BULLETIN OF THE
Article
Phoyunbenes A-D and Thunalbene
KOREAN CHEMICAL SOCIETY
3.89 (3H, s), 3.84 (3H, s); 13C NMR (75 MHz, CDCl3) δ
160.6, 159.6, 153.3, 151.7, 140.8, 139.7, 134.1, 133.0,
127.6, 124.0, 123.3, 120.7, 117.7, 117.5, 107.5, 105.0,
104.5, 100.1, 74.2, 68.8, 61.4, 56.0, 55.3.
General Procedure for Allyl Deprotection of Stilbenes. To
a mixture of allyl protected stilbene (28–32) (0.2 mmol,
1 equiv) and K2CO3 (1.0 mmol, 5.0 equiv) in anhydrous
MeOH (3 mL) was added Pd(PPh3)4 (0.002 mmol,
0.01 equiv) under nitrogen atmꢀosphere at room temperature.
The mixture was stirred at 60 C for 6 h. After completion
of the reaction, cooled to room temperature and then it was
quenched with a solution of 1 N HCl (1.5 mL). The aqueous
solution was extracted with EtOAc (3 × 25 mL), the com-
bined organic layer was washed with brine (2 × 30 mL), dried
over anhydrous Na2SO4, filtered and the filtrate was concen-
trated in vacuo. The crude was purified by column chromatog-
raphy (EtOAc/hexane = 1/2) to yield the natural stilbene
(1–5) [note: in case of 2 allyl groups deprotection, 10 equiv
of K2CO3 employed].
Trans-3,40-(diallyoxy)-20,30,5-trimethoxystilbene (29):
Yield: 95%; Rf = 0.88 (EtOAc/hexane = 1/2); pale yellow
1
color liquid; H NMR (300 MHz, CDCl3) δ 7.26 (1H, d,
J = 16.5 Hz), 7.22 (1H, d, J = 8.4 Hz), 6.89 (1H, d,
J = 16.5 Hz), 6.64 (1H, d, J = 8.4 Hz), 6.62 (2H, br d,
J = 1.8 Hz), 6.35 (1H, t, J = 1.8 Hz), 6.09–5.97 (2H, m),
5.39 (2H, dd, J = 17.1, 1.5 Hz), 5.26 (2H, dd, J = 10.8,
1.5 Hz), 4.55 (2H, dt, J = 5.1, 1.5 Hz), 4.51 (2H, dt,
J = 5.1, 1.5 Hz), 3.86 (6H, s), 3.78 (3H, s); 13C NMR
(75 MHz, CDCl3) δ 160.6, 159.6, 155.3, 152.1, 151.6,
142.5, 139.7, 133.0, 132.9, 127.7, 124.2, 123.3, 120.5,
117.6, 109.2, 105.0, 104.6, 100.9, 69.6, 68.8, 61.5, 60.9, 55.4.
Phoyunbene A (1): Yield: 67%; Rf = 0.64 (EtOAc/hex-
Trans-3,30-(diallyloxy)-2,50-dimethoxystilbene
(30):
ane = 1/1); white solid; mp 168–170 C; 1H NMR
ꢀ
Yield: 96%; Rf = 0.63 (EtOAc/hexane = 1/4); pale yellow
color liquid; H NMR (300 MHz, CDCl3) δ 7.40 (1H, d,
(300 MHz, CDCl3) δ 7.24 (1H, d, J = 16.2 Hz), 7.08 (1H,
d, J = 8.7 Hz), 6.95 (1H, d, J = 16.2 Hz), 6.72 (1H, d,
J = 8.7 Hz), 6.56 (1H, s), 6.54 (1H, s), 6.26 (1H, t,
J = 2.7 Hz), 3.85 (3H, s), 3.81 (3H, s), 3.77 (3H, s); 13C
NMR (75 MHz, CDCl3) δ 162.3, 159.5, 149.6, 147.0,
141.3, 140.4, 128.7, 125.1, 124.0, 117.0, 108.6, 106.3,
104.6, 101.3, 61.2, 56.6, 55.6; EI-MS: m/z 302 (M+, base),
272, 227.
1
J = 16.8 Hz), 7.21 (1H, dd, J = 7.8, 1.5 Hz), 7.02 (1H, d,
J = 16.8 Hz), 7.00 (1H, t, J = 7.8 Hz), 6.81 (1H, dd,
J = 7.8, 1.5 Hz), 6.70 (1H, br d, J = 2.1 Hz), 6.68 (1H, br
d, J = 2.1 Hz), 6.40 (1H, t, J = 2.1 Hz), 6.13–6.00 (2H,
m), 5.43 (2H, dd, J = 17.1, 0.9 Hz), 5.29 (1H, dd, J = 10.8,
1.5 Hz), 5.28 (1H, dd, J = 10.8, 1.5 Hz), 4.58 (2H, dt,
J = 5.4, 1.5 Hz), 4.55 (2H, dt, J = 5.4, 1.5 Hz), 3.86 (3H,
s), 3.81 (3H, s); 13C NMR (75 MHz, CDCl3) δ 160.7,
159.7, 151.8, 147.2, 139.5, 133.1, 133.0, 131.3, 129.7,
123.8, 123.4, 118.1, 117.7, 117.3, 113.2, 105.4, 104.9,
100.5, 69.5, 68.9, 61.0, 55.4.
