662 J ournal of Natural Products, 2004, Vol. 67, No. 4
Ishikawa et al.
60 (230-400 mesh ASTM; Merck) were used, while for TLC
H2-7), 5.38 (1H, dd, J ) 9.5, 8.1 Hz, H-2′), 6.76 (1H, dt, J )
8.2, 1.0 Hz, H-3′′), 6.93 (1H, dd, J ) 7.3, 1.0 Hz, H-5′′), 7.06
(1H, dt, J ) 7.5, 0.7 Hz, H-4), 7.13 (1H, d, J ) 7.5 Hz, H-6),
7.32 (1H, dif t, J ) 7.5 Hz, H-5), 7.35 (2H, t, J ) 7.9 Hz, H-3′′′,
H-5′′′), 7.36 (1H, d, J ) 7.5 Hz, H-3), 7.41 (1H, ddd, J ) 8.2,
7.3, 1.7 Hz, H-4′′), 7.47 (1H, tt, J ) 7.9, 1.4 Hz, H-4′′′), 7.68
(1H, dd, J ) 8.2, 1.7 Hz, H-2′′), 8.02 (1H, dd, J ) 7.9, 1.4 Hz,
H-2′′′); 13C NMR (CDCl3) δ 61.6 (C-7, C-6′), 70.2 (C-4′), 73.7
(C-2′), 74.8 (C-3′), 76.2 (C-5′), 99.4 (C-1′), 112.3 (C-1′′), 115.5
(C-6), 117.3 (C-5′′), 119.0 (C-3′′), 123.0 (C-4), 125.1 (C-2), 128.3
(C-3′′′), 129.2 (C-1′′′), 129.4 (C-3), 129.66 (C-2′′′), 129.72 (C-
2′′), 129.9 (C-2′′′), 133.2 (C-4′′′), 135.5 (C-4′′), 154.7 (C-1), 166.0
(C-7′′′), 170.0 (C-7′′); FABMS m/z 511 [M + H]+.
and preparative TLC silica gel GF254 (Merck) was used.
E xt r a ct ion a n d Isola t ion . The root bark (195 g) of H.
cochinchinensis was extracted in a Soxhlet apparatus using
hexane (Fr. H: 0.64 g), benzene (Fr. B: 2.74 g), chloroform
(Fr. C: 2.61 g), and methanol (Fr. M: 16.84 g) as previously
described.1 Similar treatment of the trunk bark (19.9 g) and
the leaves (9.5 g) except in the use of Et2O in place of benzene
as a solvent afforded Fr. H (0.07 g from the trunk bark; 0.13
g from the leaves), Fr. E (0.09 g from the trunk bark; 0.10 g
from the leaves), Fr. C (0.20 g from the trunk bark; 0.20 g
from the leaves), and Fr. M (1.54 g from the trunk bark; 1.92
g from the leaves). Each fraction was subjected to repeated
separation using column chromatography, flash chromatog-
raphy, and preparative TLC. The root bark from Fr. B gave
six components: benzoic acid (0.054 g, 0.028%), cochinolide1
(0.074 g, 0.038%), cochinchiside A (1) (0.017 g, 0.009%),
tremulacin (2) (0.412 g, 0.211%), tremuloidin (3) (0.003 g,
0.002%), and tremulacinol (4) (0.029 g, 0.015%). Among them
2 (0.442 g, 0.227%; total 0.854 g, 0.438%) and 4 (0.192 g,
0.099%; total 0.221 g, 0.114%) were additionally isolated from
Fr. C. From Fr. D more polar cochinolide â-glucopyranoside1
(0.637 g, 0.3265%) was isolated. On the other hand, from Fr.
C of the leaves cochinchiside B (5) (0.067 g, 0.0919%) was
obtained.
