1
|
Wang Y, Shen XJ, Su FW, Xie YR, Wang LX, Zhang N, Wu YL, Niu Y, Zhang DY, Zi CT, Wang XJ, Sheng J. Novel Perbutyrylated Glucose Derivatives of (-)-Epigallocatechin-3-Gallate Inhibit Cancer Cells Proliferation by Decreasing Phosphorylation of the EGFR: Synthesis, Cytotoxicity, and Molecular Docking. Molecules 2021; 26:4361. [PMID: 34299635 PMCID: PMC8306927 DOI: 10.3390/molecules26144361] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 07/03/2021] [Accepted: 07/14/2021] [Indexed: 01/10/2023] Open
Abstract
Lung cancer is one of the most commonly occurring cancer mortality worldwide. The epidermal growth factor receptor (EGFR) plays an important role in cellular functions and has become the new promising target. Natural products and their derivatives with various structures, unique biological activities, and specific selectivity have served as lead compounds for EGFR. D-glucose and EGCG were used as starting materials. A series of glucoside derivatives of EGCG (7-12) were synthesized and evaluated for their in vitro anticancer activity against five human cancer cell lines, including HL-60, SMMC-7721, A-549, MCF-7, and SW480. In addition, we investigated the structure-activity relationship and physicochemical property-activity relationship of EGCG derivatives. Compounds 11 and 12 showed better growth inhibition than others in four cancer cell lines (HL-60, SMMC-7721, A-549, and MCF), with IC50 values in the range of 22.90-37.87 μM. Compounds 11 and 12 decreased phosphorylation of EGFR and downstream signaling protein, which also have more hydrophobic interactions than EGCG by docking study. The most active compounds 11 and 12, both having perbutyrylated glucose residue, we found that perbutyrylation of the glucose residue leads to increased cytotoxic activity and suggested that their potential as anticancer agents for further development.
Collapse
Affiliation(s)
- Ya Wang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, College of Science, Yunnan Agricultural University, Kunming 650201, China; (Y.W.); (Y.-R.X.); (L.-X.W.); (N.Z.); (Y.-L.W.); (Y.N.); (D.-Y.Z.)
- College of Food Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Xiao-Jing Shen
- Party Committee of Organ, Yunnan Agricultural University, Kunming 650201, China;
| | - Fa-Wu Su
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China;
| | - Yin-Rong Xie
- Key Laboratory of Pu-er Tea Science, Ministry of Education, College of Science, Yunnan Agricultural University, Kunming 650201, China; (Y.W.); (Y.-R.X.); (L.-X.W.); (N.Z.); (Y.-L.W.); (Y.N.); (D.-Y.Z.)
- College of Food Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Li-Xia Wang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, College of Science, Yunnan Agricultural University, Kunming 650201, China; (Y.W.); (Y.-R.X.); (L.-X.W.); (N.Z.); (Y.-L.W.); (Y.N.); (D.-Y.Z.)
- College of Food Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Ning Zhang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, College of Science, Yunnan Agricultural University, Kunming 650201, China; (Y.W.); (Y.-R.X.); (L.-X.W.); (N.Z.); (Y.-L.W.); (Y.N.); (D.-Y.Z.)
- College of Food Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Yi-Long Wu
- Key Laboratory of Pu-er Tea Science, Ministry of Education, College of Science, Yunnan Agricultural University, Kunming 650201, China; (Y.W.); (Y.-R.X.); (L.-X.W.); (N.Z.); (Y.-L.W.); (Y.N.); (D.-Y.Z.)
- College of Food Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Yun Niu
- Key Laboratory of Pu-er Tea Science, Ministry of Education, College of Science, Yunnan Agricultural University, Kunming 650201, China; (Y.W.); (Y.-R.X.); (L.-X.W.); (N.Z.); (Y.-L.W.); (Y.N.); (D.-Y.Z.)
- College of Food Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Dong-Ying Zhang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, College of Science, Yunnan Agricultural University, Kunming 650201, China; (Y.W.); (Y.-R.X.); (L.-X.W.); (N.Z.); (Y.-L.W.); (Y.N.); (D.-Y.Z.)
| | - Cheng-Ting Zi
- Key Laboratory of Pu-er Tea Science, Ministry of Education, College of Science, Yunnan Agricultural University, Kunming 650201, China; (Y.W.); (Y.-R.X.); (L.-X.W.); (N.Z.); (Y.-L.W.); (Y.N.); (D.-Y.Z.)
| | - Xuan-Jun Wang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, College of Science, Yunnan Agricultural University, Kunming 650201, China; (Y.W.); (Y.-R.X.); (L.-X.W.); (N.Z.); (Y.-L.W.); (Y.N.); (D.-Y.Z.)
| | - Jun Sheng
- Key Laboratory of Pu-er Tea Science, Ministry of Education, College of Science, Yunnan Agricultural University, Kunming 650201, China; (Y.W.); (Y.-R.X.); (L.-X.W.); (N.Z.); (Y.-L.W.); (Y.N.); (D.-Y.Z.)
- College of Food Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| |
Collapse
|
2
|
Alejo-Armijo A, Glibota N, Frías MP, Altarejos J, Gálvez A, Salido S, Ortega-Morente E. Synthesis and Evaluation of Antimicrobial and Antibiofilm Properties of A-Type Procyanidin Analogues against Resistant Bacteria in Food. J Agric Food Chem 2018; 66:2151-2158. [PMID: 29464945 DOI: 10.1021/acs.jafc.8b00535] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Natural A-type procyanidins have shown very interesting biological activities, such as their proven antiadherence properties against pathogenic bacteria. In order to find the structural features responsible for their activities, we describe herein the design and synthesis of six A-type procyanidin analogues and the evaluation of their antimicrobial and antibiofilm properties against 12 resistant bacteria, both Gram positive and Gram negative, isolated from organic foods. The natural A-type procyanidin A-2, which had known antiadherence activity, was also tested as a reference compound for the comparative studies. Within the series, analogue 4, which had a NO2 group on ring A, showed the highest antimicrobial activity (MIC of 10 μg/mL) and was one of the best molecules at preventing biofilm formation (up to 40% decreases at 100 μg/mL) and disrupting preformed biofilms (up to 40% reductions at 0.1 μg/mL). Structure-activity relationships are also analyzed.
Collapse
|
3
|
Sarmiento V, Ramirez-Sanchez I, Moreno-Ulloa A, Romero-Perez D, Chávez D, Ortiz M, Najera N, Correa-Basurto J, Villarreal F, Ceballos G. Synthesis of novel (-)-epicatechin derivatives as potential endothelial GPER agonists: Evaluation of biological effects. Bioorg Med Chem Lett 2018; 28:658-663. [PMID: 29395974 PMCID: PMC5817025 DOI: 10.1016/j.bmcl.2018.01.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 01/11/2018] [Accepted: 01/16/2018] [Indexed: 01/20/2023]
Abstract
To potentially identify proteins that interact (i.e. bind) and may contribute to mediate (-)-epicatechin (Epi) responses in endothelial cells we implemented the following strategy: 1) synthesis of novel Epi derivatives amenable to affinity column use, 2) in silico molecular docking studies of the novel derivatives on G protein-coupled estrogen receptor (GPER), 3) biological assessment of the derivatives on NO production, 4) implementation of an immobilized Epi derivative affinity column and, 5) affinity column based isolation of Epi interacting proteins from endothelial cell protein extracts. For these purposes, the Epi phenol and C3 hydroxyl groups were chemically modified with propargyl or mesyl groups. Docking studies of the novel Epi derivatives on GPER conformers at 14 ns and 70 ns demostrated favorable thermodynamic interactions reaching the binding site. Cultures of bovine coronary artery endothelial cells (BCAEC) treated with Epi derivatives stimulated NO production via Ser1179 phosphorylation of eNOS, effects that were attenuated by the use of the GPER blocker, G15. Epi derivative affinity columns yielded multiple proteins from BCAEC. Proteins were electrophoretically separated and inmmunoblotting analysis revealed GPER as an Epi derivative binding protein. Altogether, these results validate the proposed strategy to potentially isolate and identify novel Epi receptors that may account for its biological activity.
Collapse
Affiliation(s)
| | - Israel Ramirez-Sanchez
- Escuela Superior de Medicina del Instituto Politécnico Nacional, Sección de Posgrado, Mexico
| | - Aldo Moreno-Ulloa
- Departamento de Innovación Biomédica, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), BC, Mexico
| | | | - Daniel Chávez
- Centro de Graduados e Investigación en Química del Instituto Tecnológico de Tijuana, Apartado Postal 1166, Tijuana, BC 22510, Mexico
| | - Miguel Ortiz
- Escuela Superior de Medicina del Instituto Politécnico Nacional, Sección de Posgrado, Mexico
| | - Nayelli Najera
- Escuela Superior de Medicina del Instituto Politécnico Nacional, Sección de Posgrado, Mexico
| | - Jose Correa-Basurto
- Escuela Superior de Medicina del Instituto Politécnico Nacional, Sección de Posgrado, Mexico
| | | | - Guillermo Ceballos
- Escuela Superior de Medicina del Instituto Politécnico Nacional, Sección de Posgrado, Mexico.
| |
Collapse
|
4
|
Zhang X, Wang J, Hu JM, Huang YW, Wu XY, Zi CT, Wang XJ, Sheng J. Synthesis and Biological Testing of Novel Glucosylated Epigallocatechin Gallate (EGCG) Derivatives. Molecules 2016; 21:molecules21050620. [PMID: 27187321 PMCID: PMC6274015 DOI: 10.3390/molecules21050620] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 05/02/2016] [Accepted: 05/04/2016] [Indexed: 01/05/2023] Open
Abstract
Epigallocatechin gallate (EGCG) is the most abundant component of green tea catechins and has strong physiological activities. In this study, two novel EGCG glycosides (EGCG-G1 and EGCG-G2) were chemoselectively synthesized by a chemical modification strategy. Each of these EGCG glycosides underwent structure identification, and the structures were assigned as follows: epigallocatechin gallate-4′′-O-β-d-glucopyranoside (EGCG-G1, 2) and epigallocatechin gallate-4′,4′′-O-β-d-gluco-pyranoside (EGCG-G2, 3). The EGCG glycosides were evaluated for their anticancer activity in vitro against two human breast cell lines (MCF-7 and MDA-MB-231) using MTT assays. The inhibition rate of EGCG glycosides (EGCG-G1 and EGCG-G2) is not obvious. The EGCG glycosides are more stable than EGCG in aqueous solutions, but exhibited decreasing antioxidant activity in the DPPH radical-scavenging assay (EGCG > EGCG-G2 > EGCG-G1). Additionally, the EGCG glycosides exhibited increased water solubility: EGCG-G2 and EGCG-G1 were 15 and 31 times as soluble EGCG, respectively. The EGCG glycosides appear to be useful, and further studies regarding their biological activity are in progress.
