85613-64-5Relevant academic research and scientific papers
A process for the preparation method of the sulfuric acid [...] intermediates
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Paragraph 0025; 0026, (2019/07/08)
The invention discloses a method for preparing sulfuric acid [...] intermediate (2 R, 3 S) - 1, 2 - epoxy - 3 - tert-butoxycarbonyl amino - 4 - phenyl butane of the method, the method cheap L - phenylalanine as the starting material, by with the di-T-n-butyl reaction for protecting amino group, with acetic anhydride condensation, with hydrochloric acid after the occurrence of the chloro in the chiral catalyst under the effects of the asymmetric hydrogenation reduction, finally cyclization under basic conditions to obtain the target product. The present invention provides of sulfuric acid is an important intermediate [...] (2 R, 3 S) - 1, 2 - epoxy - 3 - tert-butoxycarbonyl amino - 4 - phenyl butane preparation method of the raw material is cheap, mild reaction conditions, the synthesis efficiency is high, it is suitable for industrial production, in order to prepare sulfuric acid [...] and intermediate provides a highly efficient way.
The Enantioselective Dakin-West Reaction
Wende, Raffael C.,Seitz, Alexander,Niedek, Dominik,Schuler, S?ren M. M.,Hofmann, Christine,Becker, Jonathan,Schreiner, Peter R.
, p. 2719 - 2723 (2016/02/27)
Here we report the development of the first enantioselective Dakin-West reaction, yielding α-acetamido methylketones with up to 58 % ee with good yields. Two of the obtained products were recrystallized once to achieve up to 84 % ee. The employed methylimidazole-containing oligopeptides catalyze both the acetylation of the azlactone intermediate and the terminal enantioselective decarboxylative protonation. We propose a dispersion-controlled reaction path that determines the asymmetric reprotonation of the intermediate enolate after the decarboxylation.
A palladium iodide-catalyzed carbonylative approach to functionalized pyrrole derivatives
Gabriele, Bartolo,Veltri, Lucia,Mancuso, Raffaella,Salerno, Giuseppe,Maggi, Sabino,Aresta, Brunella Maria
experimental part, p. 4005 - 4016 (2012/06/18)
A novel and convenient approach to functionalized pyrroles is presented, based on Pd-catalyzed oxidative heterocyclization-alkoxycarbonylation of readily available N-Boc-1-amino-3-yn-2-ols. Reactions were carried out in alcoholic solvents at 80-100 °C and under 20 atm (at 25 °C) of a 4:1 mixture of CO-air, in the presence of the PdI2-KI catalytic system (2-5 mol % of PdI2, KI/PdI2 molar ratio = 10). In the case of N-Boc-1-amino-3-yn-2-ols 3, bearing alkyl or aryl substituents, the carbonylation reaction led to a mixture of Boc-protected and N-unsubstituted pyrrole-3-carboxylic esters 4 and 5, respectively. This mixture could be conveniently and quantitatively converted into deprotected pyrrole-3-carboxylic esters 5 by a simple basic treatment. In the case of diastereomeric (3RS,4RS)- and (3RS,4SR)-N-Boc-3-amino-2-methyldec-5-yn-4-ol (syn-3f and anti-3f, respectively, whose relative configuration was determined by X-ray crystallographic analysis), no particular difference was observed in the reactivity of the two diastereomers between them and with respect to the diastereomeric mixture (3S,4S) + (3S,4R). Interestingly, N-Boc-2-alkynyl-1- amino-3-yn-2-ols 6, bearing an additional alkynyl substituent α to the hydroxyl group, spontaneously underwent N-deprotection under the reaction conditions and regioselective water addition to the alkynyl group at C-3 of the corresponding pyrrole-3-carboxylic ester derivative, thus directly affording highly functionalized pyrrole derivatives 7 in one step. In a similar manner, a novel functionalized dihydropyrrolizine derivative 9 was directly synthesized starting from (S)-7-(pyrrolidin-2-yl)trideca-5,8-diyn-7-ol 8.
