W.-J. Jiang et al. / Bioorg. Med. Chem. xxx (2015) xxx–xxx
5
12
(2R,3R)-isomer: [
a
]
+4.7° (c = 1.0, MeOH), CD (MeOH):
D
e
(OCH3-40), 56.2 (OCH3-20), 72.1 (C-3), 78.8 (C-2), 96.0 (C-6), 97.0
(C-8), 99.3 (C-50), 101.6 (C-10), 105.9 (C-30), 118.1 (C-10), 130.7
(C-60), 160.4 (C-40), 162.6 (C-20), 164.6 (C-5), 165.1 (C-9), 167.9
(C-7), 198.7 (C-4). HR-EI-MS: m/z 332.0897 [M]+ (Calcd 332.0896
for C17H16O7).
D
(nm) ꢁ6.52 (288.7), +2.08 (327.1) (c = 6.62 ꢀ 10ꢁ5). (2S,3S)-isomer:
12
[
a
]
ꢁ5.5° (c = 1.0, MeOH), CD (MeOH):
De (nm) +6.54 (289.6),
D
ꢁ2.01 (324.2) (c = 6.62 ꢀ 10ꢁ5).
2.10.13. 3,5,7-Trihydroxy-40-methoxy flavanonol (5l)
Separation by chiral chromatography: EtOH–n-hexane (20:80 v/v)
Retention time (2R,3R)-isomer: 11.50 min, (2S,3S)-isomer:
1H NMR (600 MHz, acetone-d6) d: 3.83 (3H, s, OCH3-40), d 4.67
(1H, d, J = 11.2 Hz, H-3), 5.13 (1H, d, J = 11.2 Hz, H-2), 5.96 (1H, d,
J = 1.8 Hz, H-6), 6.00 (1H, d, J = 1.8 Hz, H-8), 7.00 (2H, d,
J = 9.0 Hz, H-30, H-50), 7.52 (2H, d, J = 9.0 Hz, H-20, H-60). 13C NMR
(150 MHz, acetone-d6) d: 54.8 (OCH3-40), 72.3 (C-3), 83.3 (C-2),
95.2 (C-6), 96.3 (C-8), 100.7 (C-10), 113.7 (C-30, C-50), 129.4 (C-20,
C-60), 129.5 (C-10), 160.3 (C-40), 163.3 (C-5), 164.2 (C-9), 167.0
(C-7), 197.4 (C-4). HR-EI-MS: m/z 302.0788 [M]+ (Calcd 302.0790
for C16H14O6).
10.50 min.
12
(2R,3R)-isomer: [
a]
+77.7° (c = 1.0, MeOH), CD (MeOH): De
D
(nm) ꢁ4.84 (292.3), +1.70 (326.7) (c = 6.06 ꢀ 10ꢁ5). (2S,3S)-isomer:
12
[a
]
D
ꢁ75.0° (c = 1.0, MeOH), CD (MeOH):
De (nm) +4.28 (291.5),
ꢁ1.70 (324.7) (c = 6.06 ꢀ 10ꢁ5).
2.10.17. 3,5,7-Trihydroxy-20,50-dimethoxy flavanonol (5p)
Colorless powder, mp 223–225 °C; IR (KBr) mmax
1638 cmꢁ1; UV kmax (MeOH) nm (log ): 293 (4.13), 320 (sh); 1H
:
3428,
Separation by chiral chromatography: EtOH–n-hexane (25:75 v/v)
Retention time (2R,3R)-isomer: 10.22 min, (2S,3S)-isomer:
e
NMR (600 MHz, acetone-d6) d: 3.78 (3H, s, OCH3-20), 3.80 (3H, s,
OCH3-50), 4.86 (1H, d, J = 12.0 Hz, H-3), 5.60 (1H, d, J = 12.0 Hz, H-
2), 5.95 (1H, d, J = 1.8 Hz, H-6), 6.00 (1H, d, J = 1.8 Hz, H-8), 6.95
(1H, dd, J = 9.0, 2.4 Hz, H-40), 7.02 (1H, d, J = 9.0 Hz, H-30), 7.19
(1H, d, J = 2.4 Hz, H-60). 13C NMR (150 MHz, acetone-d6) d: 56.0
(OCH3-20), 57.0 (OCH3-50), 72.4 (C-3), 78.6 (C-2), 96.1 (C-6), 97.2
(C-8), 101.7 (C-10), 113.8 (C-30), 115.5 (C-60), 115.6 (C-40), 127.0
(C-10), 153.3 (C-20), 154.8 (C-50), 164.4 (C-5), 165.2 (C-9), 167.9
(C-7), 198.4 (C-4). HR-EI-MS: m/z 332.0901 [M]+ (Calcd 332.0896
for C17H16O7).
