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L. Environ. Sci. Technol. 2005, 39, 2990.
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1384.
(300 MHz, CDCl3) d 7.79 (1H, d, J = 2.3 Hz), 7.51 (1H, d, J = 2.3 Hz), 7.42–7.36
(1H, dd, J = 2.3 and 8.5 Hz), 6.91 (1H, d, J = 2.3 Hz), 6.74 (1H, d, J = 8.5 Hz), 4.34
(2H, t), 3.56 (2H, t). FABMS (m/z) 608 [M+].
1-(2-(3-Bromopropoxy)-3,5-dibromophenoxy)-2,4-dibromobenzene (K): 1H NMR
(300 MHz, CDCl3) d 7.78 (1H, d, J = 2.3 Hz), 7.50 (1H, d, J = 2.3 Hz), 7.40–7.35
(1H, dd, J = 2.0 and 8.7 Hz), 6.91 (1H, d, J = 2.3 Hz), 6.73 (1H, d, J = 8.7 Hz), 4.19
(2H, t), 3.57 (2H, t), 2.31–2.18 (2H, m). FABMS (m/z) 623 [M+].
1-(2-(4-Bromobutoxy)-3, 5-dibromophenoxy)-2,4-dibromobenzene (L): 1H NMR
(300 MHz, CDCl3) d 7.78 (1H, d, J = 2.3 Hz), 7.50 (1H, d, J = 2.3 Hz), 7.39–7.34
(1H, dd, J = 2.3 and 8.9 Hz), 6.96 (1H, d, J = 2.3 Hz), 6.68 (1H, d, J = 8.9 Hz), 4.05
(2H, t), 3.40 (2H, t), 2.09–1.78 (4H, m). FABMS (m/z) 637 [M+].
1-(2-(5-Bromopentyloxy)-3,5-dibromophenoxy)-2,4-dibromobenzene (M): 1H
NMR (300 MHz, CDCl3)
d 7.77 (1H, d, J = 2.2 Hz), 7.52 (1H, d, J = 2.2 Hz),
7.37–7.34 (1H, dd, J = 2.2 and 8.3 Hz), 6.99 (1H, d, J = 2.2 Hz), 6.67 (1H, d,
J = 8.3 Hz), 4.02 (2H, t), 3.33 (2H, t), 1.91–1.81 (2H, m), 1.77–1.68 (2H, m),
1.57–1.50 (2H, m); 13C NMR (75 MHz, CDCl3) d 152.12, 149.50, 146.85, 135.91,
131.64, 131.11, 122.33, 119.48, 119.39, 116.63, 116.60, 114.04, 73.60, 33.39,
32.29, 29.06, 24.43. FABMS (m/z) 651 [M+].
24. Calcul, L.; Chow, R.; Oliver, A. G.; Tenney, K.; White, K. N.; Wood, A. W.; Fiorilla,
C.; Crews, P. J. Nat. Prod. 2009, 72, 443.
25. Sharma, G. M.; Vig, B.; Burkholder, P. R. Proc. Marine Technol. Soc. 1969, 307.
26. Marsh, G.; Stenutz, R.; Bergman, A. Eur. J. Org. Chem. 2003, 2566.
27. Rancesconi, K.; GhisaIberti, E. L. Aust. J. Chem. 1985, 38, 1271.
28. The sponge Dysidea herbacea was collected from the Mandapam coast in the
Gulf of Mannar, Tamilnadu, India. A voucher specimen (IIC-631) was deposited
at the National Institute of Oceanography, Goa, India.
1-(2-(6-Bromohexyloxy)-3,5-dibromophenoxy)-2,4-dibromobenzene (N): 1H NMR
(300 MHz, CDCl3) d 7.77 (1H, d, J = 2.3 Hz), 7.51 (1H, d, J = 2.3 Hz), 7.38–7.33
(1H, dd, J = 2.3 and 8.5 Hz), 7.00 (1H, d, J = 2.3 Hz), 6.66 (1H, d, J = 8.5 Hz), 4.00
(2H, t), 3.43 (2H, t), 1.89–1.64 (4H, m), 1.45–1.39 (4H, m). FABMS (m/z) 665
[M+].
