- Condensation approach to aliphatic oligourea foldamers: Helices with N-(Pyrrolidin-2-ylmethyl)ureido junctions
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Caught in a fold: A simple and efficient coupling strategy to make aliphatic oligourea foldamers is reported. Crystal structures show that the pyrrolidine units (red; see picture) do not impair the 2.5-helical folding of the oligoureas. This modular strategy enables assembly of long helical segments containing non-adjacent pyrrolidine units as exemplified by the synthesis of a helix that is approximately 40 long.
- Fremaux, Juliette,Fischer, Lucile,Arbogast, Thomas,Kauffmann, Brice,Guichard, Gilles
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- N-arenesulfonyl-2-aminomethylpyrrolidmes - Novel modular ligands and organocatalysts for asymmetric catalysis
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A novel series of (S)-N-arenesulfonyl-2-aminomethylpyrrolidines were prepared in high overall yield starting from N-Boc-L-proline. The mono-sulfonyldiamines were evaluated as organocatalysts in the asymmetric α-amination of propanal using diethyl azadicarboxylate (DEAD) as the amine source. The initially formed α-aminated aldehyde was reduced in situ to the corresponding N-aminooxazolidinone, which was obtained in moderate to high yield in up to 87% ee.
- Dahlin, Nils,Bogevig, Anders,Adolfsson, Hans
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- Synthesis and in vivo evaluation of 11C-labeled (1,7-dicarba-closo-dodecaboran-1-yl)-N-{[(2S)-1-ethylpyrrolidin-2-yl]methyl} amide
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Boron clusters, and especially dicarba-closo-dodecaboranes, can be used as hydrophobic pharmacophores in the design of new drugs and radiotracers because of their hydrophobic character, spherical structure, and excellent chemical and photochemical stability. In the present paper, the synthesis and in vivo evaluation of 11C-labeled (1,7-dicarba-closo-dodecaboran-1-yl)-N- {[(2S)-1-ethylpyrrolidin-2-yl]methyl}amide, an analog of the D2 receptor ligand [11C]raclopride, is described. The radiosynthesis was approached by reaction of the demethylated precursor with [11C] CH3I in basic media; moderate radiochemical yields (18.2 ± 2.8%, decay corrected), and excellent radiochemical purities (>98%) were obtained in overall synthesis time of ~50 min. In vivo assays showed a biodistribution pattern with significant uptake in liver, kidneys and lungs at short times (t = 4 min) after administration and increasing accumulation in bladder at longer times (t ≥ 14.5 min). Although brain positron emission tomography scans showed good blood brain barrier penetration, the high unspecific uptake observed in different brain regions impedes its applicability as D2 receptor ligand.
- G?mez-Vallejo, Vanessa,Vázquez, Naiara,Gona, Kiran Babu,Puigivila, Maria,González, Mikel,Sebastián, Eneko San,Martin, Abraham,Llop, Jordi
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- Synthesis of D2 receptor ligand analogs incorporating one dicarba-closo-dodecaborane unit
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Boron clusters, and especially dicarba-closo-dodecaboranes, can be used as hydrophobic pharmacophores in the design of new drugs and radiotracers. In the current Letter, analogs of enantiomeric substituted benzamides (Raclopride and FLB-457) in which the phenyl ring has been substituted by a carborane cage (either orto- or meta-carborane) have been developed as potential D2 receptor antagonists. The formation of intramolecular hydrogen bonds (in solution) and the stability of the new chemical entities have been evaluated by means of 1H NMR and HPLC-MS, respectively.
- Vázquez, Naiara,Gómez-Vallejo, Vanessa,Calvo, Javier,Padro, Daniel,Llop, Jordi
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- Application of Proline-Derived (Thio)squaramide Organocatalysts in Asymmetric Diels-Alder and Conjugate Addition Reactions
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The synthesis of chiral proline-derived squaramide and thiosquaramide organocatalysts, which are capable of the dual activation in asymmetric reactions is reported. The (thio)squaramide moiety can form hydrogen bonds to activate the substrates and to stereocontrol the reaction, while the pyrrolidine unit can form enamines to activate carbonyl compounds via aminocatalysis. Comparing the performance of thiosquaramide to squaramide, the Diels Alder reaction of (anthracen-9-yl)acetaldehyde and trans-?-nitrostyrene was examined, which has been investigated in the literature using quantum chemical calculations. Both squaramide and thiosquaramide gave excellent yields (up to 99%) and enantiomeric excess values (up to 98%). Moreover, their catalytic performance was compared in conjugate addition of lawsone to ?,?-unsaturated ?-keto ester.
