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Allouche EMD, Grinhagena E, Waser J. Hypervalent Iodine-Mediated Late-Stage Peptide and Protein Functionalization. Angew Chem Int Ed Engl 2021; 61:e202112287. [PMID: 34674359 PMCID: PMC9299824 DOI: 10.1002/anie.202112287] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Indexed: 12/20/2022]
Abstract
Hypervalent iodine compounds are powerful reagents for the development of novel transformations. As they exhibit low toxicity, high functional group tolerance, and stability in biocompatible media, they have been used for the functionalization of biomolecules. Herein, we report recent advances up to June 2021 in peptide and protein modification using hypervalent iodine reagents. Their use as group transfer or oxidizing reagents is discussed in this Minireview, including methods targeting polar, aromatic, or aliphatic amino acids and peptide termini.
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Zhang K, Rombach D, Nötel NY, Jeschke G, Katayev D. Radical Trifluoroacetylation of Alkenes Triggered by a Visible-Light-Promoted C-O Bond Fragmentation of Trifluoroacetic Anhydride. Angew Chem Int Ed Engl 2021; 60:22487-22495. [PMID: 34289531 PMCID: PMC8518413 DOI: 10.1002/anie.202109235] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Indexed: 01/30/2023]
Abstract
We report a mild and operationally simple trifluoroacylation strategy of olefines, that utilizes trifluoroacetic anhydride as a low‐cost and readily available reagent. This light‐mediated process is fundamentally different from conventional methodologies and occurs through a trifluoroacyl radical mechanism promoted by a photocatalyst, which triggers a C−O bond fragmentation. Mechanistic studies (kinetic isotope effects, spectroelectrochemistry, optical spectroscopy, theoretical investigations) highlight the evidence of a fleeting CF3CO radical under photoredox conditions. The trifluoroacyl radical can be stabilized under CO atmosphere, delivering the trifluoroacetylation product with higher chemical efficiency. Furthermore, the method can be turned into a trifluoromethylation protocol by simply changing the reaction parameters. Beyond simple alkenes, this method allows for chemo‐ and regioselective functionalization of small‐molecule drugs and common pharmacophores.
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Son J. Sustainable manganese catalysis for late-stage C-H functionalization of bioactive structural motifs. Beilstein J Org Chem 2021; 17:1733-1751. [PMID: 34386100 PMCID: PMC8329386 DOI: 10.3762/bjoc.17.122] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 07/15/2021] [Indexed: 01/31/2023] Open
Abstract
The late-stage C–H functionalization of bioactive structural motifs is a powerful synthetic strategy for accessing advanced agrochemicals, bioimaging materials, and drug candidates, among other complex molecules. While traditional late-stage diversification relies on the use of precious transition metals, the utilization of 3d transition metals is an emerging approach in organic synthesis. Among the 3d metals, manganese catalysts have gained increasing attention for late-stage diversification due to the sustainability, cost-effectiveness, ease of operation, and reduced toxicity. Herein, we summarize recent manganese-catalyzed late-stage C–H functionalization reactions of biologically active small molecules and complex peptides.
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Bay AV, Fitzpatrick KP, González-Montiel GA, Farah AO, Cheong PHY, Scheidt KA. Light-Driven Carbene Catalysis for the Synthesis of Aliphatic and α-Amino Ketones. Angew Chem Int Ed Engl 2021; 60:17925-17931. [PMID: 34097802 PMCID: PMC8338790 DOI: 10.1002/anie.202105354] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/24/2021] [Indexed: 01/02/2023]
Abstract
Single-electron N-heterocyclic carbene (NHC) catalysis has gained attention recently for the synthesis of C-C bonds. Guided by density functional theory and mechanistic analyses, we report the light-driven synthesis of aliphatic and α-amino ketones using single-electron NHC operators. Computational and experimental results reveal that the reactivity of the key radical intermediate is substrate-dependent and can be modulated through steric and electronic parameters of the NHC. Catalyst potential is harnessed in the visible-light driven generation of an acyl azolium radical species that undergoes selective coupling with various radical partners to afford diverse ketone products. This methodology is showcased in the direct late-stage functionalization of amino acids and pharmaceutical compounds, highlighting the utility of single-electron NHC operators.
