ORCID Profile
0000-0001-6286-9105
Current Organisation
The University of Auckland
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Publisher: American Chemical Society (ACS)
Date: 29-06-2020
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7OB02169K
Abstract: Six analogues of the potent lipopeptide antibiotic, teixobactin were prepared by Fmoc SPPS and their activities examined against Gram positive bacteria.
Publisher: American Chemical Society (ACS)
Date: 28-01-2020
DOI: 10.1021/ACS.ORGLETT.9B04567
Abstract: 2-Bromo-1,3-butadienes are demonstrated to be effective substrates for tandem Diels-Alder/transition metal cross-coupling reaction sequences. Intermolecular cycloaddition of a 2-bromo-1,3-diene with activated dienophiles proceeded under Lewis acid catalysis in generally high yields with good to excellent
Publisher: Wiley
Date: 28-03-2023
Abstract: Azide‐enolate cycloaddition‐rearrangements offer potential for rapid access to erse molecular frameworks from simple precursors. We report here that investigations into the cycloadditions of ester or amide enolates with vinyl azides led to the identification of two reaction processes – direct α‐amination of amides and lactams, and the synthesis of ene‐γ‐lactams from esters. The outcomes of these reactions depended on the fate of key vinyl triazoline intermediates generated in the initial cycloaddition step. Isolation of reaction intermediates in the ene‐γ‐lactam synthesis revealed the unexpected addition of two enolate equivalents, one of which is later eliminated. Computational studies further suggested an unusual reaction pathway involving direct addition of an enolate to the terminal carbon of the N‐ vinyl triazoline. In contrast, the α‐amination of amides and lactams proceeded by rearrangement of the intermediate triazoline to give an imine, hydrolysis or reduction of which gave access to primary or secondary α‐amino amides or lactams.
Publisher: Georg Thieme Verlag KG
Date: 19-02-2020
Abstract: Asymmetric access to α-hydroxy-1,4-diketones has been achieved by direct ene coupling of silyl enol ethers with glyoxal electrophiles, mediated by a chiral N,N′-dioxide–nickel(II) complex catalyst. Successful union of a polyketide silyl enol ether with an α-quaternary glyoxal, generated by dioxirane oxidation of an α-diazo ketone, models a proposed C5–C6 disconnection of the polyketide and spirocyclic imine domains of the marine natural product, portimine.
Publisher: Royal Society of Chemistry (RSC)
Date: 2023
DOI: 10.1039/D2OB01992B
Abstract: This work details a novel approach to access the [7,6]-spirocyclic fragment of 13-desmethyl spirolide C. A more efficient synthesis of the key lactam dienophile is reported, and a comprehensive investigation of the Diels-Alder reaction is included.
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C8NP00051D
Abstract: 2-Formylpyrroles constitute a large and growing family of bioactive Maillard reaction products found in food, traditional medicine and throughout nature.
Publisher: American Chemical Society (ACS)
Date: 17-04-2023
Publisher: Wiley
Date: 11-05-2023
Publisher: Wiley
Date: 23-05-2017
Publisher: American Chemical Society (ACS)
Date: 12-09-2017
DOI: 10.1021/ACS.ORGLETT.7B02687
Abstract: The total synthesis of the 2-nitropyrrole natural products nitropyrrolins A and B and the formal synthesis of nitropyrrolin D are reported. The key 2-nitro-4-alkylpyrrole core was efficiently assembled by Sonogashira cross-coupling, with complete control of regioselectivity. An unusual carboxylative cyclization, sulfonylcarbamate formation, and base-promoted cleavage sequence enabled access to the key hydroxy ketone without affecting the protected 2-nitropyrrole unit. The total synthesis provides a general approach for preparation of the bioactive nitropyrrolin family of natural products.
Publisher: Wiley
Date: 11-05-2023
Abstract: Invited for the cover of this issue are Dan Furkert, Joe Bell‐Tyrer and co‐workers at the University of Auckland and Victoria University of Wellington. The image depicts a tandem cycloaddition–rearrangement process delivering a erse range of molecular frameworks from simple precursors. Read the full text of the article at 10.1002/chem.202300261 .
Publisher: American Chemical Society (ACS)
Date: 10-10-2017
Abstract: The stereoselective access to stereotriads as important polyketide building blocks is reported on the basis of the Krische-type hydrogen-mediated syn-crotylation. The products were obtained with an extremely high diastereoselectivity (dr >99:1), and the newly formed syn stereocenters were controlled solely by the chiral catalyst. The stereochemistry was assigned by crystallography and HPLC for both product manifolds. This extension of the burgeoning transfer hydrogen methodology gives ergent asymmetric access to anti,syn and syn,syn polyketide stereotriads from the same α-chiral starting material and avoids potentially epimerizable aldehyde intermediates.
