1
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Takashima K, Nakamura S, Nagayama M, Marumoto S, Ishikawa F, Xie W, Nakanishi I, Muraoka O, Morikawa T, Tanabe G. Role of the thiosugar ring in the inhibitory activity of salacinol, a potent natural α-glucosidase inhibitor. RSC Adv 2024; 14:4471-4481. [PMID: 38312722 PMCID: PMC10835759 DOI: 10.1039/d3ra08485j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 01/23/2024] [Indexed: 02/06/2024] Open
Abstract
Herein, ring-cleaved (24) and truncated (25) analogues of an azasugar, 1-deoxynojirimycin (23), exhibited inhibitory activity (Ki = 4-10 μM) equal to that of the parent compound (1, Ki = 14 μM). Based on this structure-activity relationship (SAR), four ring-cleaved (26a-26c and 27c) and three truncated (28a-28c) analogues of salacinol (1), a potent thiosugar-ring-containing α-glucosidase inhibitor, were synthesised. Bioassay results revealed that all the synthetics were inactive, indicating that the 5-membered thiosugar ring of 1 played an essential role in the potent activities of sulfonium-type inhibitors. The present findings are interesting and important in understanding the function of salacinol, considering that the observed inhibitory activity trend was contrary to the SAR observed in aza-compounds (23, 24, and 25) in a previous study, which suggested that the cyclic structure did not contribute to their strong inhibitory activity.
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Affiliation(s)
- Katsuki Takashima
- Faculty of Pharmacy, Kindai University 3-4-1 Kowakae, Higashi-osaka Osaka 577-8502 Japan
| | - Shinya Nakamura
- Faculty of Pharmacy, Kindai University 3-4-1 Kowakae, Higashi-osaka Osaka 577-8502 Japan
| | - Maiko Nagayama
- Faculty of Pharmacy, Kindai University 3-4-1 Kowakae, Higashi-osaka Osaka 577-8502 Japan
| | - Shinsuke Marumoto
- Joint Research Centre, Kindai University 3-4-1 Kowakae, Higashi-osaka Osaka 577-8502 Japan
| | - Fumihiro Ishikawa
- Faculty of Pharmacy, Kindai University 3-4-1 Kowakae, Higashi-osaka Osaka 577-8502 Japan
| | - Weijia Xie
- State Key Laboratory of Natural Medicines, Department of Medicinal Chemistry, China Pharmaceutical University Nanjing 2100009 P. R. China
| | - Isao Nakanishi
- Faculty of Pharmacy, Kindai University 3-4-1 Kowakae, Higashi-osaka Osaka 577-8502 Japan
| | - Osamu Muraoka
- Pharmaceutical Research and Technology Institute, Kindai University 3-4-1 Kowakae, Higashi-osaka Osaka 577-8502 Japan
| | - Toshio Morikawa
- Pharmaceutical Research and Technology Institute, Kindai University 3-4-1 Kowakae, Higashi-osaka Osaka 577-8502 Japan
| | - Genzoh Tanabe
- Faculty of Pharmacy, Kindai University 3-4-1 Kowakae, Higashi-osaka Osaka 577-8502 Japan
- Pharmaceutical Research and Technology Institute, Kindai University 3-4-1 Kowakae, Higashi-osaka Osaka 577-8502 Japan
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2
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Zhang X, Zhang L, Zhang B, Liu K, Sun J, Li Q, Zhao L. Herbal tea, a novel adjuvant therapy for treating type 2 diabetes mellitus: A review. Front Pharmacol 2022; 13:982387. [PMID: 36249806 PMCID: PMC9561533 DOI: 10.3389/fphar.2022.982387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/30/2022] [Indexed: 11/29/2022] Open
Abstract
Type 2 diabetes mellitus (T2DM) is a metabolic, endocrine disease characterized by persistent hyperglycemia. Several studies have shown that herbal tea improves glucose metabolism disorders in patients with T2DM. This study summarizes the published randomized controlled trials (RCTs) on herbal tea as a adjuvant therapy for treating T2DM and found that herbal teas have potential add-on effects in lowering blood glucose levels. In addition, we discussed the polyphenol contents in common herbal teas and their possible adverse effects. To better guide the application of herbal teas, we further summarized the hypoglycemic mechanisms of common herbal teas, which mainly involve: 1) improving insulin resistance, 2) protecting islet β-cells, 3) anti-inflammation and anti-oxidation, 4) inhibition of glucose absorption, and 5) suppression of gluconeogenesis. In conclusion, herbal tea, as a novel adjuvant therapy for treating T2DM, has the potential for further in-depth research and product development.
