1
|
Bharali MM, Santra A. Total Synthesis of 6-Deoxy-l-talose Containing a Pentasaccharide Repeating Unit of Acinetobacter baumannii K11 Capsular Polysaccharides. J Org Chem 2023; 88:8770-8780. [PMID: 37340701 DOI: 10.1021/acs.joc.3c00615] [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: 06/22/2023]
Abstract
Herein, we report a concise synthetic approach for the first total synthesis of a pentasaccharide repeating unit of Acinetobacter baumannii K11 capsular polysaccharides containing a rare sugar 6-deoxy-l-talose. The pentasaccharide was synthesized in a convergent manner using a [3 + 2] block glycosylation strategy. During this synthetic strive, we used a 2,2,2-trichloroethoxycarbonyl (Troc)-protected monosaccharide unit to achieve a high yield during the glycosylation to synthesize a trisaccharide, and chemoselective deprotection of the Troc group from the trisaccharide was carried out under a mild, pH-neutral condition, keeping the O-glycosidic bond, azido, and acid/base sensitive group intact. A thiotolylglycoside disaccharide donor containing 6-deoxy-l-talose was synthesized for the first time by the armed-disarmed glycosylation method between two thiotolylglycosides.
Collapse
Affiliation(s)
- Mrinmoy Manash Bharali
- Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Abhishek Santra
- Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Uppal Road, Hyderabad 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| |
Collapse
|
2
|
Geng W, Wang H, Xi J, Jiang R, Guo J, Jiao K, Tang M, Liu Q, Zhang L, Liu H. Palladium-catalyzed cascade cyclization of allenamide with 2-iodoanilines to access functionalized indoloquinolines. Org Biomol Chem 2023; 21:279-283. [PMID: 36484347 DOI: 10.1039/d2ob01770a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A novel and efficient palladium-catalyzed cascade cyclization to indoloquinoline derivatives in one pot has been developed by using allenamide derivatives and 2-iodoanilines as the key building blocks. The process involved two cyclizations: intramolecular cyclization/π-allylic substitution and intramolecular 6-endo Heck cyclization. Furthermore, dihydrobenzofuro[2,3-b]quinoline derivatives could also be achieved via this strategy using allenyl ethers instead of allenamides. The readily available substrates, mild conditions, high efficiency and step economy make this strategy a promising method in the synthesis of polycyclic motifs.
Collapse
Affiliation(s)
- Wenzhe Geng
- School of Chemistry & Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, P. R. China.
| | - Hui Wang
- School of Chemistry & Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, P. R. China. .,Shandong Jincheng Biopharmaceutical Co., Ltd., No. 3 Shuangshan Road of Xingshan, Zibo 255049, P. R. China
| | - Juan Xi
- School of Chemistry & Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, P. R. China.
| | - Ruonan Jiang
- School of Chemistry & Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, P. R. China.
| | - Jintao Guo
- School of Chemistry & Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, P. R. China.
| | - Keqiang Jiao
- School of Chemistry & Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, P. R. China.
| | - Mengyao Tang
- School of Chemistry & Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, P. R. China.
| | - Qing Liu
- School of Chemistry & Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, P. R. China.
| | - Lizhi Zhang
- School of Chemistry & Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, P. R. China.
| | - Hui Liu
- School of Chemistry & Chemical Engineering, Shandong University of Technology, 266 West Xincun Road, Zibo 255049, P. R. China. .,Shandong Jincheng Biopharmaceutical Co., Ltd., No. 3 Shuangshan Road of Xingshan, Zibo 255049, P. R. China
| |
Collapse
|
3
|
Dhara D, Dhara A, Murphy PV, Mulard LA. Protecting group principles suited to late stage functionalization and global deprotection in oligosaccharide synthesis. Carbohydr Res 2022; 521:108644. [PMID: 36030632 DOI: 10.1016/j.carres.2022.108644] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 07/28/2022] [Accepted: 07/31/2022] [Indexed: 11/02/2022]
Abstract
Chemical synthesis is a powerful tool to access homogeneous complex glycans, which relies on protecting group (PG) chemistry. However, the overall efficiency of chemical glycan assembly is still low when compared to oligonucleotide or oligopeptide synthesis. There have been many contributions giving rise to collective improvement in carbohydrate synthesis that includes PG manipulation and stereoselective glycoside formation and some of this chemistry has been transferred to the solid phase or adapted for programmable one pot synthesis approaches. However, after all glycoside bond formation reactions are completed, the global deprotection (GD) required to give the desired target OS can be challenging. Difficulties observed in the removal of permanent PGs to release the desired glycans can be due to the number and diversity of PGs present in the protected OSs, nature and structural complexity of glycans, etc. Here, we have reviewed the difficulties associated with the removal of PGs from densely protected OSs to obtain their free glycans. In particularly, this review focuses on the challenges associated with hydrogenolysis of benzyl groups, saponification of esters and functional group interconversion such as oxidation/reduction that are commonly performed in GD stage. More generally, problems observed in the removal of permanent PGs is reviewed herein, including benzyl, acyl (levulinoyl, acetyl), N-trichloroacetyl, N-2,2,2-trichloroethoxycarbonyl, N-phthaloyl etc. from a number of fully protected OSs to release the free sugar, that have been previously reported in the literature.
