1844-40-2Relevant academic research and scientific papers
2-Keto-3-Deoxy-l-Rhamnonate Aldolase (YfaU) as Catalyst in Aldol Additions of Pyruvate to Amino Aldehyde Derivatives
Hernández, Karel,Gómez, Ariadna,Joglar, Jesús,Bujons, Jordi,Parella, Teodor,Clapés, Pere
, p. 2090 - 2100 (2017/06/23)
4-Hydroxy-2-keto acid derivatives are versatile building blocks for the synthesis of amino acids, hydroxy carboxylic acids and chiral aldehydes. Pyruvate aldolases are privileged catalysts for a straightforward access to this class of keto acid compounds. In this work, a Class II pyruvate aldolase from Escherichia coli K-12, 2-keto-3-deoxy-l-rhamnonate aldolase (YfaU), was evaluated for the synthesis of amino acid derivatives of proline, pipecolic acid, and pyrrolizidine-3-carboxylic acid. The aldol addition of pyruvate to N-protected amino aldehydes was the key enzymatic aldol addition step followed by catalytic intramolecular reductive amination. The corresponding N-Cbz-amino-4-hydroxy-2-keto acid (Cbz=benzyloxycarbonyl) precursors were obtained in 51–95% isolated yields and enantioselectivity ratios from 26:74 to 95:5, with chiral α-substituted N-Cbz-amino aldehydes. (S)-N-Cbz-amino aldehydes gave aldol adducts with preferentially (R)-configuration at the newly formed stereocenter, whereas the contrary is true for (R)-N-Cbz-amino aldehydes. Addition reactions to achiral amino aldehydes rendered racemic aldol adducts. Molecular models of the pre-reaction ternary complexes YfaU-pyruvate enolate-acceptor aldehyde were constructed to explain the observed stereochemical outcome of the reactions. Catalytic reductive amination of the aldol adducts yielded 4-hydroxy-2-pipecolic acid, and unprecedented C-5 substituted 4-hydroxyproline and pyrrolizidine-3-carboxylic acid derivatives. (Figure presented.).
AN ENANTIOSELECTIVE PROCESS FOR THE SYNTHESIS OF (2S,4R)-4-HYDROXYPIPECOLIC ACID
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Page/Page column 24; 25, (2016/08/23)
The present invention relates to an improved process for synthesis of 4-hydroxy pipecolic acid. The present invention relates to an improved enantioselective process for the synthesis of (2S,4R)-4-hydroxypipecolic acid via Co(III) (salen)-catalyzed two stereocentered Hydrolytic Kinetic Resolution (HKR) of racemic 1,3-azido epoxide with good yields and high optical purity without any protecting groups. 10 31
Ulleungamides A and B, Modified α,β-Dehydropipecolic Acid Containing Cyclic Depsipeptides from Streptomyces sp. KCB13F003
Son, Sangkeun,Ko, Sung-Kyun,Jang, Mina,Lee, Jae Kyoung,Ryoo, In-Ja,Lee, Jung-Sook,Lee, Kyung Ho,Soung, Nak-Kyun,Oh, Hyuncheol,Hong, Young-Soo,Kim, Bo Yeon,Jang, Jae-Hyuk,Ahn, Jong Seog
supporting information, p. 4046 - 4049 (2015/09/01)
Two novel cyclic depsipeptides, ulleungamides A (1) and B (2), were isolated from cultures of terrestrial Streptomyces sp. Their structures were determined by analyses of spectroscopic data and various chemical transformations, including modified Mosher's method, advanced Marfey's method, PGME, GITC derivatizations, and Snatzke's method. Ulleungamides were determined to be a new class of peptides bearing unprecedented units, such as 5-hydroxy-6-methyl-2,3-dehydropipecolic acid, 4,5-dihydroxy-6-methyl-2,3-dehydropipecolic acid, and amino-linked 2-isopropylsuccinic acid. Ulleungamide A displayed growth inhibitory activity against Staphylococcus aureus and Salmonella typhimurium without cytotoxicity.
A concise and diastereoselective synthesis of piperidine and indolizidine alkaloids via aza-Prins cyclization
Reddy, Basi V. Subba,Chaya, Dudhmal N.,Yadav, Jhillu S.,Gree, Rene
experimental part, p. 297 - 303 (2012/03/26)
The synthesis of 2-substituted and 2,4-disubstituted piperidine alkaloids such as (±)-coniine, (±)-hydroxypipecolic acid, (±)-pipecolic acid, (±)-coniceine, and (±)-4-hydroxy-2- hydroxy-methyl piperidine have been accomplished in a highly diastereo-selective manner by employing aza-Prins cyclization as a key step to construct the piperidine core of these alkaloids. Georg Thieme Verlag Stuttgart · New York.