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Affiliation(s)
- Xiangyuan Zhang
- Department of Institute of Metabolic Diseases, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- Graduate College, Beijing University of Traditional Chinese Medicine, Beijing, China
| | - Lili Zhang
- Department of Institute of Metabolic Diseases, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Boxun Zhang
- Department of Institute of Metabolic Diseases, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Ke Liu
- Department of Institute of Metabolic Diseases, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Jun Sun
- Graduate College, Changchun University of Traditional Chinese Medicine, Jilin, China
| | - Qingwei Li
- Department of Institute of Metabolic Diseases, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- *Correspondence: Qingwei Li, ; Linhua Zhao,
| | - Linhua Zhao
- Department of Institute of Metabolic Diseases, Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China
- *Correspondence: Qingwei Li, ; Linhua Zhao,
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3
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Saeedi M, Raeisi-Nafchi M, Sobhani S, Mirfazli SS, Zardkanlou M, Mojtabavi S, Faramarzi MA, Akbarzadeh T. Synthesis of 4-alkylaminoimidazo[1,2-a]pyridines linked to carbamate moiety as potent α-glucosidase inhibitors. Mol Divers 2021; 25:2399-2409. [PMID: 33047276 DOI: 10.1007/s11030-020-10137-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Accepted: 08/25/2020] [Indexed: 02/05/2023]
Abstract
In this work, various imidazo[1,2-a]pyridines linked to carbamate moiety were designed, synthesized, and evaluated for their α-glucosidase inhibitory activity. Among synthesized compounds, 4-(3-(tert-Butylamino)imidazo[1,2-a]pyridin-2-yl)phenyl p-tolylcarbamate (6d) was the most potent compound (IC50 = 75.6 µM) compared with acarbose as the reference drug (IC50 = 750.0 µM). Kinetic study of compound 6d indicated a competitive inhibition. Also, the molecular docking study suggested desired interactions with the active site residues. In particular, hydrogen bonds and electrostatic interactions constructed by compound 6d afforded well-oriented conformation in the 3A4A active site.
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Affiliation(s)
- Mina Saeedi
- Medicinal Plants Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
- Persian Medicine and Pharmacy Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Maryam Raeisi-Nafchi
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Sepideh Sobhani
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyedeh Sara Mirfazli
- Department of Medicinal Chemistry, School of Pharmacy-International Campus, Iran University of Medical Sciences, Tehran, Iran
| | - Mahsa Zardkanlou
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
| | - Somayeh Mojtabavi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
| | - Mohammad Ali Faramarzi
- Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran, 1417614411, Iran
| | - Tahmineh Akbarzadeh
- Persian Medicine and Pharmacy Research Center, Tehran University of Medical Sciences, Tehran, Iran.
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.
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4
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Elongation of the side chain by linear alkyl groups increases the potency of salacinol, a potent α-glucosidase inhibitor from the Ayurvedic traditional medicine "Salacia," against human intestinal maltase. Bioorg Med Chem Lett 2020; 33:127751. [PMID: 33347966 DOI: 10.1016/j.bmcl.2020.127751] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/10/2020] [Accepted: 12/12/2020] [Indexed: 11/21/2022]
Abstract
Four chain-extended analogs (12a-12d) and two related de-O-sulfonated analogs (13a and 13c) by introducing alkyl groups (a: R = C3H7, b R = C6H13, c: R = C8H17, d: R = C10H21) to the side chains of salacinol (1), a natural α-glucosidase inhibitor from Ayurvedic traditional medicine "Salacia", were synthesized. The α-glucosidase inhibitory activities of all the synthesized analogs were evaluated in vitro. Against human intestinal maltase, the inhibitory activities of 12a and 13a with seven-carbon side chain were equal to that of 1. In contrast, analogs (12b-12d, and 13c) exhibited higher level of inhibitory activity against the same enzyme than 1 and had equal or higher potency than those of the clinically used anti-diabetics, voglibose, acarbose, and miglitol. Thus, elongation of the side chains of 1 was effective for specifically increasing the inhibitory activity against human intestinal maltase.
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5
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Sweet Selenium: Synthesis and Properties of Selenium-Containing Sugars and Derivatives. Pharmaceuticals (Basel) 2020; 13:ph13090211. [PMID: 32859124 PMCID: PMC7558951 DOI: 10.3390/ph13090211] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 08/19/2020] [Accepted: 08/25/2020] [Indexed: 02/07/2023] Open
Abstract
In the last decades, organoselenium compounds gained interest due to their important biological features. However, the lack of solubility, which characterizes most of them, makes their actual clinical exploitability a hard to reach goal. Selenosugars, with their intrinsic polarity, do not suffer from this issue and as a result, they can be conceived as a useful alternative. The aim of this review is to provide basic knowledge of the synthetic aspects of selenosugars, selenonium salts, selenoglycosides, and selenonucleotides. Their biological properties will be briefly detailed. Of course, it will not be a comprehensive dissertation but an analysis of what the authors think is the cream of the crop of this interesting research topic.
