- Diastereoselectivity in the alkylation of 4-fluoroproline methyl esters
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The reaction of alkylation of cis- and trans-4-fluoro-N-Boc-l-proline methyl esters has been examined by exposing their lithium enolates to a range of alkylating agents. The process showed a high degree of facial diastereoselectivity (except when methyl iodide was used as alkylating agent), invariably giving rise to products bearing the alkyl group in anti with respect to the fluorine atom. A tentative model to account for the observed stereoselectivity is also proposed.
- Filosa, Rosanna,Holder, Claude,Auberson, Yves P.
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- 4R- and 4S-iodophenyl hydroxyproline, 4R-pentynoyl hydroxyproline, and S-propargyl-4-thiolphenylalanine: Conformationally biased and tunable amino acids for bioorthogonal reactions
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Bioorthogonal reactions allow the introduction of new functionalities into peptides, proteins, and other biological molecules. The most readily accessible amino acids for bioorthogonal reactions have modest conformational preferences or bases for molecular interactions. Herein we describe the synthesis of 4 novel amino acids containing functional groups for bioorthogonal reactions. (2S,4R)- and (2S,4S)-iodophenyl ethers of hydroxyproline are capable of modification via rapid, specific Suzuki and Sonogashira reactions in water. The synthesis of these amino acids, as Boc-, Fmoc- and free amino acids, was achieved through succinct sequences. These amino acids exhibit well-defined conformational preferences, with the 4S-iodophenyl hydroxyproline crystallographically exhibiting β-turn (φ, ψ ~ -80°, 0°) or relatively extended (φ, ψ ~ -80°, +170°) conformations, while the 4R-diastereomer prefers a more compact conformation (φ ~ -60°). The aryloxyproline diastereomers present the aryl groups in a highly divergent manner, suggesting their stereospecific use in molecular design, medicinal chemistry, and catalysis. Thus, the 4R- and 4S-iodophenyl hydroxyprolines can be differentially applied in distinct structural contexts. The pentynoate ester of 4R-hydroxyproline introduces an alkyne functional group within an amino acid that prefers compact conformations. The propargyl thioether of 4-thiolphenylalanine was synthesized via copper-mediated cross-coupling reaction of thioacetic acid with protected 4-iodophenylalanine, followed by thiolysis and alkylation. This amino acid combines an alkyne functional group with an aromatic amino acid and the ability to tune aromatic and side chain properties via sulfur oxidation. These amino acids provide novel loci for peptide functionalization, with greater control of conformation possible than with other amino acids containing these functional groups.
- Forbes, Christina R.,Pandey, Anil K.,Ganguly, Himal K.,Yap, Glenn P. A.,Zondlo, Neal J.
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- Total Synthesis and Stereochemical Revision of the 2-Formylpyrrole Alkaloid Hemerocallisamine i
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The first total synthesis of the 2-formylpyrrole alkaloid hemerocallisamine I is reported. The convergent synthesis features a key Maillard-Type condensation of a complex amine derived from cis-4-hydroxy-l-proline with a dihydropyranone, to directly furnish the 2-formylpyrrole ring system. The absolute configuration of hemerocallisamine I has been revised on the basis of optical rotation data obtained for the synthesized compound.
- Wood, James M.,Furkert, Daniel P.,Brimble, Margaret A.
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- Selective l-nitroargininylaminopyrrolidine and l-nitroargininylaminopiperidine neuronal nitric oxide synthase inhibitors
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Selective inhibition of the localized excess production of NO by neuronal nitric oxide synthase (nNOS) has been targeted as a potential means of treating various neurological disorders. Based on observations from the X-ray crystal structures of complexes of nNOS with two nNOS-selective inhibitors, (4S)-N-{4-amino-5-[(2-amino)ethylamino]pentyl}-N′-nitroguanidine (l-Arg(NO2)-l-Dbu-NH2 (1) and 4-N-(Nω-nitro-l-argininyl)-trans-4-amino-l-proline amide (2), a series of descarboxamide analogues was designed and synthesized (3-7). The most potent compound was aminopyrrolidine analogue 3, which exhibited better potency and selectivity for nNOS than parent compound 2. In addition, 3 provided higher lipophilicity and a lower molecular weight than 2, therefore having better physicochemical properties. Nα-Methylated analogues (8-11) also were prepared for increased lipophilicity of the inhibitors, but they had 4- to 5-fold weaker binding affinity compared to their parent compounds.
- Seo, Jiwon,Martasek, Pavel,Roman, Linda J.,Silverman, Richard B.