Red u ction of 2 w ith LiAlH4. A mixture of 2 (0.051 g, 9.7
× 10-5 mol) and LiAlH4 (0.037 g, 9.7 × 10-4 mol) in THF (3
mL) was stirred at room temperature for 7 h. After workup,
the crude product was purified by preparative TLC (CHCl3-
MeOH, 5:1) to give a colorless amorphous mass (0.013 g, 46%),
mp 180-185 °C, which was compared with commercially
20
available salicin: IR (Nujol) νmax 3344 cm-1; [R]589 -52.6° (c
2.9, H2O); 1H NMR (DMSO-d6) δ 3.15-3.19 (1H, m, H-4′), 3.27
(1H, t, J ) 3.1 Hz, H-6′), 3.28-3.33 (1H, m, H-5′), 3.48 (1H,
dd, J ) 11.9, 6.1 Hz, H-3′), 3.70 (1H, dd, J ) 12.2, 2.1 Hz,
H-2′), 4.46-4.63 (each 1H, d, J ) 14.3 Hz, H2-7), 4.77 (1H, d,
J ) 7.6 Hz, H-1′), 7.01 (1H, t, J ) 7.3 Hz, H-6), 7.09 (1H, dd,
J ) 7.3 Hz, H-4), 7.21 (1H, dt, J ) 8.2, 1.8 Hz, H-5), 7.36 (1H,
dd, J ) 7.6, 1.8 Hz, H-3).
Com p ou n d 1 (coch in ch isid e A): pale yellow amorphous
mass; IR (CHCl3) νmax 3498, 1723 cm-1; UV (MeOH) λmax (log
ꢀ) 222 (4.09), 273 nm (3.45); CD (c 1.9 × 10-5, MeOH) [θ]
Tr em u loid in (3): colorless powder, mp 162-168 °C (lit.6
mp 201-204 °C); 1H NMR (CDCl3) δ 3.50-3.52 (1H, m, H-5′),
3.69 (1H, t, J ) 9.4 Hz, H-4′′′), 3.83 (1H, d, J ) 11.8 Hz, H-6′),
3.85 (1H, t, J ) 9.4 Hz, H-3′), 3.93 (1H, dd, J ) 11.8, 3.8 Hz,
H-6′), 4.35, 4.65 (each 1H, d, J ) 12.9 Hz, H2-7), 5.20 (1H, d,
J ) 8.0 Hz, H-1′), 5.35 (1H, dd, J ) 9.4, 8.0 Hz, H-2′), 7.01
(1H, d, J ) 7.6 Hz, H-6), 7.03 (1H, t, J ) 7.6 Hz, H-4), 7.24
(1H, t, J ) 7.6 Hz, H-5), 7.27 (1H, d, J ) 7.6 Hz, H-3), 7.46
(1H, t, J ) 7.6 Hz, H-3′′), 7.59 (1H, t, J ) 7.6 Hz, H-4′′), 8.09
(1H, d, J ) 7.6 Hz, H-3′′); HRFABMS m/z 413.1221 [M + Na]+,
calcd for C20H22O8Na, 413.1212.
1
-18958 (216 nm); H and 13C NMR, see Table 1; HRFABMS
m/z 567.1276 [M + K]+, calcd for C27H28O11K, 567.1268.
Acetyla tion of 1. A mixture of 1 (0.005 g, 9.5 × 10-5 mol),
Ac2O (0.1 mL), and pyridine (0.1 mL) was stored at room
temperature overnight and then at 60 °C overnight. After
workup, the crude product was purified by preparative TLC
to afford the tetraacetate (1a ) as a yellow amorphous mass
(0.006 g, 99%): IR (CHCl3) νmax 1753 cm-1; UV (MeOH) λmax
(log ꢀ) 228 (4.82), 273 nm (4.21); CD (c 2.15 × 10-5, MeOH) [θ]
14814 (230 nm), -12012 (217); 1H NMR (CDCl3) δ 1.92, 1.95,
2.10, 2.12 (each 3H, s, Me), 3.95 (1H, m, H-5′), 4.21 (1H, dd, J
) 12.2, 2.4 Hz, H-6′), 4.32 (1H, dd, J ) 12.2, 5.4 Hz, H-6′),