Validation of high-affinity binding sites for succinic acid through distinguishable binding of gamma-hydroxybutyric acid receptor-specific NCS 382 antipodes
Molnar, Tuende,Visy, Julia,Simon, Agnes,Moldvai, Istvan,Temesvari-Major, Eszter,Doernyei, Gabor,Fekete, Erzsebet Kutine,Kardos, Julianna
supporting information; experimental part, p. 6290 - 6292 (2009/07/18)
Gamma-hydroxybutyric acid (GHB) binding to multiple sites for the tricarboxylic acid cycle intermediate succinic acid (SUC) has been disclosed recently. In order to better characterize these targets, distinguishable binding of GHB receptor-specific NCS 38
Use of hydrolases for the synthesis of cyclic amino acids
Lloyd, Richard C.,Lloyd, Michael C.,Smith, Mark E. B.,Holt, Karen E.,Swift, Jonathan P.,Keene, Philip A.,Taylor, Stephen J. C.,McCague, Raymond
, p. 717 - 728 (2007/10/03)
The synthesis of several cyclic amino acids that have all the necessary structural features to make them ideal scaffolds for use in medicinal chemistry is described. A key step in each synthesis is the use of hydrolase enzymes to define a chiral centre. I
Synthesis of Enantiopure 4-Hydroxypipecolate and 4-Hydroxylysine Derivatives from a Common 4,6-Dioxopiperidinecarboxylate Precursor
Marin,Didierjean,Aubry,Casimir,Briand,Guichard
, p. 130 - 141 (2007/10/03)
tert-Butyl 2-substituted 4,6-dioxo-1-piperidinecarboxylates 4 have been prepared in good yield starting from Boc-Asp-OtBu and other β-amino acids. By analogy with chiral tetramic acids, their reduction by NaBH4 in CH2Cl2/AcOH afforded the corresponding cis-4-hydroxy δ-lactams in good yield and stereoselectivity (68-98% de). In the absence of the A(1,3) strain (reduction of 6-substituted 2,4-dioxo-1-piperidines 7), the cis-4-hydroxy isomer was still obtained as the major product but the de values were consistently lower. 4-Hydroxy-6-oxo- 1,2-piperidinedicarboxylate 2a, readily accessible from Boc-Asp-OtBu (three steps, 63% overall yield), has proven to be an excellent building block for the synthesis of cis- and trans-4-hydroxypipecolates 17 and 24 (52 and 36% overall yield, respectively) and for the synthesis of a protected 4-hydroxylysine derivative 29 (41% overall yield).
6-Bromomethyl-4H-1,3-dioxin: A versatile bromomethyl vinyl ketone equivalent for heterocycle and carbocycle construction
Greshock, Thomas J.,Funk, Raymond L.
, p. 754 - 755 (2007/10/03)
6-Bromomethyl-4H-1,3-dioxin has been prepared in three steps from allyl iodide. A variety of enolates were then alkylated with this bromide. The resulting 6-alkyl-4H-1,3-dioxins were either subjected to further multistep transformations and/or heated to e
trans-6-Aminocyclohept-3-enols, a new designed polyfunctionalized chiral building block for the asymmetric synthesis of 2-substituted-4-hydroxypiperidines.
Celestini, Paolo,Danieli, Bruno,Lesma, Giordano,Sacchetti, Alessandro,Silvani, Alessandra,Passarella, Daniele,Virdis, Andrea
, p. 1367 - 1370 (2007/10/03)
trans-6-Aminocyclohept-3-enols 18 and ent-18 are new designed polyfunctionalized chiral building blocks for piperidine alkaloids synthesis and are prepared in high yields from the enzymatically derived cyclohept-3-ene-1,6-diol monoacetate (-)-8. Efficient highly enantioselective syntheses of cis-4-hydroxypipecolic acid (1) and piperidines 3 and 4, in both enantiomeric forms, are described. [reaction: see text]
Asymmetric syntheses of enantiopure 4-substituted pipecolic acid derivatives
Agami, Claude,Bisaro, Fabrice,Comesse, Sebastien,Guesne, Sebastien,Kadouri-Puchot, Catherine,Morgentin, Remy
, p. 2385 - 2389 (2007/10/03)
(2R,4R)-4-Methylpipecolic acid and (2S,4R)-4-hydroxypipecolic acid, two biologically active amino acids, were synthesized using the same strategy. A third amino acid, obtained in a protected form, was also obtained in the same way. The key step of these syntheses involves an intramolecular eneiminium cyclization which occurs with complete stereoselectivity. The resulting exocyclic double bond can react in a diastereoselective way to afford pure lactones, which can then be efficiently converted into the amino acids.
