2784
G. Sagrera, G. Seoane
PAPER
13C NMR (100 MHz, acetone-d6): d = 176.6 (C=O), 165.0 (C8a),
162.4 (C4¢, C7), 157.8 (C5), 148.4 (C2), 145.8 (C1¢), 136.8 (C3),
132.8 (C3¢), 130.5 (C2¢), 126.2, 125.8 (C5¢, C6¢), 104.2 (C4a), 99.2
(C6), 94.5 (C8).
MS (EI, 70 eV): m/z (%) = 572 (10.3) [M+ + 2], 571 (28.6) [M+ +
1], 570 (100.0) [M+], 569 (33.4) [M+ – 1], 553 (11.4) [M+ + H –
H2O), 552 (14.8) [M+ – H2O], 543 (64.6) [M+ + H – CO], 525 (19.5)
[M+ – 1 – H2O – CO], 515 (34.1) [M+ + H – 2 CO], 431 (12.4), 417
(19.0), 405 (17.6), 285 (15.6) [M+/2], 165 (73.5), 153 (79.6), 152
(23.4), 137 (16.9), 127 (17.3).
J
5¢6¢ = 8.8 Hz, 1 H, H5¢), 6.67 (s, 1 H, H3), 6.56 (d, J68 = 2.1 Hz, 1
H, H6), 6.37 (d, J86 = 2.1 Hz, 1 H, H8), 3.95 (s, 3 H, OMe), 3.88 (s,
3 H, OMe), 3.86 (s, 3 H, OMe).
13C NMR (100 MHz, CDCl3): d = 176.5 (C=O), 164.0 (C2), 162.1
(C4¢), 161.0 (C7, C8a), 157.9 (C5), 144.8 (C1¢), 129.5 (C2¢), 129.1
(C6¢), 126.2 (C3¢, C5¢), 112.9 (C4a), 112.2 (C8), 104.0 (C3), 94.3
(C6), 56.0, 55.8, 55.7 (3 OMe).
MS (EI, 70 eV): m/z (%) = 623 (29.6) [M+ + 1], 622 (59.9) [M+],
621 (7.4) [M+ – 1], 608 (29.6), 607 (100.0) [M+ – CH3], 310 (5.6,
[M+/2 – 1], 302 (16.7), 296 (23.5), 126 (8.0) [C6H3(OH)3 ], 97 (7.4)
+
Anal. Calcd for C30H18O12: C, 63.16; H, 3.18. Found: C, 63.02; H,
3.27.
[C6H3(OH)3 – 1 – CO], 43 (8.0) [CH3CO+].
Anal. Calcd for C36H30O10: C, 69.45; H, 4.86. Found: C, 69.68; H,
4.55.
2¢,2¢¢¢,4,4¢,4¢¢,4¢¢¢,6¢,6¢¢¢-Octahydroxy-3,3¢¢-bidihydrochalcone
(16)
Following general procedure 3 using 42 (108 mg, 0.1 mmol) stirring
at r.t. for 1 h gave 16 as a whitish solid; yield: 44 mg (81%); mp
155.5–158 °C.
1H NMR (400 MHz, CDCl3): d = 13.95 (s, 1 H, 2¢-OH), 6.75–6.71
(m, 2 H, H2, H6), 6.46–6.36 (m, 1 H, H5), 6.17 (d, J5¢3¢ = 2.0 Hz, 1
H, H5¢), 6.09 (d, J3¢5¢ = 2.0 Hz, 1 H, H3¢), 3.23 (t, Jab = 7.8 Hz, 2 H,
CH2a), 2.81 (t, Jba = 7.7 Hz, 2 H, CH2b).
13C NMR (100 MHz, CDCl3): d = 204.5 (C=O), 167.6 (C6¢), 164.9
(C4¢), 161.8 (C2¢), 148.9 (C4), 135.4, 135.0 (C1¢, C2¢), 127.3 (C3,
C6), 115.6 (C5), 106.1 (C1¢), 94.9 (C5¢), 92.4 (C3¢), 45.9 (CH2a),
29.8 (CH2b).
