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4.1.9. 2-(tert-Butyldiphenylsilyloxyimino)-3-(3,5-di-
bromo-4-hydroxyphenyl)propionic acid (12d, RZ
TBDPS). In the same procedure as 12a, 11 (0.10 g,
0.55 mmol) was converted to 12d (0.14 g, 44%). Colorless
oil. FAB MS: m/z 590/592/594 (MCH)C. HR-FAB MS: m/z
591.9978, calcd for C25H2679Br81BrNO4Si. Found: 591.9957.
IR nmax (KBr) cmK1: 3488, 3051, 1703. 1H NMR (acetone-d6)
d: 7.69–7.67 (4H, m), 7.56 (2H, s), 7.47–7.39 (6H, m), 4.06
(2H, s), 1.11 (9H, s). 13C NMR (acetone-d6) d: 164.8, 156.7,
150.3, 136.1 (4C), 133.6 (2C), 133.3 (2C), 131.7, 130.9 (2C),
128.6 (4C), 111.4 (2C), 30.2, 27.3 (3C), 19.9.
imino)propionic acid (13d, RZTBDPS). As the same
procedure in the synthesis of 2, 12d (26 mg, 0.043 mmol)
was converted to 13d (15 mg, 65%). Colorless oil. ESI-Q-
TOF MS: m/z 1119/1121/1123/1125 (MCNa)C. HR-ESI-
Q-TOF MS: m/z 1121.0298, calcd for C50H4779Br281BrN2O8-
Si2Na. Found: 1121.0313. IR nmax (KBr) cmK1: 3072, 1697,
1658. 1H NMR (acetone-d6) d: 7.86 (1H, d, JZ2.5 Hz), 7.73
(2H, s), 7.70–7.66 (8H, m), 7.46–7.38 (12H, m), 6.18 (1H, d,
JZ2.5 Hz), 4.16 (2H, s), 3.83 (1H, d, JZ20.0 Hz), 3.49
(1H, d, JZ20.0 Hz), 1.09 (9H, s), 1.08 (9H s). 13C NMR
(acetone-d6) d: 165.9, 164.7, 156.0, 153.1, 148.3, 148.3,
147.0, 146.9, 138.8, 136.2 (4C), 136.2 (4C), 134.7, 133.2,
133.1 (2C), 131.1 (4C), 129.7, 129.0, 128.7 (4C), 128.6
(4C), 124.1, 120.0, 117.8 (2C), 79.3, 35.4, 30.3, 27.4 (3C),
27.2 (3C), 19.9 (2C).
4.1.10. 2-Benzyloxyimino-3-[4-(3-benzyloxyimino-9-
bromo-2,8-dioxo-1-oxaspiro[4.5]deca-6,9-dien-7-yloxy)-
3,5-dibromophenyl]propionic acid (13a, RZBn). As the
same procedure in the synthesis of 2, 12a (332 mg,
0.75 mmol) was converted to 13a (152 mg, 52%). White
powder. FAB MS: m/z 801/803/805/807 (MCH)C. HR-
FAB MS: m/z 804.9042, calcd for C32H2479Br81Br2N2O8.
Found: 804.9050. IR nmax (KBr) cmK1: 3065, 3036, 1784,
4.1.14. tert-Butyl (2-{4-[5-(2-aminoethyl)-3-bromo-2-
hydroxyphenoxy]-3,5-dibromophenyl}ethyl)carbamate
(16). To a solution of 2 (0.60 g, 0.92 mmol) in THF
(20 mL), Na2S2O4 (0.96 g, 5.5 mmol) in H2O (6.0 mL) was
added and stirred for 10 min at rt. Brine was added and
extracted with AcOEt. The organic phase was dried over
MgSO4, filtered, and concentrated in vacuo. The residue
was treated with n-hexane, and the precipitate was collected
by filtration to give 16 (0.59 g, quant.) as a white powder.
FAB MS: m/z 607/609/611/613 (MCH)C. HR-FAB MS:
m/z 608.9422, calcd for C21H2679Br281BrN2O4. Found:
608.9419. IR nmax (KBr) cmK1: 3522, 3335, 1680. 1H
NMR (DMSO-d6) d: 7.87 (1H, br s), 7.62 (2H, s), 7.11 (1H,
d, JZ1.5 Hz), 6.94 (1H, t, JZ6.0 Hz), 6.11 (1H, d, JZ
1.5 Hz), 3.19 (2H, q, JZ6.0 Hz), 2.83 (2H, t, JZ7.5 Hz),
2.73 (2H, t, JZ6.0 Hz), 2.62 (2H, t, JZ7.5 Hz), 1.34 (9H,
s). 13C NMR (DMSO-d6) d: 155.5, 146.0, 144.9, 142.7,
140.7, 133.4 (2C), 129.0, 126.1, 117.2 (2C), 112.6, 110.6,
77.5, 40.6, 40.3, 34.0, 32.4, 28.2 (3C).
1
1695, 1658. H NMR (DMSO-d6) d: 13.37 (1H, br s), 7.94
(1H, d, JZ2.5 Hz), 7.51 (2H, s), 7.37–7.32 (10H, m), 6.29
(1H, d, JZ2.5 Hz), 5.27 (4H, s), 3.84 (2H, s), 3.29 (1H, d,
JZ19.5 Hz), 2.94 (1H, d, JZ19.5 Hz). 13C NMR (DMSO-d6)
d: 171.9, 164.0, 163.2, 149.8, 148.4, 146.4, 145.4, 144.9, 137.3,
136.6, 136.5, 133.2 (2C), 128.5, 128.4 (4C), 128.2 (2C), 128.1
(2C), 122.1(2C),120.2,116.5(2C), 78.2, 77.3,76.9,33.8,29.6.