Collapse
Affiliation(s)
- Xin Zhang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming 650201, China.
- Tea Research Center of Yunnan, Kunming 650201, China.
- Pu-er Tea Academy, Yunnan Agricultural University, Kunming 650201, China.
| | - Jing Wang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming 650201, China.
- Tea Research Center of Yunnan, Kunming 650201, China.
| | - Jiang-Miao Hu
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
| | - Ye-Wei Huang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming 650201, China.
- Tea Research Center of Yunnan, Kunming 650201, China.
| | - Xiao-Yun Wu
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming 650201, China.
- Tea Research Center of Yunnan, Kunming 650201, China.
- Pu-er Tea Academy, Yunnan Agricultural University, Kunming 650201, China.
| | - Cheng-Ting Zi
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming 650201, China.
- Tea Research Center of Yunnan, Kunming 650201, China.
- Pu-er Tea Academy, Yunnan Agricultural University, Kunming 650201, China.
| | - Xuan-Jun Wang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming 650201, China.
- Tea Research Center of Yunnan, Kunming 650201, China.
- Pu-er Tea Academy, Yunnan Agricultural University, Kunming 650201, China.
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Kunming 650201, China.
| | - Jun Sheng
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming 650201, China.
- Tea Research Center of Yunnan, Kunming 650201, China.
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Kunming 650201, China.
| |
Collapse
|
5
|
Chen Z, Yu T, Zhou B, Wei J, Fang Y, Lu J, Guo L, Chen W, Liu ZP, Luo J. Mg(II)-Catechin nanoparticles delivering siRNA targeting EIF5A2 inhibit bladder cancer cell growth in vitro and in vivo. Biomaterials 2016; 81:125-134. [PMID: 26731576 DOI: 10.1016/j.biomaterials.2015.11.022] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 11/09/2015] [Accepted: 11/11/2015] [Indexed: 01/20/2023]
Abstract
Emerging evidence indicates that combination of two or more therapeutic strategies can synergistically enhance antitumor activity in cancer therapy. Here, we established a green method of generating nanocomposite particles that can be fabricated using catechin, a natural anti-cancer compound from green tea, and Mg(2+) in an easy one-step approach at room temperature. We show that Mg(II)-Catechin nanocomposite particles (Mg(II)-Cat NPs) have good biocompatibility and high cellular uptake also can load and effectively deliver small interfering RNA (siRNA) into cells in vitro and to tumor site in vivo. Mg(II)-Cat NPs by themselves had tumor-suppression effects. When complexed with siRNA that targets oncogene eukaryotic translation initiation factor 5A2 (EIF5A2), Mg(II)-Cat/siEIF5A2 complex had further enhanced anti-tumor activity. Mechanistically, we show that Mg(II)-Cat/siEIF5A2 inhibits oncogenic PI3K/Akt signal pathway. More importantly, Mg(II)-Cat/siEIF5A2 had tumor suppression effect in a clinically-relevant rat in-situ bladder cancer model. Our studies demonstrated that combination of Mg(II)-Cat NPs and siRNA is a promising therapeutic modality of combining chemotherapy with gene therapy in order to afford higher therapeutic efficacy and provided a proof of principle for such modality in a pre-clinical setting.
Collapse
Affiliation(s)
- Zhenhua Chen
- Department of Urology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Ting Yu
- Department of Pharmacy, Hainan General Hospital, Haikou, 570311, China
| | - Bangfen Zhou
- Department of Urology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Jinhuan Wei
- Department of Urology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Yong Fang
- Department of Urology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Jun Lu
- Department of Urology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080, China
| | - Ling Guo
- Department of Nephrology, QiLu Hospital of Shandong University, Jinan, 250012, China
| | - Wei Chen
- Department of Urology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080, China.
| | - Zhi-Ping Liu
- Departments of Internal Medicine and Molecular Biology, UT Southwestern Medical Center, Dallas, TX, 75390, USA.
| | - Junhang Luo
- Department of Urology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080, China.
| |
Collapse
|
6
|
Liang K, Ng S, Lee F, Lim J, Chung JE, Lee SS, Kurisawa M. Targeted intracellular protein delivery based on hyaluronic acid-green tea catechin nanogels. Acta Biomater 2016; 33:142-52. [PMID: 26785145 DOI: 10.1016/j.actbio.2016.01.011] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 12/31/2015] [Accepted: 01/12/2016] [Indexed: 12/31/2022]
Abstract
A novel ternary nanogel based on the self-assembly of hyaluronic acid-epigallocatechin gallate conjugates (HA-EGCG), linear polyethylenimine (PEI) and Granzyme B (GzmB) in an aqueous environment was developed for the targeted intracellular delivery of GzmB into cancer cells. Lysozyme-encapsulated HA-EGCG nanogels were first prepared and characterized. HA-EGCG nanogels exhibited smaller particle sizes and a more homogeneous size distribution than the HA counterpart. Fluorescence quenching and lysozyme activity studies revealed that EGCG moieties facilitated protein binding through physical interactions and led to the formation of stable nanogels. When CD44-overexpressing HCT-116 colon cancer cells were treated with GzmB-encapsulated HA-EGCG nanogels in vitro, a significant cytotoxic effect was observed. Caspase assays and intracellular trafficking studies confirmed that cell death was due to apoptosis triggered by the delivery of GzmB to the cytosol of those cells. In comparison, little cytotoxic effect was observed in CD44-deficient cells treated with GzmB-encapsulated HA-EGCG nanogels. This study highlights the potential utility of HA-EGCG as effective intracellular protein carriers for targeted cancer therapy. STATEMENT OF SIGNIFICANCE Intracellularly activated cytotoxic proteins can be used to kill cancer cells but viable carriers for such proteins are lacking. In this work, we developed novel nanogels based on selfassembly of hyaluronic acid (HA)-(-)-epigallocatechin-3-gallate (EGCG) conjugates, linear polyethylenemine (PEI) and the cytotoxic protein Granzyme B (GzmB) for the intracellular delivery of GzmB for cancer therapy. HA was exploited for its ability to target CD44 which are overexpressed in many types of cancer cells, while EGCG, the main component of green tea catechins, was chosen for its ability to bind to proteins. Characterization studies showed that EGCG facilitated protein complexation through physical interactions and led to the formation of stable nanogels. HA-EGCG nanogels were able to achieve CD44 targeted killing of HCT-116 cancer cells by delivering GzmB into the cytosol of these cells. We believe that the applications of the HA-EGCG nanogels can be expanded to the intracellular delivery of other cytotoxic protein drugs for cancer therapy.
Collapse
Affiliation(s)
- Kun Liang
- Institute of Bioengineering & Nanotechnology (IBN), 31 Biopolis Way, The Nanos, #04-01, Singapore 138669, Singapore
| | - Shengyong Ng
- Institute of Bioengineering & Nanotechnology (IBN), 31 Biopolis Way, The Nanos, #04-01, Singapore 138669, Singapore
| | - Fan Lee
- Institute of Bioengineering & Nanotechnology (IBN), 31 Biopolis Way, The Nanos, #04-01, Singapore 138669, Singapore
| | - Jaehong Lim
- Institute of Bioengineering & Nanotechnology (IBN), 31 Biopolis Way, The Nanos, #04-01, Singapore 138669, Singapore
| | - Joo Eun Chung
- Institute of Bioengineering & Nanotechnology (IBN), 31 Biopolis Way, The Nanos, #04-01, Singapore 138669, Singapore
| | - Su Seong Lee
- Institute of Bioengineering & Nanotechnology (IBN), 31 Biopolis Way, The Nanos, #04-01, Singapore 138669, Singapore
| | - Motoichi Kurisawa
- Institute of Bioengineering & Nanotechnology (IBN), 31 Biopolis Way, The Nanos, #04-01, Singapore 138669, Singapore.
| |
Collapse
|
7
|
Blount JW, Redan BW, Ferruzzi MG, Reuhs BL, Cooper BR, Harwood JS, Shulaev V, Pasinetti G, Dixon RA. Synthesis and quantitative analysis of plasma-targeted metabolites of catechin and epicatechin. J Agric Food Chem 2015; 63:2233-40. [PMID: 25671729 DOI: 10.1021/jf505922b] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Grape seed polyphenolic extract (GSPE) rich in the flavan-3-ols (+)-catechin and (-)-epicatechin beneficially modulates Alzheimer's Disease phenotypes in animal models. The parent molecules in the extract are converted to a series of methylated and glucuronidated derivatives. To fully characterize these metabolites and establish a robust quantitative assay of their levels in biological fluids, we have implemented a partial synthetic approach utilizing chemical methylation followed by enzymatic glucuronidation. Liquid chromatography/time-of-flight mass spectrometry (LC-TOF-MS) and nuclear magnetic resonance (NMR) spectroscopy were used to assign unequivocal structures to the compounds. An analytical method using solid-phase extraction and LC-MS/MS in selective reaction monitoring mode (SRM) was validated for their quantitation in plasma. These studies provide a basis for improvements in future work on the bioavailability, metabolism, and mechanism of action of metabolites derived from dietary flavan-3-ols in a range of interventions.
Collapse
Affiliation(s)
- Jack W Blount
- Department of Biological Sciences, University of North Texas , 1155 Union Circle #305220, Denton, Texas 76203-5017, United States
| | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Bhat R, Adam AT, Lee JJ, Deloison G, Rouillé Y, Séron K, Rotella DP. Structure-activity studies of (-)-epigallocatechin gallate derivatives as HCV entry inhibitors. Bioorg Med Chem Lett 2014; 24:4162-5. [PMID: 25103601 DOI: 10.1016/j.bmcl.2014.07.051] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 07/15/2014] [Accepted: 07/17/2014] [Indexed: 11/18/2022]
Abstract
Preventing viral entry into cells is a recognized approach for HIV therapy and has attracted attention for use against the hepatitis C virus (HCV). Recent reports described the activity of (-)-epigallocatechin gallate (EGCG) as an inhibitor of HCV entry with modest potency. EGCG is a polyphenolic natural product with a wide range of biological activity and unfavorable pharmaceutical properties. In an attempt to identify more drug-like EGCG derivatives with improved efficacy as HCV entry inhibitors, we initiated structure-activity investigations using semi-synthetic and synthetic EGCG analogs. The data show that there are multiple regions in the EGCG structure that contribute to activity. The gallate ester portion of the molecule appears to be of particular importance as a 3,4-difluoro analog of EGCG enhanced potency. This derivative and other active compounds were shown not to be cytotoxic in Huh-7 cell culture. These data suggest that more potent, non-cytotoxic EGCG analogs can be prepared in an attempt to identify more drug-like candidates to treat HCV infection by this mechanism.