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- Altering the sex pheromone cyclo(L-pro-l-pro) of the diatom seminavis robusta towards a chemical probe
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As a major group of algae, diatoms are responsible for a substantial part of the primary production on the planet. Pennate diatoms have a predominantly benthic lifestyle and are the most species-rich diatom group, with members of the raphid clades being motile and generally having heterothallic sexual reproduction. It was recently shown that the model species Seminavis robusta uses multiple sexual cues during mating, including cyclo(L-Pro-L-Pro) as an attraction pheromone. Elaboration of the pheromone-detection system is a key aspect in elucidating pennate diatom life-cycle regulation that could yield novel fundamental insights into diatom speciation. This study reports the synthesis and bio-evaluation of seven novel pheromone analogs containing small structural alterations to the cyclo(L-Pro-L-Pro) pheromone. Toxicity, attraction, and interference assays were applied to assess their potential activity as a pheromone. Most of our analogs show a moderate-to-good bioactivity and low-to-no phytotoxicity. The pheromone activity of azide-and diazirine-containing analogs was unaffected and induced a similar mating behavior as the natural pheromone. These results demonstrate that the introduction of confined structural modifications can be used to develop a chemical probe based on the diazirine-and/or azide-containing analogs to study the pheromone-detection system of S. robusta.
- Bonneure, Eli,De Baets, Amber,De Decker, Sam,Van den Berge, Koen,Clement, Lieven,Vyverman, Wim,Mangelinckx, Sven
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- Multipodal insulin mimetics built on adamantane or proline scaffolds
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Multi-orthogonal molecular scaffolds can be applied as core structures of bioactive compounds. Here, we prepared four tri-orthogonal scaffolds based on adamantane or proline skeletons. The scaffolds were used for the solid-phase synthesis of model insulin mimetics bearing two different peptides on the scaffolds. We found that adamantane-derived compounds bind to the insulin receptor more effectively (Kd value of 0.5 μM) than proline-derived compounds (Kd values of 15–38 μM) bearing the same peptides. Molecular dynamics simulations suggest that spacers between peptides and central scaffolds can provide greater flexibility that can contribute to increased binding affinity. Molecular modeling showed possible binding modes of mimetics to the insulin receptor. Our data show that the structure of the central scaffold and flexibility of attached peptides in this type of compound are important and that different scaffolds should be considered when designing peptide hormone mimetics.
- Hajduch, Jan,Fabre, Benjamin,Klopp, Benjamin,Pohl, Radek,Budě?ínsky, Milo?,?olínová, Veronika,Ka?i?ka, Václav,K?prülüoglu, Cemal,Eyrilmez, Saltuk Mustafa,Lep?ík, Martin,Hobza, Pavel,Mitrová, Katarína,Lubos, Marta,Hernández, María Soledad Garre,Jirá?ek, Ji?í
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- Cross-Linked Collagen Triple Helices by Oxime Ligation
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Covalent cross-links are crucial for the folding and stability of triple-helical collagen, the most abundant protein in nature. Cross-linking is also an attractive strategy for the development of synthetic collagen-based biocompatible materials. Nature uses interchain disulfide bridges to stabilize collagen trimers. However, their implementation into synthetic collagen is difficult and requires the replacement of the canonical amino acids (4R)-hydroxyproline and proline by cysteine or homocysteine, which reduces the preorganization and thereby stability of collagen triple helices. We therefore explored alternative covalent cross-links that allow for connecting triple-helical collagen via proline residues. Here, we present collagen model peptides that are cross-linked by oxime bonds between 4-aminooxyproline (Aop) and 4-oxoacetamidoproline placed in coplanar Xaa and Yaa positions of neighboring strands. The covalently connected strands folded into hyperstable collagen triple helices (Tm 80 °C). The design of the cross-links was guided by an analysis of the conformational properties of Aop, studies on the stability and functionalization of Aop-containing collagen triple helices, and molecular dynamics simulations. The studies also show that the aminooxy group exerts a stereoelectronic effect comparable to fluorine and introduce oxime ligation as a tool for the functionalization of synthetic collagen.
- Hentzen, Nina B.,Smeenk, Linde E. J.,Witek, Jagna,Riniker, Sereina,Wennemers, Helma
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- Short, highly efficient syntheses of protected 3-azido- and 4-azidoproline and their precursors
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matrix presented An improved synthesis of protected cis- and trans-3-azido-L-proline and cis- and frans-4-azido-L- and -D-proline is reported. These compounds have been synthesized from the corresponding hydroxyproline precursors using diphenylphosphoryl azide under Mitsunobu conditions. Short, highly efficient syntheses of these precursors are described, based on a new lactone-opening reaction and p-nitrobenzoate hydrolysis under very mild conditions.
- Gomez-Vidal, Jose A.,Silverman, Richard B.
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- (2 S,4 R)- and (2 S,4 S)-Perfluoro- tert -butyl 4-hydroxyproline: Two conformationally distinct proline amino acids for sensitive application in 19F NMR
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(2S,4R)- and (2S,4S)-perfluoro-tert-butyl 4-hydroxyproline were synthesized (as Fmoc-, Boc-, and free amino acids) in 2-5 steps. The key step of each synthesis was a Mitsunobu reaction with perfluoro-tert-butanol, which incorporated a perfluoro-tert-butyl group, with nine chemically equivalent fluorines. Both amino acids were incorporated in model α-helical and polyproline helix peptides. Each amino acid exhibited distinct conformational preferences, with (2S,4R)-perfluoro-tert-butyl 4-hydroxyproline promoting polyproline helix. Peptides containing these amino acids were sensitively detected by 19F NMR, suggesting their use in probes and medicinal chemistry.
