Notes and references
‡A report of constituents of floral scents of Saponaria officinalis
suggested that benzylisocyanide was detected by GC-MS analysis;
however, it was not established whether this volatile is an air pollutant or
a plant metabolite.27
§Chemical structures of compounds are provided in the ESI.†
¶Isocyalexin A (4): HPLC: tR = 11.0 min. UV (CH3CN–H2O, HPLC)
λmax (nm): 220, 269. FTIR (KBr, cm−1) νmax: 3305, 3129, 2134, 1592,
1514, 1447, 1366, 1336, 1272, 1079. 1H NMR (500 MHz, CD3OD) δ
7.45 (1H, s), 7.10 (1H, dd, J = 8, 8 Hz), 6.97 (1H, d, J = 8 Hz), 6.58
(1H, d, 8 Hz), 3.91 (3H, s). 13C NMR δ (125.8 MHz, CD3OD) δ 164.1,
154.8, 137.3, 125.5, 124.3, 113.9, 106.4, 103.2, (JC-3-N = 15 Hz), 102.1,
56.0. HREI-MS m/z 172.0633 (M+), calcd for C10H8N2O 172.0632
(100%), 157.04 (69%), 129.04 (69%). HPLC-MS-ESI m/z [M − H]−,
171.1 (11%), 156.0 (100%).
k4-Methoxyindole-3-carbonitrile does not appear to have been
described previously, synthesis and spectroscopic data are provided in
ESI.†
**Thioglucosyl hydrolases (EC 3.2.1.147) are commonly known as
myrosinases.
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in other Brassica species and its potential synergistic activity in
naturally occurring blends of cruciferous phytoalexins.
Considering the novel chemical structure and its selective anti-
fungal activity, phytoalexin 4 is a new but prominent jigsaw
piece yet to find a position in the biosynthetic puzzle of crucifer-
ous phytoalexins. Unquestionably, the importance of cruciferous
phytoalexins would warrant further chemical and biochemical
work to solve the puzzle.
Acknowledgements
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Department of Chemistry for NMR data. Financial support for
the authors’ work was obtained from the Natural Sciences and
Engineering Research Council of Canada (Discovery Grant to
M. S. C. P.), Canada Foundation for Innovation, the Saskatche-
wan Government, and the University of Saskatchewan (scholar-
ship to E. E. Y.).
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3616 | Org. Biomol. Chem., 2012, 10, 3613–3616
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