Collapse
Affiliation(s)
- Rohit Bhat
- Department of Chemistry and Biochemistry, Montclair State University, Montclair, NJ 07043, United States
| | - Amna T Adam
- Department of Chemistry and Biochemistry, Montclair State University, Montclair, NJ 07043, United States
| | - Jungeun Jasmine Lee
- Department of Chemistry and Biochemistry, Montclair State University, Montclair, NJ 07043, United States
| | - Gaspard Deloison
- BioImaging Center Lille-Nord de France, IFR142, Institut Pasteur de Lille, F-59021 Lille, France
| | - Yves Rouillé
- Hepatitis C Laboratory, Center for Infection & Immunity of Lille (CIIL), Université Lille Nord de France, Institut Pasteur de Lille, CNRS-UMR8204, Inserm-U1019, F-59021 Lille, France
| | - Karin Séron
- Hepatitis C Laboratory, Center for Infection & Immunity of Lille (CIIL), Université Lille Nord de France, Institut Pasteur de Lille, CNRS-UMR8204, Inserm-U1019, F-59021 Lille, France.
| | - David P Rotella
- Department of Chemistry and Biochemistry, Montclair State University, Montclair, NJ 07043, United States.
| |
Collapse
|
9
|
Abstract
Lipophilic catechins were synthesized to improve absorption into living bodies and obtain new antioxidants effective in lipid bilayers. The hydroxyl (OH) groups of (+)-catechin was acylated randomly using lauroyl chloride. The mixture was separated by preparative HPLC, and 3-lauroyl-, 3',4'-dilauroyl- and 3,3',4'-trilauroyl-catechins (3-LC, 3',4'-LC, and 3,3',4'-LC) were obtained, their structures being determined by (1)H NMR. Their radical scavenging activity was measured in a ethanol solution using the 1,1-diphenyl-2-picrylhydrazyl radical, and was compared with that of (+)-catechin. The activity of 3-LC was almost same as that of (+)-catechin, but those of 3',4'-LC and 3,3',4'-LC were small, showing that the blocking of phenolic OH groups in the B ring lowered the activity. The scavenging activity on lipophilic radicals in a liposome system was also measured, and the activities were in the order of 3-LC > 3',4'-LC = (+)-catechin. These results suggested that radical scavenging activity in the lipid membrane depended not only on the number and the relative positions of phenolic OH groups of catechins but also on affinity to the membrane.
Collapse
Affiliation(s)
- Guangzhi Jin
- Institute for Environmental Sciences, University of Shizuoka, Yada, Japan
| | | |
Collapse
|
10
|
Zhao C, Liu S, Li C, Yang L, Zu Y. In vitro evaluation of the antiviral activity of the synthetic epigallocatechin gallate analog-epigallocatechin gallate (EGCG) palmitate against porcine reproductive and respiratory syndrome virus. Viruses 2014; 6:938-50. [PMID: 24566281 PMCID: PMC3939490 DOI: 10.3390/v6020938] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 01/13/2014] [Accepted: 02/12/2014] [Indexed: 11/16/2022] Open
Abstract
In this study, epigallocatechin gallate (EGCG) palmitate was synthesized and its anti-porcine reproductive and respiratory syndrome virus (PRRSV) activity was studied. Specifically, EGCG palmitate was evaluated for its ability to inhibit PRRSV infection in MARC-145 cells when administered as pre-, post-, or co-treatment. EGCG and ribavirin were used as controls. The results showed that a 50% cytotoxic concentration (CC50) of EGCG, EGCG palmitate, and ribavirin was achieved at 2,359.71, 431.42, and 94.06 μM, respectively. All three drugs inhibited PRRSV in a dose-dependent manner regardless of the treatment protocol. EGCG palmitate exhibited higher cytotoxicity than EGCG, but lower cytotoxicity than ribavirin. EGCG palmitate anti-PRRSV activity was significantly higher than that of EGCG and ribavirin, both as pre-treatment and post-treatment. Under the former conditions and a tissue culture infectious dose of 10 and 100, the selectivity index (SI) of EGCG palmitate in the inhibition of PRRSV was 3.8 and 2.9 times higher than that of ribavirin when administered as a pre-treatment, while the SI of EGCG palmitate in the inhibition of PRRSV was 3.0 and 1.9 times higher than ribavirin when administered as a post-treatment. Therefore, EGCG palmitate is potentially effective as an anti-PRRSV agent and thus of interest to the pharmaceutical industry.
Collapse
Affiliation(s)
- Chunjian Zhao
- State Engineering Laboratory for Bio-Resource Eco-Utilization, Northeast Forestry University, Harbin 150040, China.
| | - Shuaihua Liu
- State Engineering Laboratory for Bio-Resource Eco-Utilization, Northeast Forestry University, Harbin 150040, China.
| | - Chunying Li
- State Engineering Laboratory for Bio-Resource Eco-Utilization, Northeast Forestry University, Harbin 150040, China.
| | - Lei Yang
- State Engineering Laboratory for Bio-Resource Eco-Utilization, Northeast Forestry University, Harbin 150040, China.
| | - Yuangang Zu
- State Engineering Laboratory for Bio-Resource Eco-Utilization, Northeast Forestry University, Harbin 150040, China.
| |
Collapse
|
11
|
Okamoto S, Ishihara S, Okamoto T, Doi S, Harui K, Higashino Y, Kawasaki T, Nakajima N, Saito A. Inhibitory activity of synthesized acetylated Procyanidin B1 analogs against HeLa S3 cells proliferation. Molecules 2014; 19:1775-85. [PMID: 24500007 PMCID: PMC6271516 DOI: 10.3390/molecules19021775] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 01/22/2014] [Accepted: 01/28/2014] [Indexed: 11/17/2022] Open
Abstract
Proanthocyanidins, also known as condensed tannins and/or oligomeric flavonoids, occur in many edible plants and have various interesting biological activities. Previously, we reported a synthetic method for the preparation of various procyanidins in pure form and described their biological activities. Here, we describe the synthesis of procyanidin B1 acetylated analogs and discuss their inhibition activities against HeLa S3 cell proliferation. Surprisingly, the lower-unit acetylated procyanidin B1 strongly inhibited the proliferation of HeLa S3 cells. This molecule showed much stronger inhibitory activity than did epigallocatechin-3-O-gallate (EGCG), green tea polyphenol, and dimeric compounds that included EGCG as a unit. This result suggests that the phenolic hydroxyl groups of the upper-units in flavan-3-ols are important for their inhibitory activity against cancer cell proliferation and that a hydrophobic lower unit dimer enhances this activity.
Collapse
Affiliation(s)
- Syuhei Okamoto
- Graduate School of Engineering, Osaka Electro-communication University (OECU), 18-8 Hatsu-cho, Neyagawa-shi, Osaka 572-8530, Japan.
| | - Sayaka Ishihara
- Graduate School of Engineering, Osaka Electro-communication University (OECU), 18-8 Hatsu-cho, Neyagawa-shi, Osaka 572-8530, Japan.
| | - Taisuke Okamoto
- Graduate School of Engineering, Osaka Electro-communication University (OECU), 18-8 Hatsu-cho, Neyagawa-shi, Osaka 572-8530, Japan.
| | - Syoma Doi
- Graduate School of Engineering, Osaka Electro-communication University (OECU), 18-8 Hatsu-cho, Neyagawa-shi, Osaka 572-8530, Japan.
| | - Kota Harui
- Graduate School of Engineering, Osaka Electro-communication University (OECU), 18-8 Hatsu-cho, Neyagawa-shi, Osaka 572-8530, Japan.
| | - Yusuke Higashino
- Graduate School of Engineering, Osaka Electro-communication University (OECU), 18-8 Hatsu-cho, Neyagawa-shi, Osaka 572-8530, Japan.
| | - Takashi Kawasaki
- Department of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan.
| | - Noriyuki Nakajima
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan.
| | - Akiko Saito
- Graduate School of Engineering, Osaka Electro-communication University (OECU), 18-8 Hatsu-cho, Neyagawa-shi, Osaka 572-8530, Japan.
| |
Collapse
|
12
|
Sáez-Ayala M, Fernández-Pérez MP, Chazarra S, Mchedlishvili N, Tárraga-Tomás A, Rodríguez-López JN. Factors influencing the antifolate activity of synthetic tea-derived catechins. Molecules 2013; 18:8319-41. [PMID: 23863773 PMCID: PMC6270263 DOI: 10.3390/molecules18078319] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 07/05/2013] [Accepted: 07/12/2013] [Indexed: 11/16/2022] Open
Abstract
Novel tea catechin derivatives have been synthesized, and a structure-activity study, related to the capacity of these and other polyphenols to bind dihydrofolate reductase (DHFR), has been performed. The data showed an effective binding between all molecules and the free enzyme, and the dissociation constants of the synthetic compounds and of the natural analogues were on the same order. Polyphenols with a catechin configuration were better DHFR inhibitors than those with an epicatechin configuration. Antiproliferative activity was also studied in cultured tumour cells, and the data showed that the activity of the novel derivatives was higher in catechin isomers. Derivatives with a hydroxyl group para on the ester-bonded gallate moiety presented a high in vitro binding to DHFR, but exhibited transport problems in cell culture due to ionization at physiologic pHs. The impact of the binding of catechins to serum albumin on their biological activity was also evaluated. The information provided in this study could be important for the design of novel medicinal active compounds derived from tea catechins. The data suggest that changes in their structure to avoid serum albumin interactions and to facilitate plasmatic membrane transport are essential for the intracellular functions of catechins.