Access to enantiomerically enriched cis-2,3-disubstituted azetidines via diastereoselective hydrozirconation
Pradhan, Tarun K.,Krishnan, K. Syam,Vasse, Jean-Luc,Szymoniak, Jan
supporting information; experimental part, p. 1793 - 1795 (2011/06/19)
An asymmetric variant of the hydrozirconation reaction has been established starting from Boc-protected chiral allylic amines. The resulting diastereoselectively formed N-functionalized organozirconiums can be considered as promising chirons. In this case
Design, synthesis, and biological evaluation of novel fluorinated ethanolamines
Fustero, Santos,Cunat, Ana C.,Flores, Sonia,Baez, Claribel,Oliver, Judit,Cynamon, Michael,Guetschow, Michael,Mertens, Matthias D.,Delgado, Oscar,Tresadern, Gary,Trabanco, Andres A.
, p. 14772 - 14784 (2012/02/03)
The preparation of novel fluorinated allylamines and their use as key fragments for the stereoselective synthesis of hydroxyethyl secondary amine (HEA)-type peptidomimetics is described. Our strategy employs chiral sulfinyl imines as synthesis intermediates, by treatment of hemiaminal precursors with two equivalents of vinylmagnesium bromide. The subsequent oxidation of the allylic amines to the corresponding epoxides was achieved by treatment with methyl(trifluoromethyl)dioxirane. Finally, epoxide ring opening with a range of nitrogen nucleophiles provided a library of HEA-derived peptidomimetics with a phenyldifluoromethylene moiety. The biological evaluation of these derivatives revealed compounds with remarkable BACE1 inhibitory activity. Docking studies revealed the influence of the fluorine atoms in the binding mode of the synthesized ligands. Furthermore, the biological evaluation of our final products and synthesis intermediates led to the discovery of compounds with antimicrobial activity against Mycobacterium and Nocardia species.
Trisubstituted (E)-alkene dipeptide isosteres as β-turn promoters in the gramicidin S cyclodecapeptide scaffold
Xiao, Jingbo,Weisblum, Bernard,Wipf, Peter
, p. 4731 - 4734 (2007/10/03)
(Chemical Equation Presented) A concise synthesis of a gramicidin S analogue with trisubstituted (E)-alkene dipeptide isostere (TEADI) replacements at both D-Phe-Pro positions was realized. Conformational analysis demonstrated that TEADIs can serve as typ
Dihalomethylation of N-protected phenylalanine esters
Onishi, Tomoyuki,Otake, Yasuyuki,Hirose, Naoko,Nakano, Takashi,Torii, Takayoshi,Nakazawa, Masakazu,Izawa, Kunisuke
, p. 6337 - 6340 (2007/10/03)
Dihalomethylation of several N-protected amino acid esters gave N-protected α-aminoalkyl-α′-dihalomethylketones, which are useful intermediates for the synthesis of erythro β-amino-α-hydroxycarboxylic acids, in good yield. The dihalomethylketones were successfully converted to N-protected α-aminoalkyl-α′-halomethylketones by selective catalytic hydrogenation.
Aryl ketones as novel replacements for the C-terminal amide bond of succinyl hydroxamate MMP inhibitors
Sheppard, George S.,Florjancic, Alan S.,Giesler, Jamie R.,Xu, Lianhong,Guo, Yan,Davidsen, Steven K.,Marcotte, Patrick A.,Elmore, Ildiko,Albert, Daniel H.,Magoc, Terrance J.,Bouska, Jennifer J.,Goodfellow, Carole L.,Morgan, Douglas W.,Summers, James B.
, p. 3251 - 3256 (2007/10/03)
A series of succinyl hydroxamate MMP inhibitors were prepared incorporating an aryl amino ketone moiety in place of the more typical C- terminal amino acid amides. Compounds of the C-terminal ketone series displayed potent inhibition of MMPs. Several comp
Inactivation of serine protease, α-chymotrypsin by fluorinated phenylalanine analogues
Ohba, Tsuyoshi,Ikeda, Eitatsu,Takei, Hisashi
, p. 1875 - 1880 (2007/10/03)
Fluorinated phenylalanine analogues were found to be slow-binding or reversible competitive inhibitors of α-chymotrypsin. A series of these compounds were designed to inactivate α-chymotrypsin as a result of the formation of hydrogen-bonding between fluorine atom of the inhibitors and the amide protons known as oxy-anion hole in the active-site of serine and cysteine proteases.
Allylboration of α-Amino Ketones
Pace, R. David,Kabalka, George W.
, p. 4838 - 4844 (2007/10/02)
A series of unsaturated α-amino alcohols were prepared via the allylboration of the corresponding N-protected α-amino ketones.The reactions are stereoselective, producing the syn isomers.The diastereoselectivity is not dramatically affected by the electro
