1
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Saunders GJ, Spring SA, Jayawant E, Wilkening I, Roesner S, Clarkson GJ, Dixon AM, Notman R, Shipman M. Synthesis and Functionalization of Azetidine-Containing Small Macrocyclic Peptides. Chemistry 2024; 30:e202400308. [PMID: 38488326 DOI: 10.1002/chem.202400308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Indexed: 04/11/2024]
Abstract
Cyclic peptides are increasingly important structures in drugs but their development can be impeded by difficulties associated with their synthesis. Here, we introduce the 3-aminoazetidine (3-AAz) subunit as a new turn-inducing element for the efficient synthesis of small head-to-tail cyclic peptides. Greatly improved cyclizations of tetra-, penta- and hexapeptides (28 examples) under standard reaction conditions are achieved by introduction of this element within the linear peptide precursor. Post-cyclization deprotection of the amino acid side chains with strong acid is realized without degradation of the strained four-membered azetidine. A special feature of this chemistry is that further late-stage modification of the resultant macrocyclic peptides can be achieved via the 3-AAz unit. This is done by: (i) chemoselective deprotection and substitution at the azetidine nitrogen, or by (ii) a click-based approach employing a 2-propynyl carbamate on the azetidine nitrogen. In this way, a range of dye and biotin tagged macrocycles are readily produced. Structural insights gained by XRD analysis of a cyclic tetrapeptide indicate that the azetidine ring encourages access to the less stable, all-trans conformation. Moreover, introduction of a 3-AAz into a representative cyclohexapeptide improves stability towards proteases compared to the homodetic macrocycle.
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Affiliation(s)
- George J Saunders
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, U.K
| | - Sam A Spring
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, U.K
| | - Eleanor Jayawant
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, U.K
| | - Ina Wilkening
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, U.K
| | - Stefan Roesner
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, U.K
| | - Guy J Clarkson
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, U.K
| | - Ann M Dixon
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, U.K
| | - Rebecca Notman
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, U.K
| | - Michael Shipman
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, U.K
- The Palatine Centre, Stockton Road, Durham, DH1 3LE, U.K
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2
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Diaz DB, Rowshanpour R, Saunders GJ, Dudding T, Yudin AK. The Role of Attractive Non-Covalent Interactions in Peptide Macrocyclization. J Org Chem 2024; 89:1483-1491. [PMID: 38217516 DOI: 10.1021/acs.joc.3c02084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2024]
Abstract
The efficiency of macrocyclization reactions relies on the appropriate conformational preorganization of a linear precursor, ensuring that reactive ends are in spatial proximity prior to ring closure. Traditional peptide cyclization approaches that reduce the extent of terminal ion pairing often disfavor cyclization-conducive conformations and can lead to undesired cyclodimerization or oligomerization side reactions, particularly when they are performed without high dilution. To address this challenge, synthetic strategies that leverage attractive noncovalent interactions, such as zwitterionic attraction between chain termini during macrocyclization, offer a potential solution by reducing the entropic penalty associated with linear peptides adopting precyclization conformations. In this study, we investigate the role of (N-isocyanoimino)triphenylphosphorane (Pinc) in facilitating the cyclization of linear peptides into conformationally rigid macrocycles. The observed moderate diastereoselectivity is consistent with the preferential Si-facial addition of Pinc, where the isocyanide adds to the E-iminium ion on the same face as the l-proline amide group. The resulting peptide chain reveals that the activated phosphonium ylide of Pinc brings the reactive ends close together, promoting cyclization by enclosing the carboxylate within the interior of the pentapeptide and preventing the formation of byproducts. For shorter peptides with modified peptide backbones, the cyclization mechanism and outcome are redirected, as nucleophilic motifs such as thiazole and imidazole can covalently trap nitrilium intermediates. The isolation of the intermediate in the unproductive macrocyclization pathway, along with nuclear magnetic resonance and density functional theory studies, provides insights into heterocycle-dependent selectivity. The Pinc-driven macrocyclization process has generated diverse collections of cyclic molecules, and our models offer a comprehensive understanding of observed trends, facilitating the development of other heterocycle-forming macrocyclization reactions.
