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Yang KH, Yen CY, Wang SC, Chang FR, Chang MY, Chan CK, Jeng JH, Tang JY, Chang HW. 6- n-Butoxy-10-nitro-12,13-dioxa-11-azatricyclo[7.3.1.0 2,7]trideca-2,4,6,10-tetraene Improves the X-ray Sensitivity on Inhibiting Proliferation and Promoting Oxidative Stress and Apoptosis of Oral Cancer Cells. Biomedicines 2024; 12:458. [PMID: 38398060 PMCID: PMC10887088 DOI: 10.3390/biomedicines12020458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Revised: 02/09/2024] [Accepted: 02/16/2024] [Indexed: 02/25/2024] Open
Abstract
This in vitro study examines the anti-oral cancer effects and mechanisms of a combined X-ray/SK2 treatment, i.e., X-ray and 6-n-butoxy-10-nitro-12,13-dioxa-11-azatricyclo[7.3.1.02,7]trideca-2,4,6,10-tetraene (SK2). ATP cell viability and flow cytometry-based cell cycle, apoptosis, oxidative stress, and DNA damage assessments were conducted. The X-ray/SK2 treatment exhibited lower viability in oral cancer (Ca9-22 and CAL 27) cells than in normal (Smulow-Glickman, S-G) cells, i.e., 32.0%, 46.1% vs. 59.0%, which showed more antiproliferative changes than with X-ray or SK2 treatment. Oral cancer cells under X-ray/SK2 treatment showed slight subG1 and G2/M increments and induced high annexin V-monitored apoptosis compared to X-ray or SK2 treatment. The X-ray/SK2 treatment showed higher caspase 3 and 8 levels for oral cancer cells than other treatments. X-ray/SK2 showed a higher caspase 9 level in CAL 27 cells than other treatments, while Ca9-22 cells showed similar levels under X-ray and/or SK2. The X-ray/SK2 treatment showed higher reactive oxygen species (ROS) generation and mitochondrial membrane potential (MMP) depletion than other treatments. Meanwhile, the mitochondrial superoxide (MitoSOX) and glutathione levels in X-ray/SK2 treatment did not exhibit the highest rank compared to others. Moreover, oral cancer cells had higher γH2AX and/or 8-hydroxy-2-deoxyguanosine levels from X-ray/SK2 treatment than others. All these measurements for X-ray/SK2 in oral cancer cells were higher than in normal cells and attenuated by N-acetylcysteine. In conclusion, X-ray/SK2 treatment showed ROS-dependent enhanced antiproliferative, apoptotic, and DNA damage effects in oral cancer cells with a lower cytotoxic influence on normal cells.
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Affiliation(s)
- Kun-Han Yang
- Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (K.-H.Y.); (F.-R.C.)
| | - Ching-Yu Yen
- School of Dentistry, Taipei Medical University, Taipei 11031, Taiwan;
- Department of Oral and Maxillofacial Surgery, Chi-Mei Medical Center, Tainan 71004, Taiwan
| | - Sheng-Chieh Wang
- Department of Biomedical Science and Environmental Biology, PhD Program in Life Sciences, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
| | - Fang-Rong Chang
- Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (K.-H.Y.); (F.-R.C.)
| | - Meng-Yang Chang
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
| | - Chieh-Kai Chan
- Department of Chemistry, University of Illinois Urbana, Champaign, IL 61820, USA;
| | - Jiiang-Huei Jeng
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
- Department of Dentistry, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan
- Department of Dentistry, National Taiwan University Hospital, Taipei 100225, Taiwan
| | - Jen-Yang Tang
- School of Post-Baccalaureate Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Department of Radiation Oncology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Hsueh-Wei Chang
- Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (K.-H.Y.); (F.-R.C.)
