U. Warmers, W.A. Konig / Phytochemistry 52 (1999) 99±104
È
103
Dr. H. Muhle, Universitat Ulm, Germany. Plant
3.8. Mass spectrometry
samples are deposited at the herbarium of the Institut
fur Allgemeine Botanik, Universitat Hamburg,
Germany. Because of the greatly diering drying state
the fresh plant material was not weighed.
GC±MS measurements were carried out with a VG
Analytical 70±250S instrument and a HP 5890 gas
chromatograph.
3.9. ( )-cis-Cadina-1(6),4-diene (1)
3.2. Hydrodistillation
1H NMR (400 MHz, CDCl3): d 0.68 (3H, d, J = 6.6
Hz, H-12/13), 0.93 (3H, d, J=6.6 Hz, H-12/13), 1.03
(3H, d, J = 7.1 Hz, H-14), 1.40±1.68 (4H, m, H-8a,
H-8b, H-9a, H-9b), 1.79 (3H, s, H-13), 1.88±2.22 (7H,
m, H-2a, H-2b, H-3a, H-3b, H-7, H-10, H-11), 5.62
(1H, s, H-5); 13C NMR (125 MHz, CDCl3): d 17.1 (q,
C-12/13), 19.0 (t, C-8/9), 20.4 (q, C-14), 21.3 (q, C-12/
13), 23.6 (q, C-15), 28.0 (t, C-8/9), 29.2 (t, C-2/3), 29.3
(d, C-11), 29.5 (t, C-2/3), 33.4 (d, C-10), 43.0 (d, C-7),
122.1 (d, C-5), 129.9 (s, C-1/4/6), 133.0 (s, C-1/4/6),
133.7 (s, C-1/4/6); MS (EI, 70 eV): m/z (rel. int.) 204
(52) [M+], 189 (16) [M+ ±CH3], 162 (19), 161 (100),
145 (6), 134 (12), 119 (16), 105 (24), 91 (11), 81 (19),
69 (5), 55 (6), 41 (11).
The essential oil was prepared by hydrodistillation
(2 h) of aqueous homogenates of fresh and green
plants using n-hexane as collection solvent.
3.3. Extraction
Samples of plant volatiles were prepared by extrac-
tion (48 h, 208C) of fresh and green plants with diethyl
ether or ethyl acetate.
3.4. Gas chromatography
Orion Micromat 412 double column instruments
with (a) 25 m fused silica capillaries with polysiloxane
CpSil 5 and polysiloxane CpSil 19 (Chrompack) and
(b) 25 m fused silica capillaries with heptakis(2,6-di-O-
methyl-3-O-pentyl)-b-cyclodextrin and heptakis(6-O-
tert-butyldimethylsilyl-2,3-di-O-methyl)-b-cyclodextrin
in OV 1701 (50%, w/w); split injection; ¯ame ioniz-
ation detection; carrier gas 0.5 bar H2.
3.10. Oxidation of ( )-cis-cadina-1(6),4-diene (1)
1 mg of 1 was kept in CHCl3 at room temp. for 7
days. The reaction product was identi®ed as (+)-cis-
calamenene (3) by GC±MS and by comparison with a
sample of both enantiomeric pairs of cis- and trans-
calamenene on diverse capillary GC columns with
cyclodextrin derivatives.
3.5. Isolation
3.11. (+)-trans-Dauca-4(11),8-diene (2)
The isolation was carried out using dierent pre-
parative GC columns.
1H NMR (400 MHz, C6D6): d 0.93 (3H, s, H-15),
1.30±1.42 (1H, m, H-3b), 1.43±1.54 (2H, m, H-2b, H-
3a), 1.70 (3H, s, H-12), 1.67±1.77 (1H, m, H-2a), 1.76
(3H, s, H-13), 1.81 (3H, s, H-14), 1.98±2.07 (1H, m,
H-10a), 2.03±2.14 (1H, m, H-7b), 2.18±2.29 (1H, m,
H-10b), 2.24±2.34 (1H, m, H-6a), 2.29±2.41 (1H, m,
H-6b), 2.35±2.44 (1H, m, H-5), 2.86 (1H, ddd,
J = 17.0, 6.1, 2.5 Hz, H-7a), 5.61 (1H, dd, J = 7.6,
1.0 Hz, H-9); 13C NMR (125 MHz, C6D6): d 17.4 (q,
C-15), 20.8 (q, C-13), 23.0 (q, C-12), 28.7 (q, C-14),
30.0 (t, C-6), 30.2 (t, C-7), 31.0 (t, C-10), 40.2 (t, C-2),
41.2 (t, C-3), 44.7 (s, C-1), 52.4 (d, C-5), 109.6 (s, C-
3.6. Preparative GC
Modi®ed Varian 1400 instrument, equipped with a
stainless steel column (1.85 m  4.3 mm) with 10%
polydimethylsiloxane SE 30 on Chromosorb W-HP, or
equipped with a stainless-steel column (1.85 m  4.3
mm) with 5% heptakis(2,6-di-O-methyl-3-O-pentyl)-b-
cyclodextrin/OV 1701 (1:1, w/w) on Chromosorb W-
HP, or equipped with a stainless-steel column (1.95
m  5.3 mm) with 2.5% heptakis(6-O-tert-butyldi-
methylsilyl-2,3-di-O-methyl)-b-cyclodextrin/SE 52 (1:1,
w/w) on Chromosorb G-HP; ¯ame ionization detec-
tion; helium as carrier gas at a ¯ow rate of 240 ml/min
(Hardt & Konig, 1994).
1
11), 124.2 (d, C-9), 136.1 (s, C-8), 139.0 (s, C-4); H
NMR (500 MHz, CDCl3): d 0.84 (3H, s, H-15), 1.23±
1.34 (1H, m, H-3), 1.36±1.47 (2H, m, H-2b, H-3), 1.62
(3H, s, H-12), 1.68 (3H, s, H-13), 1.72 (3H, s, H-14),
1.66±1.78 (2H, m, H-2a, H-6), 1.84 (1H, bt, J = 14.9
Hz, H-7b), 2.03 (1H, dt, J = 17.7, 3.8 Hz, H-10),
2.16±2.32 (3H, m, H-5, H-6, H-10), 2.66 (1H, ddd,
J = 17.0, 6.1, 2.5 Hz, H-7a), 5.45 (1H, dd, J = 7.6,
1.0 Hz, H-9); 13C NMR (125 MHz, CDCl3): d 17.4 (q,
C-15), 20.9 (q, C-13), 23.1 (q, C-12), 28.7 (q, C-14),
3.7. NMR spectroscopy
NMR measurements were carried out with a Bruker
WM 400- or a Bruker WM 500 instrument using TMS
as internal standard.