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Besson T, Fruit C. Recent Advances in Transition-Metal-Free Late-Stage C-H and N-H Arylation of Heteroarenes Using Diaryliodonium Salts. Pharmaceuticals (Basel) 2021; 14:661. [PMID: 34358087 PMCID: PMC8308686 DOI: 10.3390/ph14070661] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 07/07/2021] [Accepted: 07/09/2021] [Indexed: 12/21/2022] Open
Abstract
Transition-metal-free direct arylation of C-H or N-H bonds is one of the key emerging methodologies that is currently attracting tremendous attention. Diaryliodonium salts serve as a stepping stone on the way to alternative environmentally friendly and straightforward pathways for the construction of C-C and C-heteroatom bonds. In this review, we emphasize the recent synthetic advances of late-stage C(sp2)-N and C(sp2)-C(sp2) bond-forming reactions under metal-free conditions using diaryliodonium salts as arylating reagent and its applications to the synthesis of new arylated bioactive heterocyclic compounds.
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Alvarez EM, Karl T, Berger F, Torkowski L, Ritter T. Late-Stage Heteroarylation of Hetero(aryl)sulfonium Salts Activated by α-Amino Alkyl Radicals. Angew Chem Int Ed Engl 2021; 60:13609-13613. [PMID: 33835680 PMCID: PMC8251951 DOI: 10.1002/anie.202103085] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Indexed: 11/25/2022]
Abstract
We report a late‐stage heteroarylation of aryl sulfonium salts through activation with α‐amino alkyl radicals in a mechanistically distinct approach from previously reported halogen‐atom transfer (XAT). The new mode of activation of aryl sulfonium salts proceeds in the absence of light and photoredox catalysts, engaging a wide range of hetarenes. Furthermore, we demonstrate the applicability of this methodology in synthetically useful cross‐coupling transformations.
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Czerwiński PJ, Furman B. Reductive Functionalization of Amides in Synthesis and for Modification of Bioactive Compounds. Front Chem 2021; 9:655849. [PMID: 33981672 PMCID: PMC8107389 DOI: 10.3389/fchem.2021.655849] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 02/23/2021] [Indexed: 11/13/2022] Open
Abstract
In this review, applications of the amide reductive functionalization methodology for the synthesis and modification of bioactive compounds are covered. A brief summary of the different protocols is presented in the introduction, followed by the synthetic application of these in late-stage functionalization, leading to known pharmaceuticals or to their derivatives, including bioisosteres, with potential higher activity as the main axis of the article. The synthetic approach to natural products based on amide reduction is also discussed; however, this is given in a condensed form focusing on recent or as yet unexplored applications due to a number of recently published excellent reviews covering this topic. The aim of this review is to illustrate the potential of reductive functionalization of amides as an elegant and useful tool in the synthesis of bioactive compounds and inspire further work in this field.
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Sun X, Ritter T. Decarboxylative Polyfluoroarylation of Alkylcarboxylic Acids. Angew Chem Int Ed Engl 2021; 60:10557-10562. [PMID: 33481305 PMCID: PMC8252513 DOI: 10.1002/anie.202015596] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Indexed: 12/17/2022]
Abstract
Polyfluoroarenes are useful building blocks in several areas such as drug discovery, materials, and crop protection. Herein, we report the first polyfluoroarylation of aliphatic carboxylic acids via photoredox decarboxylation. The method proceeds with broad substrate scope and high functional group tolerance. Moreover, small complex molecules such as natural products and drugs can be modified by late-stage modification.
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Johnson DJG, Jenkins ID, Huxley C, Coster MJ, Lum KY, White JM, Avery VM, Davis RA. Synthesis of New Triazolopyrazine Antimalarial Compounds. Molecules 2021; 26:molecules26092421. [PMID: 33919319 PMCID: PMC8122397 DOI: 10.3390/molecules26092421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/15/2021] [Accepted: 04/15/2021] [Indexed: 11/29/2022] Open
Abstract
A radical approach to late-stage functionalization using photoredox and Diversinate™ chemistry on the Open Source Malaria (OSM) triazolopyrazine scaffold (Series 4) resulted in the synthesis of 12 new analogues, which were characterized by NMR, UV, and MS data analysis. The structures of four triazolopyrazines were confirmed by X-ray crystal structure analysis. Several minor and unexpected side products were generated during these studies, including two resulting from a possible disproportionation reaction. All compounds were tested for their ability to inhibit the growth of the malaria parasite Plasmodium falciparum (3D7 and Dd2 strains) and for cytotoxicity against a human embryonic kidney (HEK293) cell line. Moderate antimalarial activity was observed for some of the compounds, with IC50 values ranging from 0.3 to >20 µM; none of the compounds displayed any toxicity against HEK293 at 80 µM.