- Tressler, Caitlin M.,Zondlo, Neal J.
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- Design, Synthesis, and Biochemical Evaluation of Alpha-Amanitin Derivatives Containing Analogs of the trans-Hydroxyproline Residue for Potential Use in Antibody-Drug Conjugates
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Alpha-amanitin, an extremely toxic bicyclic octapeptide extracted from the death-cap mushroom, Amanita phalloides, is a highly selective allosteric inhibitor of RNA polymerase II. Following on growing interest in using this toxin as a payload in antibody-drug conjugates, herein we report the synthesis and biochemical evaluation of several new derivatives of this toxin to probe the role of the trans-hydroxyproline (Hyp), which is known to be critical for toxicity. This structure activity relationship (SAR) study represents the first of its kind to use various Hyp-analogs to alter the conformational and H-bonding properties of Hyp in amanitin.
- Braun, Alexandra,Gallo, Francesca,Hambira, Chido M.,Hechler, Torsten,Kato, Brandon,Müller, Christoph,Matinkhoo, Kaveh,Pahl, Andreas,Perrin, David M.,Wei, Charlie,Wong, Antonio A. W. L.
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p. 10282 - 10292
(2021/06/25)
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- Synthesis process of N-BOC-cis-4-hydroxyproline methyl ester
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The invention discloses a synthesis process of N-BOC-cis-4-hydroxyproline methyl ester. The synthesis process comprises the following steps: (1) adding raw materials including dichloromethane, 4-hydroxy-L-proline and DMAP into a 2 L reaction flask, stirring, slowly dropwise adding BOC anhydride into the reaction liquid, after dropwise adding, sampling, carrying out TLC, completely reacting the rawmaterials, adding water into the reaction liquid after treatment, stirring at a temperature of 20-30 DEG C, separating the liquid, drying an organic phase by using anhydrous sodium sulfate, and concentrating under reduced pressure to obtain a white solid product; and (2) taking the obtained product, adding tetrahydrofuran and DCC into a 5 L reaction flask, stirring at 20-30 DEG C to react for 1 hour, dropwise adding methanol into the reaction solution, keeping the temperature after dropwise adding, sampling, carrying out TLC until the reaction is complete, filtering the reaction solution, collecting the filtrate, concentrating under reduced pressure until no liquid flows out to obtain a white solid crude product, heating, collecting the filtrate, collecting a filter cake, and drying the filter cake to obtain a white solid. According to the invention, the product is prepared with high quality and high yield.
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Paragraph 0021-0023
(2021/01/20)
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- Substituted Quinazoline and Pyridopyrimidine Derivatives Useful as Anticancer Agents
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Compounds of the general formula: processes for the preparation of these compounds, compositions containing these compounds, and the uses of these compounds.
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Paragraph 0465; 0466
(2019/08/22)
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- As Aurora kinase inhibitor derivatives
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The present invention relates to a substituted pyrazole derivative used for inhibiting Aurora kinase and represented by formula (I) or formula (Ia), or stereo isomers, geometric isomers, tautomers, nitrogen oxides, hydrates, solvates, metabolites, esters, pharmaceutically acceptable salts or prodrugs thereof, a medicinal composition containing the above compounds as active ingredients, and a use of the compounds and the medicinal composition in preparation of medicines for protecting, processing, treating or mitigating proliferative diseases of patients.
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Paragraph 0572; 0577; 0578
(2019/06/27)
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- Synthesis and antibacterial activity of 6(R)- and 6(S)-fluoropenibruguieramine As: Fluorine as a probe for testing the powerfulness of memory of chirality (MOC)
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The synthesis of 6(R)- and 6(S)- fluoropenibruguieramine As has been achieved, employing the elegant strategy developed by Kim and co-workers. Single diastereomers were formed via the key intramolecular aldol reaction, and both of the products were unambiguously confirmed by X-ray diffraction crystallography. This reaction shows that the fluorine amide effect could not compete with the memory of chirality (MOC) effect, thus further demonstrating the powerfulness of MOC effect in asymmetric synthesis. The biological testing carried out in this work indicates that the principal of antibacterial activity of the natural extract is probably not penibruguieramine A.
- Liu, Ting,Yan, Nan,Zhao, Hui,Wang, Zhen-Xing,Hu, Xiang-Guo
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- COMPOSITIONS AND METHODS FOR TREATING AND PREVENTING NEURODEGENERATIVE DISORDERS
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Compounds, pharmaceutical compositions, methods and kits are described for treating or preventing neurodegenerative diseases such as Alzheimer's disease.
