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Wu A, Chen Q, Feng J, Ye J, Xu X. Accurate Structural Elucidation of Samoquasine A and an Unknown Homologue Using a Computation-Based Machine Learning Protocol. J Phys Chem A 2024. [PMID: 38850258 DOI: 10.1021/acs.jpca.4c02916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2024]
Abstract
The structure of samoquasine A has long been a subject of controversy, which was resolved only upon its successful total synthesis. We examined the structures of the associated compounds using the state-of-the-art SVM-M protocol. The method accurately discriminated all putative structures historically attributed to samoquasine A from a pool of 48 isomeric structures, confirming that samoquasine A is indeed identical to perlolidine. Furthermore, by applying the SVM-M protocol to an additional pool of 67 isomeric structures, we successfully assigned a yet unknown natural product, initially misidentified as perlolidine, as a novel oxime, (E)-3H-cyclopenta[c]quinolin-3-one oxime, representing the first reported cyclone oxime-quinoline natural product.
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Affiliation(s)
- Anan Wu
- Fujian Provincial Key Laboratory for Theoretical and Computational Chemistry, Departmental of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Qiwen Chen
- Fujian Provincial Key Laboratory for Theoretical and Computational Chemistry, Departmental of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Jin Feng
- Fujian Provincial Key Laboratory for Theoretical and Computational Chemistry, Departmental of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Jianliang Ye
- Fujian Provincial Key Laboratory for Theoretical and Computational Chemistry, Departmental of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Xin Xu
- Collaborative Innovation Center of Chemistry for Energy Materials, Shanghai; Key Laboratory of Molecular Catalysis and Innovative Materials; MOE Key Laboratory of Computational Physical Sciences; Department of Chemistry, Fudan University, Shanghai 200438, China
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Elyashberg M, Tyagarajan S, Mandal M, Buevich AV. Enhancing Efficiency of Natural Product Structure Revision: Leveraging CASE and DFT over Total Synthesis. Molecules 2023; 28:molecules28093796. [PMID: 37175206 PMCID: PMC10180399 DOI: 10.3390/molecules28093796] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 04/21/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023] Open
Abstract
Natural products remain one of the major sources of coveted, biologically active compounds. Each isolated compound undergoes biological testing, and its structure is usually established using a set of spectroscopic techniques (NMR, MS, UV-IR, ECD, VCD, etc.). However, the number of erroneously determined structures remains noticeable. Structure revisions are very costly, as they usually require extensive use of spectroscopic data, computational chemistry, and total synthesis. The cost is particularly high when a biologically active compound is resynthesized and the product is inactive because its structure is wrong and remains unknown. In this paper, we propose using Computer-Assisted Structure Elucidation (CASE) and Density Functional Theory (DFT) methods as tools for preventive verification of the originally proposed structure, and elucidation of the correct structure if the original structure is deemed to be incorrect. We examined twelve real cases in which structure revisions of natural products were performed using total synthesis, and we showed that in each of these cases, time-consuming total synthesis could have been avoided if CASE and DFT had been applied. In all described cases, the correct structures were established within minutes of using the originally published NMR and MS data, which were sometimes incomplete or had typos.
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Affiliation(s)
- Mikhail Elyashberg
- Advanced Chemistry Development Inc. (ACD/Labs), Toronto, ON M5C 1B5, Canada
| | | | - Mihir Mandal
- Medicinal Chemistry, Merck & Co., Inc., Kenilworth, NJ 07033, USA
| | - Alexei V Buevich
- Analytical Research and Development, Merck & Co., Inc., Kenilworth, NJ 07033, USA
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3
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Chen Z, Wang S, Liu K, Zhang R, Li Q, Bian W, Qiao R, Li C. Practical and Scalable Manufacturing Process for the Key Intermediate of Poly(ADP-Ribose) Polymerase Inhibitor Olaparib. ACS OMEGA 2022; 7:6313-6321. [PMID: 35224393 PMCID: PMC8867798 DOI: 10.1021/acsomega.1c06920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
Olaparib (Lynparza) is a potent, highly selective inhibitor of poly(ADP-ribose)polymerase enzymes, approved by the U.S. FDA and EMA for the treatment of ovarian cancer. Herein, we report a practical, economical, and scalable process for the synthesis of 2-fluoro-5-((4-oxo-3,4-dihydrophthalazin-1-yl)methyl)benzoic acid, a key intermediate for olaparib. The low-cost industrial byproduct phthalhydrazide was used as the starting material to construct the phthalazinone moiety, which allowed access to the key intermediate by the Negishi coupling reaction. Optimization of each step has enabled the development of an environmentally benign and robust process with effective control of impurities.