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Larraufie MH, Gao X, Xia X, Devine PJ, Kallen J, Liu D, Michaud G, Harsch A, Savage N, Ding J, Tan K, Mihalic M, Roggo S, Canham SM, Bushell SM, Krastel P, Gao J, Izaac A, Altinoglu E, Lustenberger P, Salcius M, Harbinski F, Williams ET, Zeng L, Loureiro J, Cong F, Fryer CJ, Klickstein L, Tallarico JA, Jain RK, Rothman DM, Wang S. Phenotypic screen identifies calcineurin-sparing FK506 analogs as BMP potentiators for treatment of acute kidney injury. Cell Chem Biol 2021; 28:1271-1282.e12. [PMID: 33894161 DOI: 10.1016/j.chembiol.2021.04.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 01/29/2021] [Accepted: 04/05/2021] [Indexed: 12/12/2022]
Abstract
Acute kidney injury (AKI) is a life-threatening disease with no known curative or preventive therapies. Data from multiple animal models and human studies have linked dysregulation of bone morphogenetic protein (BMP) signaling to AKI. Small molecules that potentiate endogenous BMP signaling should have a beneficial effect in AKI. We performed a high-throughput phenotypic screen and identified a series of FK506 analogs that act as potent BMP potentiators by sequestering FKBP12 from BMP type I receptors. We further showed that calcineurin inhibition was not required for this activity. We identified a calcineurin-sparing FK506 analog oxtFK through late-stage functionalization and structure-guided design. OxtFK demonstrated an improved safety profile in vivo relative to FK506. OxtFK stimulated BMP signaling in vitro and in vivo and protected the kidneys in an AKI mouse model, making it a promising candidate for future development as a first-in-class therapeutic for diseases with dysregulated BMP signaling.
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Ceballos J, Grinhagena E, Sangouard G, Heinis C, Waser J. Cys-Cys and Cys-Lys Stapling of Unprotected Peptides Enabled by Hypervalent Iodine Reagents. Angew Chem Int Ed Engl 2021; 60:9022-9031. [PMID: 33450121 PMCID: PMC8048981 DOI: 10.1002/anie.202014511] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/22/2020] [Indexed: 12/31/2022]
Abstract
Easy access to a wide range of structurally diverse stapled peptides is crucial for the development of inhibitors of protein-protein interactions. Herein, we report bis-functional hypervalent iodine reagents for two-component cysteine-cysteine and cysteine-lysine stapling yielding structurally diverse thioalkyne linkers. This stapling method works with unprotected natural amino acid residues and does not require pre-functionalization or metal catalysis. The products are stable to purification and isolation. Post-stapling modification can be accessed via amidation of an activated ester, or via cycloaddition onto the formed thioalkyne group. Increased helicity and binding affinity to MDM2 was obtained for a i,i+7 stapled peptide.
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37
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David F, Davis AM, Gossing M, Hayes MA, Romero E, Scott LH, Wigglesworth MJ. A Perspective on Synthetic Biology in Drug Discovery and Development-Current Impact and Future Opportunities. SLAS DISCOVERY 2021; 26:581-603. [PMID: 33834873 DOI: 10.1177/24725552211000669] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The global impact of synthetic biology has been accelerating, because of the plummeting cost of DNA synthesis, advances in genetic engineering, growing understanding of genome organization, and explosion in data science. However, much of the discipline's application in the pharmaceutical industry remains enigmatic. In this review, we highlight recent examples of the impact of synthetic biology on target validation, assay development, hit finding, lead optimization, and chemical synthesis, through to the development of cellular therapeutics. We also highlight the availability of tools and technologies driving the discipline. Synthetic biology is certainly impacting all stages of drug discovery and development, and the recognition of the discipline's contribution can further enhance the opportunities for the drug discovery and development value chain.
