383-70-0Relevant articles and documents
N-TFA-Gly-Bt-based stereoselective synthesis of substituted 3-amino tetrahydro-2 h-pyran-2-ones via an organocatalyzed cascade process
Han, Liuqing,Li, Ke,Mei, Tao,Qu, Jingping,Song, Yuming,Sun, Yali,Xu, Haitong
, (2019)
Chiral-substituted 3-amino tetrahydro-2H-pyran-2-ones were prepared in excellent enantioselectivities (up to 99percent ee) via an organo-catalyzed cascade procedure with N-TFA-Gly-Bt and α,β-unsaturated aldehydes as the substrates. The corresponding tetra
Stereoselective synthesis of proline-derived dipeptide scaffolds (prom-3 and prom-7) rigidified in a PPII helix conformation
Reuter, Cedric,Kleczka, Margarethe,De Mazancourt, Sarah,Neudoerfl, Joerg-Martin,Kuehne, Ronald,Schmalz, Hans-Guenther
, p. 2664 - 2667 (2014)
Following a peptide coupling/metathesis-based strategy, the two diastereomeric scaffolds ProM-3 and ProM-7 were stereoselectively synthesized (as 9-fluorenylmethoxycarbonyl derivatives), and their configuration was unambiguously proven by means of X-ray crystallography. The required dehydroisoleucine building blocks were prepared by applying the enantioselective Kazmaier-Claisen rearrangement. The target compounds represent dipeptide analogs rigidified in a PPII helix conformation, which are of interest for the development of new proteomimetics that selectively bind to protein domains specialized in the recognition of ligands adopting a PPII helix secondary structure. Starting from amino acid building blocks with an olefin side chain, the diastereomeric scaffolds ProM-3 and ProM-7 are synthesized through peptide coupling and ring-closing metathesis. The conformationally defined dipeptide analogs are of interest as building blocks for the synthesis of modular PPII helix secondary structure mimetics as tailored inhibitors of protein-protein interactions. Copyright
BF3·OEt2-TFAA Mediated Tetra-Functionalization of Amino Acids-Synthesis of Di-and Tri-Substituted 2-Trifluoromethyl Oxazoles in One Pot
Karuppusamy, Velusamy,Ilangovan, Andivelu
, p. 7147 - 7151 (2020)
A highly efficient, TFAA-BF3·OEt2 mediated multicomponent coupling of amino acid, TFAA, and aromatics provides a broad library of 2-Trifluoromethyl equipped 2,5-disubstituted/2,4,5-Trisubstituted oxazoles or N-(trifluoroacetyl)-β-Aminoalkyl ketones. This amino acid tetra-functionalization approach involves amidation (C-N), anhydride (C-O), Friedel-Crafts acylation (C-C), and Robinson-Gabriel annulation (C-O) followed by dehydrative aromatization. This reaction takes place under operationally simple, mild, and metal-free conditions using readily available amino acids and aromatic compounds.
Development of a cyclosporin A derivative with excellent anti-hepatitis C virus potency
Fu, Jiping,Becker, Christopher,Cao, Li,Capparelli, Michael,Denay, Regis,Fujimoto, Roger,Gai, Yu,Gao, Zhaobo,Guenat, Christian,Karur, Subramanian,Kim, Hongyong,Li, Weikuan,Li, Xiaolin,Li, Wei,Lochmann, Thomas,Lu, Amy,Lu, Peichao,Luneau, Alexandre,Meier, Nicole,Mergo, Wosenu,Ng, Simon,Parker, David,Peng, Yunshan,Riss, Bernard,Rivkin, Alexey,Roggo, Silvio,Schroeder, Harald,Schuerch, Friedrich,Simmons, Robert L.,Sun, Feng,Sweeney, Zachary K.,Tjandra, Meiliana,Wang, Michael,Wang, Ruidong,Weiss, Andrew H.,Wenger, Nicolas,Wu, Quanbing,Xiong, Xin,Xu, Su,Xu, Wenjian,Yifru, Aregahegn,Zhao, Jibin,Zhou, Jianguang,Zürcher, Christian,Gallou, Fabrice
, p. 957 - 969 (2018)
Synthetic modification of cyclosporin A at P3-P4 positions led to the discovery of NIM258, a next generation cyclophilin inhibitor with excellent anti-hepatitis C virus potency, with decreased transporter inhibition, and pharmacokinetics suitable for coad
SYNTHESIS OF (2S,3R,4R)-4,5-DIHYDROXYISOLEUCINE AND DERIVATIVES
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Page/Page column 23-24, (2019/10/19)
The invention relates to a method for the preparation of a 4,5-dihydroxyisoleucine derivative comprising the steps of asymmetric Claisen rearrangement of a Z-aminocrotyl-glycin ester and subsequent kinetic resolution of the product diastereomer mix by acylase, and subsequent Sharpless dihydroxylation of the resulting 2-amino-3-methylpent-4-enoicacid derivative.