Phoyunbene B (2): Yield: 69%; Rf = 0.61 (EtOAc/hex-
1
ane = 1/1); colorless liquid; H NMR (300 MHz, CDCl3) δ
7.26 (1H, d, J = 16.2 Hz), 7.25 (1H, d, J = 8.7 Hz), 6.90
(1H, d, J = 16.2 Hz), 6.74 (1H, d, J = 8.7 Hz), 6.63 (2H,
s), 6.33 (1H, s), 5.85 (1H, br s), 5.50 (1H, br s), 3.96 (3H,
s), 3.88 (3H, s), 3.82 (3H, s); 13C NMR (75 MHz, CDCl3) δ
160.8, 156.8, 150.4, 149.2, 140.1, 139.7, 127.2, 123.5,
123.2, 121.2, 110.9, 105.6, 104.7, 100.4, 61.0, 55.4, 55.3;
EI-MS: m/z 302 (M+, base), 255, 227.
Trans-3-(allyloxy)-20,30,5-trimethoxystilbene
(31):
Yield: 98%; Rf = 0.44 (EtOAc/hexane = 1/4); pale yellow
1
color liquid; H NMR (300 MHz, CDCl3) δ 7.44 (1H, d,
J = 16.2 Hz), 7.25 (1H, dd, J = 7.8, 1.5 Hz), 7.07 (1H, t,
J = 7.8 Hz), 7.06 (1H, d, J = 16.2 Hz), 6.86 (1H, dd,
J = 7.8, 1.5 Hz), 6.75 (1H, br d, J = 2.1 Hz), 6.72 (1H, br
d, J = 2.1 Hz), 6.44 (1H, t, J = 2.1 Hz), 6.16–6.03 (1H,
m), 5.47 (1H, dd, J = 17.1, 1.5 Hz), 5.33 (1H, dd, J = 10.5,
1.5 Hz), 4.59 (2H, dt, J = 5.4, 1.5 Hz), 3.90 (3H, s), 3.87
(3H, s), 3.86 (3H, s); 13C NMR (75 MHz, CDCl3) δ 160.7,
159.7, 152.9, 146.8, 139.5, 133.0, 131.2, 129.7, 124.0,
123.3, 117.8, 111.3, 105.4, 104.9, 100.5, 68.9, 61.1,
55.8, 55.4.
Phoyunbene C (3): Yield: 68%; Rf = 0.50 (EtOAc/hex-
1
ane = 1/1); colorless liquid; H NMR (300 MHz, CDCl3) δ
7.24 (1H, d, J = 16.8 Hz), 7.10 (1H, dd, J = 7.8, 1.2 Hz),
7.01 (1H, d, J = 16.8 Hz), 6.99 (1H, t, J = 7.8 Hz), 6.88
(1H, dd, J = 7.8, 1.2 Hz), 6.64 (2H, br t, J = 1.8 Hz), 6.35
(1H, t, J = 1.8 Hz), 5.81 (1H, br s), 5.60 (1H, br s). 3.84
(3H, s), 3.83 (3H, s); 13C NMR (75 MHz, CDCl3) δ 160.9,
156.9, 148.9, 144.7, 139.6, 130.3, 130.0, 124.9, 123.1,
118.0, 114.8, 105.9, 105.1, 101.0, 61.9, 55.4; EI-MS: m/z
272 (M+, base), 240, 197.
Trans-3,30-(diallyloxy)-5’-methoxystilbene (32): Yield:
98%; Rf = 0.66 (EtOAc/hexane = 1/4); pale yellow color liq-
uid; 1H NMR (300 MHz, CDCl3) δ 7.28 (1H, t, J = 7.8 Hz),
7.12(1H, d, J = 7.8 Hz), 7.08(1H, t, J = 1.8 Hz), 7.07(1H, d,
J = 16.2 Hz), 7.01 (1H, d, J = 16.2 Hz), 6.85 (1H, dd,
J = 7.8, 1.8 Hz), 6.71 (1H, br d, J = 1.8 Hz), 6.68 (1H,
br d, J = 1.8 Hz), 6.44 (1H, t, J = 1.8 Hz), 6.16–6.03
(2H, m), 5.46 (2H, dd, J = 16.2, 0.9 Hz), 5.33 (2H, dd,
J = 10.5, 0.9 Hz), 4.59 (4H, dt, J = 4.8, 0.9 Hz), 3.85 (3H,
s); 13C NMR (75 MHz, CDCl3) δ 160.7, 159.7, 158.7,
139.0, 138.4, 133.1, 133.0, 129.5, 128.9, 128.8, 119.4,
117.7, 117.6, 114.1, 112.5, 105.2, 104.7, 100.7, 68.9,
68.8, 55.4.
Phoyunbene D (4): Yield: 79%; Rf = 0.64 (EtOAc/hex-
1
ane = 1/1); pale yellow color liquid; H NMR (300 MHz,
CDCl3) δ 7.41 (1H, d, J = 16.5 Hz), 7.23 (1H, d,
J = 7.8 Hz), 7.07 (1H, t, J = 7.8 Hz), 7.02 (1H, d,
J = 16.5 Hz), , 6.86 (1H, d, J = 7.8 Hz), 6.70 (1H, s), 6.67
(1H, s), 6.39 (1H, t, J = 1.8 Hz), 3.89 (3H, s), 3.87 (3H, s),
3.80 (3H, s); 13C NMR (75 MHz, CDCl3) δ 160.7, 156.9,
152.7, 146.4, 139.6, 131.1, 129.6, 124.2, 123.1, 117.8,
111.3, 105.9, 105.0, 100.9, 61.1, 55.7, 55.3; EI-MS: m/z
286 (M+), 254 (base), 211.
Thunalbene (5): Yield: 68%; Rf = 0.62 (EtOAc/hexane =
1/1); pale yellow color liquid; 1H NMR (300 MHz, CDCl3) δ
Bull. Korean Chem. Soc. 2015, Vol. 36, 2907–2914
© 2015 Korean Chemical Society, Seoul & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim