Journal of Natural Products
ARTICLE
30 min, after which the remaining thionyl chloride was distilled off. The
acid chloride was cooled in an ice bath and treated with concentrated
ammonia solution (3 mL, 25%). The resulting solid material was filtered
and washed with H2O containing a small percentage of EtOH. The
product was dried at room temperature on filtration paper, yielding the
pure (GC-MS) pentadecanamide (0.18 g, 90%): 1H NMR (400 MHz,
CDCl3) δ 0.87 (3H, t, J = 6.8, CH3), 1.24 (22H, m), 1.62 (2H, m, H-3),
2.21 (2H, t, J = 7.8, H-2), 5.45 (1H, s, NH), 5.82 (1H, s, NH); 13C NMR
(CDCl3, 100 MHz) δ 14.14 (C-15), 22.71 (C-14), 25.55 (C-3), 29.25
(C-4), 29.35 (C-5), 29.38 (C-12), 29.49 (CH2), 29.63 (CH2), 29.67
(CH2), 29.67 (CH2), 29.69 (CH2), 29.71 (CH2), 31.95 (C-13), 36.00
(C-2), 176.17 (C-1); EIMS m/z 241 (1, Mþ), 212 (2), 198 (3), 184 (2),
170 (2), 156 (3), 142 (3), 128 (5), 114 (5), 97 (7), 86 (8), 72 (36), 59
(100), 43 (35), 29 (8).
(10) Van Wyk, J. H.; Mouton, P. l. N. Amphib. Reptil. 1992, 13, 1–12.
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Dodecyl (Z)-9-hexadecenoate (47) was synthesized by reflux-
ing a mixture of (Z)-9-hexadecenoic acid (25.4 mg, 0.01 mmol),
dodecanol (18.4 mg, 0.01 mmol), and pTSA monohydrate (1 mg) in
benzene (20 mL) for 30 h.25 The product was washed twice with H2O
and dried, and the solvent was removed on a rotary evaporator to yield
practically pure (GC-MS) dodecyl (Z)-9-hexadecenoate in quantitative
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13
yield: C NMR (100 MHz, CDCl3) δ 14.13 (C-120), 14.15 (C-16),
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22.69 (C-15), 22.72 (C-110), 25.06 (C-3), 25.97 (C-30), 27.20 (C-11),
27.26 (C-8), 28.69 (C-20), 29.02 (C-4), 29.14 (CH2), 29.17 (CH2),
29.21 (CH2), 29.29 (CH2), 29.38 (CH2), 29.56 (CH2), 29.61
(CH2), 29.67 (CH2), 29.68 (CH2), 29.72 (CH2), 29.77 (CH2), 31.82
(C-100), 31.95 (C-14), 34.44 (C-2), 64.45 (C-10), 129.78 (C-9), 130.01
(C-10), 174.03 (C-1); EIMS m/z 422 (1, Mþ), 255 (8), 236 (40), 194
(14), 152 (31), 125 (19), 111 (43), 98 (57), 97 (77), 83 (85), 71 (60),
69 (95), 57 (90), 43 (79), 41 (57), 29 (24).
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’ ASSOCIATED CONTENT
S
Supporting Information. Mass spectrometric data of
b
identified constituents and spectroscopic data of synthesized
compounds. This material is available free of charge via the
’ AUTHOR INFORMATION
Corresponding Author
*E-mail: stefanlouw@gmail.com. Tel: þ2721-406-6453.
’ ACKNOWLEDGMENT
This research was supported by Stellenbosch University and
the National Research Foundation, Pretoria, South Africa. L.
Ruddock is thanked for the collection of secretions.
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