Pd(II)-Catalyzed [4 + 2] Heterocyclization Sequence for Polyheterocycle Generation
Glaisyer, Elizabeth L.,Watt, Michael S.,Booker-Milburn, Kevin I.
supporting information, p. 5877 - 5880 (2018/09/25)
A new Pd(II)-catalyzed cascade sequence for the formation of polyheterocycles, from simple starting materials, is reported. The sequence is applicable to both indole and pyrrole substrates, and a range of substituents are tolerated. The reaction is thought to proceed by a Pd(II)-catalyzed C-H activated Heck reaction followed by a second Pd(II)-catalyzed aza-Wacker reaction with two Cu(II)-mediated Pd(0) turnovers per sequence. The sequence can be considered a formal [4 + 2] heterocyclization.
The: Ortho -substituent on 2,4-bis(trifluoromethyl)phenylboronic acid catalyzed dehydrative condensation between carboxylic acids and amines
Wang, Ke,Lu, Yanhui,Ishihara, Kazuaki
supporting information, p. 5410 - 5413 (2018/05/30)
2,4-Bis(trifluoromethyl)phenylboronic acid is a highly effective catalyst for dehydrative amidation between carboxylic acids and amines. Mechanistic studies suggest that a 2:2 mixed anhydride is expected to be the only active species, and the ortho-substituent of boronic acid plays a key role in preventing the coordination of amines to the boron atom of the active species, thus accelerating the amidation. This catalyst works for α-dipeptide synthesis.
Synthesis of chiral TFA-protected α-amino aryl-ketone derivatives with friedel-crafts acylation of α-amino acid n-hydroxysuccinimide ester
Tachrim, Zetryana Puteri,Oida, Kazuhiro,Ikemoto, Haruka,Ohashi, Fumina,Kurokawa, Natsumi,Hayashi, Kento,Shikanai, Mami,Sakihama, Yasuko,Hashidoko, Yasuyuki,Hashimoto, Makoto
supporting information, (2017/11/07)
Chiral N-protected α-amino aryl-ketones are one of the useful precursors used in the synthesis of various biologically active compounds and can be constructed via Friedel-Crafts acylation of N-protected α-amino acids. One of the drawbacks of this reaction
Unified mild reaction conditions for C2-selective Pd-catalysed tryptophan arylation, including tryptophan-containing peptides
Reay, Alan J.,Williams, Thomas J.,Fairlamb, Ian J. S.
, p. 8298 - 8309 (2015/08/03)
Pd-mediated C-H bond functionalisation protocols have been designed and developed on tryptophan derivatives and tryptophan-containing peptides. The examination of different arylation reactions (three sets of different conditions A-C), all of which are notable for their low temperatures (≤40°C), allowed identification of unified and complementary synthetic approaches toward a series of functionalised tryptophan-containing products. Tryptophan-containing peptides demonstrated to be susceptible to aromatic oxidation were successfully and selectively modified through the application of diaryliodonium salts in good yields.
PROCESS FOR THE PREPARATION OF HYPERPOLARIZED CARBOXYLATE COMPOUNDS
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Page/Page column 38, (2015/05/19)
The present invention relates to a process for the preparation of aqueous solutions of [1-13C]-hyperpolarized carboxylate containing molecules of diagnostic interest that comprises parahydrogenating with molecular parahydrogen unsaturated alkenyl or alkynyl esters of the concerned 13C- carboxylate molecules.