A round bottom flask was charged with the opportune
isoflavone (200 mg) and 2 mL of pyridine. A solution of 0.6 mL
of methanesulfonyl chloride in pyridine (3 mL) was added and
the resulting mixture was stirred at room temperature. The
reaction was monitored by TLC (hexane/ethyl acetate 1:1) and,
after completion, it was quenched by pouring the mixture in cold
water. The resulting solid was collected by filtration and
recrystallized from ethanol.
110.2, 109.8, 108.9, 108.2, 107.2, 105.4, 102.1, 77.1, 29.1, 28.5,
25.2, 21.6, 17.9. HMRS (ESI) found 577.1642, calc. 577.1124.
Anal. found C 56.2, H 4.9, S 11.1. Calc. for C27H28O10S2: C 56.2,
H 4.9, S 11.1%.
4.4.5 Characterization of 4-(2,2,10,10-tetramethyl-8-oxo-
8,10,11,12-tetrahydro-2H-dipyrano[2,3-f:2',3'-h]chromen-7-yl)-
1,2-phenylene dimethanesulfonate (13)
4.4.1. Characterization of 4-(5-hydroxy-8,8-dimethyl-6-(3-
methylbut-2-en-1-yl)-4-oxo-4,8-dihydropyrano[2,3-f]chromen-3-
yl)-1,2-phenylene dimethanesulfonate (5)
Yield: 71%. δH (400 MHz, CDCl3): 7.84 (1H, s, C=CH), 7.73
(1H, d, J 1.8, Ar-H), 7.59 (1H, d, J 8.4 Hz, Ar-H), 7.53 (1H, d, J
8.4 Hz, Ar-H), 6.75 (1H, d, J 10.0 Hz, C=CH), 5.60 (1H, d, J
10.0 Hz, C=CH), 3.28 (3H, s, CH3), 3.27 (3H, s, CH3),2.69 (2H,
m, CH2), 1.86 (2H, m, CH2), 1.52 (6H, s, CH3), 1.45 (6H, s, CH3).
δC (100 MHz, CDCl3): 182.1, 159.2, 156.1, 152.0, 150.2, 144.5,
140.2, 137.5, 128.1, 119.0, 113.1, 110.0, 108.1, 108.0, 103.1,
102.2, 89.1, 83.5, 38.1, 37.6, 33.3, 29.4, 27.1, 26.1. HMRS (ESI)
found 729.1745, calc. 729.1758. Anal. found C 63.1, H 5.1, S 8.8.
Calc. for C39H39O10S2: C 63.1, H 5.0, S 8.8%.
Yield: 71%. δH (400 MHz, CDCl3): 12.88 (1H, s, OH), 7.98
(1H, s, C=CH), 7.74 (1H, m, Ar-H), 7.57 (2H, m, Ar-H), 6.70
(1H, d, J 9.9 Hz, C=CH), 5.62 (1H, d, J 9.9 Hz, C=CH), 5.23 (1H,
m, C=CH), 3.36 (2H, d, J 7.1 Hz, CH2), 3.31 (3H, s, CH3), 3.30
(3H, s, CH3), 1.83 (3H, s, CH3), 1.70 (3H, s, CH3), 1.51 (6H, s,
CH3). δC (100 MHz, CDCl3): 182.1, 161, 159.2, 154.6, 150.9,
133.5, 132.3, 132.2, 129.1,124.3, 124, 123.5, 116.5, 115, 107.2,
102.6, 79.7, 78.4, 39.2, 29.9, 27.5, 23, 19.7. HMRS (ESI) found
577.1642, calc. 577.1124 Anal. found C 56.1, H 4.9, S 11.1. Calc.
for C27H28O10S2: C 56.2, H 4.9, S 11.1%.
4.5. General procedure for the preparation of 4-
methylbenzenesulfonate derivatives
A round bottom flask was charged with the opportune
isoflavone (100 mg) and 1 mL of pyridine. A solution of 400 mg
of 4-methylbenzenesulfonyl chloride in pyridine (2 mL) was
added and the resulting mixture was stirred at room temperature.
The reaction was monitored by TLC (hexane/ethyl acetate 1:1)
and, after completion, it was quenched by pouring the mixture in
cold water. The resulting solid was collected by filtration and
recrystallized from ethanol.
4.4.2. Characterization of 4-(5-hydroxy-8,8-dimethyl-6-(3-
methylbut-2-en-1-yl)-4-oxo-4,8-dihydropyrano[2,3-f]chromen-3-
yl)phenyl methanesulfonate (6)
Yield: 69%. δH (400 MHz, CDCl3): 13.02 (1H, s, OH), 7.93
(1H, s, C=CH), 7.60 (2H, d, J 8.8 Hz, Ar-H), 7.38 (2H, d, J 8.8
Hz, Ar-H), 6.71 (1H, d, J 9.9 Hz, C=CH), 5.61 (1H, d, J 9.9 Hz,
C=CH), 5.25 (1H, m, C=CH), 3.36 (2H, d, J 7.1 Hz, CH2), 3.20
(3H, s, CH3), 1.83 (3H, s, CH3), 1.71 (3H, s, CH3), 1.50 (6H, s,
CH3). δC (100 MHz, CDCl3): 180.3, 159.2, 157.4, 152.8, 150.4,
149.1, 131.7, 130.6, 130.4, 127.4, 122.5, 122.1, 121.7, 114.7,
113.1, 105.4, 100.8, 78, 37.4, 28.1, 25.8, 21.3, 17.9. HMRS
(ESI) found 483.1695, calc. 483.1399. Anal. found C 64.7, H 5.4,
S 6.5. Calc. for C26H26O7S C 64.7, H 5.4, S 6.6%.