- Department of Biomedical Science and Environmental Biology, PhD Program in Life Sciences, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
- Center for Cancer Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan
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Wang SC, Yen CY, Shiau JP, Chang MY, Hou MF, Tang JY, Chang HW. Combined Treatment of Nitrated [6,6,6]Tricycles Derivative (SK2)/Ultraviolet C Highly Inhibits Proliferation in Oral Cancer Cells In Vitro. Biomedicines 2022; 10:biomedicines10051196. [PMID: 35625933 PMCID: PMC9138449 DOI: 10.3390/biomedicines10051196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 05/19/2022] [Accepted: 05/20/2022] [Indexed: 11/16/2022] Open
Abstract
Combined treatment is an effective strategy to improve anticancer therapy, but severe side effects frequently limit this application. Drugs inhibiting the proliferation of cancer cells, but not normal cells, display preferential antiproliferation to cancer cells. It shows the benefits of avoiding side effects and enhancing antiproliferation for combined treatment. Nitrated [6,6,6]tricycles derivative (SK2), a novel chemical exhibiting benzo-fused dioxabicyclo[3.3.1]nonane core with an n-butyloxy substituent, exhibiting preferential antiproliferation, was chosen to evaluate its potential antioral cancer effect in vitro by combining it with ultraviolet C (UVC) irradiation. Combination treatment (UVC/SK2) caused lower viability in oral cancer cells (Ca9-22 and OC-2) than single treatment (20 J/m2 UVC or 10 μg/mL SK2), i.e., 42.3%/41.1% vs. 81.6%/69.2%, and 89.5%/79.6%, respectively. In contrast, it showed a minor effect on cell viability of normal oral cells (HGF-1), ranging from 82.2 to 90.6%. Moreover, UVC/SK2 caused higher oxidative stress in oral cancer cells than normal cells through the examination of reactive oxygen species, mitochondrial superoxide, and mitochondrial membrane potential. UVC/SK2 also caused subG1 increment associated with apoptosis detections by assessing annexin V; panaspase; and caspases 3, 8, and 9. The antiproliferation and oxidative stress were reverted by N-acetylcysteine, validating the involvement of oxidative stress in antioral cancer cells. UVC/SK2 also caused DNA damage by detecting γH2AX and 8-hydroxy-2′-deoxyguanosine in oral cancer cells. In conclusion, SK2 is an effective enhancer for improving the UVC-caused antiproliferation against oral cancer cells in vitro. UVC/SK2 demonstrated a preferential and synergistic antiproliferation ability towards oral cancer cells with little adverse effects on normal cells.
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Affiliation(s)
- Sheng-Chieh Wang
- Department of Biomedical Science and Environmental Biology, Ph.D. Program in Life Sciences, College of Life Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (S.-C.W.); (M.-F.H.)
| | - Ching-Yu Yen
- Department of Oral and Maxillofacial Surgery Chi-Mei Medical Center, Tainan 71004, Taiwan;
- School of Dentistry, Taipei Medical University, Taipei 11031, Taiwan
| | - Jun-Ping Shiau
- Department of Surgery, Kaohsiung Municipal Siaogang Hospital, Kaohsiung 81267, Taiwan;
- Division of Breast Oncology and Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Meng-Yang Chang
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
| | - Ming-Feng Hou
- Department of Biomedical Science and Environmental Biology, Ph.D. Program in Life Sciences, College of Life Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (S.-C.W.); (M.-F.H.)
- Department of Surgery, Kaohsiung Municipal Siaogang Hospital, Kaohsiung 81267, Taiwan;
- Division of Breast Oncology and Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Jen-Yang Tang
- School of Post-Baccalaureate Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Department of Radiation Oncology, Kaohsiung Medical University Hospital, Kaoshiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: (J.-Y.T.); (H.-W.C.); Tel.: +7-886-7-312-1101 (ext. 7158) (J.-Y.T.); +7-886-7-312-1101 (ext. 2691) (H.-W.C.)
| | - Hsueh-Wei Chang
- Department of Biomedical Science and Environmental Biology, Ph.D. Program in Life Sciences, College of Life Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (S.-C.W.); (M.-F.H.)
- Center for Cancer Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: (J.-Y.T.); (H.-W.C.); Tel.: +7-886-7-312-1101 (ext. 7158) (J.-Y.T.); +7-886-7-312-1101 (ext. 2691) (H.-W.C.)