Collapse
Affiliation(s)
- Magalí Sáez-Ayala
- Department of Biochemistry and Molecular Biology A, School of Biology, Regional Campus of International Excellence “Campus Mare Nostrum”, University of Murcia, 30100, Murcia, Spain; E-Mails: (M.S.-A.); (M.P.F.-P.); (S.C.)
| | - María Piedad Fernández-Pérez
- Department of Biochemistry and Molecular Biology A, School of Biology, Regional Campus of International Excellence “Campus Mare Nostrum”, University of Murcia, 30100, Murcia, Spain; E-Mails: (M.S.-A.); (M.P.F.-P.); (S.C.)
| | - Soledad Chazarra
- Department of Biochemistry and Molecular Biology A, School of Biology, Regional Campus of International Excellence “Campus Mare Nostrum”, University of Murcia, 30100, Murcia, Spain; E-Mails: (M.S.-A.); (M.P.F.-P.); (S.C.)
| | - Nani Mchedlishvili
- Durmishidze Institute of Biochemistry and Biotechnology of Agrarian University of Georgia, 0131, Tbilisi, Georgia; E-Mail:
| | - Alberto Tárraga-Tomás
- Department of Organic Chemistry, Faculty of Chemistry, Regional Campus of International Excellence “Campus Mare Nostrum”, University of Murcia, 30100, Murcia, Spain; E-Mail:
| | - José Neptuno Rodríguez-López
- Department of Biochemistry and Molecular Biology A, School of Biology, Regional Campus of International Excellence “Campus Mare Nostrum”, University of Murcia, 30100, Murcia, Spain; E-Mails: (M.S.-A.); (M.P.F.-P.); (S.C.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +34-868-888-284; Fax: +34-868-884-782
| |
Collapse
|
13
|
Jeon SY, Oh S, Kim E, Imm JY. α-Glucosidase inhibiton and antiglycation activity of laccase-catalyzed catechin polymers. J Agric Food Chem 2013; 61:4577-4584. [PMID: 23651430 DOI: 10.1021/jf400791r] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Catechin polymers were produced by laccase (12 U/mL) in a mixture of sodium acetate buffer (1% (+)-catechin, 100 mM, pH 5) and methanol (buffer:methanol = 95:5, v/v). The freeze-dried catechin polymers were recovered from the precipitate after dialysis followed by centrifugation. Catechin polymers extracted with 20% ethanol had potent inhibitory activity against α-glucosidase with an IC50 value of 4 μg/mL, and they were present as a mixture of dimers, trimers, and tetramers. The antihyperglycemic effect of the catechin polymers was confirmed by an oral maltose tolerance test. The catechin polymers also had significantly improved antiglycation and superoxide dismutase-like activities compared to those of (+)-catechin. Since formation of advanced glycation end products and oxidative stress are accelerated in hyperglycemic conditions, we suggest that enzymatic production of catechin polymers could have a potential protective effect in type 2 diabetes, diabetic complications, and other free radical related diseases.
Collapse
Affiliation(s)
- So-Youn Jeon
- Department of Foods and Nutrition, Kookmin University, Seoul, Korea
| | | | | | | |
Collapse
|
14
|
Zhang M, Jagdmann GE, Van Zandt M, Sheeler R, Beckett P, Schroeter H. Chemical synthesis and characterization of epicatechin glucuronides and sulfates: bioanalytical standards for epicatechin metabolite identification. J Nat Prod 2013; 76:157-69. [PMID: 23356946 DOI: 10.1021/np300568m] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The monoglucuronides and sulfates of epicatechin, 3'-O-methylepicatechin, and 4'-O-methylepicatechin, respectively, were synthesized as authentic bioanalytical standards. Reversed-phase HPLC methods capable of baseline separation of the glucuronides and sulfates have been developed. Both the epicatechin glucuronides and sulfates were stable in the solid state when stored under ambient conditions and in aqueous solution when stored refrigerated. These results should prove invaluable to the research community as analytical standards as well as in future studies of the biological and pharmacological effects of epicatechin in humans.
Collapse
Affiliation(s)
- Mingbao Zhang
- Institutes for Pharmaceutical Discovery, 23 Business Park Drive, Branford, Connecticut 06405, United States
| | | | | | | | | | | |
Collapse
|
15
|
Abstract
Results emanating from the synthesis of proanthocyanidins played a crucial role in defining the constitution, regiochemistry, and absolute configuration of this complex but fascinating group of plant secondary metabolites. The initial efforts, commencing in 1966, were focused on structure elucidation of, especially, the procyanidins, profisetinidins, and prorobinetinidins. However, over the past 12 years the emphasis has shifted to the synthesis of the bioactive procyanidins and some of their derivatives at a scale that would permit assessment of their pharmacological properties. With a few exceptions, the vast majority of these synthetic protocols involve the formation of the interflavanyl bond by acid/Lewis acid activation at C-4 of a flavan-3,4-diol or its equivalent, and subsequent trapping of the incipient C-4 carbocation by the nucleophilic centers of a flavan-3-ol (catechin). This review represents the first comprehensive chronicle depicting the development of the subject of proanthocyanidin synthesis.
Collapse
Affiliation(s)
- Daneel Ferreira
- Department of Pharmacognosy, School of Pharmacy, University of Mississippi, University, MS 38677, USA.
| | | |
Collapse
|
16
|
Nave F, Teixeira N, Mateus N, de Freitas V. Hemisynthesis and structural characterization of flavanol-(4,8)-vitisins by mass spectrometry. Rapid Commun Mass Spectrom 2010; 24:1964-1970. [PMID: 20552703 DOI: 10.1002/rcm.4599] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Vitisins constitute the major group of pyranoanthocyanins naturally occurring in red wines. Regarding their chemical structure, only carboxypyranoanthocyanins have been detected and quantified in red wines, but no vitisin with substitutions in the carbons of the A ring has been identified. However, considering the chemical reactions that take place in red wine, the existence of flavan-3-ol-(4,6/8)-vitisins is expected. This paper reports for the first time the structural identification of catechin-vitisin A and catechin-vitisin B based on their mass data and fragmentation patterns. This work also provides some chromatographic and visible spectroscopic features of these pigments and documents the existence of both in red table wines. Moreover, it is also proposed that Cat-Vit A pigments arise from the cycloaddition of pyruvic acid to an anthocyanin moiety of a flavanol-anthocyanin adduct rather than by direct nucleophilic attack of a vitisin A on the carbocation C(4) of catechin.
Collapse
Affiliation(s)
- Frederico Nave
- Centro de Investigação em Química, Departamento de Química, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal
| | | | | | | |
Collapse
|
17
|
Huo C, Yang H, Cui QC, Dou QP, Chan TH. Proteasome inhibition in human breast cancer cells with high catechol-O-methyltransferase activity by green tea polyphenol EGCG analogs. Bioorg Med Chem 2010; 18:1252-8. [PMID: 20045338 PMCID: PMC2819655 DOI: 10.1016/j.bmc.2009.12.034] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2009] [Revised: 12/08/2009] [Accepted: 12/10/2009] [Indexed: 10/20/2022]
Abstract
A pro-drug 8 of a synthetic analog 7 is more active in its antiproliferative activity against human breast cancer MDA-MB-231 cells possessing high catechol-O-methyltransferase (COMT) activity than the pro-drugs of EGCG and the analog 5. The higher activity of 8 is attributed to it not being a substrate of COMT.
Collapse
Affiliation(s)
- Congde Huo
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | | | | | | | | |
Collapse
|
18
|
Cruz L, Brás NF, Teixeira N, Fernandes A, Mateus N, Ramos MJ, Rodríguez-Borges J, de Freitas V. Synthesis and structural characterization of two diasteroisomers of vinylcatechin dimers. J Agric Food Chem 2009; 57:10341-10348. [PMID: 19817383 DOI: 10.1021/jf901608n] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
8-Vinylflavan-3-ols are described in the literature as the intermediate compounds involved in the formation mechanism of pyranoanthocyanins in wines or in model-like solutions. 8-Vinyl-(+)-catechin has shown to be very unstable in solution and revealed a high reactivity with itself, undergoing an unusual acid-catalyzed dimerization in model wine solution involving the formation of a new dihydropyran ring. Two diasteroisomers, (9S,11R)- and (9R,11S)-vinylcatechin dimers, were obtained, and their structures were characterized by mass spectrometry (MS) and nuclear magnetic resonance (NMR). These compounds were also found to occur in reactions between (+)-catechin and acetaldehyde. The identification of different conformations of both isomers was achieved by computational methods. The enthalpy values calculated suggest that isomer (9S,11R) is more stable and its formation is thermodynamically favored when compared to isomer (9R,11S).
Collapse
Affiliation(s)
- Luís Cruz
- Centro de Investigacao em Quimica, Departamento de Química, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto, Portugal
| | | | | | | | | | | | | | | |
Collapse
|
19
|
Bhujbal NN, Bande OP, Dhavale DD. Catechuic acid and ethyl 2,4,5-trihydroxybenzoate from D-glucose. Carbohydr Res 2009; 344:734-8. [PMID: 19268918 DOI: 10.1016/j.carres.2009.02.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2009] [Revised: 02/02/2009] [Accepted: 02/03/2009] [Indexed: 11/17/2022]
Abstract
Synthesis of catechuic acid (1) and ethyl 2,4,5-trihydroxybenzoate (2) from D-glucose-derived beta-ketoester is described. The polyhydroxylated beta-ketoester obtained from the hydrolysis of sugar beta-ketoester 3 was subjected to an aldol-type condensation to get 4 that on enolization, dehydration, and hydrogenation afforded ethyl 2,4,5-trihydroxybenzoate (2). On the other hand, hydrogenation of aldol product 4 afforded polyhydroxylated keto-carbasugar 6, which on mild acid treatment and ester hydrolysis in basic media led to catechuic acid 1. Intermediate 4 is co-related to 3-dehydroshikimic acid, a biochemical intermediate from D-glucose in the synthesis of pro-catechuic acid.
Collapse
Affiliation(s)
- Namdeo N Bhujbal
- Garware Research Centre, Department of Chemistry, University of Pune, Pune 411007, India
| | | | | |
Collapse
|
20
|
González-Manzano S, González-Paramás A, Santos-Buelga C, Dueñas M. Preparation and characterization of catechin sulfates, glucuronides, and methylethers with metabolic interest. J Agric Food Chem 2009; 57:1231-8. [PMID: 19182929 DOI: 10.1021/jf803140h] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Catechins are major polyphenols in many plant foods that have been related to health promotion. In the human organism they are largely metabolized to different conjugates (sulfates, glucuronides, and methylethers), which are further found in plasma and would contribute to the biological effects associated with the intake of the parent compounds. Circulating metabolites are likely to possess biological properties different from those of the original compounds, and therefore, it is important to evaluate their activity, for which sufficient amounts of them are required that cannot be obtained by isolation from biological fluids. This paper describes the preparation of the methyl, sulfate, and glucuronide derivatives of catechins using different chemical syntheses and their characterization by HPLC-DAD-ESI/MS. MS2 fragmentation of the compounds was also described that allowed the determination of the location of the different substituents on the catechin aglycones. The procedures optimized allowed the preparation of (epi)catechin sulfates, glucuronides, and methylethers conjugated at positions 3' and 4', as well as the sulfates at positions 5 and 7 with satisfactory yields for their further isolation by semipreparative-HPLC in view of their use in in vitro/ex vivo assays.
