51
|
Li RZ, Tang H, Wan L, Zhang X, Fu Z, Liu J, Yang S, Jia D, Niu D. Site-Divergent Delivery of Terminal Propargyls to Carbohydrates by Synergistic Catalysis. Chem 2017. [DOI: 10.1016/j.chempr.2017.09.007] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
52
|
Manhas S, Taylor MS. Boronic Acids as Phase-Transfer Reagents for Fischer Glycosidations in Low-Polarity Solvents. J Org Chem 2017; 82:11406-11417. [DOI: 10.1021/acs.joc.7b01880] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Sanjay Manhas
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada
| | - Mark S. Taylor
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada
| |
Collapse
|
53
|
Abstract
The application of small molecules as catalysts for the diversification of natural product scaffolds is reviewed. Specifically, principles that relate to the selectivity challenges intrinsic to complex molecular scaffolds are summarized. The synthesis of analogues of natural products by this approach is then described as a quintessential "late-stage functionalization" exercise wherein natural products serve as the lead scaffolds. Given the historical application of enzymatic catalysts to the site-selective alteration of complex molecules, the focus of this Review is on the recent studies of nonenzymatic catalysts. Reactions involving hydroxyl group derivatization with a variety of electrophilic reagents are discussed. C-H bond functionalizations that lead to oxidations, aminations, and halogenations are also presented. Several examples of site-selective olefin functionalizations and C-C bond formations are also included. Numerous classes of natural products have been subjected to these studies of site-selective alteration including polyketides, glycopeptides, terpenoids, macrolides, alkaloids, carbohydrates, and others. What emerges is a platform for chemical remodeling of naturally occurring scaffolds that targets virtually all known chemical functionalities and microenvironments. However, challenges for the design of very broad classes of catalysts, with even broader selectivity demands (e.g., stereoselectivity, functional group selectivity, and site-selectivity) persist. Yet, a significant spectrum of powerful, catalytic alterations of complex natural products now exists such that expansion of scope seems inevitable. Several instances of biological activity assays of remodeled natural product derivatives are also presented. These reports may foreshadow further interdisciplinary impacts for catalytic remodeling of natural products, including contributions to SAR development, mode of action studies, and eventually medicinal chemistry.
Collapse
Affiliation(s)
- Christopher R. Shugrue
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
| | - Scott J. Miller
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
| |
Collapse
|
54
|
Tay JH, Argüelles AJ, DeMars MD, Zimmerman PM, Sherman DH, Nagorny P. Regiodivergent Glycosylations of 6-Deoxy-erythronolide B and Oleandomycin-Derived Macrolactones Enabled by Chiral Acid Catalysis. J Am Chem Soc 2017; 139:8570-8578. [PMID: 28627172 PMCID: PMC5553906 DOI: 10.1021/jacs.7b03198] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This work describes the first example of using chiral catalysts to control site-selectivity for the glycosylations of complex polyols such as 6-deoxyerythronolide B and oleandomycin-derived macrolactones. The regiodivergent introduction of sugars at the C3, C5, and C11 positions of macrolactones was achieved by selecting appropriate chiral acids as catalysts or through introduction of stoichiometric boronic acid-based additives. BINOL-based chiral phosphoric acids (CPAs) were used to catalyze highly selective glycosylations at the C5 positions of macrolactones (up to 99:1 rr), whereas the use of SPINOL-based CPAs resulted in selectivity switch and glycosylation of the C3 alcohol (up to 91:9 rr). Additionally, the C11 position of macrolactones was selectively functionalized through traceless protection of the C3/C5 diol with boronic acids prior to glycosylation. Investigation of the reaction mechanism for the CPA-controlled glycosylations revealed the involvement of covalently linked anomeric phosphates rather than oxocarbenium ion pairs as the reactive intermediates.
Collapse
Affiliation(s)
- Jia-Hui Tay
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109 United States
| | - Alonso J. Argüelles
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109 United States
| | - Matthew D. DeMars
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109 United States
| | - Paul M. Zimmerman
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109 United States
| | - David H. Sherman
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109 United States
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI 48109 United States
- Department of Microbiology & Immunology, University of Michigan, Ann Arbor, MI 48109 United States
| | - Pavel Nagorny
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109 United States
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI 48109 United States
| |
Collapse
|
55
|
Downey AM, Hocek M. Strategies toward protecting group-free glycosylation through selective activation of the anomeric center. Beilstein J Org Chem 2017; 13:1239-1279. [PMID: 28694870 PMCID: PMC5496566 DOI: 10.3762/bjoc.13.123] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 06/01/2017] [Indexed: 12/13/2022] Open
Abstract
Glycosylation is an immensely important biological process and one that is highly controlled and very efficient in nature. However, in a chemical laboratory the process is much more challenging and usually requires the extensive use of protecting groups to squelch reactivity at undesired reactive moieties. Nonetheless, by taking advantage of the differential reactivity of the anomeric center, a selective activation at this position is possible. As a result, protecting group-free strategies to effect glycosylations are available thanks to the tremendous efforts of many research groups. In this review, we showcase the methods available for the selective activation of the anomeric center on the glycosyl donor and the mechanisms by which the glycosylation reactions take place to illustrate the power these techniques.