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38
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Fawcett A, Keller MJ, Herrera Z, Hartwig JF. Site Selective Chlorination of C(sp 3 )-H Bonds Suitable for Late-Stage Functionalization. Angew Chem Int Ed Engl 2021; 60:8276-8283. [PMID: 33480134 DOI: 10.1002/anie.202016548] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 01/03/2021] [Indexed: 01/18/2023]
Abstract
C(sp3 )-Cl bonds are present in numerous biologically active small molecules, and an ideal route for their preparation is by the chlorination of a C(sp3 )-H bond. However, most current methods for the chlorination of C(sp3 )-H bonds are insufficiently site selective and tolerant of functional groups to be applicable to the late-stage functionalization of complex molecules. We report a method for the highly selective chlorination of tertiary and benzylic C(sp3 )-H bonds to produce the corresponding chlorides, generally in high yields. The reaction occurs with a mixture of an azidoiodinane, which generates a selective H-atom abstractor under mild conditions, and a readily-accessible and inexpensive copper(II) chloride complex, which efficiently transfers a chlorine atom. The reaction's exceptional functional group tolerance is demonstrated by the chlorination of >30 diversely functionalized substrates and the late-stage chlorination of a dozen derivatives of natural products and active pharmaceutical ingredients.
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McMillan AJ, Sieńkowska M, Di Lorenzo P, Gransbury GK, Chilton NF, Salamone M, Ruffoni A, Bietti M, Leonori D. Practical and Selective sp 3 C-H Bond Chlorination via Aminium Radicals. Angew Chem Int Ed Engl 2021; 60:7132-7139. [PMID: 33458924 PMCID: PMC8048631 DOI: 10.1002/anie.202100030] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Indexed: 12/12/2022]
Abstract
The introduction of chlorine atoms into organic molecules is fundamental to the manufacture of industrial chemicals, the elaboration of advanced synthetic intermediates and also the fine-tuning of physicochemical and biological properties of drugs, agrochemicals and polymers. We report here a general and practical photochemical strategy enabling the site-selective chlorination of sp3 C-H bonds. This process exploits the ability of protonated N-chloroamines to serve as aminium radical precursors and also radical chlorinating agents. Upon photochemical initiation, an efficient radical-chain propagation is established allowing the functionalization of a broad range of substrates due to the large number of compatible functionalities. The ability to synergistically maximize both polar and steric effects in the H-atom transfer transition state through appropriate selection of the aminium radical has provided the highest known selectivity in radical sp3 C-H chlorination.
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Non-regioselective functionalization: an underestimate chemical diversity generator in medicinal chemistry. Future Med Chem 2021; 13:595-599. [PMID: 33657835 DOI: 10.4155/fmc-2021-0011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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41
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Zhao R, Fu K, Fang Y, Zhou J, Shi L. Site-Specific C(sp 3 )-H Aminations of Imidates and Amidines Enabled by Covalently Tethered Distonic Radical Anions. Angew Chem Int Ed Engl 2020; 59:20682-20690. [PMID: 32706927 DOI: 10.1002/anie.202008806] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/21/2020] [Indexed: 11/11/2022]
Abstract
The utilization of N-centered radicals to synthesize nitrogen-containing compounds has attracted considerable attention recently, due to their powerful reactivities and the concomitant construction of C-N bonds. However, the generation and control of N-centered radicals remain particularly challenging. We report a tethering strategy using SOMO-HOMO-converted distonic radical anions for the site-specific aminations of imidates and amidines with aid of the non-covalent interaction. This reaction features a remarkably broad substrate scope and also enables the late-stage functionalization of bioactive molecules. Furthermore, the reaction mechanism is thoroughly investigated through kinetic studies, Raman spectroscopy, electron paramagnetic resonance spectroscopy, and density functional theory calculations, revealing that the aminations likely involve direct homolytic cleavage of N-H bonds and subsequently controllable 1,5 or 1,6 hydrogen atom transfer.
