Unnatural Amino Acids

  title={Unnatural Amino Acids},
  author={Loredano Pollegioni and Stefano de Servi},
  booktitle={Methods in Molecular Biology},
Ammonia-lyases catalyze a wide range of processes leading to , -unsaturated compounds by elimination of ammonia. In this chapter, ammonia-lyases are reviewed with major emphasis on their synthetic applications in stereoselective preparation of unnatural amino acids. Besides the synthesis of various unnatural -amino acids with the aid of phenylalanine ammonia-lyases (PALs) utilizing the 3,5-dihydro5-methylidene-4H-imidazol-4-one (MIO) prosthetic groups, the biotransformations leading to various… Expand
Asymmetric Synthesis of Protected Unnatural α-Amino Acids via Enantioconvergent Nickel-Catalyzed Cross-Coupling.
It is established that a chiral catalyst based on nickel can achieve the enantioconvergent coupling of readily available racemic alkyl electrophiles with a wide variety ofAlkylzinc reagents (1:1.1 ratio) to afford protected unnatural α-amino acids in good yield and ee. Expand
General Synthesis of Amino Acid Salts from Amino Alcohols and Basic Water Liberating H2.
An atom-economical and environmentally friendly method to transform amino alcohols to amino acid salts using just basic water, without the need of pre-protection or added oxidant, catalyzed by aExpand
Site-Selective Cu-Catalyzed Alkylation of α-Amino Acids and Peptides toward the Assembly of Quaternary Centers.
The CuI -catalyzed selective α-alkylation of α-amino acid and peptide derivatives with 2-alkyl-1,3-dioxolanes is reported. This oxidative coupling is distinguished by its site-specificity, highExpand
Synthesis of β- and γ-hydroxy α-amino acids via enzymatic kinetic resolution and cyanate-to-isocyanate rearrangement.
A new strategy for stereoselective preparation of all four isomers of β- and γ-hydroxy α-amino acids is presented, based on enzymatic kinetic resolution and cyanate-to-isocyanate rearrangement as key steps. Expand
Advances in Enzymatic Synthesis of D-Amino Acids
The aims of this review are to report the advances in synthesis of D-AAs gathered in the past few years based on five main classes of enzymes, and to improve the intrinsic atomic economy and cost-effectiveness. Expand
Pd-Catalyzed Asymmetric Hydroalkylation of 1,3-Dienes: Access to Unnatural α-Amino Acid Derivatives Containing Vicinal Quaternary and Tertiary Stereogenic Centers.
The synthetic utility of the current methodology was demonstrated through product transformations to access other biologically important compounds such as chiral β-amino alcohol and α-quaternary cyclic α-aminos acid derivatives. Expand
Formation of amide bond catalyzed by lipase in aqueous phase for peptide synthesis
Abstract A dipeptide N -acetyl- l -phenylalanyl- l -tyrosinamide ( N -Ac-Phe-Tyr-NH 2 ), with angiotensin I converting enzyme (ACE) inhibitor activity, was synthesized via porcine pancreatic lipaseExpand
Enantioselective Fluorescent Recognition of Amino Acids by Amide Formation: An Unusual Concentration Effect.
It was found that the amino acid-TBA salts can act as nucleophiles to cleave the perfluoroalkyl group off of the ketones to form the corresponding amides at room temperature in DMSO. Expand
On the Mechanism of Cross-Dehydrogenative Couplings between N-Aryl Glycinates and Indoles: A Computational Study.
Key information regarding the role of the N-aryl group and free NH motif within the reaction outcome has been gained, which may set the stage for further developments in this field of expertise. Expand
An approach to asymmetric synthesis of β-aryl alanines by Pd(0)-catalyzed cross-coupling and cyanate-to-isocyanate rearrangement
A new method for the asymmetric synthesis of β-aryl alanines is reported. The developed strategy is based on Pd(0)-catalyzed cross-coupling of chiral allyl alcohols with arylboronic acids followed byExpand


Synthesis of new Cα-tetrasubstituted α-amino acids
Although such aldehydes are prone to give aldol products under the reaction conditions used, the group was able to obtain the target cyclic amino acids in low to moderate yields and in some cases with good diastereoselectivity. Expand
Enhancing the utility of unnatural amino acid synthetases by manipulating broad substrate specificity.
It is demonstrated that the unnatural synthetases can be permissive to many unnatural amino acid substrates and can be converted into a permissive l-4-benzoylphenylalanine synthetase with a single mutation without compromising fidelity. Expand
Addition of a photocrosslinking amino acid to the genetic code of Escherichia coli
An orthogonal aminoacyl-tRNA synthetase/tRNA pair is evolved that makes possible the in vivo incorporation of p-benzoyl-l-phenylalanine into proteins in Escherichia coli in response to the amber codon, TAG. Expand
An Unnatural Amino Acid that Mimics a Tripeptide β-Strand and Forms β-Sheetlike Hydrogen-Bonded Dimers
Unnatural amino acid 2 (5-HO2CCONH-2-MeO-C6H3-CONHNH2) duplicates the hydrogen-bonding functionality of one edge of a tripeptide β-strand. It is composed of hydrazine, 5-amino-2-methoxybenzoic acid,Expand
Synthesis of novel unnatural amino acid as a building block and its incorporation into an antimicrobial peptide.
  • J. Oh, K. Lee
  • Medicine, Chemistry
  • Bioorganic & medicinal chemistry
  • 1999
The results indicated that the unnatural amino acids synthesized in this study could be used not only as a novel building block for combinatorial libraries of antimicrobial peptides, but also for structure-activity relationship studies about antimicrobialpeptides. Expand
De novo design of selective antibiotic peptides by incorporation of unnatural amino acids.
To develop antimicrobial peptides exhibiting increased potency and selectivity against Gram positive, Gram negative, and Mycobacterium bacteria coupled with reduced hemolytic activity, peptides containing unnatural amino acids have been designed, synthesized, and evaluated. Expand
Addition of p-azido-L-phenylalanine to the genetic code of Escherichia coli.
We report the selection of a new orthogonal aminoacyl tRNA synthetase/tRNA pair for the in vivo incorporation of a photocrosslinker, p-azido-l-phenylalanine, into proteins in response to the amberExpand
A novel beta-turn mimic useful for mapping the unknown topology of peptide receptors.
Ethers of cis or trans D-4-hydroxyproline (Hype), adjacent to octahydroindole-carboxylic acid (Oic), introduce a beta-turn into the backbone of peptides when positioned respectively at the i+1 andExpand
Adding new chemistries to the genetic code.
The development of new orthogonal aminoacyl-tRNA synthetase/tRNA pairs has led to the addition of approximately 70 unnatural amino acids to the genetic codes of Escherichia coli, yeast, and mammalian cells, which provide new opportunities to generate proteins with enhanced or novel properties and probes of protein structure and function. Expand
A Repertoire of Novel Antibacterial Diastereomeric Peptides with Selective Cytolytic Activity*
  • Z. Oren, Jiang Hong, Y. Shai
  • Biology, Medicine
  • The Journal of Biological Chemistry
  • 1997
The data reveal that modulating hydrophobicity and positive charge is sufficient to confer antibacterial activity and cell selectivity, and proposes a new strategy for the design of a repertoire of short, simple, and easily manipulated antibacterial peptides as potential drugs in the treatment of infectious diseases. Expand