- Bagi, Péter,Dargó, Gyula,Drahos, László,Huszthy, Péter,Kis, Dávid,Kupai, József,Mátrav?lgyi, Béla,Nagy, Sándor,Tóth, Blanka
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- N-Sulfinylpyrrolidine-containing ureas and thioureas as bifunctional organocatalysts
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The synthesis of bifunctional N-sulfinylureas and thioureas with an appended pyrrolidine unit is presented. These organocatalysts were evaluated in Michael additions of aldehydes to nitroalkenes both under solvent-free conditions and in solution. The N-su
- ?ebesta, Radovan,Górová, Renata,Kri?tofíková, Dominika,Meciarová, Mária,Némethová, Boglárka,Polácková, Viera
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p. 2629 - 2641
(2021/11/30)
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- D -Prolyl-2-(trifluoromethylsulfonamidopropyl)pyrrolidine: An Organocatalyst for Asymmetric Michael Addition of Aldehydes to β-Nitroalkenes at Ambient Conditions
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Four 2-(trifluoromethylsulfonamidoalkyl)pyrrolidines and their d-prolinamides were prepared and screened as organocatalysts for the Michael addition reaction of aldehydes with β-nitroalkenes at rt and without the use of additives. d-Prolyl-2-(trifluoromet
- Gorde, Amol B.,Ramapanicker, Ramesh
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p. 1523 - 1533
(2019/02/07)
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- BENZIMIDAZOLE-LINKED INDOLE COMPOUND ACTING AS NOVEL DIVALENT IAP ANTAGONIST
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The present invention discloses a benzimidazole-linked indole compound acting as novel divalent IAP antagonist, specifically disclosing the compound shown in fomulas (I) or a pharmaceutically acceptable salt thereof.
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Paragraph 0112; 0114
(2019/03/14)
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- Synthesis of new enantiopure thioureas derived from (S)-proline
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Enantiopure thiourea derivatives, containing pyrrolidine ring, were prepared by the reaction of N-Boc-(S)-2-aminomethylpyrrolidine (6) with thioisocyanates 8.
- Wroblewska, Aneta,Mloston, Grzegorz
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p. 509 - 511
(2013/07/25)
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- Stereoselective synthesis of chiral pyrrolidine derivatives of (+)-α-pinene containing a β-amino acid moiety
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We report the synthesis of several enantiopure pyrrolidine derivatives containing a β-amino acid moiety. These novel chiral compounds were prepared through stereospecific chlorosulfonyl isocyanate (CSI) addition to the readily available, natural terpene (+)-α-pinene. Coupling of N-Boc-protected β-amino acid derivatives with various bulky amines and amino acids using the mixed anhydride activation method, followed by N-deprotection, afforded the corresponding chiral amino amides in good yields. Despite the severe steric hindrance anticipated in α-pinene-based heterocycles, efficient coupling of the amino amides and an amino ester with the acyl chloride of N-Cbz-protected (S)-proline provided the corresponding pyrrolidinic pinene derivatives in good yields. Moreover, a convenient synthesis of N-Cbz- and N-Boc-monoprotected (S)-prolinamine is reported. Georg Thieme Verlag Stuttgart New York.