8.58 min.
12
(2R,3R)-isomer: [
a
]
+15.6° (c = 1.0, MeOH), CD (MeOH): De
D
(nm) ꢁ7.68 (288.4), +2.26 (327.4) (c = 6.62 ꢀ 10ꢁ5). (2S,3S)-isomer:
12
[
a]
ꢁ21.0° (c = 1.0, MeOH), CD (MeOH):
De (nm) +8.02 (288.8),
D
ꢁ2.23 (326.7) (c = 6.62 ꢀ 10ꢁ5).
2.10.14. 3,5,7-Trihydroxy-20,60-dimethoxy flavanonol (5m)
Colorless powder, mp 268–270 °C; IR (KBr) mmax
1637 cmꢁ1; UV kmax (MeOH) nm (log ): 288 (4.22), 320 (sh); 1H
:
3478,
e
NMR (600 MHz, acetone-d6) d: 3.83 (6H, s, OCH3-20, OCH3-60),
5.40 (1H, d, J = 12.6 Hz, H-3), 5.81 (1H, d, J = 12.6 Hz, H-2), 5.90
(1H, d, J = 2.4 Hz, H-6), 5.97 (1H, d, J = 2.4 Hz, H-8), 6.72 (1H, d,
J = 8.4 Hz, H-30, H-50), 7.36 (1H, t, J = 8.4 Hz, H-40). 13C NMR
(150 MHz, acetone-d6) d: 56.4 (OCH3-20, OCH3-60), 70.4 (C-3), 76.3
(C-2), 95.9 (C-6), 96.8 (C-8), 101.6 (C-10), 105.5 (C-30, C-50), 113.2
(C-10), 131.9 (C-40), 161.0 (C-20, C-60), 165.2 (C-5), 165.3 (C-9),
167.5 (C-7), 199.6 (C-4). HR-EI-MS: m/z 332.0895 [M]+ (Calcd
332.0896 for C17H16O7). The Enantiomers of 5m could not be sep-
arated using chiral chromatography.
Separation by chiral chromatography: EtOH–n-hexane (50:50 v/
v) Retention time (2R,3R)-isomer: 5.00 min, (2S,3S)-isomer:
4.30 min.
12
(2R,3R)-isomer: [
a]
+46.7° (c = 1.0, MeOH), CD (MeOH): De
D
(nm) ꢁ4.64 (286.6), +1.86 (325.2) (c = 6.06 ꢀ 10ꢁ5). (2S,3S)-isomer:
12
[a
]
D
ꢁ47.4° (c = 1.0, MeOH), CD (MeOH):
De (nm) +4.43 (288.8),
ꢁ1.84 (325.9) (c = 6.06 ꢀ 10ꢁ5).
2.10.18. 3,5,7-Trihydroxy-30,40-dimethoxy flavanonol (5q)
1H NMR (600 MHz, acetone-d6) d: 3.84 (3H, s, OCH3-40), 3.85
(3H, s, OCH3-30), 4.71 (1H, d, J = 12.0 Hz, H-3), 5.11 (1H, d,
J = 12.0 Hz, H-2), 5.96 (1H, d, J = 1.8 Hz, H-6), 6.00 (1H, d,
J = 1.8 Hz, H-8), 6.99 (1H, d, J = 1.8 Hz, H-50), 7.11 (1H, dd, J = 8.4,
1.8 Hz, H-60), 7.22 (1H, d, J = 1.8 Hz, H-20). 13C NMR (150 MHz, ace-
tone-d6) d: 56.2 (OCH3-40), 56.3 (OCH3-30), 73.2 (C-3), 84.6 (C-2),
96.1 (C-6), 97.2 (C-8), 101.6 (C-10), 112.4 (C-50), 112.6 (C-20),
121.8 (C-60), 130.7 (C-10), 150.3 (C-30), 151.0 (C-40), 164.2 (C-5),
165.1 (C-9), 167.9 (C-7), 198.3 (C-4). HR-EI-MS: m/z 332.0896
[M]+ (Calcd 332.0896 for C17H16O7). The enantiomers of 5q could
not be separated using chiral chromatography.