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6
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Wang L, Liang T, Fang Z. Chemical synthesis and preliminary biological evaluation of C-6-O-methyl-1-deoxynojirimycin as a potent α-glucosidase inhibitor. J Carbohydr Chem 2019. [DOI: 10.1080/07328303.2019.1700995] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Lin Wang
- School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing, P.R. China
| | - Tingting Liang
- College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, P.R. China
| | - Zhijie Fang
- School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing, P.R. China
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7
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Bagri P, Chester K, Khan W, Ahmad S. Aspects of extraction and biological evaluation of naturally occurring sugar-mimicking sulfonium-ion and their synthetic analogues as potent α-glucosidase inhibitors from Salacia: a review. RSC Adv 2017. [DOI: 10.1039/c7ra02955a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
A review of the selective inhibitory activities of sulfonium compounds ofSalaciaagainst intestinal α-glucosidases, structural features important for effective inhibition and the toggling approach for controlling starch digestion and glucose release.
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Affiliation(s)
- Priyanka Bagri
- School of Pharmaceutical Education and Research
- Bioactive Natural Product Laboratory
- Department of Pharmacognosy and Phytochemistry
- Jamia Hamdard
- New Delhi
| | | | - Washim Khan
- School of Pharmaceutical Education and Research
- Bioactive Natural Product Laboratory
- Department of Pharmacognosy and Phytochemistry
- Jamia Hamdard
- New Delhi
| | - Sayeed Ahmad
- School of Pharmaceutical Education and Research
- Bioactive Natural Product Laboratory
- Department of Pharmacognosy and Phytochemistry
- Jamia Hamdard
- New Delhi
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8
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Rajasekaran P, Singh GP, Hassam M, Vankar YD. A Cascade “Prins-Pinacol-Type Rearrangement and C4-OBn Participation” on Carbohydrate Substrates: Synthesis of Bridged Tricyclic Ketals, Annulated Sugars and C2-Branched Heptoses. Chemistry 2016; 22:18383-18387. [DOI: 10.1002/chem.201604902] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Indexed: 12/25/2022]
Affiliation(s)
| | - Govind Pratap Singh
- Department of Chemistry; Indian Institute of Technology; Kanpur 208016 India
| | - Mohammad Hassam
- Department of Chemistry; Indian Institute of Technology; Kanpur 208016 India
| | - Yashwant D. Vankar
- Department of Chemistry; Indian Institute of Technology; Kanpur 208016 India
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9
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Jabeen F, Shehzadi SA, Fatmi MQ, Shaheen S, Iqbal L, Afza N, Panda SS, Ansari FL. Synthesis, in vitro and computational studies of 1,4-disubstituted 1,2,3-triazoles as potential α-glucosidase inhibitors. Bioorg Med Chem Lett 2016; 26:1029-1038. [DOI: 10.1016/j.bmcl.2015.12.033] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 12/01/2015] [Accepted: 12/10/2015] [Indexed: 12/22/2022]
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10
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Ansari AA, Rajasekaran P, Khan MM, Vankar YD. Bicyclic Hybrid Sugars as Glycosidase Inhibitors: Synthesis and Comparative Study of Inhibitory Activities of Fused Oxa-Oxa, Oxa-Aza, and Oxa-Carbasugar Hybrid Molecules. J Org Chem 2014; 79:1690-9. [DOI: 10.1021/jo402574h] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Alafia A. Ansari
- Department
of Chemistry, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
| | - Parasuraman Rajasekaran
- Department
of Chemistry, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
| | - M. Musawwer Khan
- Department
of Chemistry, Aligarh Muslim University, Aligarh, Uttar Pradesh 202002, India
| | - Yashwant D. Vankar
- Department
of Chemistry, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
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11
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New N-(phenoxydecyl)phthalimide derivatives displaying potent inhibition activity towards α-glucosidase. Bioorg Med Chem 2010; 18:5903-14. [DOI: 10.1016/j.bmc.2010.06.088] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 05/26/2010] [Accepted: 06/28/2010] [Indexed: 11/18/2022]
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12
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Sim L, Jayakanthan K, Mohan S, Nasi R, Johnston BD, Pinto BM, Rose DR. New glucosidase inhibitors from an ayurvedic herbal treatment for type 2 diabetes: structures and inhibition of human intestinal maltase-glucoamylase with compounds from Salacia reticulata. Biochemistry 2010; 49:443-51. [PMID: 20039683 DOI: 10.1021/bi9016457] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An approach to controlling blood glucose levels in individuals with type 2 diabetes is to target alpha-amylases and intestinal glucosidases using alpha-glucosidase inhibitors acarbose and miglitol. One of the intestinal glucosidases targeted is the N-terminal catalytic domain of maltase-glucoamylase (ntMGAM), one of the four intestinal glycoside hydrolase 31 enzyme activities responsible for the hydrolysis of terminal starch products into glucose. Here we present the X-ray crystallographic studies of ntMGAM in complex with a new class of alpha-glucosidase inhibitors derived from natural extracts of Salacia reticulata, a plant used traditionally in Ayuverdic medicine for the treatment of type 2 diabetes. Included in these extracts are the active compounds salacinol, kotalanol, and de-O-sulfonated kotalanol. This study reveals that de-O-sulfonated kotalanol is the most potent ntMGAM inhibitor reported to date (K(i) = 0.03 microM), some 2000-fold better than the compounds currently used in the clinic, and highlights the potential of the salacinol class of inhibitors as future drug candidates.