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Page/Page column 158; 159; 160
(2017/03/08)
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- Synthesis of (1R,4R)-2,5-diazabicyclo[2.2.1]heptane derivatives by an epimerization-lactamization cascade reaction
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An epimerization-lactamization cascade of functionalized (2S,4R)-4-aminoproline methyl esters is developed and applied in synthesizing (1R,4R)-2,5-diazabicyclo[2.2.1]heptane (DBH) derivatives. (2S,4R)-4-Aminoproline methyl esters are likely to undergo 2-epimerization under basic conditions, followed by an intramolecular aminolysis of the (2R)-epimer to form the bridged lactam intermediates. Key factors identified for this cascade reaction include the electron-withdrawal N-protective group in the substrates and a strong base as the promoter.
- Cui, Benqiang,Yu, Jie,Yu, Fu-Chao,Li, Ya-Min,Chang, Kwen-Jen,Shen, Yuehai
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p. 10386 - 10392
(2015/01/30)
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- Process for making a 4-amino-4-oxobutanoyl peptide cyclic analogue, an inhibitor of viral replication, and intermediates thereof
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The invention provides a process of preparing 4-amino-4-oxobutanoyl peptides and cyclic analogues thereof of Compound I and pharmaceutically acceptable salts thereof.
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Page/Page column 9; 27
(2015/04/21)
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- NOVEL AMINO PYRIMIDINE DERIVATIVES
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The present invention describes new amino pyrimidine derivatives and pharmaceutically acceptable salts thereof which appear to interact with Bruton's tyrosine kinase (Btk). Accordingly, the novel amino pyrimidines may be effective in the treatment of autoimmune disorders, inflammatory diseases, allergic diseases, airway diseases, such as asthma and chronic obstructive pulmonary disease (COPD), transplant rejection, cancers e.g. of hematopoietic origin or solid tumors.
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- 4-Fluoro and 4-hydroxy pyrrolidine-thioxotetrahydropyrimidinones: Organocatalysts for green asymmetric transformations in brine
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The synthesis of both trans- and cis-diastereomers of pyrrolidinine-thioxotetrahydropyrimidinone bearing either a fluorine or a hydroxyl group was accomplished. The new compounds were tested for their catalytic properties in a variety of asymmetric organic transformations and compared with the first generation catalyst. It was found that the new catalysts could efficiently catalyze the reactions in brine, without the use of organic solvent, and by employing an almost stoichiometric amount of reagents. Thus, the products were isolated by simple extractions, avoiding the use of chromatography in excellent yields, diastereoselectivities, and enantioselectivities.
- Kaplaneris, Nikolaos,Koutoulogenis, Giorgos,Raftopoulou, Marianna,Kokotos, Christoforos G.
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p. 5464 - 5473
(2015/06/16)
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- NOVEL AMINO PYRIMIDINE DERIVATIVES
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The present invention describes new amino pyrimidine derivatives of formula (I) and pharmaceutically acceptable salts thereof which appear to interact with Bruton's tyrosine kinase (Btk). Accordingly, the novel amino pyrimidines may be effective in the treatment of autoimmune disorders, inflammatory diseases, allergic diseases, airway diseases, such as asthma and chronic obstructive pulmonary disease (COPD), transplant rejection, cancers e.g. of hematopoietic origin or solid tumors.
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- Accessible chiral linker to enhance potency and selectivity of neuronal nitric oxide synthase inhibitors
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The three important mammalian isozymes of nitric oxide synthase (NOS) are neuronal NOS (nNOS), endothelial NOS (eNOS), and inducible NOS (iNOS). Inhibitors of nNOS show promise as treatments for neurodegenerative diseases. Eight easily synthesized compounds containing either one (20a,b) or two (9a-d; 15a,b) 2-amino-4-methylpyridine groups with a chiral pyrrolidine linker were designed as selective nNOS inhibitors. Inhibitor 9c is the best of these compounds, having a potency of 9.7 nM and dual selectivity of 693 and 295 against eNOS and iNOS, respectively. Crystal structures of nNOS complexed with either 9a or 9c show a double-headed binding mode, where each 2-aminopyridine headgroup interacts with either a nNOS active site Glu residue or a heme propionate. In addition, the pyrrolidine nitrogen of 9c contributes additional hydrogen bonds to the heme propionate, resulting in a unique binding orientation. In contrast, the lack of hydrogen bonds from the pyrrolidine of 9a to the heme propionate allows the inhibitor to adopt two different binding orientations. Both 9a and 9c bind to eNOS in a single-headed mode, which is the structural basis for the isozyme selectivity.
- Jing, Qing,Li, Huiying,Roman, Linda J.,Martasek, Pavel,Poulos, Thomas L.,Silverman, Richard B.
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supporting information
p. 56 - 60
(2014/02/14)
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- PERFLUORO-TERT-BUTYL HYDROXYPROLINE
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The present invention provides novel analogues of alpha amino acids, comprising a perfluoro-tert-butyl group, and molecules comprising the novel analogues. Also provided are a wide range of applications of the novel analogues in therapeutics, theranostics and pharmaceuticals as well as in imaging applications. In particular, the use of the novel analogues in detecting or modifying a target molecule is provided.