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C9OB00262F
Abstract: In situ generation and reaction of novel 5-membered N -tosyl cyclic α,β-unsaturated iminium ions from readily prepared stable precursors is demonstrated.
Publisher: Wiley
Date: 10-07-2019
Abstract: Syn dihydroxyketone motifs are embedded in a wide range of biologically active natural products, however the development of stereoselective synthetic methods to assemble these structures has proven a challenging task. We report a highly diastereoselective method for the synthesis of syn dihydroxyketones from propargylic alcohols, with wide scope for application in natural product synthesis. The reaction sequence involves regioselective cyclisation of propargylic alcohols with incorporation of a triketone to give enol dioxolanes that are then diastereoselectively epoxidised to form unusual spiroepoxide intermediates. Hydrolysis affords syn dihydroxyketones as essentially single diastereisomers. The reaction sequence is operationally simple, of wide substrate scope, and remarkably can be efficiently carried out as a one‐pot process with no loss of overall yield or diastereoselectivity.
Publisher: American Chemical Society (ACS)
Date: 10-2018
Abstract: Fundamental study of the reactivity of 2-nitropyrrole systems has enabled the identification of effective methods for incorporation of this unusual motif into advanced natural product frameworks. The presence of electron-rich pyrrole N-protecting groups (BOM, Boz) was demonstrated to enable a variety of previously unsuccessful palladium-mediated cross-couplings to be carried out in high yield. Based on this foundation, a series of regio- and stereoselective synthetic routes toward the nitropyrrolin and heronapyrrole families of natural products was developed by our group (G1-3). A full account of the strategic evolution of these approaches is reported here, highlighting the details of the setbacks encountered and eventual successes achieved en route, including the total synthesis of heronapyrrole B. The fundamental studies and completed total syntheses provide general access to the bioactive 2-nitropyrrole natural product manifold and also establish practical and efficient methods for preparation and elaboration of the medicinally relevant 2-nitropyrrole motif.
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C9QO00769E
Abstract: Intramolecular Diels–Alder [4 + 2] cycloaddition using a chiral Evans oxazolidinone auxiliary affords the trans -decalin framework of the potent antibiotic anthracimycin.
Publisher: Wiley
Date: 22-08-2018
Abstract: The Diels-Alder cycloaddition reaction has become established as a fundamental approach for the preparation of complex natural products however, successful application of the intermolecular Diels-Alder cycloaddition reaction to the synthesis of particularly congested scaffolds remains surprisingly problematic. Inspired by the terpenoid spiroketal natural product leonuketal, a challenging telescoped reaction sequence has been realized to access the core [2.2.2]-bicyclic lactone ring system and its [3.2.1] isomer. Our four-step, protecting-group-free process required detailed investigation to circumvent the problems of adduct fragmentation and intermediate instability. Successful solution of these practical issues, along with unambiguous structural determination of the target structures, provide useful insights that will facilitate future applications of the Diels-Alder cycloaddition reaction to challenging, highly congested molecular scaffolds and ongoing synthetic efforts towards this natural product.
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7OB00496F
Abstract: This review summarises the application of gold catalysis for the syntheses of spiro, bridged and fused ketal natural products.
Publisher: American Chemical Society (ACS)
Date: 18-07-2019
DOI: 10.1021/ACS.JNATPROD.9B00351
Abstract: Natural products containing a lumazine motif were first isolated from natural sources in 1940. These natural products are relatively rare, with fewer than 100 lumazines known to occur in Nature. This review discusses the isolation of lumazines, their biological activity, and their biosynthesis, where known.
Publisher: American Chemical Society (ACS)
Date: 07-06-2017
DOI: 10.1021/ACS.JNATPROD.7B00314
Abstract: The first total synthesis of the 2-formylpyrrole alkaloid hemerocallisamine I is reported. The convergent synthesis features a key Maillard-type condensation of a complex amine derived from cis-4-hydroxy-l-proline with a dihydropyranone, to directly furnish the 2-formylpyrrole ring system. The absolute configuration of hemerocallisamine I has been revised on the basis of optical rotation data obtained for the synthesized compound.