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Affiliation(s)
- Diego B Diaz
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Rozhin Rowshanpour
- Department of Chemistry, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - George J Saunders
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Travis Dudding
- Department of Chemistry, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| | - Andrei K Yudin
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
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3
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Wang T, Meng Q, Lin L, Yang L, Zhao W, Sun D. Self-assembled dehydropeptide nanocarrier as a delivery system for antitumor drug temozolomide. Bioorg Chem 2022; 124:105842. [PMID: 35512421 DOI: 10.1016/j.bioorg.2022.105842] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 03/12/2022] [Accepted: 04/23/2022] [Indexed: 12/20/2022]
Abstract
Stable molecular conformation and intermolecular forces are essential for peptide self-assembly. In this study, one novel dehydropeptide (DDP) monomer (Boc-(Z)Cα,β-ΔPhe-Gly-NHMe, DDP 1) was prepared; its conformation was confirmed to be more stable than the normal peptide 2 by nuclear magnetic resonance (NMR) and X-ray crystal diffraction experiments. DDP 1 was self-assembled to one novel dehydropeptide nanomaterial (DDPN 1). Fourier transform infrared (FTIR) spectroscopy results showed that hydrogen bonding was the main driving force of self-assembly. Electron microscope images displayed that the DDPN 1 fibers were longer and more stable than peptide 2 nanomaterials. Results of cell activity and enzyme hydrolysis proved that DDPN 1 had excellent biocompatibility and resistance to the enzymatic hydrolysis of protease K. Therefore, the DDPN 1 was used to load the antitumor drug temozolomide (TMZ). Due to intermolecular hydrogen bonds formed between TMZ and DDPN 1, TMZ-loaded DDPN 1 had a high percent entrapment efficiency (EE) of 83.72 ± 4.30% (n = 8) and a percent drug loading efficiency (LE) of 6.70 ± 0.34% (n = 8), and the half-life of TMZ-loaded DDPN 1 was 2.5-3 times longer than that of TMZ at pH 7. The in vitro cell viability results revealed that TMZ-loaded DDPN 1 exhibited higher antitumor activity (IC50 = 552.1 μM) against U118-MG than that of TMZ (IC50 = 1980.1 μM), possibly because that U118-MG cells uptook more TMZ from TMZ-loaded DDPN 1 than from free TMZ directly. This study is expected to inspire the design of biocompatible nanocarriers applied for anti-enzymatic hydrolysis in drug delivery systems.
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Affiliation(s)
- Tong Wang
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China
| | - Qian Meng
- Marine College, Shandong University at Weihai, Weihai, China
| | - Lan Lin
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China
| | - Li Yang
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China
| | - Wenjiao Zhao
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China; Marine College, Shandong University at Weihai, Weihai, China
| | - Dequn Sun
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China.
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4
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Moyá DA, Lee MA, Chanthakhoun JC, LeSueur AK, Joaquin D, Barfuss JD, Castle SL. Towards a streamlined synthesis of peptides containing α,β-dehydroamino acids. Tetrahedron Lett 2021; 74:153175. [PMID: 34176981 PMCID: PMC8224935 DOI: 10.1016/j.tetlet.2021.153175] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Investigation of a strategy to streamline the synthesis of peptides containing α,β-dehydroamino acids (ΔAAs) is reported. The key step involves generating the alkene moiety via elimination of a suitable precursor after it has been inserted into a peptide chain. This process obviates the need to prepare ΔAA-containing azlactone dipeptides to facilitate coupling of these residues. Z-dehydroaminobutyric acid (Z-ΔAbu) could be constructed most efficiently via EDC/CuCl-mediated dehydration of Thr. Formation of Z-ΔPhe by this or other dehydration methods was unsuccessful. Production of the bulky ΔVal residue could be accomplished by DAST-promoted dehydrations of β-OHVal or by DBU-triggered eliminations of sulfonium ions derived from penicillamine derivatives. However, competitive formation of an oxazoline byproduct remains problematic.
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Affiliation(s)
- Diego A Moyá
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA
| | - Michael A Lee
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA
| | - Joseph C Chanthakhoun
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA
| | - Austin K LeSueur
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA
| | - Daniel Joaquin
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA
| | - Jaden D Barfuss
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA
| | - Steven L Castle
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT 84602, USA
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5
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Parker PD, Hou X, Dong VM. Reducing Challenges in Organic Synthesis with Stereoselective Hydrogenation and Tandem Catalysis. J Am Chem Soc 2021; 143:6724-6745. [PMID: 33891819 DOI: 10.1021/jacs.1c00750] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Tandem catalysis enables the rapid construction of complex architectures from simple building blocks. This Perspective shares our interest in combining stereoselective hydrogenation with transformations such as isomerization, oxidation, and epimerization to solve diverse challenges. We highlight the use of tandem hydrogenation for preparing complex natural products from simple prochiral building blocks and present tandem catalysis involving transfer hydrogenation and dynamic kinetic resolution. Finally, we underline recent breakthroughs and opportunities for asymmetric hydrogenation.
