Helvetica Chimica Acta – Vol. 92 (2009)
2007
5 (49.0 mg). Fr. C (with hexane/AcOEt 5 :1) was separated by CC (Chromatorex DMS, MeOH/H2O
2 :3 ! 1:0). The resulting fractions were further purified by CC (Sephadex LH-20, MeOH) and VLC
(SiO2, hexane/benzene 5 :1 ! 1:1): 1 (230.6 mg), 2 (4.3 mg), 5 (18.7 mg), 8 (153.2 mg), and 9
(100.6 mg). Fr. E (with hexane/AcOEt 1:1) was separated by CC (Chromatorex DMS, MeOH/H2O
2 :3 ! 1:0). The fractions containing flavonoids were purified by CC (Sephadex LH-20, MeOH) and
VLC (SiO2, benzene/EtOH 40 :1 ! 1:1) and subsequently by prep. TLC (benzene/EtOH 20 :1): 4
(40.0 mg), 6 (32.2 mg), and 7 (48.0 mg) in pure forms, and 10/11 (21.7 mg) and 12/13 (23.7 mg) as
mixtures of the corresponding isomers. TLC: detection by 10% H2SO4 soln. made 1 – 4 orange, and, on
the contrary, 5 and 6 yellow.
Daemonorol A (¼ 8,8’-Methylenebis[3,4-dihydro]-5-methoxy-2-phenyl-2H-1-benzopyran-7-ol; 1):
Colorless solid. [a]2D5 ¼ ꢀ118 (c ¼ 0.1, CHCl3). UV (CHCl3): 277 (3.52). 1H- and 13C-NMR: Table 1.
EI-MS: 524 (56, Mþ), 505 (16), 420 (28), 401 (8), 316 (8), 269 (100), 256 (43), 165 (44), 104 (50). HR-EI-
MS: 524.2207 (Mþ, C33H32O6þ; calc. 524.2199).
Daemonorol B (¼6,8’-Methylenebis[3,4-dihydro]-5-methoxy-2-phenyl-2H-1-benzopyran-7-ol ¼ 6-
[(3,4-Dihydro-7-hydroxy-5-methoxy-2-phenyl-2H-1-benzopyran-8-yl)methyl]-3,4-dihydro-5-methoxy-2-
phenyl-2H-1-benzopyran-7-ol; 2): Colorless solid. [a]2D5 ¼ ꢀ116 (c ¼ 0.1, CHCl3). UV (CHCl3): 281
(3.63). 1H- and 13C-NMR: Table 2. EI-MS: 524 (37, Mþ), 420 (8), 401 (8), 269 (100), 256 (54), 165 (34),
104 (42). HR-EI-MS: 524.2205 (Mþ, C33H32O6þ ; calc. 524.2199).
Daemonorol C (¼ 8-[(3,4-Dihydro-7-hydroxy-5-methoxy-2-phenyl-2H-1-benzopyran-8-yl)methyl]-
3,4-dihydro-5-methoxy-2-phenyl-2H-1-benzopyran-7-ol; 3): Colorless solid. [a]2D5 ¼ ꢀ85 (c ¼ 0.1, CHCl3).
UV (CHCl3): 273 (3.82). 1H- and 13C-NMR: Table 2. EI-MS: 538 (80, Mþ), 434 (8), 282 (88), 269 (100),
256 (40), 179 (28), 165 (60), 152 (24), 104 (82). HR-EI-MS: 538.2362 (Mþ, C34H34O6þ ; calc. 538.2355).
Daemonorol D (¼ 5-Methoxy-6-methyl-2-phenyl-4H-1-benzopyran-7-ol; 4): Red solid. UV
(MeOH): 316 (3.07), 283 (3.65), 228 (4.26). 1H- and 13C-NMR: Table 3. EI-MS: 268 (100, Mþ), 252
(16), 237 (12), 191 (20). HR-EI-MS: 268.1107 (Mþ, C17H16O3þ ; calc. 268.1100).
Daemonorol E (¼(2S)-3,4-Dihydro-2-(4-hydroxyphenyl)-5-methoxy-2H-benzopyrane-7-ol; 5): Col-
orless solid. [a]2D5 ¼ ꢀ85 (c ¼ 0.1, MeOH). UV (MeOH): 281 (3.83), 230 (4.69). CD (c ¼ 0.01, MeOH):
281 (ꢀ0.93). 1H- and 13C-NMR: Table 3. EI-MS: 272 (100, Mþ), 153 (93), 120 (60). HR-EI-MS: 272.1044
(Mþ, C17H18Oþ4 ; calc. 272.1049).
Daemonorol F (¼ 3-(2,4-Dihydroxy-6-methoxy-3-methylphenyl)-1-phenylpropan-1-one; 6): Color-
1
less solid. UV (MeOH): 279 (3.16), 238 (3.98). H- and 13C-NMR: Table 4. EI-MS: 286 (60, Mþ), 267
(8), 256 (7), 167 (100), 154 (71), 137 (11), 105 (33), 77 (22). HR-EI-MS: 286.1211 (Mþ, C17H18O4þ ; calc.
286.1205).
Catalytic Hydrogenation of 4. A mixture of 4 (3.5 mg) and 5% Pd/C (7 mg) in EtOH (6 ml) was
stirred under H2 at r.t. overnight. The mixture was filtered, the filtrate concentrated, and the residue
purified by prep. TLC (benzene/AcOEt 10 :1): 1.0 mg of reduced product. The product was identified as
(2S)-5-methoxy-6-methylflavan-7-ol ( ¼ (2S)-3,4-dihydro-5-methoxy-6-methyl-2-phenyl-2H-1-benzopyr-
an-7-ol) by comparison with the 1H-NMR data and Rf value on TLC (benzene/AcOEt 10 :1) of 9.
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