2-(2-(2,4-Dibromophenoxy)-4,6-dibromophenoxy)-1-phenylethanone (O): 1H
29. The freshly collected sponge (1 kg) was soaked in methanol at the site of
collection until workup. The resultant initial aqueous methanol extract was
decanted from the sponge material and the sponge material was re-extracted
with dichloromethane/methanol (1:1, 3 ꢀ 1.5 L) by percolation at room
temperature. The combined extract including the initial methanol extract
NMR (300 MHz, CDCl3) d 7.88 (2H, d, J = 8.3 Hz), 7.70 (1H, d, J = 2.2 Hz),
7.57–7.52 (2H, m), 7.43–7.35 (3H, m), 6.88 (1H, d, J = 2.2 Hz), 6.77 (1H, d,
J = 8.3 Hz), 5.32 (2H, s). FABMS (m/z) 620 [M+].
2-(2-(2,4-Dibromophenoxy)-4,6-dibromophenoxy)-1-(4-chlophenyl)-ethanone
(P): 1H NMR (300 MHz, CDCl3) d 7.86 (2H, d, J = 8.3 Hz), 7.72 (1H, d, J = 2.2 Hz),
7.52 (1H, m), 7.41–7.37 (3H, m), 6.88 (1H, d, J = 2.2 Hz), 6.76 (1H, d, J = 8.3 Hz),
5.24 (2H, s). FABMS (m/z) 654 [M+].
was concentrated under reduced pressure to obtain
a crude aqueous
suspension, which was extracted with ethyl acetate. The concentrated ethyl
acetate extract (10 g) was subjected to gel filtration chromatography on
Sephadex LH-20 followed by silica gel chromatography eluting with hexane,
hexane–ethyl acetate mixtures and finally with ethyl acetate.
31. Typical experimental procedure for the preparation of N-alkyl piperazine derivatives
of M: To a mixture of M (1 mmol) and anhydrous potassium carbonate (2 mmol)
in 20 mL acetonitrile, N-alkylated piperazine was added. The mixture was
refluxed under nitrogen for 6 h. After completion of the reaction, the reaction
mixture was brought to room temperature, poured into ice water and washed
with methylene chloride (2 ꢀ 10 mL). The combined organic layers were dried
over anhydrous sodium sulfate and concentrated under vacuum. The residue
was purified by column chromatography on silica gel (60–120 mesh) to give the
corresponding N-alkylpiperazine derivatives Q–X.
2-(20,40-Dibromophenoxy)-4,6-dibromophenol (HO-PBDE): Afforded HO-PBDE
(3.5 g) as a white solid, mp 88–90 °C, Rf: 0.60 (Hexane/Ethyl acetate, 9:1). 1H
NMR (300 MHz, CDCl3) d 7.81 (1H, d, J = 2.2 Hz), 7.46 (1H, d, J = 2.2 Hz), 7.46–
7.42 (1H, dd, J = 2.2 and 8.3 Hz), 6.90 (1H, d, J = 8.3 Hz), 6.80 (1H, d, J = 2.2 Hz),
5.95 (1H, br s); 13C NMR (75 MHz, CDCl3) d 151.49, 144.31, 143.68, 136.31,
131.94, 130.16, 121.39, 119.78, 118.01, 115.46, 111.75, 110.87. FABMS (m/z)
502 [M+].