4.1.11. 3-[4-(9-Bromo-3-methoxyimino-2,8-dioxo-1-
oxaspiro[4.5]deca-6,9-dien-7-yloxy)-3,5-dibromo-
phenyl]-2-(methoxyimino)propionic acid (13b, RZMe).
As the same procedure in the synthesis of 2, 12b (0.30 g,
0.83 mmol) was converted to 13b (0.16 g, 61%). White
powder. FAB MS: m/z 649/651/653/655 (MCH)C. HR-
FAB MS: m/z 650.8437, calcd for C20H1679Br281BrN2O8.
Found: 650.8463. IR nmax (KBr) cmK1: 3231, 3061, 1776,
1703. 1H NMR (acetone-d6) d: 9.86 (1H, br s), 7.79 (1H, d,
JZ2.5 Hz), 7.58 (2H, s), 6.19 (1H, d, JZ2.5 Hz), 4.06 (3H,
s), 4.02 (3H, s), 3.88 (2H, s), 3.42 (1H, d, JZ19.5 Hz), 3.17
(1H, d, JZ19.5 Hz). 13C NMR (acetone-d6) d: 172.4, 164.3,
163.6, 149.7, 148.2, 146.9, 146.7, 146.0, 138.4, 134.6 (2C),
124.1, 120.1, 117.6 (2C), 79.0, 64.3, 63.9, 34.8, 30.2.
4.1.15. tert-Butyl (2-{4-[5-(2-{2-benzyloxyimino-3-[4-(3-
benzyloxyimino-9-bromo-2,8-dioxo-1-oxaspiro[4.5]-
deca-6,9-dien-7-yloxy)-3,5-dibromophenyl]propionyl-
amino}ethyl)-3-bromo-2-hydroxyphenoxy]-3,5-di-
bromophenyl}ethyl)carbamate (17). To a stirred solution
of 13a (8.8 mg, 0.010 mmol), 16 (7.0 mg, 0.010 mmol), and
HOBt (1.7 mg, 0.011 mmol) in THF (0.10 mL), EDCI
(2.7 mg, 0.010 mmol) was added at 0 8C. The reaction
mixture was stirred for 6 h. HCl (5%) was added and
aqueous phase was extracted with AcOEt. The organic
phase was washed with brine, dried over MgSO4, filtered,
and concentrated in vacuo. The residue was purified by SiO2
column (CHCl3) to give 17 (13.2 mg, 82%) as a white
powder. ESI-Q-TOF MS: m/z 1411/1413/1415/1417/1419/
1421/1423 (MCNa)C. HR-ESI-Q-TOF MS: m/z
1416.8100, calcd for C53H4679Br381Br3N4O11Na. Found:
1416.8112. IR nmax (KBr) cmK1: 3414, 2976, 1784, 1697,
1666. 1H NMR (DMSO-d6) d: 9.93 (1H, s), 8.12 (1H, t, JZ
5.5 Hz), 7.95 (1H, d, JZ2.5 Hz), 7.61 (2H, s), 7.51 (2H, s),
7.37–7.32 (10H, m), 7.05 (1H, s), 6.90 (1H, t, JZ5.5 Hz),
6.28 (1H, d, JZ2.5 Hz), 6.07 (1H, s), 5.28 (2H, s), 5.24 (2H,
s), 3.79 (2H, s), 3.30 (1H, d, JZ19.5 Hz), 3.22–3.19 (4H,
m), 2.95 (1H, d, JZ19.5 Hz), 2.73 (2H, t, JZ5.0 Hz), 2.54
(2H, t, JZ5.0 Hz), 1.33 (9H, s). 13C NMR (DMSO-d6) d:
171.8, 163.2, 161.8, 155.5, 151.0, 148.3, 146.4, 146.0,
145.2, 144.9, 144.7, 142.0, 140.6, 137.4 (2C), 136.5 (4C),
133.4 (2C), 130.8, 128.4 (4C), 128.3, 128.2 (2C), 128.1
4.1.12. 3-{4-[9-Bromo-2,8-dioxo-3-(tetrahydropyran-2-
yloxyimino)-1-oxaspiro[4.5]deca-6,9-dien-7-yloxy]-3,5-
dibromophenyl}-2-(tetrahydropyran-2-yloxyimino)pro-
pionic acid (13c, RZTHP). As the same procedure in the
synthesis of 2, 12c (657 mg, 1.50 mmol) was converted to
13c (249 mg, 42%) as a mixture of four diastereomers.
White powder. FAB MS: m/z 809/811/813/815 (MCNa)C.
IR nmax (KBr) cmK1: 2947, 1695, 1660. 1H NMR (acetone-
d6) d: 7.86, 7.82 (1H, both d, JZ2.5 Hz), 7.70 (2H, s), 6.23–
6.17 (1H, m), 5.41–5.38 (2H, m), 3.97–3.86 (2H, m), 3.80–
3.69 (1H, m), 3.63–3.50 (4H, m), 3.33–3.22 (1H, m), 1.87
(12H, m). 13C NMR (DMSO-d6) d: 172.4, 164.5, 163.6,
150.7, 148.3, 148.2, 147.4, 147.0, 146.8, 138.6, 134.9,
133.8, 124.1, 120.2, 117.6, 103.2, 103.1, 102.8, 102.7, 79.1
(2C), 62.9, 62.7, 62.5, 62.4, 34.9, 34.8, 30.7, 29.0, 25.7,
19.6, 19.5, 19.4, 19.3.
4.1.13. 3-{4-[9-Bromo-3-(tert-butyldiphenylsilyloxy-
imino)-2,8-dioxo-1-oxaspiro[4.5]deca-6,9-dien-7-yloxy]-
3,5-dibromophenyl}-2-(tert-butyldiphenylsilyloxy-