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Affiliation(s)
- Patrick D Parker
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Xintong Hou
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Vy M Dong
- Department of Chemistry, University of California, Irvine, California 92697, United States
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6
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Raj M, Wills RD, Adebomi VT. Peptide Cyclization at High Concentration. Synlett 2020. [DOI: 10.1055/s-0040-1707165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The emergence of cyclic peptides as pharmaceuticals has led to an eruption of new methodologies for macrocyclization. However, the cyclization of peptides at high concentrations presents a challenge due to the production of side products like dimers and oligomers. This factor is more pronounced with the cyclization of peptides composed of fewer than seven amino acids, thus has created a need for a new synthetic strategy. Herein, we will elucidate a new chemoselective method termed ‘CyClick’ that works in an exclusively intramolecular fashion preventing the formation of commonly occurring side products such as dimers and oligomers, even at relatively high concentration.1 Introduction2 Known Methodologies3 Novel CyClick Chemistry4 Conclusion and Outlook
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Affiliation(s)
- Monika Raj
- Department of Chemistry and Biochemistry, Auburn University Auburn
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7
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Joaquin D, Lee MA, Kastner DW, Singh J, Morrill ST, Damstedt G, Castle SL. Impact of Dehydroamino Acids on the Structure and Stability of Incipient 3 10-Helical Peptides. J Org Chem 2019; 85:1601-1613. [PMID: 31730750 DOI: 10.1021/acs.joc.9b02747] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A comparative study of the impact of small, medium-sized, and bulky α,β-dehydroamino acids (ΔAAs) on the structure and stability of Balaram's incipient 310-helical peptide (1) is reported. Replacement of the N-terminal Aib residue of 1 with a ΔAA afforded peptides 2a-c that maintained the 310-helical shape of 1. In contrast, installation of a ΔAA in place of Aib-3 yielded peptides 3a-c that preferred a β-sheet-like conformation. The impact of the ΔAA on peptide structure was independent of size, with small (ΔAla), medium-sized (Z-ΔAbu), and bulky (ΔVal) ΔAAs exerting similar effects. The proteolytic stabilities of 1 and its analogs were determined by incubation with Pronase. Z-ΔAbu and ΔVal increased the resistance of peptides to proteolysis when incorporated at the 3-position and had negligible impact on stability when placed at the 1-position, whereas ΔAla-containing peptides degraded rapidly regardless of position. Exposure of peptides 2a-c and 3a-c to the reactive thiol cysteamine revealed that ΔAla-containing peptides underwent conjugate addition at room temperature, while Z-ΔAbu- and ΔVal-containing peptides were inert even at elevated temperatures. These results suggest that both bulky and more accessible medium-sized ΔAAs should be valuable tools for bestowing rigidity and proteolytic stability on bioactive peptides.