3,3¢¢-Dihydroxy-4¢,4¢¢¢,5,5¢¢,7,7¢¢-hexamethoxy-3¢,3¢¢¢-biflavone
(39)
Following general procedure 6 using 38 (125 mg, 0.2 mmol), KOH
(1 mmol), and IBD (0.44 mmol) with stirring at r.t. for 48 h to give
39; yield: 81 mg (62%).
1H NMR (400 MHz, CDCl3): d = 8.11 (s, 1 H, 3-OH), 7.69 (d,
J2¢6¢ = 2.2 Hz, 1 H, H2¢), 7.51 (d, J6¢5¢ = 8.4 Hz, J6¢2¢ = 2.2 Hz, 1 H,
H6¢), 6.90 (d, J5¢6¢ = 8.4 Hz, 1 H, H5¢), 6.42 (d, J86 = 2.1 Hz, 1 H,
H8), 6.19 (d, J68 = 2.1 Hz, 1 H, H6), 3.89 (s, 3 H, OMe), 3.85 (s, 3
H, OMe), 3.84 (s, 3 H, OMe).
13C NMR (100 MHz, CDCl3): d = 177.1 (C=O), 165.3 (C8a), 162.8
(C4¢, C7), 158.2 (C5), 148.2 (C2), 145.2 (C1¢), 136.9 (C3), 132.9
(C3¢), 130.7 (C2¢), 126.7, 126.2 (C5¢, C6¢), 104.3 (C4a), 99.8 (C6),
95.1 (C8), 56.1, 55.9, 55.6 (3 OMe).
MS (EI, 70 eV): m/z (%) = 548 (3.2) [M+ + 2], 547 (11.4) [M+ + 1],
546 (22.0) [M+], 545 (3.7) [M+ – 1], 528 (18.3) [M+ – H2O], 527
(20.0) [M+ – H2O – H], 393 (76.4), 379 (43.8), 273 (8.2) [M+/2], 210
(10.1), 153 (100.0) [C6H2(OH)3CO+], 152 (38.4) [C6H2(OH)3CO –
1]+.
MS (EI, 70 eV): m/z (%) = 656 (9.2) [M+ + 2], 655 (15.4) [M+ + 1],
654 (100.0) [M+], 570 (43.4).
Anal. Calcd for C36H30O12: C, 66.05; H, 4.62. Found: C, 66.32; H,
4.80.
Anal. Calcd for C30H26O10: C, 65.93; H, 4.79. Found: C, 66.25; H,
5.03.
2¢,2¢¢¢4,4¢,4¢¢,4¢¢¢-Hexakis(benzyloxy)-6¢,6¢¢¢-dihydroxy-3,3¢¢-
bichalcone (42)
Following general procedure 1 using 40 (2 mmol), 41 (1 mmol), and
NaH (5 mmol) stirring at r.t. for 24 h gave 42 as a yellow solid;
yield: 875 mg (81%); mp 133.5–136.0 °C.
1H NMR (400 MHz, CDCl3): d = 13.99 (s, 1 H, 2¢-OH), 7.80 (d,
Jba = 15.6 Hz, 1 H, Hb), 7.75 (d, Jab = 15.6 Hz, 1 H, Ha), 7.44–6.95
(m, 17 H, 15 HPh, H2, H6), 6.78 (d, J56 = 8.6 Hz, 1 H, H5), 6.23 (d,
2¢,2¢¢¢-Dihydroxy-4,4¢,4¢¢,4¢¢¢,6¢,6¢¢¢-hexamethoxy-3,3¢¢-bichal-
cone (37)46
Following general procedure 1 using 34 (2 mmol), 36 (1 mmol), and
NaH (5 mmol) stirring at r.t. for 24 h gave 37 as a yellow solid;
yield: 532 mg (85%); mp 178.3–182.2 °C.
1H NMR (400 MHz, CDCl3): d = 14.34 (s, 1 H, 2¢-OH), 7.83 (d,
Jba = 15.4 Hz, 1 H, Hb), 7.79 (d, Jab = 15.4 Hz, 1 H, Ha), 7.62 (dd,
J65 = 8.6 Hz, J62 = 2.3 Hz, 1 H, H6), 7.53 (d, J26 = 2.2 Hz, 1 H, H2),
7.01 (d, J56 = 8.6 Hz, 1 H, H5), 6.10 (d, J3¢5¢ = 2.4 Hz, 1 H, H3¢), 5.94
(d, J5¢3¢ = 2.4 Hz, 1 H, H5¢), 3.87 (s, 3 H, OMe), 3.83 (s, 3 H, OMe),
3.82 (s, 3 H, OMe).