Collapse
Affiliation(s)
- Susana González-Manzano
- Unidad de Nutrición y Bromatología, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno, E-37007, Salamanca, Spain
| | | | | | | |
Collapse
|
21
|
Cruz L, Teixeira N, Silva AMS, Mateus N, Borges J, de Freitas V. Role of vinylcatechin in the formation of pyranomalvidin-3-glucoside-+-catechin. J Agric Food Chem 2008; 56:10980-10987. [PMID: 18959409 DOI: 10.1021/jf8021496] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Reactions between malvidin-3-glucoside (mv3glc) and 8-vinylcatechin were carried out to synthesize pyranomv3glc-(+)-catechin pigment and to study the formation of intermediates. A rapid decrease of mv3glc content concomitant with the formation of more complex structures such as mv3glc-vinylcatechin [precursor of pyranomv3glc-(+)-catechin pigment] and mv3glc-divinylcatechin was observed. On the other hand, 8-vinylcatechin undergoes acid-catalyzed dimerization in model wine solution, giving rise to 8-vinylcatechin dimers. These compounds were also found in the reaction between mv3glc and (+)-catechin mediated by acetaldehyde, which provides evidence for the formation of 8-vinylcatechin and its involvement in the formation of pyranoanthocyanins in aged red wines.
Collapse
Affiliation(s)
- Luis Cruz
- Departamento de Quimica, Faculdade de Ciencias, Centro de Investigacao em Quimica, Universidade do Porto, Porto, Portugal
| | | | | | | | | | | |
Collapse
|
22
|
Abstract
A semisynthetic approach for the strategic formation of various procyanidins has been developed. Procyanidin-rich grape seed extracts were reacted with flavan-3-ols under acid catalysis. The reaction enables the formation of dimeric procyanidins and the elimination of higher oligomeric and polymeric procyanidins through degradation. An easy and fast method for the isolation of large amounts of procyanidins after semisynthetic formation by high-speed countercurrent chromatography is presented. Dimeric procyanidins (B1, B2, B3, B4, B5, and B7) were obtained and isolated. Furthermore, galloylated dimeric procyanidins [(-)-epicatechin-3- O-gallate-4beta-->8-(+)-catechin, (-)-epicatechin-3- O-gallate-4beta-->8-(-)-epicatechin, (-)-epicatechin-3- O-gallate-4beta-->6-(-)-epicatechin, and (-)-epicatechin-4beta-->8-(-)-epicatechin-3- O-gallate], as well as trimeric procyanidins [C1, (-)-epicatechin-4beta-->6-(-)-epicatechin-4beta-->8-(-)-epicatechin, and (-)-epicatechin-4beta-->6-(-)-epicatechin-4beta-->6-(+)-catechin] were obtained and isolated as side products. This approach also afforded gambiriins A1 and A2, which were all isolated and unambiguously identified, and the novel 3-(2,4,6-trihydroxyphenyl)-1-(3,4-dihydroxyphenyl)-propan-2-ol-1beta-->8-(-)-epicatechin (gambiriin A4).
Collapse
Affiliation(s)
- Nils Köhler
- Institute of Food Chemistry, University of Braunschweig-Institute of Technology, Schleinitzstrasse 20, 38106 Braunschweig, Germany
| | | | | |
Collapse
|
23
|
Dias K, Nikolaou S, De Giovani WF. Synthesis and spectral investigation of Al(III) catechin/beta-cyclodextrin and Al(III) quercetin/beta-cyclodextrin inclusion compounds. Spectrochim Acta A Mol Biomol Spectrosc 2008; 70:154-161. [PMID: 18054838 DOI: 10.1016/j.saa.2007.07.022] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2007] [Accepted: 07/19/2007] [Indexed: 05/25/2023]
Abstract
Al-catechin/beta-cyclodextrin and Al-quercetin/beta-cyclodextrin (beta-CD) inclusion compounds were synthesized and characterized by IR, UV-vis, 1H and 13C NMR and TG and DTA analyses. Because quercetin is sparingly soluble in water, the stability constants of the Al-quercetin/beta-CD and Al-catechin/beta-CD compounds were determined by phase solubility studies. The AL-type diagrams indicated the formation of 1:1 inclusion compounds and allowed calculation of the stability constants. The thermodynamic parameters were obtained from the dependence of the stability constants on temperature and results indicated that the formation of the inclusion compounds is an enthalpically driven process. The thermal decomposition of the solid Al-quercetin/beta-CD and Al-catechin/beta-CD inclusion compounds took place at different stages, compared with the respective precursors, proving that an inclusion complexation process really occurred.
Collapse
Affiliation(s)
- Karina Dias
- Departamento de Química, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirão Preto, SP, Brazil
| | | | | |
Collapse
|
24
|
Song JM, Park KD, Lee KH, Byun YH, Park JH, Kim SH, Kim JH, Seong BL. Biological evaluation of anti-influenza viral activity of semi-synthetic catechin derivatives. Antiviral Res 2007; 76:178-85. [PMID: 17709148 DOI: 10.1016/j.antiviral.2007.07.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Revised: 07/03/2007] [Accepted: 07/05/2007] [Indexed: 12/01/2022]
Abstract
Catechin derivatives with different alkyl chain length and aromatic ring substitutions at the 3-hydroxyl group were synthesized from epigallocatechin (EGC) and (+)-catechin (C) and their anti-influenza viral activity were evaluated in vitro and in ovo. Pronounced antiviral activity was observed for derivatives carrying moderate chain length (7-9 carbons) as compared to those with aromatic rings, whereas the 5'-hydroxyl group of the trihydroxy benzyl moiety did not significantly contribute to antiviral activity. The derivatives exerted inhibitory effects for all six influenza subtypes tested including three major types of currently circulating human influenza viruses (A/H1N1, A/H3N2 and B type), H2N2 and H9N2 avian influenza virus. The compounds strongly inhibited adsorption of the viruses on red blood cell (RBC). They also restricted the growth of avian influenza virus in ovo with minimum inhibition concentration (MIC) of 5-10 microM far exceeding the neuraminidase (NA) inhibitor oseltamivir or M2 proton channel inhibitor amantadine. The antiviral activity appears to be mediated by interaction with hemagglutinin (HA)/viral membrane rendering HA less fusogenic at the initial stage of infection. The broad spectrum activity against various subtypes of influenza viruses may complement the limitations of current antivirals and contribute for managing potentially emerging influenza pandemic. The structure-activity data of catechin derivatives may usefully guideline future research endeavors for applying green tea catechins as alternative anti-viral agents.
Collapse
Affiliation(s)
- Jae Min Song
- Department of Biotechnology, College of Engineering, Yonsei University, Seoul, South Korea
| | | | | | | | | | | | | | | |
Collapse
|
25
|
Affiliation(s)
- Hiroshi Tanaka
- Department of Applied Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8552, Japan
| | | | | | | | | |
Collapse
|
26
|
Es-Safi NE, Ghidouche S, Ducrot PH. Flavonoids: hemisynthesis, reactivity, characterization and free radical scavenging activity. Molecules 2007; 12:2228-58. [PMID: 17962740 PMCID: PMC6149145 DOI: 10.3390/12092228] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2007] [Revised: 09/17/2007] [Accepted: 09/18/2007] [Indexed: 11/16/2022] Open
Abstract
Phenolic compounds form one of the main classes of secondary metabolites. They display a large range of structures and they are responsible for the major organoleptic characteristics of plant-derived-foods and beverages, particularly color and taste properties and they also contribute to the nutritional qualities of fruits and vegetables. Phenolic compounds are also highly unstable compounds which undergo numerous enzymatic and chemical reactions during postharvest food storage and processing thus adding to the complexity of plant polyphenol composition. Among these compounds flavonoids constitute one of the most ubiquitous groups of all plant phenolics. Owing to their importance in food organoleptic properties and in human health, a better understanding of their structures, their reactivity and chemical properties in addition to the mechanisms generating them appears essential to predict and control food quality. The purpose of this work is an overview of our findings concerning the hemisynthesis, the reactivity and the enzymatic oxidation of some flavonoids and shed light on the mechanisms involved in some of these processes and the structures of the resulting products. The free radical scavenging activity of some of the synthesized compounds is also presented and a structure-activity relationship is discussed. The first part of this review concerns the synthesis and structural characterization of modified monomeric flavanols. The use of these compounds as precursor for the preparation of natural and modified dimeric procyanidin derivatives was then explored through different coupling reactions. The full characterization of the synthesized compounds was achieved by concerted use of NMR and ESI-MS techniques. The free radical scavenging activity of some of the synthesized compounds was investigated. The second part of this review concerns the enzymatic oxidation of several flavonols by Trametes versicolor laccase. Most of the major oxidation products have been isolated as pure compounds and their structures unambiguously established through spectroscopic methods. Correlation between the structure of the oxidation product and the substitution pattern of the starting materials allows mechanistic features of this transformation to be elucidated.
Collapse
Affiliation(s)
- Nour-Eddine Es-Safi
- Unité de Phytopharmacie et Médiateurs Chimiques, INRA, Route de Saint-Cyr, 78026 Versailles Cedex, France; E-mails: (Guidouche); (Ducrot)
- Laboratoire de Chimie Organique et d’Etudes Physico-Chimiques, Pôle de Compétences Pharmacochimie. Ecole Normale Supérieure, B.P 5118 Takaddoum Rabat, Morocco
| | - Souhila Ghidouche
- Unité de Phytopharmacie et Médiateurs Chimiques, INRA, Route de Saint-Cyr, 78026 Versailles Cedex, France; E-mails: (Guidouche); (Ducrot)
| | - Paul Henri Ducrot
- Unité de Phytopharmacie et Médiateurs Chimiques, INRA, Route de Saint-Cyr, 78026 Versailles Cedex, France; E-mails: (Guidouche); (Ducrot)
| |
Collapse
|
27
|
Hyun EK, Park HY, Kim HJ, Lee JK, Kim D, Oh DK. Production of epigallocatechin gallate 7-O-alpha-D-glucopyranoside (EGCG-G1) using the glucosyltransferase from Leuconostoc mesenteroides. Biotechnol Prog 2007; 23:1082-6. [PMID: 17683120 DOI: 10.1021/bp0700657] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Epigallocatechin gallate 7-O-alpha-D-glucopyranoside (EGCG-G1), as a novel compound with a higher water solubility and stability and similar antioxidant effect when compared with epigallocatechin gallate (EGCG), was produced from sucrose as a glucose donor and EGCG as a glucose acceptor by a glucosyltransferase from Leuconostoc mesenteroides. The pH and temperature for maximum EGCG-G1 production by the glucosyltransferase were 5.0 and 25 degrees C, respectively. The enzyme and substrates concentrations to produce maximum EGCG-G1 were 3.78 units/mL, 25 mM sucrose, and 1.5 mM EGCG, respectively. Under these conditions, the glucosyltransferase produced 1.0 mM EGCG-G1 from 1.5 mM EGCG at a reaction time of 180 min, corresponding to formation of 67% product on a mole basis.