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Affiliation(s)
- Lyann Sim
- Ontario Cancer Institute and Department of Medical Biophysics, University of Toronto, 101 College Street, Toronto, ON, M5G 1L7 Canada
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13
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Stocker BL, Dangerfield EM, Win‐Mason AL, Haslett GW, Timmer MSM. Recent Developments in the Synthesis of Pyrrolidine‐Containing Iminosugars. European J Org Chem 2010. [DOI: 10.1002/ejoc.200901320] [Citation(s) in RCA: 153] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Bridget L. Stocker
- Malaghan Institute of Medical Research, P. O. Box 7060, Wellington, New Zealand
| | - Emma M. Dangerfield
- Malaghan Institute of Medical Research, P. O. Box 7060, Wellington, New Zealand
- School of Chemical and Physical Sciences, Victoria University of Wellington, P. O. Box 600, Wellington, New Zealand, Fax: +64‐4‐463‐5241
| | - Anna L. Win‐Mason
- Malaghan Institute of Medical Research, P. O. Box 7060, Wellington, New Zealand
- School of Chemical and Physical Sciences, Victoria University of Wellington, P. O. Box 600, Wellington, New Zealand, Fax: +64‐4‐463‐5241
| | - Gregory W. Haslett
- Malaghan Institute of Medical Research, P. O. Box 7060, Wellington, New Zealand
- School of Chemical and Physical Sciences, Victoria University of Wellington, P. O. Box 600, Wellington, New Zealand, Fax: +64‐4‐463‐5241
| | - Mattie S. M. Timmer
- School of Chemical and Physical Sciences, Victoria University of Wellington, P. O. Box 600, Wellington, New Zealand, Fax: +64‐4‐463‐5241
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14
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Mohan S, Pinto BM. Towards the elusive structure of kotalanol, a naturally occurring glucosidase inhibitor. Nat Prod Rep 2010; 27:481-8. [PMID: 20336233 DOI: 10.1039/b925950c] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This Highlight describes the detailed approach used to determine the absolute stereochemistry of the stereogenic centers in the acyclic side chain of kotalanol, a naturally occurring glucosidase inhibitor isolated from the plant Salacia reticulata. The plant extract itself is used in Ayurvedic medicine for the treatment of Type 2 diabetes. We highlight the syntheses of proposed candidates based on structure-activity relationships, the total synthesis of kotalanol, and crystallographic studies of kotalanol and its de-O-sulfonated derivative complexed with recombinant human maltase glucoamylase (MGA), a critical intestinal glucosidase involved in the breakdown of glucose oligomers into glucose.
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Affiliation(s)
- Sankar Mohan
- Department of Chemistry, Simon Fraser University, Burnaby, B.C., Canada
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15
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Mohan S, Jayakanthan K, Nasi R, Kuntz DA, Rose DR, Pinto BM. Synthesis and Biological Evaluation of Heteroanalogues of Kotalanol and De-O-Sulfonated Kotalanol. Org Lett 2010; 12:1088-91. [DOI: 10.1021/ol100080m] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sankar Mohan
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6, Department of Medical Biophysics, University of Toronto and Division of Molecular and Structural Biology, Ontario Cancer Institute, Toronto, ON, Canada M5G 2M9, and Department of Biology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - Kumarasamy Jayakanthan
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6, Department of Medical Biophysics, University of Toronto and Division of Molecular and Structural Biology, Ontario Cancer Institute, Toronto, ON, Canada M5G 2M9, and Department of Biology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - Ravindranath Nasi
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6, Department of Medical Biophysics, University of Toronto and Division of Molecular and Structural Biology, Ontario Cancer Institute, Toronto, ON, Canada M5G 2M9, and Department of Biology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - Douglas A. Kuntz
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6, Department of Medical Biophysics, University of Toronto and Division of Molecular and Structural Biology, Ontario Cancer Institute, Toronto, ON, Canada M5G 2M9, and Department of Biology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - David R. Rose
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6, Department of Medical Biophysics, University of Toronto and Division of Molecular and Structural Biology, Ontario Cancer Institute, Toronto, ON, Canada M5G 2M9, and Department of Biology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
| | - B. Mario Pinto