Collapse
Affiliation(s)
- A Michael Downey
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nam. 2, 16610 Prague 6, Czech Republic
| | - Michal Hocek
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nam. 2, 16610 Prague 6, Czech Republic
- Department of Organic Chemistry, Faculty of Science, Charles University in Prague, 12843 Prague 2, Czech Republic
| |
Collapse
|
56
|
Park Y, Harper KC, Kuhl N, Kwan EE, Liu RY, Jacobsen EN. Macrocyclic bis-thioureas catalyze stereospecific glycosylation reactions. Science 2017; 355:162-166. [PMID: 28082586 PMCID: PMC5671764 DOI: 10.1126/science.aal1875] [Citation(s) in RCA: 187] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 12/06/2016] [Indexed: 01/10/2023]
Abstract
Carbohydrates are involved in nearly all aspects of biochemistry, but their complex chemical structures present long-standing practical challenges to their synthesis. In particular, stereochemical outcomes in glycosylation reactions are highly dependent on the steric and electronic properties of coupling partners; thus, carbohydrate synthesis is not easily predictable. Here we report the discovery of a macrocyclic bis-thiourea derivative that catalyzes stereospecific invertive substitution pathways of glycosyl chlorides. The utility of the catalyst is demonstrated in the synthesis of trans-1,2-, cis-1,2-, and 2-deoxy-β-glycosides. Mechanistic studies are consistent with a cooperative mechanism in which an electrophile and a nucleophile are simultaneously activated to effect a stereospecific substitution reaction.
Collapse
Affiliation(s)
- Yongho Park
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Kaid C Harper
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Nadine Kuhl
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Eugene E Kwan
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Richard Y Liu
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Eric N Jacobsen
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
| |
Collapse
|
57
|
Messina MS, Ko JH, Yang Z, Strouse MJ, Houk KN, Maynard HD. Effect of trehalose polymer regioisomers on protein stabilization. Polym Chem 2017. [DOI: 10.1039/c7py00700k] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Polymers with different trehalose side chain regioisomers were synthesized and compared for insulin stabilization.
Collapse
Affiliation(s)
- Marco S. Messina
- Department of Chemistry and Biochemistry
- University of California
- Los Angeles
- USA
- California NanoSystems Institute
| | - Jeong Hoon Ko
- Department of Chemistry and Biochemistry
- University of California
- Los Angeles
- USA
- California NanoSystems Institute
| | - Zhongyue Yang
- Department of Chemistry and Biochemistry
- University of California
- Los Angeles
- USA
- California NanoSystems Institute
| | - M. Jane Strouse
- Department of Chemistry and Biochemistry
- University of California
- Los Angeles
- USA
| | - K. N. Houk
- Department of Chemistry and Biochemistry
- University of California
- Los Angeles
- USA
- California NanoSystems Institute
| | - Heather D. Maynard
- Department of Chemistry and Biochemistry
- University of California
- Los Angeles
- USA
- California NanoSystems Institute
| |
Collapse
|
58
|
|
59
|
D’Angelo KA, Taylor MS. Borinic Acid Catalyzed Stereo- and Regioselective Couplings of Glycosyl Methanesulfonates. J Am Chem Soc 2016; 138:11058-66. [DOI: 10.1021/jacs.6b06943] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Kyan A. D’Angelo
- Department
of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Mark S. Taylor
- Department
of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| |
Collapse
|
60
|
Abstract
A robust platform for facile defined glycan synthesis does not exist. Yet the need for such technology has never been greater as researchers seek to understand the full scope of carbohydrate function, stretching beyond the classical roles of structure and energy storage to encompass highly nuanced cell signaling events. To comprehensively explore and exploit the full diversity of carbohydrate functions, we must first be able to synthesize them in a controlled manner. Toward this goal, traditional chemical syntheses are inefficient while nature's own synthetic enzymes, the glycosyl transferases, can be challenging to express and expensive to employ on scale. Glycoside hydrolases represent a pool of glycan processing enzymes that can be either used in a transglycosylation mode or, better, engineered to function as "glycosynthases," mutant enzymes capable of assembling glycosides. Glycosynthases grant access to valuable glycans that act as functional and structural probes or indeed as inhibitors and therapeutics in their own right. The remodelling of glycosylation patterns in therapeutic proteins via glycoside hydrolases and their mutants is an exciting frontier in both basic research and industrial scale processes.
Collapse
Affiliation(s)
- Phillip M. Danby
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stephen G. Withers
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
61
|
Wang PSP, Schepartz A. β-Peptide bundles: Design. Build. Analyze. Biosynthesize. Chem Commun (Camb) 2016; 52:7420-32. [PMID: 27146019 DOI: 10.1039/c6cc01546h] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Peptides containing β-amino acids are unique non-natural polymers known to assemble into protein-like tertiary and quaternary structures. When composed solely of β-amino acids, the structures formed, defined assemblies of 14-helices called β-peptide bundles, fold cooperatively in water solvent into unique and discrete quaternary assemblies that are highly thermostable, bind complex substrates and metal ion cofactors, and, in certain cases, catalyze chemical reactions. In this Perspective, we recount the design and elaboration of β-peptide bundles and provide an outlook on recent, unexpected discoveries that could influence research on β-peptides and β-peptide bundles (and β-amino acid-containing proteins) for decades to come.
Collapse
Affiliation(s)
- Pam S P Wang
- Department of Chemistry, Yale University, 225 Prospect St., New Haven, CT 06511, USA.
| | | |
Collapse
|