Collapse
Affiliation(s)
- Eun-Kyung Hyun
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 143-701, Republic of Korea
| | | | | | | | | | | |
Collapse
|
28
|
Khrizman A, Moulthrop JS, Little S, Wharton H, Yardley V, Moyna G. Synthesis and in vitro protozoocidal activity of diazabicyclic benzotropolone derivatives. Bioorg Med Chem Lett 2007; 17:4183-6. [PMID: 17532634 DOI: 10.1016/j.bmcl.2007.05.044] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2007] [Revised: 05/11/2007] [Accepted: 05/14/2007] [Indexed: 11/17/2022]
Abstract
We describe the synthesis and protozoocidal evaluation of a series of diazabicycles based on benzotropolone ethers. Several of the compounds, which can be obtained through a high-yielding hetero Diels-Alder reaction using simple and readily available starting materials, have in vitro activities against Trypanosoma cruzi and Leishmania donovani that are comparable to, and in some cases better than, those of currently used chemotherapies.
Collapse
Affiliation(s)
- Alexander Khrizman
- Department of Chemistry & Biochemistry, University of the Sciences in Philadelphia, 600 South 43rd Street, Philadelphia, PA 19104-4495, USA
| | | | | | | | | | | |
Collapse
|
29
|
Abstract
Flavonoids, one of the most numerous and best studied groups of plant polyphenols, are well known to exhibit various biological and pharmacological effects. Functional artificial polymeric flavonoids, flavonoid polymers and amine containing polymer-flavonoid conjugates have been developed. The acid-catalyzed polymerization of catechin and aldehydes proceeds regioselectively to produce catechin-aldehyde polycondensates. Peroxidases and laccases catalyze the oxidative coupling of flavonoids and oxidative conjugation with polyamines. The resulting polymers show much higher antioxidant activities than the flavonoid monomers. In addition, these polymeric flavonoids efficiently inhibit disease related enzymes, such as xanthine oxidase, collagenase, elastase, hyaluronidase and tyrosinase. Based on these results, the molecular design for amplification of the biological and pharmacological properties of flavonoids is proposed.
Collapse
Affiliation(s)
- Hiroshi Uyama
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan.
| |
Collapse
|
30
|
Hayes CJ, Whittaker BP, Watson SA, Grabowska AM. Synthesis and Preliminary Anticancer Activity Studies of C4 and C8-Modified Derivatives of Catechin Gallate (CG) and Epicatechin Gallate (ECG). J Org Chem 2006; 71:9701-12. [PMID: 17168588 DOI: 10.1021/jo061740e] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have developed an improved and reliable method for stereoselective functionalization at C4 of naturally occurring (+)-catechin. Our method utilizes DDQ oxidation followed by trapping of the quinonemethide intermediate with allyl alcohol. The quinonemethide intermediate can be regenerated from the allyl ether by exposure to boron trifluoride diethyl etherate. This reactive intermediate can be trapped with a wide range of external nucleophiles. NBS bromination, lithium halogen exchange, and alkylation gave access to C8-allyl derivatives of (+)-catechin, and this allyl group was used in a series of cross-metathesis experiments to prepare novel dimeric catechin-derived products. Gallate ester derivatives of the novel C4- and C8-substituted catechins were prepared, and these materials were screened for potential anticancer activity in a range of human cancer cell lines. From these preliminary cytotoxicity assays (MTT) we found that C8-propyl-catechin gallate was more active (IC50 = 31 microM) than catechin gallate (CG, IC50 = 53 microM) or epicatechin gallate (ECG, IC50 = 76 microM) against the colorectal adenocarcinoma cell line HCT116. Differential sensitivity in pancreas (Pan1), bladder (RT112), stomach (MGLVA1), liver (HepG2), and fibroblasts (46Br.1G1) cell lines was also observed.
Collapse
Affiliation(s)
- Christopher J Hayes
- School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | | | | | | |
Collapse
|
31
|
Lambert JD, Sang S, Hong J, Kwon SJ, Lee MJ, Ho CT, Yang CS. Peracetylation as a means of enhancing in vitro bioactivity and bioavailability of epigallocatechin-3-gallate. Drug Metab Dispos 2006; 34:2111-6. [PMID: 16997910 DOI: 10.1124/dmd.106.011460] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
(-)-Epigallocatechin-3-gallate (EGCG) is the widely studied catechin in green tea (Camellia sinensis). Previously, we have reported the low bioavailability of EGCG in rats and mice. As a means of improving the bioavailability of EGCG, we have prepared a peracetylated EGCG derivative (AcEGCG) and herein report its growth inhibitory activity and cellular uptake in vitro, as well as bioavailability in mice. AcEGCG exhibited enhanced growth inhibitory activity relative to EGCG in both KYSE150 human esophageal (IC50 = 10 versus 20 microM) and HCT116 human colon cancer cells (IC50 = 32 versus 45 microM). AcEGCG was rapidly converted to EGCG by HCT116 cells, and treatment of cells with AcEGCG resulted in a 2.8- to 30-fold greater intracellular concentration of EGCG as compared with treatment with EGCG. AcEGCG was also more potent than EGCG at inhibiting nitric oxide production (4.4-fold) and arachidonic acid release (2.0-fold) from lipopolysaccharide-stimulated RAW264.7 murine macrophages. Intragastric administration of AcEGCG to CF-1 mice resulted in higher bioavailability compared with administration of equimolar doses of EGCG. The plasma area under the curve from 0 to infinity (AUC0-->infinity) of total EGCG was 465.0 and 194.6 [(microg/ml) . min] from the administration of AcEGCG and EGCG, respectively. The t1/2 of EGCG was also increased following administration of AcEGCG compared with EGCG (441.0 versus 200.3 min). The AUC0-->infinity and t1/2 were also increased in small intestinal (2.8- and 4.3-fold, respectively) and colonic tissues (2.4- and 6.0-fold, respectively). These data suggest that acetylation represents a means of increasing the biological potency in vitro, increasing the bioavailability of EGCG in vivo, and may improve cancer-preventive activity.
Collapse
Affiliation(s)
- Joshua D Lambert
- Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | | | | | | | | | | | | |
Collapse
|
32
|
Hakamata W, Nakanishi I, Masuda Y, Shimizu T, Higuchi H, Nakamura Y, Saito S, Urano S, Oku T, Ozawa T, Ikota N, Miyata N, Okuda H, Fukuhara K. Planar Catechin Analogues with Alkyl Side Chains: A Potent Antioxidant and an α-Glucosidase Inhibitor. J Am Chem Soc 2006; 128:6524-5. [PMID: 16704229 DOI: 10.1021/ja057763c] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Planar catechin analogues having various alkyl side chain lengths were synthesized, and their remarkable antioxidative abilities and alpha-glucosidase inhibitory activities are shown.
Collapse
Affiliation(s)
- Wataru Hakamata
- Division of Organic Chemistry, National Institute of Health Sciences, Setagaya-ku, Tokyo 158-8501, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Matsubara K, Saito A, Tanaka A, Nakajima N, Akagi R, Mori M, Mizushina Y. Catechin conjugated with fatty acid inhibits DNA polymerase and angiogenesis. DNA Cell Biol 2006; 25:95-103. [PMID: 16460233 DOI: 10.1089/dna.2006.25.95] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Catechins in green tea have anticancer and antiangiogenesis activities, with epigallocatechin-3-gallate (EGCG) being the most potent antiangiogenic tea catechin. This study examined whether chemical modification of catechin enhanced anticancer and antiangiogenic effects. Catechin, conjugated with fatty acid (acyl-catechin), strongly inhibited DNA polymerase, HL-60 cancer cell growth, and angiogenesis. Catechin conjugated with stearic acid [(2R,3S)-3',4',5,7-tetrahydroxyflavan-3-yl octadecanoate; catechin-C18] was the strongest inhibitor in DNA polymerase alpha and beta and angiogenesis assays. Catechin-C18 also suppressed human endothelial cell (HUVEC) tube formation on the reconstituted basement membrane, suggesting that it affected not only DNA polymerases but also signal transduction pathways in HUVECs. These data indicate that acyl-catechins target both DNA polymerases and angiogenesis as anticancer agents. These results suggest that acylation of catechin is an effective chemical modification to improve the anticancer activity of catechin.
Collapse
Affiliation(s)
- Kiminori Matsubara
- Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, Soja, Okayama 719-1197, Japan.
| | | | | | | | | | | | | |
Collapse
|
34
|
Abstract
A theaflavin-related benzotropolone pigment formed between procyanidin B-1 and (-)-epigallocatechin was synthesized enzymatically for the first time. The condensation occurred regioselectively at the extension (upper) unit of the procyanidin, probably due to a steric effect.
Collapse
Affiliation(s)
- Takashi Tanaka
- Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | | | | |
Collapse
|
35
|
Dell'agli M, Bellosta S, Rizzi L, Galli GV, Canavesi M, Rota F, Parente R, Bosisio E, Romeo S. A structure-activity study for the inhibition of metalloproteinase-9 activity and gene expression by analogues of gallocatechin-3-gallate. Cell Mol Life Sci 2005; 62:2896-903. [PMID: 16314917 DOI: 10.1007/s00018-005-5422-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Catechins are able to modulate the gelatinolytic activity of matrix metalloproteinase-9 (MMP-9) by reducing its release from macrophages. Gallocatechins decrease MMP-9 secretion by lowering MMP-9 promoter activity and mRNA levels. The effect appears to be dependent on some structural and stereochemical requirements. In this study, the relationship between chemical structure and activity was studied by testing the effect of analogues of (+/-)-gallocatechin-3-gallate (+/-)-GCG, selectively deprived of hydroxyl groups, on MMP-9 activity, transcription, and secretion. Our results indicate that (+/-)-GCG and (+/-)-catechin-3-gallate are characterized by a substitution pattern compatible with direct inhibition of MMP-9 activity. Conversely, when transcription was the target, (+/-)-trans-3-flavanol-3-benzoate, lacking all the hydroxyl groups, was the most effective both in lowering MMP-9 promoter activity and consequently protein secretion, and in inhibiting nuclear-factor-kappaB-driven transcription. Our results suggest that the structural requirements for enzyme inhibition are different from those necessary for targeting gene expression.