Collapse
Affiliation(s)
- Debashis Dhara
- Institut Pasteur, Université Paris Cité, CNRS UMR 3523, Unité de Chimie des Biomolécules, 25-28 rue du Dr Roux, 75015, Paris, France; School of Biological and Chemical Sciences, NUI Galway, University Road, Galway, H91 TK33, Ireland.
| | - Ashis Dhara
- School of Biological and Chemical Sciences, NUI Galway, University Road, Galway, H91 TK33, Ireland
| | - Paul V Murphy
- School of Biological and Chemical Sciences, NUI Galway, University Road, Galway, H91 TK33, Ireland; SSPC - The Science Foundation Ireland Research Centre for Pharmaceuticals, NUI Galway, University Road, Galway, H91 TK33, Ireland
| | - Laurence A Mulard
- Institut Pasteur, Université Paris Cité, CNRS UMR 3523, Unité de Chimie des Biomolécules, 25-28 rue du Dr Roux, 75015, Paris, France
| |
Collapse
|
4
|
Andler O, Kazmaier U. Total synthesis of apratoxin A and B using Matteson's homologation approach. Org Biomol Chem 2021; 19:4866-4870. [PMID: 33998628 DOI: 10.1039/d1ob00713k] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Apratoxin A and B, two members of an interesting class of marine cyclodepsipeptides are synthesized in a straightforward manner via Matteson homologation. Starting from a chiral boronic ester, the polyketide fragment of the apratoxins was obtained via five successive homologation steps in an overall yield of 27% and very good diastereoselectivity. This approach is highly flexible and should allow modification also of this part of the natural products, while previous modifications have been carried out mainly in the peptide fragment.
Collapse
Affiliation(s)
- Oliver Andler
- Organic Chemistry, Saarland University, P.O. Box 151150, 66041 Saarbrücken, Germany.
| | - Uli Kazmaier
- Organic Chemistry, Saarland University, P.O. Box 151150, 66041 Saarbrücken, Germany.
| |
Collapse
|
5
|
Affiliation(s)
- Jinseong Jeong
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, South Korea
- Center for Catalytic Hydrocarbon Functionalizations, Institute of Basic Science (IBS), Daejeon, 34126, South Korea
| | - Joon Heo
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, South Korea
- Center for Catalytic Hydrocarbon Functionalizations, Institute of Basic Science (IBS), Daejeon, 34126, South Korea
| | - Dongwook Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, South Korea
- Center for Catalytic Hydrocarbon Functionalizations, Institute of Basic Science (IBS), Daejeon, 34126, South Korea
| | - Sukbok Chang
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, South Korea
- Center for Catalytic Hydrocarbon Functionalizations, Institute of Basic Science (IBS), Daejeon, 34126, South Korea
| |
Collapse
|
6
|
Abstract
The protection of amino acid reactive functionalities including the α-amino group, the side chain (amines, carboxylic acids, alcohols, and thiols), or the carboxylic acid terminus is an essential strategy in peptide chemistry. This is mandatory to prevent polymerization of the amino acids and to minimize undesirable side reactions during the synthetic process. Proper protecting group manipulation strategies can maximize the yield of the desired product or allow the construction of complex peptide-based structures. Thus, the compatibility and orthogonality of each protecting group are key to achieve the proper control of molecular structure. Herein, we describe some common protecting groups and their general unmasking methods, in order to mask and expose amine, carboxylic acid, alcohol, and thiol functionalities to achieve the synthesis of peptides and related molecules.
Collapse
|