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Wang SC, Yen CY, Shiau JP, Chang MY, Hou MF, Jeng JH, Tang JY, Chang HW. Synergistic Antiproliferation of Cisplatin and Nitrated [6,6,6]Tricycle Derivative (SK2) for a Combined Treatment of Oral Cancer Cells. Antioxidants (Basel) 2022; 11:antiox11050926. [PMID: 35624790 PMCID: PMC9137724 DOI: 10.3390/antiox11050926] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/02/2022] [Accepted: 05/06/2022] [Indexed: 12/19/2022] Open
Abstract
SK2, a nitrated [6,6,6]tricycle derivative with an n-butyloxy group, showed selective antiproliferation effects on oral cancer but not on normal oral cells. This investigation assessed for the first time the synergistic antiproliferation potential of cisplatin/SK2 in oral cancer cells. Cell viability assay at 24 h showed that a low dose of combined cisplatin/SK2 (10 μM/10 μg/mL) provided more antiproliferation than cisplatin or SK2 alone. Cisplatin/SK2 triggered also more apoptosis inductions in terms of subG1 accumulation, annexin V, pancaspase, and caspase 3/8/9 measurements. Moreover, cisplatin/SK2 provided more oxidative stress and DNA damage in oral cancer cells than independent treatments. Oxidative stress inhibitors rescued the cisplatin/SK2-induced antiproliferation and oxidative stress generation. Moreover, cisplatin/SK2 induced more antiproliferation, apoptosis, oxidative stress, and DNA damage in oral cancer cells than in normal oral cells (S-G). In conclusion, low-dose cisplatin/SK2 combined treatment promoted selective and synergistic antiproliferation in oral cancer cells depending on oxidative-stress-associated responses.
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Affiliation(s)
- Sheng-Chieh Wang
- Ph.D. Program in Life Sciences, Department of Biomedical Science and Environmental Biology, College of Life Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (S.-C.W.); (M.-F.H.)
| | - Ching-Yu Yen
- Department of Oral and Maxillofacial Surgery, Chi-Mei Medical Center, Tainan 71004, Taiwan;
- School of Dentistry, Taipei Medical University, Taipei 11031, Taiwan
| | - Jun-Ping Shiau
- Division of Breast Oncology and Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
- Department of Surgery, Kaohsiung Municipal Siaogang Hospital, Kaohsiung 81267, Taiwan
| | - Meng-Yang Chang
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
| | - Ming-Feng Hou
- Ph.D. Program in Life Sciences, Department of Biomedical Science and Environmental Biology, College of Life Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (S.-C.W.); (M.-F.H.)
- Division of Breast Oncology and Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
| | - Jiiang-Huei Jeng
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
- Department of Dentistry, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan
- Department of Dentistry, National Taiwan University Hospital, Taipei 100225, Taiwan
| | - Jen-Yang Tang
- School of Post-Baccalaureate Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Department of Radiation Oncology, Kaohsiung Medical University Hospital, Kaoshiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: (J.-Y.T.); (H.-W.C.); Tel.: +886-7-312-1101 (ext. 7158) (J.-Y.T.); +886-7-312-1101 (ext. 2691) (H.-W.C.)
| | - Hsueh-Wei Chang
- Ph.D. Program in Life Sciences, Department of Biomedical Science and Environmental Biology, College of Life Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (S.-C.W.); (M.-F.H.)
- Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
- Center for Cancer Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: (J.-Y.T.); (H.-W.C.); Tel.: +886-7-312-1101 (ext. 7158) (J.-Y.T.); +886-7-312-1101 (ext. 2691) (H.-W.C.)
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Wang SC, Chang MY, Shiau JP, Farooqi AA, Huang YH, Tang JY, Chang HW. Antiproliferation- and Apoptosis-Inducible Effects of a Novel Nitrated [6,6,6]Tricycle Derivative (SK2) on Oral Cancer Cells. Molecules 2022; 27:1576. [PMID: 35268676 PMCID: PMC8911617 DOI: 10.3390/molecules27051576] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 02/19/2022] [Accepted: 02/25/2022] [Indexed: 12/01/2022] Open
Abstract
The benzo-fused dioxabicyclo[3.3.1]nonane core is the central framework in several natural products. Using this core, we had developed a novel nitrated [6,6,6]tricycle-derived compound containing an n-butyloxy group, namely, SK2. The anticancer potential of SK2 was not assessed. This study aimed to determine the antiproliferative function and investigated possible mechanisms of SK2 acting on oral cancer cells. SK2 preferentially killed oral cancer cells but caused no harmful effect on non-malignant oral cells. After the SK2 exposure of oral cancer cells, cells in the sub-G1 phase accumulated. This apoptosis-like outcome of SK2 treatment was validated to be apoptosis via observing an increasing annexin V population. Mechanistically, apoptosis signalers such as pancaspase, caspases 8, caspase 9, and caspase 3 were activated by SK2 in oral cancer cells. SK2 induced oxidative-stress-associated changes. Furthermore, SK2 caused DNA damage (γH2AX and 8-hydroxy-2'-deoxyguanosine). In conclusion, a novel nitrated [6,6,6]tricycle-derived compound, SK2, exhibits a preferential antiproliferative effect on oral cancer cells, accompanied by apoptosis, oxidative stress, and DNA damage.
