An Alternative Synthesis of Some Carbohydrate α-Amino Acids

2004 ◽  
Vol 57 (1) ◽  
pp. 25 ◽  
Author(s):  
Grant S. Forman ◽  
Adrian Scaffidi ◽  
Robert V. Stick
Keyword(s):  
Amino Acids ◽  
Sodium Azide ◽  
Subsequent Treatment ◽  
Amino Ester ◽  
Alternative Synthesis ◽  
Tertiary Alcohols ◽  
Amino Esters

Several carbohydrate ketones have been converted into their trichloromethyl-branched tertiary alcohols. A subsequent treatment of these alcohols under Corey–Link conditions (base, sodium azide, methanol) has given rise to α-azido esters, transformable into azido acids, amino esters, and amino acids. An amino ester and an azido acid have been coupled to form a dipeptide.

The Synthesis of Carbohydrate α-Amino Acids Utilizing the Corey - Link Reaction

2004 ◽  
Vol 57 (8) ◽  
pp. 723 ◽  
Author(s):  
Adrian Scaffidi ◽  
Brian W. Skelton ◽  
Robert V. Stick ◽  
Allan H. White
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Single Crystal ◽  
Sodium Azide ◽  
Similar Sequence ◽  
X Ray ◽  
Tertiary Alcohols ◽  
Amino Esters

Various carbohydrate ketones (uloses) have been treated with chloroform under strongly basic conditions to yield trichloromethyl tertiary alcohols. These alcohols, when subjected to the conditions of the modified Corey–Link reaction (sodium azide and 1,8-diazabicyclo[5.4.0]undec-7-ene in methanol), generally gave the expected azido ester with complete stereocontrol. Subsequent transformations on these azido esters provided amino esters, azido acids, and, in one case, the amino acid. A similar sequence applied to a protected d-glucono-1,5-lactone was only partly successful. Single-crystal X-ray structures are reported for 1,2:5,6-di-O-isopropylidene-3-C-trichloromethyl-α-d-allose, (3S)-3-C-azido-3-C-carboxy-3-deoxy-1,2:5,6-di-O-isopropylidene-α-d-ribo-hexose, 1,2:5,6-di-O-cyclohexylidene-3-C-trichloromethyl-α-d-gulose, (3S)-3-C-amino-1,2:5,6-di-O-cyclohexylidene-3-deoxy-3-C-methoxycarbonyl-α-d-xylo-hexose, methyl 2-O-benzyl-4,6-O-benzylidene-3-C-trichloromethyl-α-d-alloside, methyl (2S)-2-C-azido-3-O-benzyl-4,6-O-benzylidene-2-deoxy-2-C-methoxycarbonyl-α-d-arabino-hexoside, methyl 2,3-di-O-benzyl-6-deoxy-4-C-trichloromethyl-β-d-galactoside, 3,4,5,7-tetra-O-benzyl-1,1,1-trichloro-1-deoxy-α-d-gluco-hept-2-ulose, and 5-O-benzyl-1,2-O-isopropylidene-3-C-trichloromethyl-α-d-ribose.

scholarly journals Constrained Dipeptide Surrogates: 5- and 7-Hydroxy Indolizidin-2-one Amino Acid Synthesis from Iodolactonization of Dehydro-2,8-diamino Azelates

Molecules ◽  
2021 ◽  
Vol 27 (1) ◽  
pp. 67
Author(s):  
Ramakotaiah Mulamreddy ◽  
William D. Lubell
Keyword(s):  
Amino Acids ◽  
Acid Synthesis ◽  
Ring System ◽  
Dihedral Angles ◽  
Type Ii ◽  
Amino Ester ◽  
Amino Acid Synthesis ◽  
X Ray ◽  
Amino Esters ◽  
Peptide Mimicry