5.19 (1H, d, J ) 7.8 Hz, H-1′), 5.25, 5.38 (each 1H, d, J ) 13.0
Hz, H2-7), 5.35 (1H, t, J ) 9.5 Hz, H-4′), 5.49 (1H, dd, J ) 9.5,
7.8 Hz, H-2′), 5.55 (1H, t, J ) 9.5 Hz, H-3′), 7.09 (1H, d, J )
7.8 Hz, H-3′′), 7.13 (1H, t, J ) 7.8 Hz, H-5), 7.14 (1H, d, J )
7.8 Hz, H-6), 7.32 (2H, t, J ) 7.8 Hz, H-5, H-5′′), 7.42 (1H, d,
J ) 7.8 Hz, H-3), 7.44 (2H, t, J ) 7.4 Hz, H-3′′′, H-5′′′), 7.56
(1H, dt, J ) 7.9, 1.7 Hz, H-4′′), 7.57 (1H, t, J ) 7.4 Hz, H-4′′′),
7.99 (2H, dd, J ) 7.4, 0.7 Hz, H-2′′′, H-6′′′), 8.07 (1H, dd, J )
7.9, 1.7 Hz, H-6′′); 13C NMR (CDCl3) δ 20.4 (Me) 20.5 (Me),
20.7 (Me), 61.7 (C-7), 61.9 (C-6′), 68.3 (C-4′), 71.0 (C-2′), 72.1
(C-5′), 73.1 (C-3′), 99.5 (C-1′), 116.2 (C-6), 123.3 (C-1′′), 123.7
(C-5′′), 123.9 (C-4), 126.0 (C-3′′), 128.6 (C-3′′′, C-5′′′), 129.6 (C-
5, C-1′′′), 129.7 (C-3), 129.8 (C-2), 129.9 (C-2′′′, C-6′′′), 132.0
(C-6′′), 133.6 (C-4′′), 133.9 (C-4′′′), 150.6 (C-2′′), 154.6 (C-1),
164.2 (C-7′′), 165.8 (C-7′′′), 169.3 (CO), 169.4 (CO), 169.6 (CO),
170.6 (CO); FABMS m/z 619 [M - OAc]+.
Com p ou n d 4 (tr em u la cin ol): colorless amorphous mass;
IR (CHCl3) νmax 3428, 1722 cm-1; UV (MeOH) λmax (log ꢀ) 221
(4.04), 230 (4.01), 273 nm (3.32); ORD (c 0.149, MeOH) [R]
-66.6° (600 nm), -109.7° (500); CD (c 2.8 × 10-5, MeOH) [θ]
1
-54 (283 nm), -304 (267), -42857 (224); H NMR (CDCl3) δ
1.85-1.89 (1H, m, H-5′′), 2.10-2.21 (3H, m, H-5′′, H2-4′′),
3.49-3.52 (1H, m, H-5′), 3.87-4.02 (4H, m, H-3′, H-4′, H2-6′),
4.93, 5.11 (each 1H, d, J ) 12.2 Hz, H2-7), 5.20 (1H, d, J ) 8.0
Hz, H-1′), 5.35 (1H, dd, J ) 9.5, 8.0 Hz, H-2′), 5.44 (1H, d, J )
9.7 Hz, H-2′′), 5.85 (1H, dt, J ) 9.7, 3.5 Hz, H-3′′), 7.00 (1H, t,
J ) 7.9 Hz, H-4), 7.03 (1H, d, J ) 7.9 Hz, H-6), 7.22 (1H, dd,
J ) 7.9, 1.5 Hz, H-3), 7.26 (1H, td, J ) 7.9, 1.5 Hz, H-5), 7.37
(2H, t, J ) 7.6 Hz, H-3′′′, H-5′′′), 7.52 (1H, tt, J ) 7.6, 1.2 Hz,
H-4′′′), 8.02 (2H, dd, J ) 7.6, 1.2 Hz, H-2′′′, H-6′′′); 13C NMR
(CDCl3) δ 24.2 (C-4′′), 26.5 (C-5′′), 60.6 (C-6′), 63.6 (C-7), 69.1
(C-4′′), 74.2 (C-2′), 74.5 (C-3′, C-6′′), 76.3 (C-5′), 77.7 (C-1′′),
115.7 (C-3), 123.2 (C-5), 125.5 (C-1), 126.2 (C-2′′), 128.4 (C-
3′′′, C-4′′′), 130.0 (C-6), 130.2 (C-2′′′, C-6′′′), 131.7 (C-3′′), 133.4
(C-4′′′), 155.2 (C-2), 166.3 (C-7′′′), 172.8 (C-7′′); HRFABMS m/z
553.1668 [M + Na]+, calcd for C27H30O11Na, 553.1686.