Collapse
Affiliation(s)
- M Dell'agli
- Department of Pharmacological Sciences, University of Milan, Via Balzaretti 9, 20133, Milan, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Anderson JC, Headley C, Stapleton PD, Taylor PW. Synthesis and antibacterial activity of hydrolytically stable (-)-epicatechin gallate analogues for the modulation of beta-lactam resistance in Staphylococcus aureus. Bioorg Med Chem Lett 2005; 15:2633-5. [PMID: 15863332 PMCID: PMC2323490 DOI: 10.1016/j.bmcl.2005.03.063] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2005] [Accepted: 03/08/2005] [Indexed: 10/25/2022]
Abstract
Hydrolytically more stable analogues of (-)-epicatechin gallate (ECg) have been synthesised from ECg where an amine or amide function has been substituted for the ester linkage that joins the C-ring with the galloyl D-ring. Sub-inhibitory concentrations (25 mg/L) of the amide analogue 7, possessing the natural C-3 stereochemistry, were able to reduce the resistance to oxacillin of three strains of methicillin resistant Staphylococcus aureus (BB 568, EMRSA-15 and EMRSA-16) comparable to levels achieved with ECg.
Collapse
Affiliation(s)
- James C. Anderson
- School of Chemistry, University of Nottingham, Nottingham NG7 2RD, UK
- Corresponding authors. Fax: +44 (0) 1159513564 (J.C.A); fax: +44 (0) 2077535867 (P.W.T); e-mail addresses: ;
| | - Catherine Headley
- School of Chemistry, University of Nottingham, Nottingham NG7 2RD, UK
| | - Paul D. Stapleton
- Microbiology Group, School of Pharmacy, University of London, 29-39 Brunswick Square, London WC1 1AX, UK
| | - Peter W. Taylor
- Microbiology Group, School of Pharmacy, University of London, 29-39 Brunswick Square, London WC1 1AX, UK
- Corresponding authors. Fax: +44 (0) 1159513564 (J.C.A); fax: +44 (0) 2077535867 (P.W.T); e-mail addresses: ;
| |
Collapse
|
37
|
Saito A, Mizushina Y, Ikawa H, Yoshida H, Doi Y, Tanaka A, Nakajima N. Systematic synthesis of galloyl-substituted procyanidin B1 and B2, and their ability of DPPH radical scavenging activity and inhibitory activity of DNA polymerases. Bioorg Med Chem 2005; 13:2759-71. [PMID: 15781387 DOI: 10.1016/j.bmc.2005.02.023] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2005] [Revised: 02/15/2005] [Accepted: 02/15/2005] [Indexed: 11/23/2022]
Abstract
Six galloyl-substituted procyanidin B1 and B2, 3-O-gallate, 3''-O-gallate, and 3,3''-di-O-gallate, were systematically synthesized with the condensation method using TMSOTf as a catalyst. Their ability of DPPH radical scavenging activity and DNA polymerase inhibitory activity were also investigated. The results indicated that the galloyl group of these compounds is very important for both activities. 3,3''-Di-O-gallate dimers acted as strong inhibitor against DNA polymerase alpha and beta, whereas the desgalloyl and monogalloyl compounds did not exhibit any appreciable inhibitory activity against the DNA polymerase beta.
Collapse
Affiliation(s)
- Akiko Saito
- Biotechnology Center, Toyama Prefecture, Kosugi, Toyama 939-0398, Japan
| | | | | | | | | | | | | |
Collapse
|
38
|
Wan SB, Landis-Piwowar KR, Kuhn DJ, Chen D, Dou QP, Chan TH. Structure–activity study of epi-gallocatechin gallate (EGCG) analogs as proteasome inhibitors. Bioorg Med Chem 2005; 13:2177-85. [PMID: 15727870 DOI: 10.1016/j.bmc.2004.12.056] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2004] [Revised: 12/28/2004] [Accepted: 12/28/2004] [Indexed: 10/25/2022]
Abstract
The structure-activity relationship of a number of synthetic green tea polyphenol analogs involving modifications of A ring and B ring of epi-gallocatechin gallate (EGCG) as proteasome inhibitors has been examined. It was found that in B ring, a decrease in the number of OH groups led to decreased potency. Introduction of a hydrophobic benzyl group into the 8 position of A ring did not significantly affect the proteasome-inhibitory potency.
Collapse
Affiliation(s)
- Sheng Biao Wan
- Department of Applied Biology and Chemical Technology and the Open Laboratory of Chirotechnology, Institute of Molecular Technology for Drug Discovery and Synthesis, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, SAR, China
| | | | | | | | | | | |
Collapse
|
39
|
Tu YY, Xu XQ, Xia HL, Watanabe N. Optimization of theaflavin biosynthesis from tea polyphenols using an immobilized enzyme system and response surface methodology. Biotechnol Lett 2005; 27:269-74. [PMID: 15742149 DOI: 10.1007/s10529-004-8292-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2004] [Accepted: 12/13/2004] [Indexed: 11/26/2022]
Abstract
Theaflavins were synthesized from tea polyphenols extracted from green tea using an immobilized polyphenol oxidase system. To optimize the production of theaflavins, response surface methodology was applied to determine the effects of five critical variables and their mutual interactions on theaflavin biosynthesis at five levels. A total of 52 individual experiments were performed and a statistical model predicted that the highest theaflavin concentration was 0.766 mg ml(-1) at optimized conditions. Using these optimal parameters under experimental conditions in three independent replicates, the average value of the biosynthesized theaflavin concentration reached 0.75 +/- 0.017 mg ml(-1) and matched the value predicted by the model.
Collapse
Affiliation(s)
- You-Ying Tu
- Department of Tea Science, Zhejiang University, Hangzhou, PR China
| | | | | | | |
Collapse
|
40
|
Wan SB, Chen D, Dou QP, Chan TH. Study of the green tea polyphenols catechin-3-gallate (CG) and epicatechin-3-gallate (ECG) as proteasome inhibitors. Bioorg Med Chem 2005; 12:3521-7. [PMID: 15186836 DOI: 10.1016/j.bmc.2004.04.033] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2004] [Revised: 04/26/2004] [Accepted: 04/26/2004] [Indexed: 10/26/2022]
Abstract
The green tea polyphenol catechin-3-gallate (CG) and epicatechin-3-gallate (ECG) were synthesized enantioselectively via a Sharpless hydroxylation reaction followed by a diastereoselective cyclization. Their potencies to inhibit the proteasome activity were measured. The unnatural enantiomers were found to be equally potent to the natural compounds.
Collapse
Affiliation(s)
- Sheng Biao Wan
- Department of Applied Biology and Chemical Technology and the Open Laboratory of Chirotechnology, Institute of Molecular Technology for Drug Discovery and Synthesis, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, SAR, China
| | | | | | | |
Collapse
|
41
|
Saito A, Doi Y, Tanaka A, Matsuura N, Ubukata M, Nakajima N. Systematic synthesis of four epicatechin series procyanidin trimers and their inhibitory activity on the Maillard reaction and antioxidant activity. Bioorg Med Chem 2004; 12:4783-90. [PMID: 15336256 DOI: 10.1016/j.bmc.2004.07.024] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2004] [Revised: 07/10/2004] [Accepted: 07/10/2004] [Indexed: 10/26/2022]
Abstract
A systematic synthesis of four natural epicatechin series procyanidin trimers [[4,8:4",8"]-2,3-cis-3,4-trans: 2",3"-cis-3",4"-trans: 2,3-trans-(-)-epi-catechin-(-)-epicatechin-(+)-catechin, [4,8:4",8"]-2,3-cis-3,4-trans: 2",3"-cis-3",4"-trans: 2,3-cis-tri-(-)-epicatechin: procyanidin C1, [4,8:4",8"]-2,3-cis-3,4-trans: 2",3"-trans-3",4"-trans: 2,3-trans-(-)-epicatechin-(+)-catechin-(+)-catechin: procyanidin C4, and [4,8:4",8"]-2,3-cis-3,4-trans: 2",3"-trans-3",4"-trans: 2,3-cis-(-)-epicatechin-(+)-catechin-(-)-epicatechin] is described. Condensation of (2R,3R,4S)-5,7,3'4'-tetra-O-benzyl-4-(2"-ethoxyethyloxy)flavan derived from (-)-epicatechin as an electrophile with the dimeric nucleophiles in the presence of TMSOTf followed by deprotection yielded trimers. Inhibitory activities on the Maillard reaction and antioxidant activity on lipid peroxide of the synthesized oligomers were also investigated.
Collapse
Affiliation(s)
- Akiko Saito
- Biotechnology Center, Toyama Prefecture, Kosugi, Toyama 939-0398, Japan
| | | | | | | | | | | |
Collapse
|
42
|
Ohmori K, Ushimaru N, Suzuki K. Oligomeric catechins: an enabling synthetic strategy by orthogonal activation and C(8) protection. Proc Natl Acad Sci U S A 2004; 101:12002-7. [PMID: 15141082 PMCID: PMC514424 DOI: 10.1073/pnas.0401651101] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2004] [Accepted: 04/06/2004] [Indexed: 11/18/2022] Open
Abstract
Controlled formation of oligomeric catechins has become possible by an orthogonal synthetic strategy. Bromo-capping of the C(8) position of the flavan skeleton enabled the equimolar coupling of electrophilic and nucleophilic catechin derivatives, enabling an efficient synthetic strategy to complex catechin oligomers.
Collapse
Affiliation(s)
- Ken Ohmori
- Department of Chemistry, Tokyo Institute of Technology, and Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, O-okayama, Meguro-ku, Tokyo 152-8551, Japan
| | | | | |
Collapse
|
43
|
Sang S, Tian S, Stark RE, Yang CS, Ho CT. New dibenzotropolone derivatives characterized from black tea using LC/MS/MS. Bioorg Med Chem 2004; 12:3009-17. [PMID: 15142559 DOI: 10.1016/j.bmc.2004.03.027] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2003] [Revised: 03/02/2004] [Accepted: 03/14/2004] [Indexed: 01/23/2023]
Abstract
Theaflavins and thearubigins are major pigments in black tea, and it is generally accepted that they are produced by oxidation of flavan-3-ols (catechins) during tea fermentation. In the course of studies on the oxidation mechanism of tea polyphenols, especially the formation of thearubigins, a method combining the enzymatic synthesis and LC/ESI-MS/MS analysis was developed to search for new higher molecular weight polymers from black tea. Three new dibenzotropolones, theadibenzotropolone A, B, and C, together with one new tribenzotropolone, theatribenzotropolone A, were formed by the reaction of theaflavins and tea catechins with horseradish peroxidase in the presence of H(2)O(2). The structures of these new benzotropolone derivatives were elucidated on the basis of MS and 2D NMR spectroscopic analyses. The existence of these compounds in black tea was characterized by LC/ESI-MS/MS. Theadibenzotropolone A and B were the first benzotropolone-type trimers of catechins found in the black tea extract. The observation that galloyl ester groups of theaflavins can be oxidized to form di- or tri-benzotropolone skeletons strongly implied that this type of oxidation is an important pathway to extend the molecular size of thearubigins.