1-(5-(2-(2,4-Dibromophenoxy)-4,6-dibromophenoxy)pentyl)-4-methylpiperazine
(Q): 1H NMR (300 MHz, CDCl3) d 7.77 (1H, d, J = 2.2 Hz), 7.51 (1H, d, J = 2.2 Hz),
7.40–7.36 (1H, dd, J = 2.2 and 8.3 Hz), 6.97 (1H, d, J = 2.2 Hz), 6.70 (1H, d,
J = 8.3 Hz), 4.01 (2H, t), 2.90 (8H, t), 2.60 (2H, t), 2.57 (3H s), 1.76–1.67 (2H, m),
1.66–155 (2H, m), 1.45–1.35 (2H, m) 13C NMR (75 MHz, CDCl3) d 152.31, 149.58,
147.02, 136.02, 131.78, 131.31, 122.48, 119.55, 116.70, 116.49, 114.15, 73.72,
57.61, 53.56, 51.40, 44.81, 29.63, 25.49, 23.52. FABMS (m/z) 670 [M+].
tert-Butyl 4-(5-(2-(2,4-dibromophenoxy)-4,6-dibromophenoxy)pentyl)piperazine-
1-carboxylate (R): 1H NMR (300 MHz, CDCl3) d 7.76 (1H, d, J = 2.2 Hz), 7.51 (1H,
d, J = 2.2 Hz), 7.37–7.33 (1H, dd, J = 2.2 and 9.0 Hz), 6.99 (1H, d, J = 2.2 Hz), 6.66
(1H, d, J = 9.0 Hz), 4.00 (2H, t), 3.38 (4H, t), 2.32 (4H, t), 2.26 (2H t), 1.75–1.66
(2H, m), 1.52–1.33 (4H, m), 1.45 (9H, m); 13C NMR (75 MHz, CDCl3) d 155.44,
152.28, 149.63, 146.99, 136.01, 131.80, 131.28, 122.43, 119.67, 119.47, 116.70,
116.43, 114.18, 79.93, 73.89, 58.28, 52.68, 29.68, 28.35, 25.63, 23.64. FABMS (m/
z) 756 [M+].
1-(5-(2-(2,4-Dibromophenoxy)-4,6-dibromophenoxy)pentyl)-4-phenylpiperazine
(S): 1H NMR (300 MHz, CDCl3) d 7.77 (1H, d, J = 2.2 Hz), 7.51 (1H, d, J = 2.2 Hz),
7.38–7.37 (1H, dd, J = 2.2 and 8.6 Hz), 7.26–7.20 (2H, m), 6.97 (1H, d, J = 2.2 Hz),
6.90–6.81 (3H, m), 6.68 (1H, d, J = 8.6 Hz), 4.03 (2H, t), 3.22 (4H, t), 2.64 (4H, t),
2.41 (2H t), 1.78–1.69 (2H, m), 1.62–152 (2H, m), 1.45–1.35 (2H, m); 13C NMR
(75 MHz, CDCl3) d 152.45, 151.13, 149.68, 147.23, 136.10, 131.82, 131.43,
129.11, 122.63, 119.90, 119.55, 116.75, 116.49, 116.20, 114.23, 74.01, 58.44,
53.09, 48.88, 29.76, 26.19, 23.85. FABMS (m/z) 732 [M+].
30. Typical experimental procedure for the preparation of alkyl derivatives of HO-
PBDE: To a mixture of HO-PBDE (1 mmol) and anhydrous potassium carbonate
(2 mmol) in 20 mL acetone, alkyl halide (1 mmol) was added. The mixture was
refluxed under nitrogen atmosphere for 6 h. After completion of the reaction
potassium carbonate was filtered and washed with excess acetone (2 ꢀ 50 mL).
The combined acetone layers were concentrated under vacuum. The residue
was purified by column chromatography on silica gel (60–120 mesh) to give
the corresponding ether A–P.
1-(3,5-Dibromo-2-methoxyphenoxy)-2,4-dibromobenzene
(A):
1H
NMR
(300 MHz, CDCl3) d 7.77 (1H, d, J = 2.2 Hz), 7.50 (1H, d, J = 2.2 Hz), 7.38–7.34
(1H, dd, J = 2.2 and 8.3 Hz), 6.94 (1H, d, J = 2.2 Hz), 6.71 (1H, d, J = 8.3 Hz), 3.87
(3H, s). FABMS (m/z) 516 [M+].