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Abstract
Tryprostatin A and B are prenylated, tryptophan-containing, diketopiperazine natural products, displaying cytotoxic activity through different mechanisms of action. The presence of the 6-methoxy substituent on the indole moiety of tryprostatin A was shown to be essential for the dual inhibition of topoisomerase II and tubulin polymerization. However, the inability to perform late-stage modification of the indole ring has limited the structure–activity relationship studies of this class of natural products. Herein, we describe an efficient chemoenzymatic approach for the late-stage modification of tryprostatin B using a cyclic dipeptide N-prenyltransferase (CdpNPT) from Aspergillus fumigatus, which generates novel analogs functionalized with allylic, benzylic, heterocyclic, and diene moieties. Notably, this biocatalytic functionalizational study revealed high selectivity for the indole C6 position. Seven of the 11 structurally characterized analogs were exclusively C6-alkylated, and the remaining four contained predominant C6-regioisomers. Of the 24 accepted substrates, 10 provided >50% conversion and eight provided 20–50% conversion, with the remaining six giving <20% conversion under standard conditions. This study demonstrates that prenyltransferase-based late-stage diversification enables direct access to previously inaccessible natural product analogs.
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Kallepu S, Neeli PK, Mallappa S, Nagendla NK, Reddy Mudiam MK, Mainkar PS, Kotamraju S, Chandrasekhar S. sp 3 -Rich Glycyrrhetinic Acid Analogues Using Late-Stage Functionalization as Potential Breast Tumor Regressing Agents. ChemMedChem 2020; 15:1826-1833. [PMID: 32893968 DOI: 10.1002/cmdc.202000400] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Indexed: 12/28/2022]
Abstract
Late-stage functionalization (LSF) aids drug discovery efforts by introducing functional groups onto C-H bonds on pre-existing skeletons. We adopted the LSF strategy to synthesize analogues of the abundantly available triterpenoid, glycyrrhetinic acid (GA), by introducing aryl groups in the A-ring, expanding the A-ring and selectively activating one methyl group of the gem-dimethyl groups. Intriguingly, two compounds were found to preferentially accumulate in the mitochondrial compartment of MDA-MB-231 breast cancer cells, to cause depolarization of mitochondrial membrane potential and to induce antiproliferative and anti-invasive effects through enhanced mitochondrial superoxide production with parallel depletion of GSH levels. Furthermore, intraperitoneal administration of these two compounds, in comparison with GA, greatly regressed breast tumor growth and metastasis in a SCID mouse model bearing labeled MDA-MB-231 cells.
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Robinson H, Oatley SA, Rowedder JE, Slade P, Macdonald SJF, Argent SP, Hirst JD, McInally T, Moody CJ. Late-Stage Functionalization by Chan-Lam Amination: Rapid Access to Potent and Selective Integrin Inhibitors. Chemistry 2020; 26:7678-7684. [PMID: 32129907 DOI: 10.1002/chem.202001059] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Indexed: 11/07/2022]
Abstract
A late-stage functionalization of the aromatic ring in amino acid derivatives is described. The key step is a copper-catalysed diversification of a boronate ester by amination (Chan-Lam reaction) that can be carried out on a complex β-aryl-β-amino acid scaffold. This not only considerably extends the substrate scope of amination partners, but also delivers an array of potent and selective integrin inhibitors as potential treatment agents of idiopathic pulmonary fibrosis (IPF). This versatile chemical strategy, which is amenable to high-throughput-array protocols, allows the installation of pharmaceutically valuable heteroaromatic fragments at a late stage by direct coupling to NH heterocycles, leading to compounds with drug-like attributes. It thus constitutes a useful addition to the medicinal chemist's repertoire.
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Abstract
A formal C-H carboxylation of unactivated arenes using CO2 in green solvents is described. The present strategy combines a sterically controlled Ir-catalyzed C-H borylation followed by a Cu-catalyzed carboxylation of the in situ generated organoboronates. The reaction is highly regioselective for the C-H carboxylation of 1,3-disubstituted and 1,2,3-trisubstituted benzenes, 1,2- or 1,4-symmetrically substituted benzenes, fluorinated benzenes and different heterocycles. The developed methodology was applied to the late-stage C-H carboxylation of commercial drugs and ligands.