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Affiliation(s)
- Daniel Joaquin
- Department of Chemistry and Biochemistry , Brigham Young University , Provo , Utah 84602 , United States
| | - Michael A Lee
- Department of Chemistry and Biochemistry , Brigham Young University , Provo , Utah 84602 , United States
| | - David W Kastner
- Department of Chemistry and Biochemistry , Brigham Young University , Provo , Utah 84602 , United States
| | - Jatinder Singh
- Department of Chemistry and Biochemistry , Brigham Young University , Provo , Utah 84602 , United States
| | - Shardon T Morrill
- Department of Chemistry and Biochemistry , Brigham Young University , Provo , Utah 84602 , United States
| | - Gracie Damstedt
- Department of Chemistry and Biochemistry , Brigham Young University , Provo , Utah 84602 , United States
| | - Steven L Castle
- Department of Chemistry and Biochemistry , Brigham Young University , Provo , Utah 84602 , United States
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8
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Roesner S, Saunders GJ, Wilkening I, Jayawant E, Geden JV, Kerby P, Dixon AM, Notman R, Shipman M. Macrocyclisation of small peptides enabled by oxetane incorporation. Chem Sci 2019; 10:2465-2472. [PMID: 30881675 PMCID: PMC6385813 DOI: 10.1039/c8sc05474f] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 12/22/2018] [Indexed: 12/29/2022] Open
Abstract
Cyclic peptides are an important source of new drugs but are challenging to produce synthetically. We show that head-to-tail peptide macrocyclisations are greatly improved, as measured by isolated yields, reaction rates and product distribution, by substitution of one of the backbone amide C[double bond, length as m-dash]O bonds with an oxetane ring. The cyclisation precursors are easily made by standard solution- or solid-phase peptide synthesis techniques. Macrocyclisations across a range of challenging ring sizes (tetra-, penta- and hexapeptides) are enabled by incorporation of this turn-inducing element. Oxetane incorporation is shown to be superior to other established amino acid modifications such as N-methylation. The positional dependence of the modification on cyclisation efficiency is mapped using a cyclic peptide of sequence LAGAY. We provide the first direct experimental evidence that oxetane modification induces a turn in linear peptide backbones, through the observation of d NN (i, i + 2) and d αN (i, i + 2) NOEs, which offers an explanation for these improvements. For cyclic peptide, cLAGAY, a combination of NMR derived distance restraints and molecular dynamics simulations are used to show that this modification alters the backbone conformation in proximity to the oxetane, with the flexibility of the ring reduced and a new intramolecular H-bond established. Finally, we incorporated an oxetane into a cyclic pentapeptide inhibitor of Aminopeptidase N, a transmembrane metalloprotease overexpressed on the surface of cancer cells. The inhibitor, cCNGRC, displayed similar IC50 values in the presence or absence of an oxetane at the glycine residue, indicating that bioactivity is fully retained upon amide C[double bond, length as m-dash]O bond replacement.
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Affiliation(s)
- Stefan Roesner
- Department of Chemistry , University of Warwick , Gibbet Hill Road , Coventry , CV4 7AL , UK .
| | - George J Saunders
- Department of Chemistry , University of Warwick , Gibbet Hill Road , Coventry , CV4 7AL , UK .
| | - Ina Wilkening
- Department of Chemistry , University of Warwick , Gibbet Hill Road , Coventry , CV4 7AL , UK .
| | - Eleanor Jayawant
- Department of Chemistry , University of Warwick , Gibbet Hill Road , Coventry , CV4 7AL , UK .
| | - Joanna V Geden
- Department of Chemistry , University of Warwick , Gibbet Hill Road , Coventry , CV4 7AL , UK .
| | - Paul Kerby
- Department of Chemistry , University of Warwick , Gibbet Hill Road , Coventry , CV4 7AL , UK .
| | - Ann M Dixon
- Department of Chemistry , University of Warwick , Gibbet Hill Road , Coventry , CV4 7AL , UK .
| | - Rebecca Notman
- Department of Chemistry , University of Warwick , Gibbet Hill Road , Coventry , CV4 7AL , UK .
| | - Michael Shipman
- Department of Chemistry , University of Warwick , Gibbet Hill Road , Coventry , CV4 7AL , UK .
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9
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Le DN, Hansen E, Khan HA, Kim B, Wiest O, Dong VM. Hydrogenation catalyst generates cyclic peptide stereocentres in sequence. Nat Chem 2018; 10:968-973. [PMID: 30061616 DOI: 10.1038/s41557-018-0089-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 05/22/2018] [Indexed: 11/09/2022]
Abstract
Molecular recognition plays a key role in enzyme-substrate specificity, the regulation of genes, and the treatment of diseases. Inspired by the power of molecular recognition in enzymatic processes, we sought to exploit its use in organic synthesis. Here we demonstrate how a synthetic rhodium-based catalyst can selectively bind a dehydroamino acid residue to initiate a sequential and stereoselective synthesis of cyclic peptides. Our combined experimental and theoretical study reveals the underpinnings of a cascade reduction that occurs with high stereocontrol and in one direction around a macrocyclic ring. As the catalyst can dissociate from the peptide, the C to N directionality of the hydrogenation reactions is controlled by catalyst-substrate recognition rather than a processive mechanism in which the catalyst remains bound to the macrocycle. This mechanistic insight provides a foundation for the use of cascade hydrogenations.
