1
|
Xie Y, Zhang Z, Zhang B, He N, Peng M, Song S, Wang B, Yu F. Oxidative Free-Radical C(sp 2)-H Bond Chlorination of Enaminones with LiCl: Access to Highly Functionalized α-Chlorinated Enaminones. J Org Chem 2024; 89:8521-8530. [PMID: 38828704 DOI: 10.1021/acs.joc.4c00456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
An oxidative free-radical C(sp2)-H bond chlorination strategy of enaminones has been developed by using LiCl as a chlorinating reagent and K2S2O8 as an oxidant. This transformation provides a new and straightforward synthetic methodology to afford highly functionalized α-chlorinated enaminones with a Z-configuration in good to excellent yields.
Collapse
Affiliation(s)
- Yunhua Xie
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, P. R. China
| | - Zhilai Zhang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, P. R. China
| | - Biao Zhang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, P. R. China
| | - Nengqin He
- Yunnan Key Laboratory for Pollution Processes and Control of Plateau Lake-Watersheds, Yunnan Academy of Ecological and Environmental Sciences, Kunming 650500, P. R. China
| | - Menglin Peng
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, P. R. China
| | - Siyu Song
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, P. R. China
| | - Baoqu Wang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, P. R. China
| | - Fuchao Yu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, P. R. China
| |
Collapse
|
2
|
Buntasana S, Padungros P. Glycosylation of n-pentenyl glycosides using bromodiethylsulfonium salt as an activator: interception of the glycosyl intermediate by chloride ion transfer. Org Biomol Chem 2023; 22:126-143. [PMID: 38051124 DOI: 10.1039/d3ob01618h] [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: 12/07/2023]
Abstract
Utilization of n-pentenyl glycosides (NPGs) in modern carbohydrate synthesis may be hindered by their sluggish activation, which results from reversible halogenation and cyclization processes. Bromodiethylsulfonium bromopentachloroantimonate (BDSB) has been previously shown to be a powerful brominating agent for the cation-π polyene cyclization of less reactive and electron-poor polyenes. This study demonstrates the activation of NPGs using BDSB as a powerful brominating agent. BDSB effectively activates the terminal olefins of NPGs and the reaction proceeds through 5-exo-tet cyclization, offering a rapid and mild approach for glycosylation with a wide range of glycosyl donors, including n-pentenyl mannoside, n-pentenyl galactoside, and n-pentenyl glucoside. The success of this approach derives from the chloride ion transfer from the nonnucleophilic SbCl5Br anion to the glycosyl intermediate, which disrupts the equilibrium and produces a glycosyl chloride intermediate that is smoothly converted to 22 coupling products, with yields ranging from moderate to excellent (49-100%). The β-selective glycosylation is accomplished when employing NPGs equipped with a neighboring participating group. The practicality of the BDSB-activated glycosylation is demonstrated by a gram-scale synthesis. This study showcases BDSB as a potent activator for NPG glycosylation through the interception of a glycosyl intermediate that diminishes the equilibration during halogenation and 5-exo-tet cyclization.
Collapse
Affiliation(s)
- Supanat Buntasana
- Green Chemistry for Fine Chemical Production and Environmental Remediation Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok 10330, Thailand.
| | - Panuwat Padungros
- Green Chemistry for Fine Chemical Production and Environmental Remediation Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok 10330, Thailand.
| |
Collapse
|
3
|
Khanam A, Dubey S, Mandal PK. Mild method for the synthesis of α-glycosyl chlorides: A convenient protocol for quick one-pot glycosylation. Carbohydr Res 2023; 534:108976. [PMID: 37871478 DOI: 10.1016/j.carres.2023.108976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 10/17/2023] [Accepted: 10/18/2023] [Indexed: 10/25/2023]
Abstract
A simple and efficient protocol for the preparation of α-glycosyl chlorides within 15-30 min is described which employs a stable, cheap, and commercially available Trichloroisocyanuric acid (TCCA) as non-toxic chlorinating agent along with PPh3. This process involved a wide range of substrate scope and is well-suited with labile hydroxyl protecting groups such as benzyl, acetyl, benzoyl, isopropylidene, benzylidene, and TBDPS (tert-butyldiphenylsilyl) groups. This process is operationally simple, mild conditions and obtained good yields with excellent α selectivity. Moreover, a multi-catalyst one-pot glycosylation can be carried out to transform the glycosyl hemiacetals directly to a various O-glycosides in high overall yields without the need for separation or purification of the α-glycosyl chloride donors.
