Structure Elucidation of Prenyl- and Geranyl-Substituted Coumarins in Gerbera piloselloides by NMR Spectroscopy, Electronic Circular Dichroism Calculations, and Single Crystal X-ray Crystallography
Abstract
:1. Introduction
2. Results
Structure Elucidation of Prenyl- and Geranyl Coumarin Derivatives
3. Materials and Methods
3.1. Plant Material and Extraction Procedure
3.2. Chemicals and Reagents
3.3. LC-PDA-HRMS
3.4. Dual High-Resolution PTP1B/α-Glucosidase Inhibition Profiling
3.5. Targeted Isolation of PTP1B/α-Glucosidase Inhibitors and Major Metabolites
3.6. Chiral Separation of Enantiomers
3.7. ECD Data Acquisition and Calculations
3.8. NMR Experiments
3.9. X-ray Crystallographic Analysis of 19
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Sample Availability: Not available. |
Pos. | δH (J, in Hz) | Pos. | δH (J, in Hz) | ||
---|---|---|---|---|---|
2 | 6 | 10 | 5 | ||
6 | 7.12, d (7.4 Hz) | 7.26, d (8.4 Hz) | 6.99, d (7.5 Hz) | 3 | 5.76, d (9.8 Hz) |
7 | 7.45, dd (8.3, 7.4 Hz) | 7.56, dd (8.4, 7.5 Hz) | 7.29, dd (8.3, 7.5 Hz) | 4 | 6.42, d (9.8 Hz) |
8 | 7.19, d (8.3 Hz) | 7.20, d (7.5 Hz) | 7.03, d (8.3 Hz) | 5 | 7.56, d (2.1 Hz) |
9 | 4.58, d (4.1 Hz) | 5.51, d (7.6 Hz) | 3.83, d (10.5 Hz) | 7 | 7.70, d (2.1 Hz) |
10 | 3.75, d (4.1 Hz) | 4.78, d (7.6 Hz) | 5.32, br s | 10 | 2.52, s |
11 | 11 | 1.46, s | |||
12 | 2.72, s | 1.98, ddd (14, 13.0, 3.3 Hz); 1.80, m | 2.25, m2.02, m | 12 | 1.47, s |
13 | 1.52, s | 2.00, m; 1.68, m | 1.77, m | 1′ | 2.95, dd (13.3, 5.5 Hz); 2.68, dd (13.4, 7.8 Hz) |
14 | 1.57, s | 3.52, d (10.0 Hz) | 2.96, br s | 2′ | 4.31, dd (7.4, 5.7 Hz) |
16 | 4.73b; 4.81b | 4.52, s; 4.54, s | 4′ | 4.76b; 4.83 b | |
17 | 1.66, s | 1.68, s | 5′ | 1.81, s | |
18 | 2.72, s | 2.76, s | |||
19 | 1.58, s | 1.70, s |
Pos. | δC | Pos. | δC | |||||||
---|---|---|---|---|---|---|---|---|---|---|
2 | 6 | 10 | 11 | 14 | 15 | 17 | 23 | 5 | ||
2 | 164.7 | 161.4 | 165.5 | 162.6 | 164.1 | 162.7 | 163.9 | 165.2 | 2 | 78.9 |
3 | 101.8 | 102.7 | 106.4 | 100.5 | 102.9 | 99.7 | 102.9 | 103.9 | 3 | 132.0 |
4 | 163.7 | 171.1 | 171.4 | 182.2 | 162.4 | 181.8 | 163.5 | 163.6 | 4 | 122.8 |
4a | 115.5 | 112.2 | 118.6 | 122.3 | 120 | 121 | 116.1 | 116.1 | 4a | 121.7 |