- Vega-Penaloza, Alberto,Sanchez-Antonio, Omar,Escudero-Casao, Margarita,Tasnadi, Gabor,Fueloep, Ferenc,Juaristi, Eusebio
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p. 2458 - 2468
(2013/09/23)
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- Design, synthesis and catalytic property of L-proline derivatives as organocatalysts for direct aldol reaction
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A series of chiral prolinamide compounds with pyridine-2, 6-dicarboxylic acid moieties derived from L-proline have been designed and synthesized, their catalytic properties for direct asymmetric aldol reactions were also studied in this article. These catalysts gave the aldol product in high yield (87%) and high enantioselectivity, up to 85%, of the anti-structure at room temperature but gave disappointing results at a lower temperature or when additive was added. Conditions, including solvents, temperature and additives were screened for the reactions. Moreover, the influence of presence of water on yield and stereoselectivity was also discussed. Copyright
- Wang, Lei,Tang, Ruiren,Yang, Hua
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p. 591 - 598
(2013/11/06)
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- Synthesis of chiral NADH analog based on proline template including thiourea and nicotinic acid moieties
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Chiral reductase-mimicking organic molecule built on proline template incorporating a covalently bound NADH mimic via thiourea, and related reducing agent Hantzsch dihydropyridine, was designed. A synthetic path was developed involving interlinking of chiral proline derivatives with thiourea and subsequent coupling reaction with nicotinoyl chloride. The structure of target compound was studied by x-ray, indicating a double H bond with thiourea hydrogens and oxygen O1 of benzylcarbamate fragment. The reduction of benzil and imines was performed. Taylor & Francis Group, LLC.
- Bagdziunas, Gintautas,Haukka, Matti,Butkus, Eugenijus
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scheme or table
p. 2517 - 2523
(2011/08/07)
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- Functionalized proline with double hydrogen bonding potential: Highly enantioselective Michael addition of carbonyl compounds to β-nitrostyrenes in brine
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Simple synthetic manipulation of S-proline allows access to prolinamides 5-7 as organocatalysts capable of double hydrogen bonding for enantioselective Michael addition reactions of carbonyl compounds to β-nitrostyrenes. It is shown that prolinamide catalyst 7 leads to addition products with a high diastereo- as well as enantioselectivity. The transition state structure involving the binding of electrophilic nitrostyrene via two H-bonds is believed to be further stabilized by π,π stacking interactions mediated by the tosyl ring.
- Saha, Satyajit,Seth, Saona,Moorthy, Jarugu Narasimha
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supporting information; experimental part
p. 5281 - 5286
(2010/11/03)
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- Asymmetric organocatalysis of the addition of acetone to 2-nitrostyrene using N-diphenylphosphinyl-1,2-diphenylethane-1,2-diamine (PODPEN)
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The highly enantioselective addition of acetone to 2-nitrostyrene, using N-diphenylphosphinyl-trans-1,2-diphenylethane-1,2-diamine (PODPEN) as a catalyst, is described.
- Morris, David J.,Partridge, A. Simon,Manville, Charles V.,Racys, Daugidas T.,Woodward, Gary,Docherty, Gordon,Wills, Martin
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supporting information; experimental part
p. 209 - 212
(2010/03/24)
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- Recyclable merrifield resin-supported organocatalysts containing pyrrolidine unit through A3-coupling reaction linkage for asymmetric michael addition
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Merrifield resin-supported pyrrolidine-based chiral organocatalysts A2D through A3-coupling reaction linkage have been developed and found to be highly effective catalysts for the Michael addition reaction of ketones with nitrostyrenes. The rea
- Liu, Jie,Li, Pinhua,Zhang, Yicheng,Ren, Kai,Wang, Lei,Wang, Guanwu
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experimental part
p. 432 - 441
(2012/04/23)
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- Isoselenocyanates derived from Boc/Z-amino acids: Synthesis, isolation, characterization, and application to the efficient synthesis of unsymmetrical selenoureas and selenoureidopeptidomimetics
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Isoselenocyanates derived from Boc/Z-amino acids are prepared by the reaction of the corresponding isonitriles with selenium powder in presence of triethylamine at reflux. The utility of these new classes of isoselenocyanates in the preparation of selenoureidodipeptidomimetics possessing both amino as well as carboxy termini has been accomplished. The 1H NMR analysis confirmed that the protocol involving the conversion of isonitriles to isoselenocyanates and their use as coupling agents in assembling selenoureido derivatives is free from racemization.
- Chennakrishnareddy, Gundala,Nagendra, Govindappa,Hemantha, Hosahalli P.,Das, Ushati,Guru Row, Tayur N.,Sureshbabu, Vommina V.