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- HETEROCYCLIC COMPOUNDS AND METHODS FOR THEIR USE
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The present invention relates to heterocyclic compounds useful for antagonising angiotensin II Type 2 (AT2) receptor. More particularly the invention relates to pyrrolidine and azetidine compounds, compositions containing them and their use in methods of treating or preventing disorders or diseases associated with AT2 receptor function including neuropathic pain, inflammatory pain, conditions associated with neuronal hypersensitivity, impaired nerve conduction velocity, cell proliferation disorders, disorders associated with an imbalance between bone resorption and bone formation and disorders associated with aberrant nerve regeneration.
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Page/Page column 79; 80
(2013/07/19)
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- Design and synthesis of simplified taxol analogs based on the T-Taxol bioactive conformation
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A series of compounds designed to adopt a conformation similar to the tubulin-binding T-Taxol conformation of the anticancer drug paclitaxel has been synthesized. Both the internally bridged analogs 37-39, 41 and the open-chain analogs 27-29 and 43 were prepared. The bridged analogs 37-39 and 41 were synthesized by Grubbs' metatheses of compounds 30-32 and 33, which, in turn, were prepared by coupling β-lactams 24-26 with alcohols 22 and 23. Both the bridged and the open-chain analogs showed moderate to good cytotoxicity.
- Zhao, Jielu,Bane, Susan,Snyder, James P.,Hu, Haipeng,Mukherjee, Kamalika,Slebodnick, Carla,Kingston, David G.I.
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experimental part
p. 7664 - 7678
(2012/01/05)
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- Solid-phase synthesis of smac peptidomimetics incorporating triazoloprolines and biarylalanines
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Apoptotic induction mechanisms are of crucial importance for the general homeostasis of multicellular organisms. In cancer the apoptotic pathways are downregulated, which, at least partly, is due to an abundance of inhibitors of apoptosis proteins (IAPs) that block the apoptotic cascade by deactivating proteolytic caspases. The Smac protein has an antagonistic effect on IAPs, thus providing structural clues for the synthesis of new pro-apoptotic compounds. Herein, we report a solid-phase approach for the synthesis of Smac-derived tetrapeptide libraries. On the basis of a common (N-Me)AVPF sequence, peptides incorporating triazoloprolines and biarylalanines were synthesized by means of Cu(I)-catalyzed azide-alkyne cycloaddition and Pd-catalyzed Suzuki cross-coupling reactions. Solid-phase procedures were optimized to high efficiency, thus accessing all products in excellent crude purities and yields (both typically above 90%). The peptides were subjected to biological evaluation in a live/dead cellular assay which revealed that structural decorations on the AVPF sequence indeed are highly important for cytotoxicity toward HeLa cells.
- Le Quement, Sebastian T.,Ishoey, Mette,Petersen, Mette T.,Thastrup, Jacob,Hagel, Grith,Nielsen, Thomas E.
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p. 667 - 675
(2012/03/22)
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- Part 2: Design, synthesis and evaluation of hydroxyproline-derived α2δ ligands
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Conformational constraint has been used to design a potent series of α2δ ligands derived from the readily available starting material (2S,4R)-hydroxy-l-proline. The ligands have improved physicochemistry and potency compared to their linear counterparts (described in our earlier publication) and the lead compound has been progressed to clinical development.
- Rawson, David J.,Brugier, Delphine,Harrison, Anthony,Hough, Jo,Newman, Julie,Otterburn, Joe,Maw, Graham N.,Price, Jenny,Thompson, Lisa R.,Turnpenny, Paul,Warren, Andrew N.
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p. 3767 - 3770
(2011/08/06)
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- Novel chemotactic For-Met-Leu-Phe-OMe (fMLF-OMe) analogues based on Met residue replacement by 4-amino-proline scaffold: Synthesis and bioactivity
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cis-(2S,4S) 4-Amino-proline (cAmp) and trans-(2S,4R) 4-amino-proline (tAmp) residues, bearing N-For or N-Boc substituents at the two amino groups, have been incorporated into the potent chemotactic agent fMLF-OMe in place of the N-terminal native (S)-methionine to give the analogues 17a-19a and 17b-19b. The new ligands have been examined for their activity (chemotaxis, superoxide anion production and lysozyme release) on human neutrophils as agonists and antagonists. Compounds 19a and 19b, bearing two N-For groups at the proline scaffold, are active and selective chemoattractants. The ligand 18b, containing N-For at the 4-amino group of the N-Boc-tAmp residue, exhibits significant chemotactic antagonism. The influence of the different substitution at the N-terminal position of the new analogues is discussed.
- Torino, Domenica,Mollica, Adriano,Pinnen, Francesco,Feliciani, Federica,Spisani, Susanna,Lucente, Gino
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p. 251 - 259
(2011/03/19)
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- ANTIBACTERIAL FLUOROQUINOLONE ANALOGS
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Compounds having antibacterial activity are disclosed. The compunds have the following structure (I): including stereoisomers, pharmaceutically acceptable salts and prodrugs thereof, wherein A, B, D, E, G, R1, R2, R3, R4, R5, R6 and R7 are as defined herein. Methods associated with preparation and use of such compounds, as well as pharmaceutical compositions comprising such compounds, are also disclosed.