5 | 139.0 | 138.5 | 138.8 | 133.0 | 138.0 | 141.3 | 138.2 | 138.1 | 5 | 126.4 |
6 | 128.9 | 115.5 | 127.6 | 133.1 | 128.2 | 128.9 | 128.7 | 128.9 | 6 | 130.7 |
7 | 132.8 | 133.8 | 130.7 | 128.9 | 131.6 | 133.0 | 132.0 | 132.1 | 7 | 133.1 |
8 | 115.9 | 127.5 | 115.1 | 116.2 | 115.4 | 116.3 | 115.7 | 115.9 | 8 | 127.7 |
8a | 155.5 | 157.9 | 155.2 | 155.7 | 154.9 | 155.8 | 155.0 | 155.0 | 8a | 156.8 |
9 | 66.5 | 76.1 | 37.3 | 31.1 | 31.7 | 33.7 | 34.1 | 37.4 | 9 | 199.6 |
10 | 73.8 | 95.9 | 126.0 | 121.7 | 121.0 | 123.1 | 122.8 | 38.4 | 10 | 26.1 |
11 | 83.1 | 74.0 | 135.5 | 135.4 | 135.2 | 134.7 | 135.2 | 88.2 | 11 | 28.6 |
12 | 23.3 | 36.1 | 31.4 | 30.5 | 30.3 | 32.2 | 32.0 | 40.6 | 12 | 28.6 |
13 | 24.4 | 29.9 | 30.3 | 21.4 | 21.2 | 25.4 | 25.5 | 26.6 | 1′ | 36.8 |
14 | 22.9 | 78.3 | 45.4 | 41.0 | 40.3 | 47.1 | 46.2 | 48 | 2′ | 75.8 |
15 | 147.5 | 150 | 84.8 | 83.6 | 86.4 | 86.3 | 40.4 | 3′ | 148.6 | |
16 | 111.0 | 110.6 | 22.4 | 23.3 | 22.6 | 23.9 | 23.4 | 4′ | 111.1 | |
17 | 19.5 | 19.2 | 23.4 | 23.4 | 23.3 | 23.4 | 27.6 | 5′ | 17.7 | |
18 | 21.1 | 23.2 | 25.5 | 25.6 | 27.1 | 27.3 | 34.1 | |||
19 | 30.8 | 23.4 | 25.4 | 25.0 | 20.1 | 20.3 | 17.9 |
Pos. | 11 | 14 | 15 | 17 | 23 |
---|---|---|---|---|---|
6 | 7.13, d (7.3 Hz) | 7.08, d (7.4 Hz) | 7.14, d (7.5 Hz) | 7.08, d (7.5 Hz) | 7.11, d (7.5 Hz) |
7 | 7.47, dd (8.3, 7.3 Hz) | 7.39, dd (8.2, 7.4 Hz) | 7.48, dd (8.3, 7.5 Hz) | 7.39, dd (8.3, 7.5 Hz) | 7.41, dd (8.4, 7.5 Hz) |
8 | 7.22, d (8.3 Hz) | 7.13, d (8.2 Hz) | 7.23, d (8.3 Hz) | 7.13, d (8.3 Hz) | 7.16, d (8.3 Hz) |
9 | 3.51, dd (6.7, 4.0 Hz) | 3.42, dd (6.8, 5.4 Hz) | 3.21, d (10.8 Hz) | 3.11, d (10.9 Hz) | 3.01, d (9.4 Hz) |
10 | 6.25, br s | 6.18, br s | 6.24, m | 6.24, m | 2.72 (m) |
12 | 2.02, m; 1.98, m | 2.06, m; 1.98, m | 2.19, br s | 2.19, m | 1.91, dd (13.0, 7.5 Hz); 2.07, dd (12.8, 7.5 Hz) |
13 | 2.04, m; 1.38, m | 2.02, m; 1.34, m | 1.96, m; 1.49, m | 1.98, m; 1.47, m | 1.76, dd (14.0, 7.5 Hz); 1.73, m |
14 | 1.88, ddd (11.5, 6.1, 3.0 Hz) | 1.88, ddd (11.8, 6.3, 3.0 Hz) | 1.7, ddd (13.0, 10.8, 2.1 Hz) | 1.71, ddd (12.7, 11.0, 2.0 Hz) | 2.50, dd (8.1, 7.0 Hz) |
16 | 2.80, s | 2.69, s | 2.81, s | 2.70, s | 2.74, s |