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6, Department of Medical Biophysics, University of Toronto and Division of Molecular and Structural Biology, Ontario Cancer Institute, Toronto, ON, Canada M5G 2M9, and Department of Biology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
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16
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Wu SF, Ruan YP, Zheng X, Huang PQ. Samarium diiodide-mediated reductive couplings of chiral nitrones with aldehydes/ketones and acyl chlorides. Tetrahedron 2010. [DOI: 10.1016/j.tet.2010.01.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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17
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Wardrop DJ, Waidyarachchi SL. Synthesis and biological activity of naturally occurring α-glucosidase inhibitors. Nat Prod Rep 2010; 27:1431-68. [DOI: 10.1039/b914958a] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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18
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Mohan S, Pinto BM. Sulfonium-ion glycosidase inhibitors isolated from Salacia species used in traditional medicine, and related compounds. ACTA ACUST UNITED AC 2009. [DOI: 10.1135/cccc2009024] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A novel class of naturally-occurring glycosidase inhibitors, having sulfonium sulfate structures, has been isolated as bioactive components from Indian plants, belonging to the Salacia genus in the family Celastraceae, and used in Ayurvedic medicine for the treatment of type-2 diabetes. Thus far, five such sulfonium salts, namely, salacinol, kotalanol, salaprinol, ponkoranol and de-O-sulfonated kotalanol, have been isolated from this plant species. These structurally unique zwitterionic glycosidase inhibitors have received much attention due to their therapeutic potential in the treatment of type-2 diabetes. We recently reported a review article which focused mainly on salacinol and related analogues. The present review presents an update on the remaining four compounds from this class of glycosidase inhibitors, with respect to their isolation, glucosidase inhibitory activities, and synthesis. In addition, progress towards the stereochemical structure elucidation of kotalanol, through synthesis of analogues, is described. Review with 42 references.
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19
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Jayakanthan K, Mohan S, Pinto BM. Structure Proof and Synthesis of Kotalanol and De-O-sulfonated Kotalanol, Glycosidase Inhibitors Isolated from an Herbal Remedy for the Treatment of Type-2 Diabetes. J Am Chem Soc 2009; 131:5621-6. [DOI: 10.1021/ja900867q] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kumarasamy Jayakanthan
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
| | - Sankar Mohan
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
| | - B. Mario Pinto
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
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20
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Im R, Mano H, Matsuura T, Nakatani S, Shimizu J, Wada M. Mechanisms of blood glucose-lowering effect of aqueous extract from stems of Kothala himbutu (Salacia reticulata) in the mouse. JOURNAL OF ETHNOPHARMACOLOGY 2009; 121:234-240. [PMID: 19028559 DOI: 10.1016/j.jep.2008.10.026] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2007] [Revised: 09/08/2008] [Accepted: 10/23/2008] [Indexed: 05/27/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Kothala himbutu (Salacia reticulata) is a medicinal plant that has been used in Ayurvedic system of Indian and Sri Lankan traditional medicine to treat diabetes. AIM OF THE STUDY This study aimed to clarify the mechanism(s) by which aqueous extracts of Kothala himbutu (KTE) stems decreases fasting blood glucose levels. MATERIALS AND METHODS Gene expression profiles were assessed by DNA microarray and RT-PCR analyses of RNA from the liver of KK-Ay diabetic mice administered KTE or control distilled water for 4 weeks, and from cultured liver cells treated with freeze-dried KTE (KTED) or selected phenolic compounds. RESULTS DNA microarray and RT-PCR analyses revealed that gluconeogenic fructose-1,6-bisphosphatase (FBP) was decreased compared with the control in KTE-treated KK-Ay mice. RT-PCR analysis using cultured liver cells treated with KTED and/or actinomycin D or cycloheximide, revealed that KTED directly decreased FBP mRNA levels via destabilization of the mRNA. One compound in KTE, mangiferin, was demonstrated to dose-dependently down-regulate FBP mRNA. CONCLUSIONS These findings suggest that the mangiferin in KTE acts directly on liver cells and down-regulates the gluconeogenic pathway through regulation of FBP expression, thereby decreasing fasting blood glucose levels in mice. Our results demonstrate that gluconeogenic gene regulation is one possible mechanism by which KT exerts its effects in traditional diabetic medicine.