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Di Nardo G, Gilardi G. Natural Compounds as Pharmaceuticals: The Key Role of Cytochromes P450 Reactivity. Trends Biochem Sci 2020; 45:511-525. [PMID: 32413326 DOI: 10.1016/j.tibs.2020.03.004] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 02/28/2020] [Accepted: 03/06/2020] [Indexed: 12/16/2022]
Abstract
The design of drugs from natural products is a re-emerging area due to the need for bioactive compounds. The exploitation of natural products and their derivatives obtained by biocatalysis is in line with the higher attention given today to new sustainable technologies that better preserve the environment (green chemistry). The research field of cytochromes P450 (CYPs) is continuously providing new enzymes and mutants that produce metabolites suitable for late-stage functionalization for new potential drugs. This review provides an overview of the exploitation of CYPs as biocatalysts in drug synthesis. Additionally, recent progress in protein and metabolic engineering is provided to show how these enzymes offer a toolbox that can be combined with other biocatalytic or chemical processes to build new platforms for the green production of new drugs.
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Xu P, Zhao D, Berger F, Hamad A, Rickmeier J, Petzold R, Kondratiuk M, Bohdan K, Ritter T. Site-Selective Late-Stage Aromatic [ 18 F]Fluorination via Aryl Sulfonium Salts. Angew Chem Int Ed Engl 2020; 59:1956-1960. [PMID: 31697427 PMCID: PMC7004179 DOI: 10.1002/anie.201912567] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Indexed: 01/20/2023]
Abstract
Site-selective functionalization of C-H bonds in small complex molecules is a long-standing challenge in organic chemistry. Herein, we report a broadly applicable and site-selective aromatic C-H dibenzothiophenylation reaction. The conceptual advantage of this transformation is further demonstrated through the two-step C-H [18 F]fluorination of a series of marketed small-molecule drugs.
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Tan C, Liu X, Jia H, Zhao X, Chen J, Wang Z, Tan J. Practical Synthesis of Phosphinic Amides/Phosphoramidates through Catalytic Oxidative Coupling of Amines and P(O)-H Compounds. Chemistry 2019; 26:881-887. [PMID: 31625634 DOI: 10.1002/chem.201904237] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 10/17/2019] [Indexed: 12/24/2022]
Abstract
Herein, we report a highly efficient ZnI2 -triggered oxidative cross-coupling reaction of P(O)-H compounds and amines. This operationally simple protocol provides unprecedented generic access to phosphinic amides/phosphoramidate derivatives in good yields and short reaction time. Besides, the reaction proceeds under mild conditions, which avoids the use of hazardous reagents, and is applicable to scale-up syntheses as well as late-stage functionalization of drug molecules. The stereospecific coupling is also achieved from readily available optically enriched P(O)-H compounds.
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Egbewande FA, Coster MJ, Jenkins ID, Davis RA. Reaction of Papaverine with Baran Diversinates TM. Molecules 2019; 24:molecules24213938. [PMID: 31683610 PMCID: PMC6864744 DOI: 10.3390/molecules24213938] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/24/2019] [Accepted: 10/28/2019] [Indexed: 12/01/2022] Open
Abstract
The reaction of papaverine with a series of Baran DiversinatesTM is reported. Although the yields were low, it was possible to synthesize a small biodiscovery library using this plant alkaloid as a scaffold for late-stage C–H functionalization. Ten papaverine analogues (2–11), including seven new compounds, were synthesized. An unexpected radical-induced exchange reaction is reported where the dimethoxybenzyl group of papaverine was replaced by an alkyl group. This side reaction enabled the synthesis of additional novel fragments based on the isoquinoline scaffold, which is present in numerous natural products. Possible reasons for the poor yields in the DiversinateTM reactions with this particular scaffold are discussed.
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50
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Wang Q, Qu Y, Tian H, Liu Y, Song H, Wang Q. Trifluoromethylation and Monofluoroalkenylation of Alkenes through Radical-Radical Cross-Coupling. Chemistry 2019; 25:8686-8690. [PMID: 31025767 DOI: 10.1002/chem.201901349] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 04/26/2019] [Indexed: 11/07/2022]
Abstract
The first visible-light-induced trifluoromethylation and monofluoroalkenylation of simple alkenes via a challenging radical-radical cross-coupling step was achieved. This method provided a mild, step-economical and redox-neutral route to privileged two different fluorinated difunctionalized allyl compounds. The utility of this method is illustrated by late-stage modification of medically important molecules.
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