The constrained dipeptide surrogates 5- and 7-hydroxy indolizidin-2-one N-(Boc)amino acids have been synthesized from L-serine as a chiral educt. A linear precursor ∆4-unsaturated (2S,8S)-2,8-bis[N-(Boc)amino]azelic acid was prepared in five steps from L-serine. Although epoxidation and dihydroxylation pathways gave mixtures of hydroxy indolizidin-2-one diastereomers, iodolactonization of the ∆4-azelate stereoselectively delivered a lactone iodide from which separable (5S)- and (7S)-hydroxy indolizidin-2-one N-(Boc)amino esters were synthesized by sequences featuring intramolecular iodide displacement and lactam formation. X-ray analysis of the (7S)-hydroxy indolizidin-2-one N-(Boc)amino ester indicated that the backbone dihedral angles embedded in the bicyclic ring system resembled those of the central residues of an ideal type II’ β-turn indicating the potential for peptide mimicry.

scholarly journals Stereoselective synthesis of perillaldehyde-based chiral β-amino acid derivatives through conjugate addition of lithium amides

2014 ◽  
Vol 10 ◽  
pp. 2738-2742 ◽  
Author(s):  
Zsolt Szakonyi ◽  
Reijo Sillanpää ◽  
Ferenc Fülöp
Keyword(s):  
Amino Acids ◽  
Stereoselective Synthesis ◽  
Minor Component ◽  
Conjugate Addition ◽  
Building Blocks ◽  
Major Product ◽  
Amino Ester ◽  
Chiral Amine ◽  
Amino Esters ◽  
Lithium Amides

The Michael addition of dibenzylamine to (+)-tert-butyl perillate (3) and to (+)-tert-butyl phellandrate (6), derived from (S)-(−)-perillaldehyde (1), resulted in diastereomeric β-amino esters 7A–D in a moderately stereospecific reaction in a ratio of 76:17:6:1. After separation of the diastereoisomers, the major product, cis isomer 7A, was quantitatively isomerized to the minor component, trans-amino ester 7D. All four isomers were transformed to the corresponding β-amino acids 10A–D, which are promising building blocks for the synthesis of β-peptides and 1,3-heterocycles in three steps. The steric effects of the isopropyl group at position 4 and of the α-methyl substituent of (R)-N-benzyl-N-α-methylbenzylamine on the reactivity were also studied and, upon application of a chiral amine, excellent stereoselectivity of the conjugate addition was observed. Amino ester 11 was obtained as a single product and transformed to the corresponding amino acids 10A and 10D in good yields on the gram scale.

Exogenous Directing Group Free, Ligand-Enabled gamma-C(sp3)–H Arylation of Free Primary Aliphatic Amines and α-Amino Esters

2019 ◽  
Author(s):  
Yongzheng Ding ◽  
Shuai Fan ◽  
Xiaoxi Chen ◽  
yuzhen gao ◽  
Gang Li
Keyword(s):  
Amino Acids ◽  
Large Scale ◽  
Free Ligand ◽  
Aliphatic Amines ◽  
Rapid Synthesis ◽  
Amino Esters ◽  
Directing Group ◽  
Large Scale Synthesis ◽  
Primary Aliphatic Amines

A Pdᴵᴵ-catalyzed, ligand-enabled gamma-C(sp3)–H arylation of free primary aliphatic amines and amino esters without using an exogenous directing group is reported. This reaction is compatible with unhindered free aliphatic amines, and it is also be applicable to the rapid synthesis of biologically and synthetically valuable unnatural α-amino acids. Large scale synthesis is also feasible using this method.<br>

Coupling of Steroid O-(Carboxymethyl)oxime Derivatives with Amino Alcohols

1996 ◽  
Vol 61 (2) ◽  
pp. 288-297 ◽  
Author(s):  
Vladimír Pouzar ◽  
Ivan Černý
Keyword(s):  
Amino Acids ◽  
Hydroxy Group ◽  
Building Blocks ◽  
Amino Alcohols ◽  
New Approach ◽  
Alternative Synthesis ◽  
Oxime Derivatives ◽  
A Chain ◽  
Derivatives Of

