeld,Diefenbach,Cheresh,Goodman
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p. 1185 - 1208
(2007/10/03)
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- Cyclic peptides and use thereof
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Cyclic peptides and their salts have antagonistic activity on endothelin receptors and antagonistic activity on NK2 receptors. The peptides have the formula STR1 wherein X and Y each represent α-amino acid residues, A represents a D-acidic-α-amino acid residue, B represents a neutral α-amino acid residue, C represents an L-α-amino acid residue and D represents a D-α-amino acid residue having an aromatic ring group; wherein hydroxy, thiol, amino, imino and carboxyl groups can be substituted or unsubstituted. Pharmaceutical compositions containing such peptides are also described.
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- Monoclonal antibody against an acidic FGF protein and hybridoma for its production
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The present invention provides a hybrid cell line producing monoclonal antibody to an acidic fibroblast growth factor (aFGF) protein. The hybridoma is established by fusing spleen cells from immunized mice with myeloma cells. The hybridomas are cultured as clones, and antibodies obtained from the individual clones are tested for their specificity for aFGF protein. Antibodies can be obtained from the culture growth medium or from ascitic fluid of mice bearing the hybridoma tumor. Diagnostic and therapeutic uses of the monoclonal antibody are also disclosed.
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- NEW PENICILLINS FROM ISOPENICILLIN N SYNTHASE.
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The three tripeptides δ-L-α-aminoadipoyl-L-cysteinyl-D-propargylglycine, δ-L-α-aminoadipoyl-L-cysteinyl-D-cyanoalanine and δ-L-α-aminoadipoyl-L-cysteinyl-D--norvaline were synthesised and incubated with the enzyme Isopenicillin N Synthase (IPNS).All incubation mixtures contained biologically active products, and led to the isolation of four new penicillins (β-ethyl, α-acetylenic, α- and β-nitrile) following purification by reverse phase HPLC.The stereochemistries of formation of monosubstituted penicillins with IPNS are rationalised.
- Baldwin, Jack E.,Bradley, Mark,Abbott, Shaun D.,Adlington, Robert M.
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p. 5309 - 5328
(2007/10/02)
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- HIV related peptides
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Fragments of HIV p17 protein ranging in length from about 12 to abut 40 amino acids are used to form diagnostics and vaccines for detection or treatment of AIDS. Specific peptide fragments extend from the N-terminal to the C-terminal. Peptides having the amino acid sequences shown by the following formula (I), (II), (III), (IV) and (V):, Tyr-Ser-Val-His-Gln-Arg-Ile-Asp-Val-Lys--Asp-Thr-Lys-Glu-Ala-Leu-Gly-Lys-Ile-Glu--Glu-Glu-Gln-Asn-Lys-Ser-Lys-Lys-Lys-Ala (I), Gly-Ala-Arg-Ala-Ser-Val-Leu-Ser-Gly-Gly--Glu-Leu-Asp-Arg-Trp-Glu-Lys-Ile-Arg-Leu--Arg-Pro-Gly-Gly-Lys-Lys-Lys-Tyr-Lys-Leu--Lys-His (II), Ile-Val-Trp-Ala-Ser-Arg-Glu-Leu-Glu-Arg--Phe-Ala-Val-Asn-Pro-Gly-Leu-Leu (III), Glu-Thr-Ser-Glu-Gly-Cys-Arg-Gln-Ile-Leu--Gly-Gln-Leu-Gln-Pro-Ser-Leu-Gln-Thr-Gly--Ser-Glu-Glu-Leu-Arg-Ser-Leu-Tyr-Asn-Thr--Val-Ala-Thr-Leu (IV), Ala-Gln-Gln-Ala-Ala-Ala-Asp-Thr-Gly-His--Ser-Ser-Gln-Val-Ser-Gln-Asn-Tyr (V), are immunoreactive to antibodies in sera of patients testing seropositive for p17 of HIV-1.
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-
- Enantioselectivity in Chiral Inverted Micelles and Co-surfactant Localization in Microemulsion
-
The enantioselectivity observed in a study of the imidazole-catalysed hydrolysis of enantiomeric pairs of three amino acids in chiral reversed micelles proves that the reaction takes place in the micelle membrane.
- Andriamanampisoa, Ramarofidy,Boyer, Bernard,Lamaty, Gerard,Roque, Jean Pierre
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p. 597 - 598
(2007/10/02)
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- Synthesis of a putative subtype specific antigenic heptapeptide from Escherichia coli K88 ad protein fimbriae.
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The heptapeptide methyl ester Phe-Asn-Glu-Asn-Met-Ala-Tyr-OMe covering the amino acid sequence of the region 213-219 of Escherichia Coli K88 ad protein fimbriae is synthesized using N alpha-t-butyloxycarbonyl-protection and benzyl groups for side-chain-protection. All condensation reactions are performed in 84-97% yield by preactivation of the protected amino acids by dicyclohexylcarbodiimide (DCC) and 1-hydroxybenzotriazole (HOBt), and reaction of the resulting active ester with amine in the presence of 4-methylmorpholine (NMM). A mechanism is proposed for the nitrile formation in the side-chain of activated asparagine, and the suppression of this side-reaction is investigated. The repetitive deprotection is performed in a mixture of trifluoroacetic acid (TFA), phenol and p-cresol to give the TFA salts in virtually quantitatively yields. The final deprotection of the heptapeptide is carried out in a mixture of 25% hydrogen fluoride (HF) and dimethyl sulfide (DMS) in an overall yield of 48%. The serological and conformational properties of the synthetic peptide are under investigation.
- Meldal
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p. 242 - 249
(2007/10/02)
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- PROPERTIES OF Nα,Nca-DI-TERT-BUTYLOXYCARBONYL-ω-CARBAMOYL-α-AMINO ACIDS AND DIRECT SYNTHESIS OF PROTECTED HOMOGLUTAMIC ACID DERIVATIVES
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The protected carboxamide function of Nα,Nca-di-tert-butyloxy-carbonyl-ω-carbamoyl-α-amino acids worked well with nucleophilic reagents.Applying this novel reactivity, we developed an efficient synthetic route to Nα-tert-butyloxycarbonylhomoglutamic acid and its derivatives, including Nα-tert-butyloxycarbonylhomoglutamic acid δ-benzyl ester, from Nα,Nca-di-tert-butyloxycarbonylhomoglutamine.KEYWORDS - protected homoglutamic acid synthesis; Nca-tert-butyloxycarbonylated carboxamide; hydrolysis; selective deprotection; Nα-tert-butyloxycarbonylhomoglutamic acid δ-benzyl ester; Nα-tert-butyloxycarbonylhomoglutamic acid α-tert-butyl ester; Nα-tert-butyloxycarbonylhomoglutamine; optical purity
- Sakura, Naoki,Hirose, Kyoko,Hashimoto, Tadashi
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p. 3506 - 3509
(2007/10/02)
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- Untriakontapeptide with opiate activity
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An untriakontapeptide having significant opiate agonist activity has been isolated from camel pituitary glands. The structure of this peptide has been determined and this peptide was then synthesized utilizing solid phase peptide synthesis. Both natural and synthetic material show identical physical and biological properties.
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