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Affiliation(s)
- Ryanghyok Im
- Department of Clinical Dietetics and Human Nutrition, Faculty of Pharmaceutical Sciences, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japan
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Nasi R, Patrick BO, Sim L, Rose DR, Pinto BM. Studies directed toward the stereochemical structure determination of the naturally occurring glucosidase inhibitor, kotalanol: synthesis and inhibitory activities against human maltase glucoamylase of seven-carbon, chain-extended homologues of salacinol. J Org Chem 2008; 73:6172-81. [PMID: 18651773 DOI: 10.1021/jo800855n] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The synthesis of new seven-carbon, chain-extended sulfonium salts of 1,4-anhydro-4-thio- d-arabinitol, analogues of the naturally occurring glycosidase inhibitor salacinol, are described. These compounds were designed on the basis of the structure activity data of chain-extended analogues of salacinol, with the intention of determining the hitherto unknown stereochemical structure of kotalanol, the naturally occurring seven-carbon chain-extended analogue of salacinol. The target zwitterionic compounds were synthesized by means of nucleophilic attack of the PMB-protected 1,4-anhydro-4-thio- d-arabinitols at the least hindered carbon atom of two 1,3-cyclic sulfates differing in stereochemistry at only one stereogenic center. The desired cyclic sulfates were synthesized starting from d-glucose via Wittig olefination and Sharpless asymmetric dihydroxylation. Deprotection of the coupled products by using a two-step sequence afforded two sulfonium sulfates. Optical rotation data for one of our compounds indicated a correspondence with that reported for kotalanol. However, comparison of (1)H and (13)C NMR spectral data of the synthetic compounds with those of kotalanol indicated discrepancies. The collective data from this and published work were used to propose a tentative structure for the naturally occurring compound, kotalanol. Comparison of physical data of previously synthesized analogues with those for the recently isolated six-carbon chain analogue, ponkoranol or reticulanol, also led to elucidation of this structure. Interestingly, both our compounds inhibited recombinant human maltase glucoamylase (MGA), as expected from our previous structure activity studies of lower homologues, with K i values of 0.13 +/- 0.02 and 0.10 +/- 0.02 microM.
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Affiliation(s)
- Ravindranath Nasi
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
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22
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Park H, Hwang KY, Kim YH, Oh KH, Lee JY, Kim K. Discovery and biological evaluation of novel alpha-glucosidase inhibitors with in vivo antidiabetic effect. Bioorg Med Chem Lett 2008; 18:3711-5. [PMID: 18524587 DOI: 10.1016/j.bmcl.2008.05.056] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2008] [Revised: 05/14/2008] [Accepted: 05/15/2008] [Indexed: 11/15/2022]
Abstract
Discovery of alpha-glucosidase inhibitors has been actively pursued with the aim to develop therapeutics for the treatment of diabetes and the other carbohydrate-mediated diseases. We have identified four novel alpha-glucosidase inhibitors by means of a drug design protocol involving the structure-based virtual screening under consideration of the effects of ligand solvation in the scoring function and in vitro enzyme assay. Because the newly identified inhibitors reveal in vivo antidiabetic activity as well as a significant potency with more than 70% inhibition of the catalytic activity of alpha-glucosidase at 50 microM, all of them seem to deserve further development to discover new drugs for diabetes. Structural features relevant to the interactions of the newly identified inhibitors with the active site residues of alpha-glucosidase are discussed in detail.
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Affiliation(s)
- Hwangseo Park
- Department of Bioscience and Biotechnology, Sejong University, 98 Kunja-Dong, Kwangjin-Ku, Seoul 143-747, Republic of Korea.
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Toward the Virtual Screening of α-Glucosidase Inhibitors with the Homology-Modeled Protein Structure. B KOREAN CHEM SOC 2008. [DOI: 10.5012/bkcs.2008.29.5.921] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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24
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Sim L, Quezada-Calvillo R, Sterchi EE, Nichols BL, Rose DR. Human Intestinal Maltase–Glucoamylase: Crystal Structure of the N-Terminal Catalytic Subunit and Basis of Inhibition and Substrate Specificity. J Mol Biol 2008; 375:782-92. [DOI: 10.1016/j.jmb.2007.10.069] [Citation(s) in RCA: 187] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2007] [Revised: 10/24/2007] [Accepted: 10/26/2007] [Indexed: 01/22/2023]
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25
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Park H, Hwang KY, Oh KH, Kim YH, Lee JY, Kim K. Discovery of novel alpha-glucosidase inhibitors based on the virtual screening with the homology-modeled protein structure. Bioorg Med Chem 2007; 16:284-92. [PMID: 17920282 DOI: 10.1016/j.bmc.2007.09.036] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2007] [Revised: 09/17/2007] [Accepted: 09/19/2007] [Indexed: 10/22/2022]
Abstract
Discovery of alpha-glucosidase inhibitors has been actively pursued with the aim to develop therapeutics for the treatment of diabetes and the other carbohydrate mediated diseases. We have been able to identify 13 novel alpha-glucosidase inhibitors by means of a computer-aided drug design protocol involving homology modeling of the target protein and the virtual screening with docking simulations under consideration of the effects of ligand solvation in the binding free energy function. Because the newly discovered inhibitors are structurally diverse and reveal a significant potency with IC(50) values lower than 50 microM, all of them can be considered for further development by structure-activity relationship studies or de novo design methods. Structural features relevant to the interactions of the newly identified inhibitors with the active site residues of alpha-glucosidase are discussed in detail.