Collapse
Affiliation(s)
- Ariza Khanam
- Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, BS-10/1, Sector 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow, 226 031, India
| | - Shashiprabha Dubey
- Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, BS-10/1, Sector 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow, 226 031, India
| | - Pintu Kumar Mandal
- Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, BS-10/1, Sector 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow, 226 031, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
| |
Collapse
|
4
|
Le HT, Liu M, Grimes CL. Application of bioanalytical and computational methods in decoding the roles of glycans in host-pathogen interactions. Curr Opin Chem Biol 2023; 74:102301. [PMID: 37080155 PMCID: PMC10296625 DOI: 10.1016/j.cbpa.2023.102301] [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: 12/05/2022] [Revised: 03/09/2023] [Accepted: 03/14/2023] [Indexed: 04/22/2023]
Abstract
Host-pathogen interactions (HPIs) are complex processes that require tight regulation. A common regulatory mechanism of HPIs is through glycans of either host cells or pathogens. Due to their diverse sequences, complex structures, and conformations, studies of glycans require highly sensitive and powerful tools. Recent improvements in technology have enabled the application of many bioanalytical techniques and modeling methods to investigate glycans and their mechanisms in HPIs. This mini-review highlights how these advances have been used to understand the role glycans play in HPIs in the past 2 years.
Collapse
Affiliation(s)
- Ha T Le
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, USA
| | - Min Liu
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, USA
| | - Catherine L Grimes
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, USA; Department of Biological Sciences, University of Delaware, Newark, DE, USA.
| |
Collapse
|
5
|
Singh Y, Geringer SA, Demchenko AV. Synthesis and Glycosidation of Anomeric Halides: Evolution from Early Studies to Modern Methods of the 21st Century. Chem Rev 2022; 122:11701-11758. [PMID: 35675037 PMCID: PMC9417321 DOI: 10.1021/acs.chemrev.2c00029] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Advances in synthetic carbohydrate chemistry have dramatically improved access to common glycans. However, many novel methods still fail to adequately address challenges associated with chemical glycosylation and glycan synthesis. Since a challenge of glycosylation has remained, scientists have been frequently returning to the traditional glycosyl donors. This review is dedicated to glycosyl halides that have played crucial roles in shaping the field of glycosciences and continue to pave the way toward our understanding of chemical glycosylation.
Collapse
Affiliation(s)
- Yashapal Singh
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
| | - Scott A Geringer
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
| | - Alexei V Demchenko
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
- Department of Chemistry, Saint Louis University, 3501 Laclede Avenue, St. Louis, Missouri 63103, United States
| |
Collapse
|
6
|
Ye W, Stevens CM, Wen P, Simmons CJ, Tang W. Mild Cu(OTf) 2-Mediated C-Glycosylation with Chelation-Assisted Picolinate as a Leaving Group. J Org Chem 2020; 85:16218-16225. [PMID: 32691596 PMCID: PMC8138965 DOI: 10.1021/acs.joc.0c01041] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
C-Glycosylation reactions of glycosyl picolinates with allyltrimethylsilane or silyl enol ethers were developed. Picolinate as a chelation-assisted leaving group could be activated by Cu(OTf)2 and avoided the use of harsh Lewis acids. The glycosylations were operated under mild neutral conditions and gave the corresponding C-glycosides in up to 95% yield with moderate to excellent stereoselectivities.
Collapse
Affiliation(s)
- Wenjing Ye
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Christopher M Stevens
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Peng Wen
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Christopher J Simmons
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Weiping Tang
- School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| |
Collapse
|