4.5.1. Characterization of 4-(5-hydroxy-8,8-dimethyl-6-(3-
methylbut-2-en-1-yl)-4-oxo-4,8-dihydropyrano[2,3-f]chromen-3-
yl)phenyl 4-methylbenzenesulfonate (7)
Yield 68%. δH (400 MHz, CDCl3): 12.98 (1H, s, OH), 7.89
(1H, s, C=CH), 7.77 (2H, m, Ar-H), 7.49 (2H, m, Ar-H), 7.35
(2H, d, J 7.9 Hz, Ar-H), 7.08 (2H, m, Ar-H), 6.69 (1H, d, J 9.9
Hz, C=CH), 5.60 (1H, d, J 9.9 Hz, C=CH), 5.23 (1H, m, C=CH),
3.36 (2H, m, CH2), 2.49 (3H, s, CH3), 1.83 (3H, s, CH3), 1.70
(3H, s, CH3), 1.50 (6H, s, CH3). δC (100 MHz, CDCl3): 180.2,
159.3, 152.8, 145.4,130.1, 130, 129.8, 128.5, 127.3, 122.4, 121.7,
114.8, 28.1, 25.7, 21.7, 17.9. HMRS (ESI) found 559.2178, calc.
559.1712. Anal. found C 68.9, H 5.4, S 5.6. Calc. for C32H30O7S
C 68.8, H 5.4, S 5.7%.
4.4.3 Characterization of 4-(5-hydroxy-8,8-dimethyl-10-(3-
methylbut-2-en-1-yl)-4-oxo-4,8-dihydropyrano[3,2-g]chromen-3-
yl)phenyl methanesulfonate (9)
Yield: 55%. δH (400 MHz, CDCl3): 13.00 (1H, s, OH), 7.93
(1H, s, C=CH), 7.59 (2H, d, J 8.8 Hz, Ar-H), 7.40 (2H, d, J 8.8
Hz, Ar-H), 6.70 (1H, d, J 9.9 Hz, C=CH), 5.61 (1H, d, J 9.9 Hz,
C=CH), 5.25 (1H, m, C=CH), 3.38 (2H, m, CH2), 3.20 (3H, s,
CH3), 1.83 (3H, s, CH3), 1.70 (3H, s, CH3), 1.50 (6H, s, CH3). δC
(100 MHz, CDCl3): 180.2, 156.7, 155.5, 154.2, 154.0, 153.1,
131.8, 131.2, 129.1, 124.1, 122.2, 120.9, 116.1, 108.1, 103.1,
78.2, 37.1, 29.1, 28.1, 25.9, 21.3, 18.0. HMRS (ESI) found
483.1695, calc. 483.1399. Anal. found C 64.8, H 5.4, S, 6.5. Calc.
for C26H26O7S: C 64.7, H 5.4, S, 6.6%.
4.5.2. Characterization of 4-(5-hydroxy-8,8-dimethyl-6-(3-
methylbut-2-en-1-yl)-4-oxo-4,8-dihydropyrano[2,3-f]chromen-3-
yl)-1,2-phenylene dimethanesulfonate (8)
Yield: 58%. δH (400 MHz, CDCl3): 12.96 (1H, s, OH), 7.91
(1H, s, C=CH), 7.70 (4H, m, J 1.8, Ar-H), 7.46 (1H, m, Ar-H),
7.46 (1H, m, Ar-H), 7.35 (1H, m, Ar-H), 7.33 (4H, m, Ar-H),
6.69 (1H, d, J 9.9 Hz, C=CH), 5.61 (1H, d, J 9.9 Hz, C=CH),
5.23 (1H, m, C=CH), 3,36 (2H, d, J 7.1 Hz, CH2), 2.48 (6H, s,
CH3), 1.83 (3H, s, CH3), 1.70 (3H, s, CH3), 1.51 (6H, s, CH3). δC
(100 MHz, CDCl3): 180.8, 159.2, 157.5, 145.7, 141, 132.1, 131.7,
129.8, 128.6, 128.5, 125, 124.3, 122.1, 121.7, 28.8, 28.1, 25.9,
21.8. HMRS (ESI) found 729.2207, calc. 729.1750. Anal. found
C 64.2, H 5.0, S 8.8. Calc. for C39H36O10S2: C 64.3, H 5.0, S
8.8%.
4.4.4. Characterization of 4-(5-hydroxy-8,8-dimethyl-10-(3-
methylbut-2-en-1-yl)-4-oxo-4,8-dihydropyrano[3,2-g]chromen-3-
yl)-1,2-phenylene dimethanesulfonate (12)
Yield: 67%. δH (400 MHz, CDCl3): 12.77 (1H, s, OH), 7.98
(1H, s, C=CH), 7.74 (1H, m, Ar-H), 7.58 (2H, m, Ar-H), 6.72
(1H, d, J 9.9 Hz, C=CH), 5.64 (1H, d, J 9.9 Hz, C=CH), 5.26 (1H,
m, C=CH), 3.37(2H, d, J 7.1 Hz, CH2), 3.31 (3H, s, CH3), 3.30
(3H, s, CH3), 1.83 (3H, s, CH3), 1.70 (3H, s, CH3), 1.51 (6H, s,
CH3). δC (100 MHz, CDCl3): 180.3, 156.4, 154.6, 151.0, 132.2,
130.4, 130.2, 127.3, 122.2, 121.5, 119.3, 116.2, 115.4, 112.6,