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supporting information; experimental part
p. 6718 - 6724
(2010/09/30)
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- Pyrrolidine-ureas as bifunctional organocatalysts for asymmetric Michael addition of ketone to nitroalkenes: Unexpected hydrogen bonding effect
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A series of pyrrolidine-urea bifunctional organocatalysts was efficiently synthesized and applied to the asymmetric Michael addition of ketone to nitroolefin. Theoretical study was performed to shed light on the origin of their different activities and revealed that the rigid structure formed between catalyst 1b with nitroolefin via double hydrogen bonding retarded the approach of nucleophilic enamine intermediate.
- Cao, Xiao-Yu,Zheng, Jun-Cheng,Li, Yu-Xue,Shu, Zhen-Cao,Sun, Xiu-Li,Wang, Bi-Qin,Tang, Yong
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supporting information; experimental part
p. 9703 - 9707
(2011/03/17)
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- PYRIMIDODIAZEPINONE DERIVATIVE
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The invention provides a pyrimidodiazepinone derivative represented by the general formula (I) [wherein n represents 1 or 2, Z represents a hydrogen atom or the like, R1 and R2 may be the same or different, and each represents a hydrogen atom or the like, A represents a bond, (CH2)m (wherein m represents an integer of 1 to 4), optionally substituted phenylene, optionally substituted pyridinediyl, or C=O, R3 represents a hydrogen atom, optionally substituted lower alkyl, or the like, and R4 represents a hydrogen atom or the like], or a pharmaceutically acceptable salt thereof or the like.
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Page/Page column 49
(2010/04/24)
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- Synthesis and thermal reactivity of pyrrolidine- and 2-pyrrolidinone-fused cyclic enediynes
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Various bicyclic enediynes containing pyrrolidine and pyrrolidinone moieties were synthesised. Thermal reactivity studies indicated the lowering of the onset temperature for Bergman cyclisation upon fusion of these heterocyclic systems onto the cyclic ene
- Roy, Basab,Basak, Amit
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p. 2804 - 2806
(2008/02/11)
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- 4-Substituted prolyl sulfonamides as enantioselective organocatalysts for aldol reactions
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A series of prolyl and 4-substituted prolyl sulfonamides were prepared and were evaluated as organocatalysts of asymmetric aldol reaction. Using prolyl methanesulfonamide, 4-benzyloxy-prolyl methanesulfonamide and toluenesulfonamide and 4-hydroxy-prolyl t
- Bellis, Evagelos,Vasilatou, Konstantina,Kokotos, George
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p. 2407 - 2413
(2007/10/03)
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- NOVEL INHIBITORS OF FARNESYL-PROTEIN TRANSFERASE
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Novel compounds and pharmaceutical compositions are disclosed which are inhibitors of the enzyme, farnesyl-protein transferase. Also disclosed is a method of inhibiting Ras function and therefore inhibiting the abnormal growth of cells. The method comprises administering the novel aminooxyamide compound to a biological system. In particular, the method inhibits the abnormal growth of cells in a mammal such as a human.
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Page/Page column 89
(2010/02/12)
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- INHIBITORS OF HUMAN TUMOR-EXPRESSED CCXCKR2
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Pharmaceutical compositions containing organic compounds or salts thereof that serve as modulators for the SDF-1 or I-TAC chemokines are disclosed. The compounds and compositions are useful in the treatment of cancer, especially in the inhibition of cancer proliferation, growth, and metastasis. Methods of interfering with SDF-1 and/or I-TAC binding to the CCXCKR2 receptor and treating cancer using the compounds and pharmaceutical compositions of the present invention are also disclosed.
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- Synthesis and hybridization of novel chiral pyrrolidine based PNA analogue
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Four different PNA fragments containing units of either the R- or S- isomer of N-(2-pyrrolidine-methyl)-N-(thymine-1-acetyl)-glycine (Pmg) were synthesized on a solid support. UV thermal melting experiments with complementary RNAs were performed and it was found that R-Pmg containing PNAs bind better to RNA than those containing the S-Pmg units.
- Slaitas,Yeheskiely
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p. 1377 - 1379
(2007/10/03)
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