- Method for synthesizing chiral 4-(N-carbobenzoxy) pyrrolidone
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The invention provides a method for synthesizing chiral 4-(N-carbobenzoxy) pyrrolidone. L-asparaginate is adopted as an initial raw material, through four steps of reactions of amino protection, diazo-reactions, carbonyl reduction and cyclization, chiral 4-(N-carbobenzoxy) pyrrolidone is prepared, raw materials are low in price and easy to obtain, chiral resolution is not needed in the reaction process, the yield is high, the reaction speed is rapid, a small amount of byproducts are generated, and the method is very applicable to industrial application.
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Paragraph 0025-0029
(2019/10/01)
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- Total Synthesis of cis-Clavicipitic Acid from Asparagine via Ir-Catalyzed C-H bond Activation as a Key Step
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4-Substituted tryptophan derivatives and the total synthesis of cis-clavicipitic acid were achieved in reactions in which Ir-catalyzed C-H bond activation was a key step. The starting material for these reactions is asparagine, which is a cheap natural amino acid. The reductive amination step from the 4-substituted tryptophan derivative gave cis-clavicipitic acid with perfect diastereoselectivity.
- Tahara, Yu-Ki,Ito, Mamoru,Kanyiva, Kyalo Stephen,Shibata, Takanori
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p. 11340 - 11343
(2015/08/03)
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- An access to aza-Freidinger lactams and E-locked analogs
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Freidinger lactams, possessing a peptide bond configuration locked to Z, are important key elements of conformationally restricted peptidomimetics. In the present work, the CαHi+1 unit has been replaced by N, leading to novel aza-Fre
- Ottersbach, Philipp A.,Schmitz, Janina,Schnakenburg, Gregor,Gütschow, Michael
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supporting information
p. 448 - 451
(2013/04/11)
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- Synthesis of imidazolidin-2-one-4-carboxylate and of (tetrahydro)pyrimidin- 2-one-5-carboxylate via an efficient modification of the Hofmann rearrangement
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A mild and efficient methodology for the rearrangement of protected asparagine and protected glutamine is reported; good results are obtained with a wide selection of protecting groups. The Royal Society of Chemistry.
- Angelici, Gaetano,Contaldi, Simone,Lynn Green, Sarah,Tomasini, Claudia
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experimental part
p. 1849 - 1852
(2008/10/09)
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- Utility of tetrathiomolybdate and tetraselenotungstate: Efficient synthesis of cystine, selenocystine, and their higher homologues
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Efficient synthesis of cystine, selenocystine, and their higher homologues like homo and bishomo amino acid derivatives from natural amino acid derivatives using tetrathiomolybdate and tetraselenotungstate reagents under mild and neutral conditions is reported. The generality of the reaction has been studied by capping various groups to amino and carboxyl components of canonical amino acids.
- Bhat, Ramakrishna G.,Porhiel, Emmanuel,Saravanan, Vadivelu,Chandrasekaran, Srinivasan
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p. 5251 - 5253
(2007/10/03)
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- Co-ordination chemistry of 3S-aminopyrrolidine and 3S-(methyl-amino)pyrrolidine: Crystallisation of the two diastereomers of dichloro[3S-(R,S-methylamino)pyrrolidine]palladium(II)
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Complexes of divalent Cu, Ni, Pd and Pt with 3S-aminopyrrolidine (S-ap) have been prepared and characterised by a combination of NMR, CD, electronic, IR and microanalytical techniques. The chosen chirality of the stereogenic carbon (S) forces the secondary nitrogen to adopt the R stereochemistry on co-ordination with the conformation of the 5-membered chelate being λ. The planar [M(S-ap)2]2+ complexes exist as a mixture of cis and trans isomers in the solid state and in solution. The trans arrangement is forced upon co-ordination of an axial donor (X = halide, thiocyanate or nitrite) in the five-co-ordinate ions [Cu(S-ap)2X]+. Methylation of the primary amine of S-ap generates another secondary nitrogen centre in the new ligand 3S-(methylamino)pyrrolidine, S-meap. This exocyclic nitrogen is not restricted to a single configuration on co-ordination. The complexes [M(S-meap)Cl2], where M = Pd or Pt, have been prepared and characterised. Both diastereoisomers (R- and S-NMe) of [Pd(S-meap)Cl2] crystallise from aqueous solution as distinct crystal forms which can be separated by mechanical means. The structure of the NMe(R) isomer has been determined by X-ray crystallography.
- Newman, Paul D.,Hursthouse, Michael B.,Malik, K. M. Abdul
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p. 599 - 606
(2007/10/03)
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- Regioselective reductions of various 3-aminosuccinimides; application to the synthesis of two heterocyclic systems
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The synthesis of novel pyrrolo[3,2-c]isoquinolines is investigated starting from 3-aminosuccinimides. Various known routes leading to 3-aminosuccinimides were tested but a new approach via nucleophilic addition of arylalkylamines on maleimide gave better results. The regioselectivity of the reduction of these compounds was shown to depend on the degree of substitution of the concerned 3-aminosuccinimide. The hydroxylactams are formed in-situ, then converted into the ethoxylactams. The latter, after generation of an iminium salt, afforded the target pyrroloisoquinolines and two further derivatives of another new heterocyclic system: the 3,6-methano-2,5-benzodiazocine.
- Briere, Jean-Francois,Charpentier, Patricia,Dupas, Georges,Queguiner, Guy,Bourguignon, Jean
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p. 2075 - 2086
(2007/10/03)
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- Handy access to chiral N,N'-disubstituted 3-aminopyrrolidines
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A new and rapid synthesis of (S)-3-aminopyrrolidines Z is proposed from N-protected (S)-Asparagine. Basic cyclization of methyl N-Z-(S)-Asparaginate 1 followed by one-pot N-benzylation directly leads to (S)-aminosuccinimide 3 which, after cleavage of the
- Maddaluno,Corruble,Leroux,Ple,Duhamel
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p. 1239 - 1242
(2007/10/02)
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- Cyclo-(L-asparagyl-L-asparagyl) : Preparation and Crystal Structure
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Two methods are described for the preparation of optically pure cyclo-(L-asparagyl-L-asparagyl) : (i) by self-condensation of (S)-3-aminopyrrolidine-2,5-dione in refluxing acetonitrile, and (ii) by self-co
- Howes, Colin,Alcock, Nathaniel W.,Golding, Bernard T.,McCabe, Richard W.
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p. 2287 - 2291
(2007/10/02)
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