2-(2,4-Dibromophenoxy)-4,6-dibromophenylacetate (B): 1H NMR (300 MHz,
CDCl3) d 7.71 (1H, d, J = 2.3 Hz), 7.45 (1H, d, J = 2.3 Hz), 7.37–7.32 (1H, dd,
J = 2.3 and 8.5 Hz), 6.83 (1H, d, J = 8.5 Hz), 6.76 (1H, d, J = 2.3 Hz), 2.25 (3H, s).
FABMS (m/z) 544 [M+].
1-(2-(Allyloxy)-3,5-dibromophenoxy)-2,4-dibromobenzene
(C):
1H
NMR
(300 MHz, CDCl3) d 7.77 (1H, d, J = 2.2 Hz), 7.51 (1H, d, J = 2.2 Hz), 7.40–7.34
(1H, dd, J = 2.2 and 8.0 Hz), 6.94 (1H, d, J = 2.2 Hz), 6.71 (1H, d, J = 8.0 Hz), 6.13–
5.93 (1H, m), 5.36–5.19 (2H, m), 4.58 (2H, d). FABMS (m/z) 542 [M+].
1-(2-(Allyloxy)-3,5-dibromophenoxy)-2,4-dibromobenzene
(D):
1H
NMR
(300 MHz, CDCl3) d 7.76 (1H, d, J = 2.2 Hz), 7.50 (1H, d, J = 2.2 Hz), 7.41–7.33
(1H, dd, J = 2.2 and 8.0 Hz), 6.93 (1H, d, J = 2.2 Hz), 6.71 (1H, d, J = 8.0 Hz), 4.68
(2H, s), 2.51 (1H, s). FABMS (m/z) 540 [M+].
1-(5-(2-(2,4-Dibromophenoxy)-4,6-dibromophenoxy)pentyl)-4-(2-
methoxyphenyl)-piperazine (T): 1H NMR (300 MHz, CDCl3)
d 7.70 (1H, d,
2-(2-(2,4-Dibromophenoxy)-4,6-dibromophenoxy)ethanol
(E):
1H
NMR
J = 2.2 Hz), 7.44 (1H, d, J = 2.2 Hz), 7.32–7.28 (1H, dd, J = 2.2 and 8.6 Hz), 6.95–
6.77 (5H, m), 6.62 (1H, d, J J = 8.6 Hz), 3.97 (2H, t), 3.79 (3H, s), 3.02 (4H, t), 2.58
(300 MHz, CDCl3) d 7.79 (1H, d, J = 2.4 Hz), 7.51 (1H, d, J = 2.4 Hz), 7.42–7.37
(1H, dd, J = 2.4 and 8.8 Hz), 6.90 (1H, d, J = 2.4 Hz), 6.75 (1H, d, J = 8.8 Hz), 4.20
(2H, t), 3.82 (2H, t), 2.20 (1H, br s). LCMS (m/z) 547 [M++H].
(4H, t), 2.32 (2H, t), 1.72–1.63 (2H, m), 1.53–143 (2H, m), 1.38–1.30 (2H, m). 13
C
NMR (75 MHz, CDCl3) d 152.31, 149.69, 147.11, 141.31, 136.04, 131.80, 131.27,
122.84, 122.42, 119.69, 119.54, 118.18, 116.73, 116.34, 114.23, 111.12, 74.13,
58.58, 53.32, 53.39, 50.53, 29.92, 29.66, 26.49, 23.86. FABMS (m/z) 762 [M+].
1-(5-(2-(2,4-Dibromophenoxy)-4,6-dibromophenoxy)pentyl)-4-
3-(2-(2,4-Dibromophenoxy)-4,6-dibromophenoxy)propan-1-ol (F): 1H NMR
(300 MHz, CDCl3) d 7.78 (1H, d, J = 2.4 Hz), 7.50 (1H, d, J = 2.4 Hz), 7.40–7.35
(1H, dd, J = 2.4 and 8.8 Hz), 6.92 (1H, d, J = 2.4 Hz), 6.73 (1H, d, J = 8.8 Hz), 4.20
(2H, t), 3.80 (2H, t), 2.01–1.89 (2H, m) 1.76 (1H, br s). FABMS (m/z) 560 [M+].