13C NMR (100 MHz, CDCl3): d = 192.6 (C=O), 168.3, 166.1, 162.5
(C2¢, C4¢, C6¢), 158.9 (C4), 152.0 (C1), 142.4 (Cb), 131.5 (C2),
129.9 (C6), 128.2, 127.7 (C5, C3), 125.5 (Ca), 106.5 (C1¢), 93.9
(C5¢), 91.3 (C3¢), 55.92 (OMe), 55.88 (OMe), 55.6 (OMe).
MS (EI, 70 eV): m/z (%) = 627 (13.0) [M+ + 1], 626 (34.9) [M+],
625 (15.9) [M+ – 1], 611 (25.0) [M+ – CH3], 446 (23.4), 445 (53.3),
433 (17.6), 266 (24.0) [M+/2 –1 – H2O – CO], 253 (42.7) [M+/2 + 1
– H2O – CO – CH3], 207 (54.7), 182 (10.6), 181 (100.0), 180 (10.3),
166 (10.4), 152 (11.1), 137 (17.7).
HRMS (EI+, 70 eV): m/z [M]+ calcd for C36H34O10: 626.2152;
found: 626.2130.
J
5¢3¢ = 2.3 Hz, 1 H, H5¢), 6.15 (d, J3¢5¢ = 2.3 Hz, 1 H, H3¢), 5.10 (s, 2
H, CH2), 5.01 (s, 2 H, CH2), 5.00 (s, 2 H, CH2).
13C NMR (100 MHz, CDCl3): d = 192.6 (C=O), 168.6 (C4¢), 165.1
(C2¢), 161.7 (C6¢), 157.9 (C4), 149.8 (C1), 142.9 (Cb), 136.9, 135.9,
135.4 (3 C1Ph), 132.0 (C2), 129.5, 128.71, 128.68, 128.4, 128.3,
128.14, 128.11, 128.0, 127.6, (3 C2Ph–C6Ph, C3), 126.5, 125.4 (C5,
C6, Ca), 106.6 (C1¢), 95.1 (C5¢), 92.6 (C3¢), 71.3 (CH2), 70.3 (CH2),
70.2 (CH2).
MS (EI, 70 eV): m/z (%) = 627 (7.8) [M+ – 5 Bn], 537 (12.3) [M+ +
1 – 6 Bn], 536 (2.8) M+ – 6 Bn], 518 (5.0) [M+ – 6 Bn – H2O], 269
(5.1) [(M+ – 6 Bn)/2 + 1], 152 (21.2), 125 (5.6 [C6H3(OH)2O+], 91
(100.0) [Bn+].
Anal. Calcd for C72H58O10: C, 79.85; H, 5.36. Found: C, 80.14; H,
5.15.
4¢,4¢¢¢,5,5¢¢,7,7¢¢-Hexakis(benzyloxy)-3¢,3¢¢¢-biflavanone (51) and
4¢,4¢¢¢,7,7¢¢-Tetrakis(benzyloxy)-5,5¢¢-dihydroxy-3¢,3¢¢¢-bifla-
vanone (52)
Following general procedure 2 using bichalcone 42 (541 mg, 0.5
mmol) at reflux for 96 h gave 51 (297 mg, 55%) and 52 (55 mg,
10%).
4¢,4¢¢¢,5,5¢¢,7,7¢¢-Hexamethoxy-3¢,3¢¢¢-biflavone (38)43
Following general procedure 4 using bichalcone 37 (313 mg, 0.5
mmol) and I2 (2.5 mg, 0.01 mmol) gave 38 as a white solid; yield:
270 mg (87%); mp 348–349.6 °C (Lit.43 354 °C).
1H NMR (400 MHz, acetone-d6): d = 7.90 (dd, J6¢5¢ = 8.7 Hz,
J6¢2¢ = 2.3 Hz, 1 H, H6¢), 7.80 (d, J2¢6¢ = 2.2 Hz, 1 H, H2¢), 7.10 (d,
Synthesis 2010, No. 16, 2776–2786 © Thieme Stuttgart · New York