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Page/Page column 253-254
(2010/01/29)
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- Highly enantioselective Michael addition reactions in water catalyzed by an insoluble MPS-supported 4-sulfonamidyl prolinol tert-butyldiphenylsilyl ether
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The development of a highly efficient, insoluble, and non-swelling MPS-supported organocatalyst for the direct asymmetric Michael reaction of ketones and aldehydes to nitrostyrenes at room temperature in water is described. Excellent yields (up to 100%) a
- Chuan, Yongming,Chen, Guihua,Peng, Yungui
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supporting information; body text
p. 3054 - 3058
(2009/10/11)
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- 4-Trifluoromethanesulfonamidyl prolinol tert-butyldiphenylsilyl ether as a highly efficient bifunctional organocatalyst for Michael addition of ketones and aldehydes to nitroolefins
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4-Trifluoromethanesulfonamidyl prolinol tert-butyldiphenylsilyl ether bifunctional organocatalyst 3a is a highly efficient catalyst for the asymmetric Michael addition reactions of ketones and aldehydes to nitrostyrenes, leading to syn-selective adducts with excellent yields (>99%), high diastereoselectivities (up to 99:1 dr) and excellent enantioselectivities (up to 99% ee). Control experiments suggested that the trans-configuration relationship between the bulky group (-CH2OTBDPS) and the sulfonamido group at the 4-position of the pyrrolidine ring was important to achieve high yield and stereoselectivity.
- Wang, Chao,Yu, Chun,Liu, Changlu,Peng, Yungui
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supporting information; experimental part
p. 2363 - 2366
(2009/08/17)
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- Practical syntheses of 4-fluoroprolines
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4-Fluoroprolines are among the most useful nonnatural amino acids in chemical biology. Here, practical routes are reported for the synthesis of the 2S,4R, 2S,4S, and 2R,4S diastereomers of 4-fluoroproline. Each route starts with (2S,4R)-4-hydroxyproline, which is a prevalent component of collagen and hence readily available, and uses a fluoride salt to install the fluoro group. Hence, the routes provide process-scale access to these useful nonnatural amino acids.
- Chorghade, Mukund S.,Mohapatra, Debendra K.,Sahoo, Gokarneswar,Gurjar, Mukund K.,Mandlecha, Manish V.,Bhoite, Nitin,Moghe, Santosh,Raines, Ronald T.
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scheme or table
p. 781 - 784
(2009/04/04)
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- Synthesis and DNA-binding ability of C2R-fluoro substituted DC-81 and its dimers
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C2R-Fluoro substituted DC-81 and its dimers have been synthesized that exhibit significant DNA-binding ability, particularly the five carbon alkane spacer compound (6c) showed the helix melting temperature (ΔTm) of 18.8 °C after incubation of 36 h at 37 °C.
- Kamal, Ahmed,Rajasekhar Reddy,Murali Mohan Reddy
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p. 803 - 806
(2007/10/03)
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- BICYCLIC PYRAZOLE DERIVATIVE
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A compound represented by the following formula (I), a prodrug thereof, or a pharmaceutically acceptable salt of either. These are compounds having high DPP-IV inhibitory activity and improved in safety, nontoxicity, etc. (I) [In the formula, R1 represents hydrogen, optionally substituted alkyl, etc.; the solid line and dotted line between A1 and A2 indicate a double bond (A1=A2), etc.; A1 represents a group represented by the formula C(R2), etc.; A2 represents a group represented by the formula C(R4), etc.; R2 represents hydrogen, optionally substituted alkyl, etc.; R4 represents hydrogen, optionally substituted alkyl, etc.; R6 represents hydrogen, optionally substituted aryl, etc.; and -Y represents, e.g.; a group represented by the formula (A): (A) (wherein ml is 0, 1, 2, or 3; and R7 is absent, or one or two R7's are present and each independently represents optionally substituted alkyl, etc.).]
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Page/Page column 179
(2010/11/30)
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- Chemotactic peptides: fMLF-OMe analogues incorporating proline-methionine chimeras as N-terminal residue
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The new fMLF analogues 1-4, incorporating chimeric S-proline-methionine residues (namely the homochiral cis-4(S)-methylthio-(S)-proline (10) and the heterochiral trans-4(R)-methylthio-(S)-proline) (17) in place of the native S-methionine, have been prepared; their solution conformation and activity as agonists or antagonists of formylpeptide receptors have been studied. In addition to peptides 1-4, which maintain the Met γ-thiomethyl-ether function, the analogues Boc-PLF-OMe (18) and For-PLF-OMe (19) devoid, as compared with 1-4, of position 1 side chain, have been synthesized and their activity examined.
- Mollica, Adriano,Paradisi, Mario Paglialunga,Varani, Katia,Spisani, Susanna,Lucente, Gino
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p. 2253 - 2265
(2007/10/03)
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- Compounds and compositions for use in the prevention and treatment of obesity and related syndromes
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The invention relates to 4-hydroxyisoleucine, isomers, analogs, lactones, salts, and prodrugs thereof, to processes for their preparation, and to pharmaceutical compositions comprising the same. More particularly, the invention relates to the use of those compounds in the prevention and treatment of obesity and related syndromes.