New approach to the preparation of steroids with connecting bridge, based on an O-carboxymethyloxime (CMO) structure, and with terminal hydroxy group, is presented. 17-CMO derivatives of 3β-acetoxy- and 3β-methoxymethoxyandrost-5-en-17-one were condensed with α,ω-amino alcohols to give derivatives with a chain of seven to nine atoms. After THP-protection, these compounds were converted to 3-keto-4-ene derivatives. An alternative synthesis consisted in transformation of 17-CMO derivatives with bonded amino acids by reduction of the terminal carboxyl. The resulting compounds were designed as building blocks for the preparation of bis-haptens for sandwich immunoassays.

scholarly journals Straightforward synthesis of enantiomerically pure 1,2,3-triazoles derived from amino esters

2018 ◽  
Vol 16 (17) ◽  
pp. 3168-3176 ◽  
Author(s):  
Gastón Silveira-Dorta ◽  
Sampad Jana ◽  
Lucie Borkova ◽  
Joice Thomas ◽  
Wim Dehaen
Keyword(s):  
Amino Acids ◽  
Enantiomerically Pure ◽  
Triazole Derivatives ◽  
Amino Esters ◽  
Good Yielding ◽  
Derivatives Of

An easy, good-yielding access to functionalized enantiomerically pure 1,2,3-triazole derivatives of amino acids using commercially available ketones and amino esters is described.

Festphasensynthese von Muramyldipeptiden an isomeren Trialkoxybenzylamin-Harzen / Solid Phase Synthesis of Muramyl Dipeptides on Isomeric Trialkoxybenzylamine Resins

1998 ◽  
Vol 53 (7) ◽  
pp. 753-764 ◽  
Author(s):  
Hans-Jürgen Kohlbaua ◽  
Jochen Tschakert ◽  
Raed A. Al-Qawasmeh ◽  
Tanveer Ahmad Nizamì ◽  
Abdul Malik ◽  
...  
Keyword(s):  
Amino Acids ◽  
Trifluoroacetic Acid ◽  
Solid Phase Synthesis ◽  
Solid Phase ◽  
Subsequent Treatment ◽  
Phase Synthesis ◽  
Merrifield Resin

Abstract New isomeric trialkoxybenzylamine resins are developed coupling phthalimidomethyl-3,5-dimethoxyphenols to the Merrifield resin, followed by subsequent treatment with hydrazine. The generated benzylamine function allows DCC coupling w ith the carboxyl function of amino acids and peptides which are removed as amides after treatment with trifluoroacetic acid. These new trialkoxybenzylamine resins allow expeditious syntheses of peptide amides and glycopeptide amides as is demonstrated for muramyl peptides and analogues.

Phosphoramidate Derivatives of AZT as Inhibitors of HIV: Studies on the Carboxyl Terminus

1993 ◽  
Vol 4 (2) ◽  
pp. 97-101 ◽  
Author(s):  
C. McGuigan ◽  
R. N. Pathirana ◽  
S. S.-M. Choi ◽  
D. Kinchington ◽  
T. J. O'Connor
Keyword(s):  
Amino Acids ◽  
Biological Activity ◽  
Carboxyl Terminus ◽  
Amino Ester ◽  
Carboxy Terminus ◽  
Free Nucleotides ◽  
Derivatives Of ◽  
Anti Hiv ◽  
Ester Lead

Novel phosphoramidate derivatives of the anti-HIV nucleoside analogue AZT have been prepared by phosphorochloridate chemistry. These materials carry carboxy-protected, amino acids, and are designed to act as membrane-soluble prodrugs of the bio-active free nucleotides. In vitro evaluation revealed the compounds to have a pronounced, selective antiviral activity. In particular, variation in the carboxy terminus region is studied. For alkyl phosphates small changes in the structure of the amino ester lead to marked changes in biological activity. However, for analogous aryl phosphates there is little dependence on the structure of the ester. This suggests a different mechanism of action for these two categories of phosphate prodrug.

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