2.10.15. 3,5,7-Trihydroxy-20,30-dimethoxy flavanonol (5n)
Colorless powder, mp 233–235 °C; IR (KBr) mmax
: 3432,
1632 cmꢁ1; UV kmax (MeOH) nm (log ): 290 (4.33), 320 (sh); 1H
e
NMR (600 MHz, acetone-d6) d: 3.83 (3H, s, OCH3-30), 3.89 (3H, s,
OCH3-20), 4.81 (1H, d, J = 12.0 Hz, H-3), 5.58 (1H, d, J = 12.0 Hz, H-
2), 5.95 (1H, d, J = 1.8 Hz, H-6), 6.01 (1H, d, J = 1.8 Hz, H-8), 7.09
(1H, dd, J = 7.8, 1.8 Hz, H-60), 7.16 (1H, dd, J = 7.8, 7.8 Hz, H-50),
7.22 (1H, dd, J = 7.8, 1.8 Hz, H-40). 13C NMR (150 MHz, acetone-
d6) d: 56.3 (OCH3-20), 61.4 (OCH3-30), 72.4 (C-3), 78.9 (C-2), 96.1
(C-6), 97.2 (C-8), 101.6 (C-10), 114.1 (C-60), 120.9 (C-50), 124.9
(C-40), 131.6 (C-10), 149.3 (C-20), 154.0 (C-30), 164.3 (C-5), 165.2
(C-9), 167.9 (C-7), 198.4 (C-4). HR-EI-MS: m/z 332.0897 [M]+ (Calcd
332.0896 for C17H16O7).
2.10.19. 3,5,7-Trihydroxy 30,50-dimethoxy flavanonol (5r)
Colorless powder, mp 191–193 °C; IR (KBr) mmax
: 3474,
1644 cmꢁ1; UV kmax (MeOH) nm (log ): 289 (4.14), 318 (sh); 1H
e
Separation by chiral chromatography: EtOH–n-hexane (25:75 v/
v) Retention time (2R,3R)-isomer: 7.13 min, (2S,3S)-isomer:
NMR (600 MHz, acetone-d6) d: 3.81 (6H, s, OCH3-30, OCH3-50),
4.67 (1H, d, J = 12.0 Hz, H-3), 5.11 (1H, d, J = 12.0 Hz, H-2), 5.98
(1H, d, J = 2.4 Hz, H-6), 6.01 (1H, d, J = 2.4 Hz, H-8), 6.52 (1H, dd,
J = 2.4, 2.4 Hz, H-40), 6.77 (2H, d, J = 2.4 Hz, H-20, H-60). 13C NMR
(150 MHz, acetone-d6) d: 55.8 (OCH3-30, OCH3-50), 73.2 (C-3),
84.5 (C-2), 96.2 (C-6), 97.3 (C-8), 101.2 (C-40), 101.6 (C-10), 107.0
(C-20, C-60), 140.5 (C-10), 161.8 (C-30, C-50), 164.0 (C-5), 165.1 (C-
9), 167.9 (C-7), 198.0 (C-4). HR-EI-MS: m/z 332.0901 [M]+ (Calcd
332.0896 for C17H16O7).
6.05 min.
12
(2R,3R)-isomer: [
a
]
+61.6° (c = 1.0, MeOH), CD (MeOH): De
D
(nm) ꢁ2.76 (290.7), +1.35 (323.2) (c = 6.06 ꢀ 10ꢁ5). (2S,3S)-isomer:
12
[
a]
D
ꢁ73° (c = 1.0, MeOH), CD (MeOH):
De (nm) +2.75 (290.9),
ꢁ1.41 (324.6) (c = 6.06 ꢀ 10ꢁ5).
2.10.16. 3,5,7-Trihydroxy-20,40-dimethoxy flavanonol (5o)
Colorless powder, mp 203–205 °C; IR (KBr) mmax
1639 cmꢁ1; UV kmax (MeOH) nm (log ): 289 (4.19), 318 (sh); 1H
:
3478,
Separation by chiral chromatography: EtOH–n-hexane (80:20 v/
v) Retention time (2R,3R)-isomer: 6.83 min, (2S,3S)-isomer:
e
NMR (600 MHz, acetone-d6) d: 3.83 (3H, s, OCH3-20), 3.83 (3H, s,
OCH3-40), 4.85 (1H, d, J = 12.0 Hz, H-3), 5.51 (1H, d, J = 12.0 Hz, H-
2), 5.91 (1H, d, J = 2.4 Hz, H-6), 5.98 (1H, d, J = 2.4 Hz, H-8), 6.59
(1H, d, J = 2.4 Hz, H-30), 6.61 (1H, dd, J = 8.4, 2.4 Hz, H-50), 7.47
(1H, d, J = 8.4 Hz, H-60). 13C NMR (150 MHz, acetone-d6) d: 55.8
4.17 min.
12
(2R,3R)-isomer: [
a
]
+0.8° (c = 1.0, MeOH), CD (MeOH): De
D
(nm) ꢁ5.84 (292.0), +1.98 (328.3) (c = 6.06 ꢀ 10ꢁ5). (2S,3S)-isomer:
12
[a
]
D
ꢁ0.8° (c = 1.0, MeOH), CD (MeOH):
De (nm) +5.46 (290.1),
ꢁ1.84 (324.7) (c = 6.06 ꢀ 10ꢁ5).