Tr em u la cin (2): colorless prisms, mp 122-125 °C (lit.5 mp
122-123 °C); IR (Nujol) νmax 3442, 1727 cm-1; UV (MeOH) λmax
(log ꢀ) 220 (4.29), 272 nm (3.65); ORD (c 0.47, MeOH) [R] -94°
(600 nm), -168° (500); CD (c 0.47, MeOH) [θ] -5303 (268 nm);
1H and 13C NMR, see Table 1; HRFABMS m/z 567.1285 [M +
K]+, calcd for C27H28O11K, 567.1269.
Red u ction of 2 w ith BH3 (r u n 3 in Ta ble 2). A 1 M
solution of BH3 in THF (0.02 mL, 2 × 10-5 mol) was added to
an ice-cooled solution of 2 (0.009 g, 1.7 × 10-5 mol) in THF
(0.5 mL), and then the whole was stirred under ice-cooling for
2 h. After workup, the epimer (4a ) was obtained as a colorless
amorphous mass (0.008 g, 95%): IR (CHCl3) νmax 3426, 1724
cm-1; UV (MeOH) λmax (log ꢀ) 219 (4.06), 230 (3.99), 273 nm
(3.26); ORD (c 6.57 × 10-2, MeOH) [R] -30.4° (600 nm), -57.8°
(500); CD (c 6.9 × 10-5, MeOH) [θ] -129 (283 nm), -3554
(267), -30048 (226); 1H NMR (CDCl3) δ 1.73-1.76 (2H, m, H2-
5′′), 2.11-2.15 (2H, m, H2-4′′), 3.44 (1H, ddd, J ) 9.5, 3.9, 2.6
Hz, H-5′), 3.67 (1H, t, J ) 9.3 Hz, H-4′), 3.76 (1H, t, J ) 9.3
Hz, H-3′), 3.77 (1H, dd, J ) 12.4, 3.9 Hz, H-6′), 3.86 (1H, dd,
J ) 12.4, 2.6 Hz, H-6′), 4.03 (1H, dd, J ) 9.8, 5.9 Hz, H-6),
4.91, 5.07 (each 1H, d, J ) 12.5, H2-7), 5.14 (1H, d, J ) 7.8
Hz, H-1′), 5.23 (1H, dd, J ) 9.3, 7.8 Hz, H-2′), 6.95 (1H, t, J )
7.6 Hz, H-5), 6.98 (1H, d, J ) 7.6 Hz, H-3), 7.16 (1H, d like, J
Hyd r olysis of 2. A mixture of 2 (0.050 g, 9.5 × 10-5 mol)
and 15% aqueous H2SO4 (2.5 mL) was stirred at 100 °C for
1.5 h. After workup, the crude solid was washed with ethyl
acetate to afford salicyl tremuloidin (2a ) as a colorless powder
(0.021 g, 43%): IR (KBr) νmax 3428, 1706, 1673 cm-1; UV
(MeOH) λmax (log ꢀ) 231 (4.37), 274 (3.44), 306 nm (3.56); UV
(MeOH + 1% NaOH) λmax 234, 273, 314 nm; CD (c 1.9 × 10-5
,
MeOH) [θ] -24717 (237 nm), 17698 (220); 1H NMR (CDCl3) δ
3.57 (1H, ddd, J ) 9.5, 4.7, 3.0 Hz, H-5′), 3.72 (1H, t, J ) 9.5
Hz, H-4′), 3.84 (1H, t, J ) 9.5 Hz, H-3′), 3.87 (1H, dd, J )
12.2, 4.7 Hz, H-6′), 3.97 (1H, dd, J ) 12.2, 3.0 Hz, H-6′), 5.23
(1H, d, J ) 8.1 Hz, H-1′), 5.25, 5.29 (each 1H d, J ) 13.1 Hz,