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Synthesis of 3-(Bromomethylene)isobenzofuran-1(3H)-ones through regioselective 5-exo-dig bromocyclization of 2-alkynylbenzoic acids. Tetrahedron 2019. [DOI: 10.1016/j.tet.2018.11.045] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Wang YH, Liu JB, Ouyang B, Zhou H, Qiu G. TBAI-mediated regioselective 5-exo-dig iodinative oxocyclization of 2-alkynylbenzamides for the synthesis of isobenzofuran-1-imines and isobenzofurans. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.07.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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6
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Dhoro F, Parkin-Gibbs J, McIldowie M, Skelton BW, Piggott MJ. Confirmation of the Revised Structure of Samoquasine A and a Proposed Structural Revision of Cherimoline. JOURNAL OF NATURAL PRODUCTS 2018; 81:1658-1665. [PMID: 30020782 DOI: 10.1021/acs.jnatprod.8b00319] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The identity of the natural product samoquasine A has remained obscure since its isolation from custard apple seeds in 2000. One of the proposed structures, benzo[ f]phthalazin-4(3 H)-one, was prepared in two steps by regioselective ortho-lithiation/formylation of N, N-diisopropyl-2-naphthylamide, followed by cyclization with hydrazine, but was shown to be different from the natural product. Perlolidine, another candidate structure, was synthesized by a novel route involving a β-selective Heck reaction of butyl vinyl ether. Both perlolidine and samoquasine A are converted by trimethylsilyldiazomethane into the same N-methyl derivative. In addition, the 13C NMR spectra of perlolidine and another structurally mis-assigned natural product, cherimoline, are almost identical. Thus, both samoquasine A and cherimoline are actually perlolidine.
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Affiliation(s)
- Francis Dhoro
- Chemistry, School of Molecular Sciences , The University of Western Australia , Perth , WA 6009 , Australia
| | - Jesse Parkin-Gibbs
- Chemistry, School of Molecular Sciences , The University of Western Australia , Perth , WA 6009 , Australia
| | - Matthew McIldowie
- Chemistry, School of Molecular Sciences , The University of Western Australia , Perth , WA 6009 , Australia
| | - Brian W Skelton
- Chemistry, School of Molecular Sciences , The University of Western Australia , Perth , WA 6009 , Australia
| | - Matthew J Piggott
- Chemistry, School of Molecular Sciences , The University of Western Australia , Perth , WA 6009 , Australia
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Shang XF, Morris-Natschke SL, Liu YQ, Guo X, Xu XS, Goto M, Li JC, Yang GZ, Lee KH. Biologically active quinoline and quinazoline alkaloids part I. Med Res Rev 2018; 38:775-828. [PMID: 28902434 PMCID: PMC6421866 DOI: 10.1002/med.21466] [Citation(s) in RCA: 192] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 07/18/2017] [Accepted: 08/02/2017] [Indexed: 01/11/2023]
Abstract
Quinoline and quinazoline alkaloids, two important classes of N-based heterocyclic compounds, have attracted tremendous attention from researchers worldwide since the 19th century. Over the past 200 years, many compounds from these two classes were isolated from natural sources, and most of them and their modified analogs possess significant bioactivities. Quinine and camptothecin are two of the most famous and important quinoline alkaloids, and their discoveries opened new areas in antimalarial and anticancer drug development, respectively. In this review, we survey the literature on bioactive alkaloids from these two classes and highlight research achievements prior to the year 2008 (Part I). Over 200 molecules with a broad range of bioactivities, including antitumor, antimalarial, antibacterial and antifungal, antiparasitic and insecticidal, antiviral, antiplatelet, anti-inflammatory, herbicidal, antioxidant and other activities, were reviewed. This survey should provide new clues or possibilities for the discovery of new and better drugs from the original naturally occurring quinoline and quinazoline alkaloids.