17 | 1.67, s | 1.68, s | 1.68, s | 1.68, s | 1.56, s |
18 | 1.51, s | 1.57, s | 1.54, s | 1.61, s | 1.40, s |
19 | 1.42, s | 1.41, s | 1.26, s | 1.26, s | 0.88, s |
Pos. | δC | Pos. | δC | ||||||
---|---|---|---|---|---|---|---|---|---|
18 | 19 | 24 | 25 | 18 | 19 | 24 | 25 | ||
2 | 163.5 | 163.3 | 163.9 | 163.0 | 2′ | 165.0 | 163.8 | 163.5 | 163.4 |
3 | 103.0 | 99.6 | 99.2 | 102.6 | 3′ | 101.3 | 104.9 | 109.0 | 109.0 |
4 | 167.5 | 181.7 | 181.9 | 164.2 | 4′ | 164.0 | 166.3 | 163.1 | 163.0 |
4a | 115.1 | 121.5 | 122.2 | 115.8 | 4a′ | 115.7 | 115.4 | 116.0 | 115.6 |
5 | 138.3 | 141.2 | 141.3 | 138.3 | 5′ | 138.0 | 138.3 | 138.3 | 138.3 |
6 | 128.7 | 128.7 | 128.6 | 128-7 | 6′ | 128.5 | 128.5 | 128.4 | 128.8 |
7 | 132.4 | 133.0 | 131.9 | 132.1 | 7′ | 131.9 | 132.0 | 132.7 | 132.2 |
8 | 115.6 | 116.4 | 115.4 | 115.6 | 8′ | 115.3 | 115.9 | 115.9 | 115.8 |
8a | 154.9 | 155.8 | 155.7 | 155.1 | 8a′ | 154.7 | 155.1 | 155.1 | 155.2 |
9 | 28.8 | 26.2 | 25.9 | 26.4 | 9′ | 28.9 | 28.8 | 26.5 | 26.7 |
10 | 52.9 | 45.0 | 54.1 | 53.1 | 10′ | 38.2 | 31.9 | 30.2 | 30.5 |
11 | 81.4 | 86.3 | 86.4 | 85.0 | 11′ | 83.3 | 80.8 | 81.0 | 81.5 |
12 | 23.5 | 22.4 | 22.3 | 23.9 | 12′ | 23.6 | 23.6 | 23.4 | 23.7 |
13 | 26.8 | 24.9 | 28.3 | 28.9 | 13′ | 43.2 | 40.3 | 40.1 | 40.8 |
14 | 19.7 | 28.9 | 20.5 | 21.2 | 14′ | 27.8 | 28.3 | 28.9 | 29.3 |
Pos. | δH (J, in Hz) | |||
---|---|---|---|---|
18 | 19 | 24 | 25 | |
6 | 7.16, d (7.4 Hz) | 7.13, d (7.3 Hz) | 7.13, d (7.5 Hz) | 7.07, d (7.5 Hz) |
7 | 7.46, dd (8.2, 7.4 Hz) | 7.48, dd (8.2, 7.3 Hz) | 7.40, dd (8.2, 7.5 Hz) | 7.38, dd (8.0, 7.5 Hz) |
8 | 7.19, d (8.2 Hz) | 7.24, d (8.0 Hz) | 7.15, d (8.2 Hz) | 7.11, d (8.0 Hz) |
9 | 2.68, td (12.0, 4.2 Hz) | 3.10, br dt (13.1, 6.3 Hz) | 2.72, td (12.7, 4.2 Hz) | 2.68, td (12.6, 4.2 Hz) |
10 | 2.17, dd (12.0, 1.9 Hz) | 2.15, br d (6.6 Hz) | 1.62, dd (12.4, 3.2 Hz) | 1.62, dd (12.4, 3.1 Hz) |
12 | 2.70, s | 2.76, s | 2.78, s | 2.69, s |
13 | 1.91, s | 1.67, s | 1.79, s | 1.87, s |
14 | 1.10, s | 1.77, s | 1.43, s | 1.44, s |
6′ | 7.09, d (7.4 Hz) | 7.15, d (7.5 Hz) | 7.09, d (7.6 Hz) | 7.10, d (7.8 Hz) |
7′ | 7.39, dd (8.4, 7.4 Hz) | 7.44, dd (8.3, 7.5 Hz) | 7.46, dd (8.4, 7.6 Hz) | 7.41, dd (8.3, 7.8 Hz) |