Publisher: Wiley
Date: 07-09-2020
Publisher: American Chemical Society (ACS)
Date: 26-02-2018
Abstract: The asymmetric total synthesis of the polyketide benzannulated spiroketal natural product, (-)-peniphenone A, is reported. The key reaction in the synthesis involved sp
Publisher: American Chemical Society (ACS)
Date: 08-04-2020
Publisher: American Chemical Society (ACS)
Date: 16-01-2018
DOI: 10.1021/ACS.ORGLETT.7B03925
Abstract: The first total synthesis of the highly N-methylated acetylene-containing lipopeptide jahanyne, an apoptosis-inducing natural product from marine cyanobacteria, is reported. A late-stage solution-phase coupling enabled introduction of the C-terminal ketone pyrrolidine moiety. A modified Fmoc solid-phase synthesis strategy was adopted to effectively couple multiple sterically hindered N-methylated amino acids while suppressing epimerization. The total synthesis has enabled confirmation of the proposed absolute configuration of natural jahanyne.
Publisher: American Chemical Society (ACS)
Date: 21-10-2020
Publisher: Royal Society of Chemistry (RSC)
Date: 2023
DOI: 10.1039/D3OB00998J
Abstract: Synthesis of the spirocyclic core of portimines A and B was achieved utilizing a key Diels–Alder reaction of a bromodiene with a malonate dienophile.
Publisher: Georg Thieme Verlag KG
Date: 13-02-2020
Abstract: Cyclic imine marine toxins have attracted considerable attention from the synthetic community in the past two decades due to their unique chemical structures and clinically relevant biological activities. This review presents recent efforts of our group in the development of various strategies to efficiently construct the common spirocyclic imine fragments of the cyclic imine toxins. In particular, the use of α,β-unsaturated N-acyl iminium ion dienophiles in Diels–Alder reactions are highlighted, whereby direct access to spirocyclic imine motifs was obtained and important mechanistic details were discovered. Alternative approaches to spirocyclic imine systems involving hydroamination of amino alkynes are also summarized. One such approach led to serendipitous access to N-vinyl amide products, while our most recently reported approach involving an intermolecular Diels–Alder/cross-coupling sequence using novel 2-bromo-1,3-butadienes to access 5,6-spirocyclic imines is also discussed. Additionally, the development of a novel method to construct another challenging motif present in the portimines is also introduced. 1 Introduction 2 Strategies towards the Spirocyclic Imine Fragment of Cyclic Imine Toxins 2.1 Diels–Alder Cycloadditions of α,β-Unsaturated N-Acyl Iminium Dienophiles 2.2 Early Studies Using in situ-Generated Iminium Ion Dienophiles 2.3 Use of More Stable Iminium Ion Dienophiles for Diels–Alder Reactions 2.4 Other Notable Strategies towards Spirocyclic Imines 2.5 Recent Efforts towards the 5,6-Spirocyclic Imine Marine Toxin Portimine A 2.6 Construction of Another Challenging Motif of Portimine A 3 Conclusion and Future Perspectives
Publisher: Elsevier BV
Date: 06-2020
Publisher: Wiley
Date: 10-07-2019
Abstract: Syn dihydroxyketone motifs are embedded in a wide range of biologically active natural products, however the development of stereoselective synthetic methods to assemble these structures has proven a challenging task. We report a highly diastereoselective method for the synthesis of syn dihydroxyketones from propargylic alcohols, with wide scope for application in natural product synthesis. The reaction sequence involves regioselective cyclisation of propargylic alcohols with incorporation of a triketone to give enol dioxolanes that are then diastereoselectively epoxidised to form unusual spiroepoxide intermediates. Hydrolysis affords syn dihydroxyketones as essentially single diastereisomers. The reaction sequence is operationally simple, of wide substrate scope, and remarkably can be efficiently carried out as a one‐pot process with no loss of overall yield or diastereoselectivity.
Publisher: Royal Society of Chemistry (RSC)
Date: 2023
DOI: 10.1039/D3CB00075C
Abstract: Viral infections are one of the leading causes of acute morbidity in humans and much endeavour has been made by the synthetic community for the development of drugs to treat associated diseases.
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C6CC07532K
Abstract: The heronapyrroles are a family of antibiotic natural products containing the rare 2-nitropyrrole motif.
Publisher: Wiley
Date: 23-05-2017
Abstract: The unexpected synthesis of industrially important N-vinyl amides directly from aldehydes and α,β-unsaturated N-vinyl amides from esters is reported. This reaction probably proceeds through an initial [3+2] azide-enolate cycloaddition involving a vinyl azide generated in situ. A survey of the reaction scope and preliminary mechanistic findings supported by quantum computational analysis are reported, with implications for the future development of atom-efficient amide synthesis. Intriguingly, this study suggests that (cautious) reevaluation of azidoethene as a synthetic reagent may be warranted.
Publisher: American Chemical Society (ACS)
Date: 09-2021
Location: United Kingdom of Great Britain and Northern Ireland
Start Date: 2015
End Date: 2018
Funder: Marsden Fund
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