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Affiliation(s)
- Diane N Le
- Department of Chemistry, University of California, Irvine, CA, USA
| | - Eric Hansen
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA
| | - Hasan A Khan
- Department of Chemistry, University of California, Irvine, CA, USA.,Department of Chemistry, University of Toronto, Toronto, ON, Canada
| | - Byoungmoo Kim
- Department of Chemistry, University of California, Irvine, CA, USA.,Department of Chemistry, University of Toronto, Toronto, ON, Canada
| | - Olaf Wiest
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, USA. .,Lab of Computational Chemistry and Drug Design, School of Chemical Biology and Biotechnology, Peking University, Shenzhen, China.
| | - Vy M Dong
- Department of Chemistry, University of California, Irvine, CA, USA.
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10
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Wołczański G, Lisowski M. A general method for preparation of N-Boc-protected or N-Fmoc-protected α,β-didehydropeptide building blocks and their use in the solid-phase peptide synthesis. J Pept Sci 2018; 24:e3091. [PMID: 29862598 DOI: 10.1002/psc.3091] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 04/24/2018] [Accepted: 05/02/2018] [Indexed: 12/14/2022]
Abstract
N-(tert-butyloxycarbonyl) or N-(9-fluorenylmethoxycarbonyl) dipeptides with C-terminal (Z)-α,β-didehydrophenylalanine (∆Z Phe), (Z)-α,β-didehydrotyrosine (∆Z Tyr), (Z)-α,β-didehydrotryptophan (∆Z Trp), (Z)-α,β-didehydromethionine (∆Z Met), (Z)-α,β-didehydroleucine (∆Z Leu), and (Z/E)-α,β-didehydroisoleucine (∆Z/E Ile) were synthesised from their saturated analogues via oxidation of intermediate 2,5-disubstituted-oxazol-5-(4H)-ones (also known as azlactones) with pyridinium tribromide followed by opening of the produced unsaturated oxazol-5-(4H)-one derivatives in organic-aqueous solution with a catalytic amount of trifluoroacetic acid or by a basic hydrolysis. In all cases, a very strong preference for Z isomers of α,β-didehydro-α-amino acid residues was observed except of the ΔIle, which was obtained as the equimolar mixture of Z and E isomers. Reasons for the (Z)-stereoselectivity and the increased stability of the aromatic α,β-didehydro-α-amino acid residue oxazol-5-(4H)-ones over the corresponding aliphatic ones are also discussed. It is the first use of such a procedure to synthesise peptides with the C-terminal unsaturated residues and a peptide with 2 consecutive ΔPhe residues. This approach is very effective especially in the synthesis of peptides with aliphatic α,β-didehydro-α-amino acid residues that are difficult to obtain by other methods. It allowed the first synthesis of the ∆Met residue. It is also more cost-effective and less laborious than other synthesis protocols. The dipeptide building blocks obtained were used in the solid-phase synthesis of model peptides on a polystyrene-based solid support. Peptides containing aromatic α,β-didehydro-α-amino acid residues were obtained with PyBOP or TBTU as a coupling agent with good yields and purities. In the case of aliphatic α,β-didehydro-α-amino acid residues, a good efficiency was achieved only with DPPA as a coupling agent.