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Affiliation(s)
- Sheng-Chieh Wang
- Department of Biomedical Science and Environmental Biology, Ph.D. Program in Life Sciences, College of Life Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
| | - Meng-Yang Chang
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
| | - Jun-Ping Shiau
- Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan;
- Division of Breast Surgery and Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan
| | - Ammad Ahmad Farooqi
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad 54000, Pakistan;
| | - Yu-Hsiang Huang
- Post-Graduate Year Training (PGY), Department of Clinical Education and Training, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan;
| | - Jen-Yang Tang
- School of Post-Baccalaureate Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Department of Radiation Oncology, Kaohsiung Medical University Hospital, Kaoshiung Medical University, Kaohsiung 80708, Taiwan
| | - Hsueh-Wei Chang
- Department of Biomedical Science and Environmental Biology, Ph.D. Program in Life Sciences, College of Life Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
- Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
- Center for Cancer Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
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Affiliation(s)
- Carmen Nájera
- Centro de Innovación en Química Avanzada (ORFEO−CINQA), Universidad de Alicante, Apdo. 99, Alicante E-03080, Spain
| | - Leiv K. Sydnes
- Department of Chemistry, University of Bergen, Allégt. 41, Bergen NO-5007, Norway
| | - Miguel Yus
- Centro de Innovación en Química Avanzada (ORFEO−CINQA), Universidad de Alicante, Apdo. 99, Alicante E-03080, Spain
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Furey A, O'Doherty S, O'Callaghan K, Lehane M, James KJ. Azaspiracid poisoning (AZP) toxins in shellfish: Toxicological and health considerations. Toxicon 2010; 56:173-90. [DOI: 10.1016/j.toxicon.2009.09.009] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2008] [Accepted: 09/18/2009] [Indexed: 11/29/2022]
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Li J, Li X, Mootoo DR. Synthetic and Computational Studies on the ABC Trioxadispiroketal Subunit of the Marine Biotoxin Azaspiracid-1. Nat Prod Commun 2008. [DOI: 10.1177/1934578x0800301106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The trioxadispiroketal residue in the marine biotoxin azaspiracid-1, which exists in a configuration capable of exhibiting a double anomeric effect, is believed to be the thermodynamically most stable bis-spiroketal diastereomer. In order to get insight into how structural factors affect this equilibrium, a simplified ABC trioxadispiroketal analog of azaspiracid-1 was synthesized and subjected to equilbration and computational studies. Compound 7, which represents a double anomeric effect was obtained as the major isomer, together with diastereomers 14 and 15, in a respective ratio of 62:22:16. DFT calculations for 7, 14 and 15 qualitatively matched this observation. These results suggest that while a double anomeric effect may play a major role in the stability of the trioxadispiroketal configuration in the more complex natural product, the substitution pattern of the C ring is also a contributing factor.
