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Procházková E, Kucherak O, Stodůlková E, Tošner Z, Císařová I, Flieger M, Kolařík M, Baszczyňski O. NMR Structure Elucidation of Naphthoquinones from Quambalaria cyanescens. JOURNAL OF NATURAL PRODUCTS 2021; 84:46-55. [PMID: 33342211 DOI: 10.1021/acs.jnatprod.0c00930] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Naphthoquinones isolated from Quambalaria cyanescens (quambalarines) are natural pigments possessing significant cytotoxic and antimicrobial properties. Determining the structure of naphthoquinone compounds is important for the understanding of their biological activities and the informed synthesis of related analogues. Identifying quambalarines is challenging, because they contain a hydroxylated naphthoquinone scaffold and have limited solubility. Here, we report a detailed structural study of quambalarine derivatives, which form strong intramolecular hydrogen bonds (IMHBs) that enable the formation of several tautomers; these tautomers may complicate structural investigation due to their fast interconversion. To investigate tautomeric equilibria and identify new quambalarines, we complemented the experimental NMR spectroscopy data with density functional theory (DFT) calculations.
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Affiliation(s)
- Eliška Procházková
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 166 10 Prague, Czech Republic
| | - Oleksandr Kucherak
- Faculty of Science, Charles University, Hlavova 2030/8, 128 43 Prague, Czech Republic
| | - Eva Stodůlková
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic
| | - Zdeněk Tošner
- Faculty of Science, Charles University, Hlavova 2030/8, 128 43 Prague, Czech Republic
| | - Ivana Císařová
- Faculty of Science, Charles University, Hlavova 2030/8, 128 43 Prague, Czech Republic
| | - Miroslav Flieger
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic
| | - Miroslav Kolařík
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic
| | - Ondřej Baszczyňski
- Faculty of Science, Charles University, Hlavova 2030/8, 128 43 Prague, Czech Republic
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Dračínský M, Šála M, Klepetářová B, Šebera J, Fukal J, Holečková V, Tanaka Y, Nencka R, Sychrovský V. Benchmark Theoretical and Experimental Study on 15N NMR Shifts of Oxidatively Damaged Guanine. J Phys Chem B 2016; 120:915-25. [DOI: 10.1021/acs.jpcb.5b11428] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Martin Dračínský
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic v.v.i., Flemingovo náměstí 2, 16610 Praha, Czech Republic
| | - Michal Šála
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic v.v.i., Flemingovo náměstí 2, 16610 Praha, Czech Republic
| | - Blanka Klepetářová
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic v.v.i., Flemingovo náměstí 2, 16610 Praha, Czech Republic
| | - Jakub Šebera
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic v.v.i., Flemingovo náměstí 2, 16610 Praha, Czech Republic
- Institute
of Physics, Academy of Sciences of the Czech Republic, v.v.i, Na Slovance
2, CZ-182 21 Prague
8, Czech Republic
| | - Jiří Fukal
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic v.v.i., Flemingovo náměstí 2, 16610 Praha, Czech Republic
| | - Veronika Holečková
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic v.v.i., Flemingovo náměstí 2, 16610 Praha, Czech Republic
| | - Yoshiyuki Tanaka
- Faculty
of Pharmaceutical Sciences, Tokushima Bunri University, 180 Nishihama-Boji, Yamashirocho, Tokushima, Tokushima 980-8578, Japan
| | - Radim Nencka
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic v.v.i., Flemingovo náměstí 2, 16610 Praha, Czech Republic
| | - Vladimír Sychrovský
- Institute
of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic v.v.i., Flemingovo náměstí 2, 16610 Praha, Czech Republic
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Kadam SS, Maier L, Kostakis I, Pouli N, Toušek J, Nečas M, Marakos P, Marek R. Synthesis and Tautomerism of Substituted Pyrazolo[4,3-c]pyrazoles. European J Org Chem 2013. [DOI: 10.1002/ejoc.201300606] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Marshall P, Jenkins RL, Clegg W, Harrington RW, Callear SK, Coles SJ, Fallis IA, Dervisi A. Chiral Ag(i) and Pt(ii) complexes of ditopic NHC ligands: synthesis, structural and spectroscopic properties. Dalton Trans 2012; 41:12839-46. [DOI: 10.1039/c2dt31740k] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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