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Page/Page column 60
(2010/11/24)
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- Analogs of 4-hydroxyisoleucine and uses thereof
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The invention relates to analogs of 4-hydroxyisoleucine, and to lactones, pharmaceutically acceptable salts, and prodrugs thereof, to processes for their preparation, and to pharmaceutical compositions comprising the same. The analogs of the invention stimulate both glucose uptake and insulin secretion, and may thus be useful for the prevention and treatment of disorders of carbohydrate or lipid metabolism, including diabetes mellitus (type 1 and type 2 diabetes), pre-diabetes, and Metabolic Syndrome.
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Page/Page column 47
(2008/06/13)
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- VLA-4 ANTAGONISTS
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Compounds of Formula I are antagonists of VLA-4, and as such are useful in the inhibition or prevention of cell adhesion and cell-adhesion mediated pathologies. These compounds may be formulated into pharmaceutical compositions and are suitable for use in the treatment of inflammatory bowel disease including ulcerative colitis and Crohn’s disease, multiple sclerosis, asthma, and rheumatoid arthritis.
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Page/Page column 20
(2008/06/13)
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- The synthesis and biological activity of C2-fluorinated pyrrolo[2,1-c][1,4]benzodiazepines
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The novel C2-fluorinated pyrrolobenzodiazepines (1, 2 and 3) have been prepared from commercially available trans-hydroxyproline in good overall yield and were screened for in vitro cytotoxicity against a number of cancer cell lines. The 2R-fluoro isomer 2 exhibits an activity of 76 nM against the CH1 cell line.
- O'Neil, Ian A.,Thompson, Stephen,Kalindjian, S. Barret,Jenkins, Terence C.
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p. 7809 - 7812
(2007/10/03)
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- CYANOPYRROLIDINE DERIVATIVES
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A cyanopyrrolidine derivative represented by Formula (1): [wherein R1 is a halogen atom, a hydroxyl group, an alkoxy group having 1 to 5 carbon atoms or an alkyl group having 1 to 5 carbon atoms, R2 is a hydrogen atom, a halogen atom, a hydroxyl group, an alkoxy group having 1 to 5 carbon atoms or an alkyl group having 1 to 5 carbon atoms, or R1 and R2 together form an oxo, a hydroxyimino group, an alkoxyimino group having 1 to 5 carbon atoms or an alkylidene group having 1 to 5 carbon atoms, ???R3 and R4 are each a hydrogen atom, a halogen atom, a hydroxyl group, an alkoxy group having 1 to 5 carbon atoms or an alkyl group having 1 to 5 carbon atoms, or R3 and R4 together form an oxo, a hydroxyimino group, an alkoxyimino group having 1 to 5 carbon atoms or an alkylidene group having 1 to 5 carbon atoms, ???X is an oxygen atom or a sulfur atom, ???Y is -CR5R6- (wherein R5 and R6 are the same or different, and are each a hydrogen atom, a halogen atom, an optionally substituted alkyl group having 1 to 10 carbon atoms or an optionally substituted alkenyl group having 2 to 10 carbon atoms), or -CR7R8-CR9R10- (wherein R7, R8, R9 and R10 are the same or different, and each a hydrogen atom, a halogen atom or an optionally substituted alkyl group having 1 to 10 carbon atoms, or R7 and R9 together with the carbon atom to which they are attached form an optionally substituted cycloalkyl group having 3 to 8 carbon atoms, an optionally substituted cycloalkenyl group having 4 to 8 carbon atoms, an optionally substituted bicycloalkyl group having 5 to 10 carbon atoms, or an optionally substituted bicycloalkenyl group having 5 to 10 carbon atoms) and ???Z is a hydrogen atom or an optionally substituted alkyl group having 1 to 10 carbon atoms, or Y and Z together with the nitrogen atom to which they are attached form an optionally substituted cyclic amino group having 2 to 10 carbon atoms], or a pharmaceutically acceptable salt thereof.
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- Stereoelectronic effects on collagen stability: The dichotomy of 4-fluoroproline diastereomers
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Collagen is the most abundant protein in animals. Natural collagen consists of a triple helix of (Xaa-Yaa-Gly)n chains, in which the Xaa and Yaa residues are often l-proline. Here, a (2S,4S)-4-fluoroproline (flp) residue is shown to be greatly stabilizing in the Xaa position (but destabilizing in the Yaa position). In contrast, a (2S,4R)-4-fluoroproline (Flp) residue is shown to be greatly destabilizing in the Xaa position (but stabilizing in the Yaa position). The dichotomous effect of the diastereomers appears to arise from a gauche effect, which alters pyrrolidine ring pucker and hence properly (or improperly) preorganizes main-chain dihedral angles. Thus, the rational use of stereoelectronic effects can enhance the conformational stability of a protein. Copyright
- Hodgest, Jonathan A.,Raines, Ronald T.