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Affiliation(s)
- Hwangseo Park
- Department of Bioscience and Biotechnology, Sejong University, 98 Kunja-Dong, Kwangjin-Ku, Seoul 143-747, Republic of Korea.
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26
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Bhat RG, Kumar NS, Pinto BM. Synthesis of phosphate derivatives related to the glycosidase inhibitor salacinol. Carbohydr Res 2007; 342:1934-42. [PMID: 17572396 DOI: 10.1016/j.carres.2007.05.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2007] [Revised: 05/23/2007] [Accepted: 05/25/2007] [Indexed: 10/23/2022]
Abstract
The syntheses of polyhydroxylated imino- and anhydro thio-alditol compounds related to the naturally occurring glycosidase inhibitor, salacinol, containing a phosphate group in the side chain are described. The compounds lack hydroxyl groups on the acyclic side chain and are prototypes of the exact salacinol analogue. The synthetic strategy relies on the Mitsunobu reaction of N- and S-hydroxyalkyl derivatives of 2,3,5-tri-O-benzyl-1,4-dideoxy-1,4-imino-D-arabinitol and 1,4-anhydro-2,3,5-tri-O-benzyl-1-thio-D-arabinitol with dibenzyl phosphate to yield the corresponding protected heteroalditol phosphates. Screening of these compounds against recombinant human maltase glucoamylase (MGA), a critical intestinal glucosidase involved in the processing of oligosaccharides of glucose into glucose itself, shows that they are not effective inhibitors of MGA and demonstrates the importance of the hydroxyl and/or sulfate substituents present on the side chain for effective inhibition. The attempted synthesis of the exact analogue of salacinol by opening of cyclic phosphates is also described.
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Affiliation(s)
- Ramakrishna G Bhat
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
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27
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Chen W, Sim L, Rose DR, Pinto BM. Synthesis of analogues of salacinol containing a carboxylate inner salt and their inhibitory activities against human maltase glucoamylase. Carbohydr Res 2007; 342:1661-7. [PMID: 17597595 DOI: 10.1016/j.carres.2007.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2007] [Revised: 06/02/2007] [Accepted: 06/02/2007] [Indexed: 10/23/2022]
Abstract
The syntheses of analogues of the naturally occurring glycosidase inhibitor, salacinol, containing a carboxylate inner salt are described. Salacinol is a sulfonium ion with an internal sulfate counterion. The synthetic strategy relies on the nucleophilic attack of 1,4-anhydro-2,3,5-tri-O-benzyl-4-thio-D- or L-arabinitol at the least hindered carbon of 4,5-anhydro-2,3-O-isopropylidene-D-ribonic acid benzyl ester to yield coupled adducts. Deprotection of the coupled products gives the target compounds. The compound derived from D-arabinitol inhibits recombinant human maltase glucoamylase, one of the key intestinal enzymes involved in the breakdown of glucose oligosaccharides in the small intestine, with a Ki value of 10+/-1 microM.
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Affiliation(s)
- Wang Chen
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
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Nasi R, Sim L, Rose DR, Pinto BM. Synthesis and glycosidase inhibitory activities of chain-modified analogues of the glycosidase inhibitors salacinol and blintol. Carbohydr Res 2007; 342:1888-94. [PMID: 17359953 DOI: 10.1016/j.carres.2007.02.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2007] [Revised: 02/14/2007] [Accepted: 02/19/2007] [Indexed: 11/16/2022]
Abstract
The synthesis of chain-modified analogues of the naturally-occurring glycosidase inhibitor, salacinol, and its selenium analogue, blintol is described. The modification consists of a frame shift of the sulfate moiety by one carbon atom in the zwitterionic structures as well as an extension of the acyclic chain to five carbons. The target molecules were synthesized by alkylation of 1,4-anhydro-2,3,5-tri-O-p-methoxybenzyl-4-thio (or seleno)-D-arabinitol at the ring heteroatom by 2,3,5-tri-O-p-methoxybenzyl D- or L-xylitol-1,4-cyclic sulfate, followed by deprotection with trifluoroacetic acid. Two of the four compounds inhibit recombinant human maltase glucoamylase, one of the key intestinal enzymes involved in the breakdown of glucose oligosaccharides in the small intestine, with Ki values of 20+/-4 and 53+/-5 microM.
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Affiliation(s)
- Ravindranath Nasi
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
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Mohan S, Pinto BM. Zwitterionic glycosidase inhibitors: salacinol and related analogues. Carbohydr Res 2007; 342:1551-80. [PMID: 17559821 DOI: 10.1016/j.carres.2007.05.014] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2007] [Revised: 05/01/2007] [Accepted: 05/08/2007] [Indexed: 11/24/2022]
Abstract
Natural products with interesting biological properties and structural diversity have often served as valuable lead drug candidates for the treatment of human diseases. Salacinol, a naturally occurring alpha-glucosidase inhibitor, was shown to be one of the active principles of the aqueous extract of a medicinal plant that has been prescribed traditionally as an Ayurvedic treatment for type II diabetes. Salacinol contains an intriguing zwitterionic sulfonium-sulfate structure that comprises a 1,4-anhydro-4-thio-D-arabinitol core and a polyhydroxylated acyclic chain. Due to the unique structural features and its potential to become a lead drug candidate in the treatment of type II diabetes, a great deal of attention has been focused on salacinol and its analogues. Since the isolation of salacinol, several papers describing various synthetic routes to salacinol and its analogues have appeared in the literature. This review is aimed at highlighting the synthetic aspects of salacinol and related compounds as well as their structure-activity relationship studies.