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Affiliation(s)
- Xiao-Fei Shang
- School of Pharmacy, Lanzhou University, Lanzhou, P.R. China
- Key Laboratory of Veterinary Pharmaceutical Development of Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, P.R. China
| | - Susan L. Morris-Natschke
- Natural Products Research Laboratories, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina
| | - Ying-Qian Liu
- School of Pharmacy, Lanzhou University, Lanzhou, P.R. China
| | - Xiao Guo
- Key Laboratory of Veterinary Pharmaceutical Development of Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou, P.R. China
| | - Xiao-Shan Xu
- School of Pharmacy, Lanzhou University, Lanzhou, P.R. China
| | - Masuo Goto
- Natural Products Research Laboratories, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina
| | - Jun-Cai Li
- School of Pharmacy, Lanzhou University, Lanzhou, P.R. China
| | - Guan-Zhou Yang
- School of Pharmacy, Lanzhou University, Lanzhou, P.R. China
| | - Kuo-Hsiung Lee
- Natural Products Research Laboratories, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina
- Chinese Medicine Research and Development Center, China Medical University and Hospital, Taichung, Taiwan
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Lu D, Liu J, Zhang Y, Liu F, Zeng L, Peng R, Yang L, Ying H, Tang W, Chen W, Zuo J, Tong X, Liu T, Hu Y. Discovery and optimization of phthalazinone derivatives as a new class of potent dengue virus inhibitors. Eur J Med Chem 2018; 145:328-337. [PMID: 29335200 DOI: 10.1016/j.ejmech.2018.01.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 01/02/2018] [Accepted: 01/04/2018] [Indexed: 12/31/2022]
Abstract
Using a dengue replicon cell line-based screening, we identified 3-(dimethylamino)propyl(3-((4-(4-fluorophenyl)-1-oxophthalazin-2(1H)-yl)methyl)phenyl)carbamate (10a) as a potent DENV-2 inhibitor, with an IC50 value of 0.64 μM. A series of novel phthalazinone derivatives based on hit 10a were synthesized and evaluated for their in vitro anti-DENV activity and cytotoxicity. The subsequent SAR study and optimization led to the discovery of the most promising compound 14l, which displayed potent anti-DENV-2 activity, with low IC50 value against DENV-2 RNA replication of 0.13 μM and high selectivity (SI = 89.2) with acceptable pharmacokinetics profiles.
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Affiliation(s)
- Dong Lu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China; University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Jianan Liu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China; University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Yunzhe Zhang
- Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Feifei Liu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China; University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Limin Zeng
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China
| | - Runze Peng
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China; University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Li Yang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China
| | - Huazhou Ying
- Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wei Tang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China
| | - Wuhong Chen
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China
| | - Jianping Zuo
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China
| | - Xiankun Tong
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China.
| | - Tao Liu
- Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China.
| | - Youhong Hu
- Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai 201203, China.
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9
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Iron MA. Evaluation of the Factors Impacting the Accuracy of 13C NMR Chemical Shift Predictions using Density Functional Theory-The Advantage of Long-Range Corrected Functionals. J Chem Theory Comput 2017; 13:5798-5819. [PMID: 29016125 DOI: 10.1021/acs.jctc.7b00772] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The various factors influencing the accuracy of 13C NMR calculations using density functional theory (DFT), including the basis set, exchange-correlation (XC) functional, and isotropic shielding calculation method, are evaluated. A wide selection of XC functionals (over 70) were considered, and it was found that long-range corrected functionals offer a significant improvement over the other classes of functionals. Based on a thorough study, it is recommended that for calculating NMR chemical shifts (δ) one should use the CSGT method, the COSMO solvation model, and the LC-TPSSTPSS exchange-correlation functional in conjunction with the cc-pVTZ basis set. A selection of problems in natural product identification are considered in light of the newly recommended level of theory.