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p. 9262 - 9263
(2007/10/03)
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- Synthesis and biological activity of 1-phenylsulfonyl-4-phenylsulfonylaminopyrrolidine derivatives as thromboxane A2 receptor antagonists
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The synthesis and biological activity of novel 1-phenylsulfonyl-4- phenylsulfonylaminopyrrolidine analogues are described. All compounds were produced through modification of the substituent formally corresponding to the 1,3-dioxane ring system and the ω-octenol side chain of thromboxane A2 (TXA2), in reference to the structure of Daltroban. Several compounds were found to be potent TXA2 receptor antagonists. Compound 51a was the most effective inhibitor of 9,11-epoxymethano PGH2 (U-46619)-induced rat aortic strip contraction (IC50 = 0.48 nM).
- Marusawa, Hiroshi,Setoi, Hiroyuki,Sawada, Akihiko,Kuroda, Akio,Seki, Jiro,Motoyama, Yukio,Tanaka, Hirokazu
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p. 1399 - 1415
(2007/10/03)
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- A convenient and high yield method to prepare 4-hydroxypyroglutamic acids
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RuO2/NaIO4 oxidation of N-Boc-4-silyloxy and 4-acetoxy proline methyl esters under ethyl acetate/water biphase condition gave N-Boc-4-silyloxy and 4-acetoxy pyroglutamic acid derivatives in high yields. Desilylation with TBAF afforded both cis- and trans-N-Boc-methyl-4-hydroxy pyroglutamates.
- Zhang, Xiaojun,Schmitt, Aaron C.,Jiang, Wen
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p. 5335 - 5338
(2007/10/03)
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- Pyrrolidine inhibitors of human cytosolic phospholipase A2. Part 2: Synthesis of potent and crystallized 4-triphenylmethylthio derivative 'pyrrophenone'
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We synthesized a potent and crystallized human cytosolic phospholipase A2α inhibitor, pyrrophenone (6) which inhibits the isolated enzyme with an IC50 value of 4.2 nM. Pyrrophenone shows potent inhibition of arachidonic acid release, prostaglandin E2, thromboxane B2, and leukotriene B4 formation in human whole blood. The magnitudes of prostaglandin E2 and thromboxane B2 inhibition are the same as those of indomethacin.
- Eno, Kaoru,Okuno, Takayuki,Nishi, Koichi,Murakami, Yasushi,Yamada, Katsutoshi,Nakamoto, Shozo,Ono, Takashi
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p. 587 - 590
(2007/10/03)
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- Practical synthesis of Boc and Fmoc protected 4-fluoro and 4-difluoroprolines from trans-4-hydroxyproline
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Boc-cis-4-fluoro-L-proline and 4-difluoro-L-proline, usable in classical peptide synthesis, were obtained in respectively 71% (3 steps) and 65% (4 steps) overall yields from the readily available trans-4-hydroxy-L-proline methyl ester. The corresponding fluorinated trans-isomer was isolated in 24% yield (5 steps). Transformation of Boc-protected compounds to their Fmoc-equivalents was performed in high yields.
- Demange, Luc,Menez, Andre,Dugave, Christophe
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p. 1169 - 1172
(2007/10/03)
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- Synthesis of new building blocks for peptide nucleic acids containing monomers with variations in the backbone
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New PNA monomers containing aminoprolines or pyrrolidines as backbones have been synthesized. Oligomerisation was carried out on a solid support. Resistance to enzymatic degradation was tested.
- Jordan, Stephan,Schwemler, Christoph,Kosch, Winfried,Kretschmer, Axel,Schwenner, Eckhardt,Stropp, Udo,Mielke, Burkhard
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p. 681 - 686
(2007/10/03)
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- Synthesis and modification of a novel 1 β-methyl carbapenem antibiotic, S-4661
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We describe an efficient method for introducing a sulfamoylamino group into the C-2' position of pyrrolidine using the Mitsunobu reaction. S-4661, its N-methyl analogues and stereoisomers were synthesized using this method and their structure-activity relationships were investigated.
- Iso,Irie,Iwaki,Kii,Sendo,Motokawa,Nishitani
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p. 478 - 484
(2007/10/03)
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- Pyrrolidylthiocarbapenem derivative
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A pyrrolidylthiocarbapenem derivative represented by Formula I is provided: STR1 wherein R1 is hydrogen or lower alkyl; R2, R3 and R4 are hydrogen, lower alkyl which can be substituted or an amino protecting group independently, or R2 and R3 together with a nitrogen atom to which R2 and R3 are bonded form a saturated or unsaturated cyclic group, or R2 and R4, or R3 and R4 together with two nitrogen atoms and one sulfur atom in the sufamide group form a saturated or unsaturated cyclic group; each cyclic group can further include at least one atom selected from the group consisting of oxygen, sulfur and nitrogen, and each cyclic group can be substituted; X1 is hydrogen or a hydroxy protecting group; X2 is hydrogen, a carboxy protecting group, an ammonio group, an alkali metal or an alkaline-earth metal; and Y2 is hydrogen or an amino protecting group.
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