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Affiliation(s)
- Jialiang Li
- Department of Chemistry, Hunter College/CUNY, New York, NY 10021, USA
| | - Xiaohua Li
- Department of Chemistry, Hunter College/CUNY, New York, NY 10021, USA
| | - David R. Mootoo
- Department of Chemistry, Hunter College/CUNY, New York, NY 10021, USA
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Nicolaou KC, Snyder SA. Chasing molecules that were never there: misassigned natural products and the role of chemical synthesis in modern structure elucidation. Angew Chem Int Ed Engl 2007; 44:1012-1044. [PMID: 15688428 DOI: 10.1002/anie.200460864] [Citation(s) in RCA: 479] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Over the course of the past half century, the structural elucidation of unknown natural products has undergone a tremendous revolution. Before World War II, a chemist would have relied almost exclusively on the art of chemical synthesis, primarily in the form of degradation and derivatization reactions, to develop and test structural hypotheses in a process that often took years to complete when grams of material were available. Today, a battery of advanced spectroscopic methods, such as multidimensional NMR spectroscopy and high-resolution mass spectrometry, not to mention X-ray crystallography, exist for the expeditious assignment of structures to highly complex molecules isolated from nature in milligram or sub-milligram quantities. In fact, it could be argued that the characterization of natural products has become a routine task, one which no longer even requires a reaction flask! This Review makes the case that imaginative detective work and chemical synthesis still have important roles to play in the process of solving nature's most intriguing molecular puzzles.
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Affiliation(s)
- K C Nicolaou
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA, Fax: (+1) 858-784-2469
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Scott A Snyder
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA, Fax: (+1) 858-784-2469
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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Nicolaou KC, Snyder SA. Die Jagd auf Moleküle, die nie existiert haben: Falsch zugeordnete Naturstoffstrukturen und die Rolle der chemischen Synthese in der modernen Strukturaufklärung. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200460864] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- K. C. Nicolaou
- Department of Chemistry und The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA, Fax: (+1) 858‐784‐2469
- Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Scott A. Snyder
- Department of Chemistry und The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA, Fax: (+1) 858‐784‐2469
- Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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James KJ, Sierra MD, Lehane M, Braña Magdalena A, Furey A. Detection of five new hydroxyl analogues of azaspiracids in shellfish using multiple tandem mass spectrometry. Toxicon 2003; 41:277-83. [PMID: 12565749 DOI: 10.1016/s0041-0101(02)00288-x] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The polyether dinoflagellate toxins, azaspiracids, are responsible for azaspiracid poisoning (AZP), a new human toxic syndrome arising from the consumption of shellfish. To date, five azaspiracids have been isolated and fully structurally elucidated, including, AZA1, its 8-methyl and 22-demethyl analogues, AZA2 and AZA3, respectively, and two hydroxyl derivatives of AZA3, named AZA4 and AZA5. Using a recently developed method involving liquid chromatography with multiple tandem mass spectrometry (LC-MS(n)), five new azaspiracids, AZA7-AZA11, have been found in mussels (Mytilus edulis). AZA6 is a positional isomer of AZA1 and four of the new compounds are isomers with a mass of 857.5 amu. AZA7 and AZA8 are hydroxyl analogues of AZA1 while AZA9 and AZA10 are hydroxyl analogues of AZA6. AZA11 is a hydroxyl analogue of AZA2. The separation of all 11 azaspiracids was achieved using isocratic reversed phase liquid chromatography using a combination of eluent additives, trifluoroacetic acid and ammonium acetate. The ion-trap MS experiments, with electrospray ionisation, involved the fragmentation of the protonated molecule [M+H](+), trapping and fragmenting the product ions due to the loss of a water molecule [M+H-H(2)O](+), together with mass spectral data analysis that included the characteristic A-ring fragmentation for each compound.
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Affiliation(s)
- Kevin J James
- PROTEOBIO, Department of Chemistry, Mass Spectrometry Centre for Proteomics and Biotoxin Research, Cork Institute of Technology, Bishopstown, Cork, Ireland.
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Forsyth CJ, Hao J, Aiguade J. Synthesis of the (+)‐C26–C40 Domain of the Azaspiracids by a Novel Double Intramolecular Hetero‐Michael Addition Strategy. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3757(20011001)113:19<3775::aid-ange3775>3.0.co;2-#] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Craig J. Forsyth
- Department of Chemistry Institute of Technology University of Minnesota Minneapolis, MN 55455, USA, Fax: (+1) 612‐626‐7541
| | - Junliang Hao
- Department of Chemistry Institute of Technology University of Minnesota Minneapolis, MN 55455, USA, Fax: (+1) 612‐626‐7541
| | - Josep Aiguade
- Department of Chemistry Institute of Technology University of Minnesota Minneapolis, MN 55455, USA, Fax: (+1) 612‐626‐7541
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