cinnamylpiperazine (U): 1H NMR (300 MHz, CDCl3) d 7.69 (1H, d, J = 2.2 Hz), 7.43
(1H, d, J = 2.2 Hz), 7.31–7.16 (6H, m), 6.87 (1H, d, J = 2.2 Hz), 6.62 (1H, d,
J = 8.6 Hz), 6.48 (1H, d, J = 15.8 Hz), 6.19–6.09 (1H, m), 3.95 (2H, t), 3.30 (1H, t),
3.20 (2H, t), 2.76 (6H, t), 2.53 (2H, t), 2.29 (1H, t), 1.98–188 (1H, m), 1.70–1.51
(4H, m), 1.38–1.28 (1H, m). 13C NMR (75 MHz, CDCl3) d 152.19, 149.63, 146.86,
136.28, 135.99, 134.57, 131.81, 131.20, 128.54, 127.81, 126.37, 124.28, 122.29,
119.75, 119.45, 116.73, 116.44, 114.21, 113.99, 73.72, 60.33, 55.86, 52.29, 51.42,
49.35, 29.54, 25.19, 23.49. FABMS (m/z) 772 [M+].
1-(2,4-Dibrophenoxy)-2-(benzyloxy)-3,5-dibromobenzene
(G):
1H
NMR
(300 MHz, CDCl3) d 7.76 (1H, d, J = 2.3 Hz), 7.51 (1H, d, J = 2.3 Hz), 7.40–7.21
(6H, m), 6.96 (1H, d, J = 2.3 Hz), 6.68 (1H, d, J = 8.5 Hz), 5.06 (2H, s). FABMS
(m/z) 592 [M+].
Ethyl 2-(2-(2,4-dibrophenoxy)-4,6-dibromophenoxy)propanoate (H): 1H NMR
(300 MHz, CDCl3) d 7.78 (1H, d, J = 2.2 Hz), 7.50 (1H, d, J = 2.2 Hz), 7.43–7.39
(1H, dd, J = 2.2 and 9.0 Hz), 6.82 (1H, d, J = 2.2 Hz), 6.77 (1H, d, J = 9.0 Hz), 4.99–
4.92 (1H, q), 4.18–4.11 (2H, q), 1.59 (3H, d), 1.21 (3H, t). FABMS (m/z) 602 [M+].
2-(2-(2,4-Dibromophenoxy)-4,6-dibromophenoxy)-4,4-dimethyl-3-oxo-
pentanenitrile (I):1H NMR (300 MHz, CDCl3) d 7.77 (1H, d, J = 2.2 Hz), 7.51 (1H,
d, J = 2.2 Hz), 7.43–7.38 (1H, dd, J = 2.2 and 8.6 Hz), 6.82 (1H, d, J = 2.2 Hz), 6.77
(1H, d, J = 8.6 Hz), 5.56 (1H, s), 1.66 (9H, s). FABMS (m/z) 625 [M+].
1-(2-(2-Bromoethoxy)-3,5-dibromophenoxy)-2,4-dibromobenzene (J): 1H NMR
tert-Butyl
4-(5-(2-(2,
4-Dibromophenoxy)-4,6-dibromophenoxy)pentyl)-1,4-
diazepane-1-carboxylate (V): 1H NMR (300 MHz, CDCl3)
d
7.77 (1H, d,
J = 2.2 Hz), 7.51 (1H, d, J = 2.2 Hz), 7.39–7.35 (1H, dd, J = 2.2 and 8.3 Hz), 6.97
(1H, d, J = 2.2 Hz), 6.70 (1H, d, J = 8.3 Hz), 4.03 (2H, t), 3.48 (2H, t), 3.43 (2H, t),
2.61 (2H, t), 2.58 (2H, t), 2.42 (2H t), 1.85–1.77 (2H, m), 1.74–166 (2H, m), 1.46
(9H, s), 143–1.41 (4H, m). 13C NMR (75 MHz, CDCl3) d 155.45, 152.25, 149.63,