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Affiliation(s)
- Mark A Iron
- Computational Chemistry Unit, Department of Chemical Research Support, Weizmann Institute of Science , Rehovot 7610001, Israel
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10
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Liu XJ, Zhang HJ, Quan ZS. Synthesis and evaluation of the anticonvulsant activities of 2,3-dihydrophthalazine-1,4-dione derivatives. Med Chem Res 2017. [DOI: 10.1007/s00044-017-1896-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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11
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Substituted benzoquinazolinones. Part 1: Synthesis of 6-aminobenzo[h]quinazolinones via Buchwald–Hartwig amination from 6-bromobenzo[h]quinazolinones. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.05.117] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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12
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Verhelst T, Liu Z, Maes J, Maes BUW. Synthesis of (Hetero)arylated Pyridazin-3(2 H)-ones via Negishi Reaction Involving Zincated Pyridazin-3(2 H)-ones. J Org Chem 2011; 76:9648-59. [DOI: 10.1021/jo201587j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Tom Verhelst
- Organic Synthesis,
Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, B-2020
Antwerp, Belgium
| | - Zuming Liu
- Organic Synthesis,
Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, B-2020
Antwerp, Belgium
| | - Jens Maes
- Organic Synthesis,
Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, B-2020
Antwerp, Belgium
| | - Bert U. W. Maes
- Organic Synthesis,
Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, B-2020
Antwerp, Belgium
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Verhelst T, Maes J, Liu Z, Sergeyev S, Maes BUW. Synthesis of functionalized pyridazin-3(2H)-ones via selective bromine-magnesium exchange and lactam directed ortho C-H magnesiation. J Org Chem 2011; 76:6670-7. [PMID: 21732644 DOI: 10.1021/jo201009m] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Selective bromine-magnesium exchange on 2-benzyl-5-bromo-4-methoxypyridazin-3(2H)-one could be achieved when MesMgBr was used as reagent. With more nucleophilic RMgCl species (R = Bu, i-Pr, Ph) both nucleophilic addition-elimination at C-4 and bromine-magnesium exchange at C-5 occurred. In 2-benzyl-5-bromopyridazin-3(2H)-one, which does not contain a substituent at C-4, addition could not be suppressed. Less nucleophilic Mg amides (TMPMgCl·LiCl) allowed regioselective C-H magnesiation at the C-4 position in such substrates, as exemplified for 2-benzyl-5-chloro- and 2-benzyl-6-chloropyridazin-3(2H)-one. Quenching of the magnesiated pyridazinones with electrophiles gives access to a variety of hitherto unknown pyridazin-3(2H)-one derivatives.
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Affiliation(s)
- Tom Verhelst
- Organic Synthesis, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
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14
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Synthesis and reactions of some novel 4-biphenyl-4-(2H)-phthalazin-1-one derivatives with an expected antimicrobial activity. JOURNAL OF SAUDI CHEMICAL SOCIETY 2011. [DOI: 10.1016/j.jscs.2010.10.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Pattison G, Sandford G, Yufit DS, Howard JAK, Christopher JA, Miller DD. Polysubstituted Pyridazinones from Sequential Nucleophilic Substitution Reactions of Tetrafluoropyridazine. J Org Chem 2009; 74:5533-40. [DOI: 10.1021/jo9006943] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | | | | | | | - John A. Christopher
- GlaxoSmithKline R&D, Medicines Research Centre, Gunnels Wood Road, Stevenage, Hertfordshire SG1 2NY, U.K
| | - David D. Miller
- GlaxoSmithKline R&D, Medicines Research Centre, Gunnels Wood Road, Stevenage, Hertfordshire SG1 2NY, U.K
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Timmons C, Wipf P. Density Functional Theory Calculation of 13C NMR Shifts of Diazaphenanthrene Alkaloids: Reinvestigation of the Structure of Samoquasine A. J Org Chem 2008; 73:9168-70. [DOI: 10.1021/jo801735e] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Cody Timmons
- Department of Chemistry and Physics, Southwestern Oklahoma State University, Weatherford, Oklahoma 73096 USA; Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
| | - Peter Wipf
- Department of Chemistry and Physics, Southwestern Oklahoma State University, Weatherford, Oklahoma 73096 USA; Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
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Latypov S, Balandina A, Boccalini M, Matteucci A, Usachev K, Chimichi S. Structure Determination of Regioisomeric Fused Heterocycles by the Combined Use of 2D NMR Experiments and GIAO DFT13C Chemical Shifts. European J Org Chem 2008. [DOI: 10.1002/ejoc.200800550] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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