8′ | 7.12, d (8.4 Hz) | 7.17, d (8.3 Hz) | 7.21, d (8.4 Hz) | 7.15, d (8.3 Hz) |
9′ | 3.59, q (2.7 Hz) | 3.50, br q | 3.08, q (3.2 Hz) | 3.13, q (3.1 Hz) |
10′ | 2.22, dd (13.2, 2.8 Hz) 1.90, dt (13.2, 2.8 Hz) | 2.31, dd (14.1, 2.8 Hz); 1.82, dt (14.1, 2.5 Hz) | 2.29, dd (14.0, 3.4 Hz); 1.53, dd (14.0, 2.6 Hz) | 2.28, dd (13.9, 3.4 Hz); 1.55, dd (13.9, 2.7 Hz) |
12′ | 2.81, s | 2.84, s | 2.73, s | 2.74, s |
13′ | 3.51, ddd (14.0, 4.2, 2.6 Hz); 1.47, dd (14.0, 12.0 Hz) | 3.02, ddd (14.2, 5.5, 2.5 Hz); 1.71, dd (14.2, 13.1 Hz) | 3.80, dd (14.7, 4.2 Hz); 1.40 dd (14.7, 13.1 Hz) | 3.68, dd (14.8, 4.3 Hz); 1.48, dd (14.8, 13.0 Hz) |
14′ | 1.61, s | 1.61, s | 1.78, s | 1.76, s |
Compound | α-Glucosidase (μM) | PTP1B (μM) |
---|---|---|
17 | 32% (201.6) | N.D.a |
18 | 40% (159.1) | N.D.a |
19 | 48% (129.1) | 67% (64.4) |
24 | 51% (129.1) | 47% (32.2) |
25 | 45% (64.4) | 32% (129.1) |
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Li, T.; Ma, X.; Fedotov, D.; Kjaerulff, L.; Frydenvang, K.; Coriani, S.; Hansen, P.R.; Kongstad, K.T.; Staerk, D. Structure Elucidation of Prenyl- and Geranyl-Substituted Coumarins in Gerbera piloselloides by NMR Spectroscopy, Electronic Circular Dichroism Calculations, and Single Crystal X-ray Crystallography. Molecules 2020, 25, 1706. https://doi.org/10.3390/molecules25071706
Li T, Ma X, Fedotov D, Kjaerulff L, Frydenvang K, Coriani S, Hansen PR, Kongstad KT, Staerk D. Structure Elucidation of Prenyl- and Geranyl-Substituted Coumarins in Gerbera piloselloides by NMR Spectroscopy, Electronic Circular Dichroism Calculations, and Single Crystal X-ray Crystallography. Molecules. 2020; 25(7):1706. https://doi.org/10.3390/molecules25071706
Chicago/Turabian StyleLi, Tuo, Xue Ma, Daniil Fedotov, Louise Kjaerulff, Karla Frydenvang, Sonia Coriani, Paul Robert Hansen, Kenneth T. Kongstad, and Dan Staerk. 2020. "Structure Elucidation of Prenyl- and Geranyl-Substituted Coumarins in Gerbera piloselloides by NMR Spectroscopy, Electronic Circular Dichroism Calculations, and Single Crystal X-ray Crystallography" Molecules 25, no. 7: 1706. https://doi.org/10.3390/molecules25071706