Research Article
Formation of 5-Hydroxy-3-methoxy-1,4-naphthoquinone and 8-Hydroxy-4-methoxy-1,2-naphthoquinone from Juglone
Table 3
DFT-calculated 13C NMR chemical shifts (ppm) for compounds 2, 3, 6, 8, 11, and 12.
| Compound | C-1 | C-2 | C-3 | C-4 | C-4a | C-5 | C-6 | C-7 | C-8 | C-8a | CH3 |
| 2-Hydroxy juglone (2) | 181.93 | 156.99 | 107.41 | 190.08 | 112.87 | 163.49 | 127.36 | 133.75 | 118.07 | 129.19 | ā | 3-Hydroxy juglone (11) | 181.77 | 108.35 | 156.87 | 185.51 | 111.33 | 163.53 | 121.69 | 138.31 | 118.51 | 132.99 | ā | 2-Hydroxy-7-methyl juglone (3) | 182.16 | 156.97 | 107.50 | 189.51 | 110.56 | 163.81 | 126.85 | 147.59 | 118.88 | 128.95 | 19.63 | 3-Hydroxy-7-methyl juglone (8) | 182.07 | 108.00 | 157.30 | 184.36 | 109.37 | 163.93 | 121.10 | 152.92 | 119.59 | 133.35 | 20.78 | 2-Methoxy juglone (12) | 178.88 | 162.04 | 106.98 | 189.90 | 112.93 | 163.45 | 124.69 | 134.41 | 117.97 | 131.52 | 51.86 | 3-Methoxy juglone (6) | 181.91 | 107.32 | 161.80 | 184.56 | 112.91 | 163.95 | 122.57 | 136.40 | 117.42 | 131.94 | 51.74 | 6, observed (this work) | 183.95 | 110.50 | 160.08 | 184.94 | 114.28 | 161.98 | 123.87 | 137.20 | 118.95 | 132.06 | 56.61 |
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