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Affiliation(s)
- Sankar Mohan
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
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30
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Chen W, Kuntz DA, Hamlet T, Sim L, Rose DR, Mario Pinto B. Synthesis, enzymatic activity, and X-ray crystallography of an unusual class of amino acids. Bioorg Med Chem 2006; 14:8332-40. [PMID: 17010621 DOI: 10.1016/j.bmc.2006.09.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Revised: 08/28/2006] [Accepted: 09/07/2006] [Indexed: 11/23/2022]
Abstract
The synthesis of two novel amino acids, nitrogen analogues of the naturally occurring glycosidase inhibitor, salacinol, containing a carboxylate inner salt are described, along with the crystal structure of one of these analogues in the active site of Drosophila melanogaster Golgi mannosidase II (dGMII). Salacinol, a naturally occurring sulfonium ion, is one of the active principals in the aqueous extracts of Salacia reticulata that are traditionally used in Sri Lanka and India for the treatment of diabetes. The synthetic strategy relies on the nucleophilic attack of 2,3,5-tri-O-benzyl-1,4-dideoxy-1,4-imino l- or d-arabinitol at the least hindered carbon of 5,6-anhydro-2,3-di-O-benzyl-l-ascorbic acid to yield coupled adducts. Deprotection, stereoselective catalytic reduction, and hydrolysis of the coupled products give the target compounds. The compound derived from d-arabinitol inhibits dGMII, one of the critical enzymes in the glycoprotein processing pathway, with an IC(50) of 0.3mM. Inhibition of GMII has been identified as a target for control of metastatic cancer. An X-ray crystal structure of the complex of this compound with dGMII provides insight into the requirements for an effective inhibitor. The same compound inhibits recombinant human maltase glucoamylase, one of the key intestinal enzymes involved in the breakdown of glucose oligosaccharides in the small intestine, with a K(i) value of 21microM.
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Affiliation(s)
- Wang Chen
- Department of Chemistry, Simon Fraser University, Burnaby, BC, Canada V5A 1S6
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31
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Gu G, Liu H, Pinto BM. Facile synthesis of sulfonium ion derivatives of 1,5-anhydro-5-thio-l-fucitol as potential α-l-fucosidase inhibitors. Carbohydr Res 2006; 341:2478-86. [PMID: 16930571 DOI: 10.1016/j.carres.2006.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Revised: 07/31/2006] [Accepted: 08/02/2006] [Indexed: 11/24/2022]
Abstract
Five sulfonium ion derivatives with 1,5-anhydro-5-thio-L-fucitol as a core structure were efficiently synthesized as potential alpha-L-fucosidase inhibitors. The key unit, the tri-O-benzyl derivative of L-fucitol, was readily synthesized from methyl alpha-D-mannopyranoside. Alkylation with methyl iodide or 5-methoxycarbonyl-1-pentyl iodide in acetonitrile containing AgBF4 afforded the corresponding alkylated sulfonium tetrafluoroborates. Alternatively, ring opening of three 1,3-cyclic sulfates in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) containing K2CO3 afforded the corresponding zwitterionic sulfonium sulfates.
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Affiliation(s)
- Guofeng Gu
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
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32
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Nasi R, Pinto BM. Synthesis of new analogues of salacinol containing a pendant hydroxymethyl group as potential glycosidase inhibitors. Carbohydr Res 2006; 341:2305-11. [PMID: 16854397 DOI: 10.1016/j.carres.2006.06.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2006] [Revised: 06/20/2006] [Accepted: 06/28/2006] [Indexed: 11/23/2022]
Abstract
The synthesis of new analogues of the naturally occurring glycosidase inhibitor, salacinol, and its ammonium analogue, ghavamiol is described. These analogues contain an additional hydroxymethyl group at C-1, which was intended to form additional polar contacts within the active site of glycosidase enzymes. The target zwitterionic compounds were synthesized by means of nucleophilic attack at the least hindered carbon atom of 2,4-O-benzylidene-l (or d)-erythritol 1,3-cyclic sulfate by 2,5-anhydro-1,3:4,6-di-O-benzylidene-2,5-dideoxy-5-thio (or 1,5-imino)-l-iditol.
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Affiliation(s)
- Ravindranath Nasi
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6
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