Collapse
Affiliation(s)
- Shengmin Sang
- Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers University, 164 Frelinghuysen Road, Piscataway, NJ 08854-8020, USA.
| | | | | | | | | |
Collapse
|
44
|
Abstract
Gelatin-catechin conjugate was synthesized by the laccase-catalyzed oxidation of catechin in the presence of gelatin. The conjugate had a good scavenging activity against superoxide anion radicals. Moreover, the conjugate showed an amplified inhibition effect on human low density lipoprotein oxidation initiated by 2,2'-azobis(2-amidinopropane)dihydrochloride as a radical generator.
Collapse
Affiliation(s)
- Joo Eun Chung
- Bio-oriented Technology Research Advancement Institute, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | | | | | | |
Collapse
|
45
|
Sang S, Tian S, Wang H, Stark RE, Rosen RT, Yang CS, Ho CT. Chemical studies of the antioxidant mechanism of tea catechins: radical reaction products of epicatechin with peroxyl radicals. Bioorg Med Chem 2003; 11:3371-8. [PMID: 12878131 DOI: 10.1016/s0968-0896(03)00367-5] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Tea catechins, an important class of polyphenols, have been shown to have antioxidant activity and are thought to act as antioxidants in biological systems. However, the mechanisms of their antioxidant reactions remain unclear. The objective of this study was to characterize the reaction products of epicatechin with peroxyl radicals generated by thermolysis of the azo initiator azo-bisisobutyrylnitrile (AIBN). Structural elucidation of these products can provide insights into specific mechanisms of antioxidant reactions. Eight reaction products were isolated and identified using high-field 1D and 2D NMR spectral analysis. The observation of these compounds confirmed that the B-ring is the initial site for formation of reaction products in the peroxyl radical oxidant system.
Collapse
Affiliation(s)
- Shengmin Sang
- Department of Food Science and Center for Advanced Food Technology, Rutgers University, 65 Dudley Road, New Brunswick, NJ 08901-8520, USA.
| | | | | | | | | | | | | |
Collapse
|
46
|
Saito T, Miyake M, Toba M, Okamatsu H, Shimizu S, Noda M. Inhibition by apple polyphenols of ADP-ribosyltransferase activity of cholera toxin and toxin-induced fluid accumulation in mice. Microbiol Immunol 2003; 46:249-55. [PMID: 12061627 DOI: 10.1111/j.1348-0421.2002.tb02693.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The effects of crude polyphenol extracted from immature apples on the enzymatic and biological activities of a cholera toxin (CT) were investigated. When the apple polyphenol extract (APE) was examined for properties to inhibit CT-catalyzed ADP-ribosylation of agmatine, it was found that APE inhibited it in a dose-dependent manner. The concentration of APE to inhibit 50% of the enzymatic activity of CT (15 microg/ml) was approximately 8.7 microg/ml. The APE also diminished CT-induced fluid accumulation in two diarrhea models for in vivo mice. In the ligated ileum loops, 25 microg of APE significantly inhibited fluid accumulation induced by 500 ng of CT. In a sealed mouse model, even when APE was administered orally 10 min after a toxin injection, fluid accumulation was significantly inhibited at a comparable dosage. Lineweaver-Burk analysis demonstrated that APE had negative allosteric effects on CT-catalyzed NAD: agmatine ADP-ribosyltransferase. We fractionated the APE into four fractions using LH-20 Sephadex resin. One of the fractions, FAP (fraction from apple polyphenol) 1, which contains non-catechin polyphenols, did not significantly inhibit the CT-catalyzed ADP-ribosylation of agmatine. FAP2, which contains compounds with monomeric, dimeric, and trimeric catechins, inhibited the ADP-ribosylation only partially, but significantly. FAP3 and FAP4, which consist of highly polymerized catechin compounds, strongly inhibited the ADP-ribosylation, indicating that the polymerized structure of catechin is responsible for the inhibitory effect that resides in APE. The results suggest that polymerized catechin compounds in APE inhibit the biological and enzymatic activities of CT and can be used in a precautionary and therapeutic manner in the treatment of cholera patients.
Collapse
Affiliation(s)
- Takao Saito
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, Japan
| | | | | | | | | | | |
Collapse
|
47
|
Abstract
3,5,7,3',4'-Pentaacetyl catechin was selectively hydrolyzed to either 3,7,3',4'-tetraacetyl catechin or 3-acetyl catechin depending upon the duration of hydrolysis. A similar result was also obtained in the epicatechin series.
Collapse
Affiliation(s)
- Amit Basak
- Department of Chemistry, Indian Institute of Technology, Kharagpur 721302, India.
| | | | | |
Collapse
|
48
|
Kozikowski AP, Tückmantel W, Böttcher G, Romanczyk LJ. Studies in polyphenol chemistry and bioactivity. 4.(1) Synthesis of trimeric, tetrameric, pentameric, and higher oligomeric epicatechin-derived procyanidins having all-4beta,8-interflavan connectivity and their inhibition of cancer cell growth through cell cycle arrest. J Org Chem 2003; 68:1641-58. [PMID: 12608775 DOI: 10.1021/jo020393f] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report an improved synthesis of bis(5,7,3',4'-tetra-O-benzyl)epicatechin 4beta,8-dimer (3) from 5,7,3',4'-tetra-O-benzylepicatechin (1) and 5,7,3',4'-tetra-O-benzyl-4-(2-hydroxyethoxy)epicatechin (2) by replacing the previously employed Lewis acid, titanium tetrachloride, with the clay mineral Bentonite K-10. Under the same conditions, the benzyl-protected all-4beta,8-trimer, -tetramer, and -pentamer were obtained regioselectively from their lower homologues, albeit in rapidly decreasing yields. Reaction of 2 with an organoaluminum thiolate generated from 2-mercaptobenzothiazole and trimethylaluminum followed by acetylation produced 3-O-acetyl-4-[(2-benzothiazolyl)thio]-5,7,3',4'-tetra-O-benzylepicatechin (12). Medium-sized protected oligomers with 4beta,8-interflavan linkages are obtained in improved yields by using this compound as the electrophile and silver tetrafluoroborate as activator and are isolated by reversed-phase HPLC. Their deprotection by ester saponification followed by hydrogenolysis yielded the free procyanidins, which were characterized as their peracetates. The synthetic procyanidins are identical by normal-phase HPLC with fractions isolated from cocoa. The principle of chain extension by two members was demonstrated using a dimeric electrophile obtained by self-condensation of compound 12. Both the synthetic and natural pentamer 32 inhibit the growth of several breast cancer cell lines. Using the MDA MB 231 line, it was established that this outcome is based on the induction of cell cycle arrest in the G0/G1 phase. Subsequent cell death is more likely necrotic rather than apoptotic. Control experiments demonstrate that the polyphenol itself, rather than hydrogen peroxide potentially formed by its autoxidation, is the causative agent.
Collapse
Affiliation(s)
- Alan P Kozikowski
- Georgetown University Medical Center, Department of Neurology, Drug Discovery Laboratory, 3900 Reservoir Road NW, Washington, DC 20007, USA.
| | | | | | | |
Collapse
|
49
|
Abstract
Conformational activation of antithrombin is a critical mechanism for the inhibition of factor Xa, a proteinase of the blood coagulation cascade, and is typically achieved with heparin, a polyanionic polysaccharide clinically used for anticoagulation. Although numerous efforts have been directed toward the design of better activators, a fundamental tenet of these studies has been the assumed requirement of an oligo- or a polysaccharide backbone. We demonstrate here a concept that small nonsaccharidic nonpolymeric molecules may be rationally designed to interact with and activate antithrombin for enhanced inhibition of factor Xa. The rational design strategy is based on a study of complexes of natural and mutant antithrombins with heparin-based oligosaccharides using hydropathic interaction (HINT) technique, a quantitative computerized tool for analysis of molecular interactions. A linear correlation was observed between the free energy of binding for antithrombinminus signoligosaccharide complexes and the HINT score over a wide range of approximately 13 kcal/mol, indicating strong predictive capability of the HINT technique. Using this approach, a small, nonsugar, aromatic molecule, (minus sign)-epicatechin sulfate (ECS), was designed to mimic the nonreducing end trisaccharide unit DEF of the sequence specific heparin pentasaccharide DEFGH. HINT suggested a comparable antithrombin-binding geometry and interaction profile for ECS and trisaccharide DEF. Biochemical studies indicated that ECS binds antithrombin with equilibrium dissociation constants of 10.5 and 66 microM at pH 6.0, I 0.025, and pH 7.4, I 0.035, respectively, that compare favorably with 2 and 80 microM observed for the natural activator DEF. ECS accelerates the antithrombin inhibition of factor Xa nearly 8-fold demonstrating for the first time that conformational activation of antithrombin is feasible with appropriately designed small nonsugar organic molecules. The results present unique opportunities for de novo activator design based on this first-generation lead.
Collapse
Affiliation(s)
- Gunnar T Gunnarsson
- Department of Medicinal Chemistry, Virginia Commonwealth University, 410 North 12th Street, P.O. Box 980540, Richmond, Virginia 23298, USA
| | | |
Collapse
|
50
|
Tillekeratne LMV, Sherette A, Fulmer JA, Hupe L, Hupe D, Gabbara S, Peliska JA, Hudson RA. Differential inhibition of polymerase and strand-transfer activities of HIV-1 reverse transcriptase. Bioorg Med Chem Lett 2002; 12:525-8. [PMID: 11844664 DOI: 10.1016/s0960-894x(01)00827-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new class of inhibitors of HIV-1 reverse transcriptase obtained by the systematic structural simplification of epicatechin and epigallocatechin gallates are also shown here to inhibit DNA-strand-transfer, a process critical to the completion of the HIV-1-RT reproduction and to recombination-associated mutation of the virus. Up to 80-fold selectivity for DNA-strand-transfer inhibition over polymerase inhibition was observed for a defined subset of these agents. Such specific DNA-strand-transfer inhibitors may have important therapeutic potential.
Collapse
Affiliation(s)
- L M Viranga Tillekeratne
- Department of Medicinal and Biological Chemistry, College of Pharmacy, University of Toledo, Toledo, OH 43606, USA
| | | | | | | | | | | | | | | |
Collapse
|