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Affiliation(s)
- Grzegorz Wołczański
- Faculty of Chemistry, University of Wrocław, F. Joliot-Curie 14, 50-383, Wrocław, Poland
| | - Marek Lisowski
- Faculty of Chemistry, University of Wrocław, F. Joliot-Curie 14, 50-383, Wrocław, Poland
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11
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Curtin BH, Manoni F, Park J, Sisto LJ, Lam YH, Gravel M, Roulston A, Harran PG. Assembly of Complex Macrocycles by Incrementally Amalgamating Unprotected Peptides with a Designed Four-Armed Insert. J Org Chem 2018; 83:3090-3108. [DOI: 10.1021/acs.joc.7b02958] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Brice H. Curtin
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California 90095, United States
| | - Francesco Manoni
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California 90095, United States
| | - Jiyong Park
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California 90095, United States
| | - Luke J. Sisto
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California 90095, United States
| | - Yu-hong Lam
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California 90095, United States
| | - Michel Gravel
- Laboratory for Therapeutic Development, Rosalind and Morris Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Anne Roulston
- Laboratory for Therapeutic Development, Rosalind and Morris Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Patrick G. Harran
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California 90095, United States
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12
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Abstract
The development of efficient methods for the synthesis of cyclic peptides is of interest because of the many potential applications of this class of molecule. Pseudoprolines are derived from serine, threonine, and cysteine and can be used as traceless turn-inducers to facilitate the cyclization of a wide range of linear peptide precursors. The incorporation of a pseudoproline into the peptide to be cyclized generally results in a cyclization reaction that proceeds more quickly and with higher yield than that of an analogous sequence without the pseudoproline. Installation of a pseudoproline at the C-terminal position of a linear peptide sequence has also been shown to eliminate any epimerization of this residue during the reaction. Following pseudoproline-mediated cyclization, these turn-inducers can be removed on treatment with acid in a similar manner to other protecting groups to provide the native peptide sequence, and in the case of cysteine-derived pseudoprolines, the resulting cysteine can be readily converted into alanine through desulfurization. These traceless turn-inducers have been successfully used in the synthesis of cyclic peptides containing either serine, threonine, cysteine or alanine residues.
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13
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Jalan A, Kastner DW, Webber KGI, Smith MS, Price JL, Castle SL. Bulky Dehydroamino Acids Enhance Proteolytic Stability and Folding in β-Hairpin Peptides. Org Lett 2017; 19:5190-5193. [PMID: 28910115 PMCID: PMC6085080 DOI: 10.1021/acs.orglett.7b02455] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The bulky dehydroamino acids dehydrovaline (ΔVal) and dehydroethylnorvaline (ΔEnv) can be inserted into the turn regions of β-hairpin peptides without altering their secondary structures. These residues increase proteolytic stability, with ΔVal at the (i + 1) position having the most substantial impact. Additionally, a bulky dehydroamino acid can be paired with a d-amino acid (i.e., d-Pro) to synergistically enhance resistance to proteolysis. A link between proteolytic stability and peptide structure is established by the finding that a stabilized ΔVal-containing β-hairpin is more highly folded than its Asn-containing congener.
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Affiliation(s)
- Ankur Jalan
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, United States
| | - David W. Kastner
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, United States
| | - Kei G. I. Webber
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, United States
| | - Mason S. Smith
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, United States
| | - Joshua L. Price
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, United States
| | - Steven L. Castle
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, 84602, United States
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14
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Puentes AR, Morejón MC, Rivera DG, Wessjohann LA. Peptide Macrocyclization Assisted by Traceless Turn Inducers Derived from Ugi Peptide Ligation with Cleavable and Resin-Linked Amines. Org Lett 2017; 19:4022-4025. [PMID: 28704057 DOI: 10.1021/acs.orglett.7b01761] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A multicomponent approach enabling the installation of turn-inducing moieties that facilitate the macrocyclization of short and medium-size oligopeptides is described. The strategy comprises the Ugi ligation of peptide carboxylic acids and isocyanopeptides in the presence of aldehydes and acid or photolabile amines followed by cyclization and cleavage of the backbone N-substituents to render canonical cyclopeptides. Implementing the approach on solid phase with the use of Rink amide resins led to a new class of backbone amide linker strategy.
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Affiliation(s)
- Alfredo R Puentes
- Department of Bioorganic Chemistry, Leibniz Institute of Plant Biochemistry , Weinberg 3, 06120 Halle/Saale, Germany.,Center for Natural Products Research, Faculty of Chemistry, University of Havana , Zapata y G, 10400 Havana, Cuba
| | - Micjel C Morejón
- Department of Bioorganic Chemistry, Leibniz Institute of Plant Biochemistry , Weinberg 3, 06120 Halle/Saale, Germany.,Center for Natural Products Research, Faculty of Chemistry, University of Havana , Zapata y G, 10400 Havana, Cuba
| | - Daniel G Rivera
- Department of Bioorganic Chemistry, Leibniz Institute of Plant Biochemistry , Weinberg 3, 06120 Halle/Saale, Germany.,Center for Natural Products Research, Faculty of Chemistry, University of Havana , Zapata y G, 10400 Havana, Cuba
| | - Ludger A Wessjohann
- Department of Bioorganic Chemistry, Leibniz Institute of Plant Biochemistry , Weinberg 3, 06120 Halle/Saale, Germany
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