Y. Ruland et al. / Tetrahedron 61 (2005) 8895–8903
8901
65:35, flow rateZ0.6 ml/min, UV 220 nm. Retention time
14a/14bZ4.26/2.62 min. 14c/14dZ3.66/6.37 min.
remaining mixture was then purified by inverse phase
chromatography (silica, hyperprep C18, eluant H2O/
CH3CN 55:45). Two fractions could be isolated containing
compounds 15a, 15b (0.73 g), and 15c, 15d (0.125 g).
1H NMR (400 MHz, CDCl3) d (14a,14b) 7.33–7.31 (m, 5H,
phenyl), 4.61–4.51 (m, 2H, PhCH2O), 4.29–4.20 (m, 4H,
CH2 ethyl), 4.09 (ddd, 1H, J6/7Z7.90 Hz, J6/5axZ12.35 Hz,
Rf: 0,28 (PE/AcOEt 5:5).
J6/5eqZ2.39 Hz, H6), 3.76 (dd, 1H, J9a/8Z4.42 Hz, J9a/9b
11.18 Hz, H9a), 3.63 (dd, 1H, J9b/8Z6.48 Hz, J9b/9a
11.19 Hz, H9b), 3.29–3.24 (m, 1H, H8), 3.08 (dd, 1H, J7/6
Z
Z
Z
Z
Analytical HPLC: C18, 3 mm column, eluant: H2O/CH3CN
65:35, flow rateZ0.6 ml/min, UV 220 nm. Retention time
15a/15bZ6.72/3.77 min. 15c/15dZ4.14/2.69 min.
7.77 Hz, J7/8Z4.52 Hz, H7), 2.39 (dd, 1H, J3eq/3ax
4
13.04 Hz, J3eq/5eqZ2.09 Hz, H3eq), 2.19 (td, 1H, J5eq/
3eqZJ5eq/6Z2.10 Hz, J5eq/5axZ12.90 Hz, H5eq), 2.16 (d,
1H NMR (400 MHz, CDCl3) d (15a or 15b) 7.31–7.30 (m,
5H, phenyl), 4.56 and 4.51 (2d, 2H, JZ12.00 Hz, PhCH2O),
4.24–4.18 (m, 4H, CH2 ethyl), 4.11 (ddd, 1H, J6/7Z5.48 Hz,
J6/5axZ12.15 Hz, J6/5eqZ2.37 Hz, H6), 3.73 (dd, 1H,
J9a/8Z2.97 Hz, J9a/9bZ11.71 Hz, H9a), 3.48 (dd, 1H,
J9b/8Z5.33 Hz, J9b/9aZ11.56 Hz, H9b), 3.20 (ddd, 1H,
J8/9aZJ8/7Z2.71 Hz, J8/9bZ5.19 Hz, H8), 3.03 (dd, 1H,
J3ax/3eqZ13.01 Hz, H3ax), 1.60 (t, 1H, J5ax/5eqZJ5ax/6
12.68 Hz, H5ax), 1.31–1.24 (m, 6H, CH3 ethyl).
Z
d (14c or 14d) 7.34–7.31 (m, 5H, phenyl), 4.61 and 4.52 (2d,
2H, JZ11.71 Hz, PhCH2O), 4.29–4.25 (m, 4H, CH2 ethyl),
4.03 (ddd, 1H, J6/7Z7.79 Hz, J6/5axZ11.37 Hz, J6/5eq
2.72 Hz, H6), 3.90 (dd, 1H, J9a/8Z3.39 Hz, J9a/9b
11.74 Hz, H9a), 3.55 (dd, 1H, J9b/8Z6.82 Hz, J9b/9a
11.74 Hz, H9b), 3.28–3.21 (m, 1H, H8), 3.04 (dd, 1H, J7/6
7.76 Hz, J7/8Z4.20 Hz, H7), 2.47 (d, 1H, J3ax/3eq
Z
Z
Z
Z
Z
J7/6Z5.48 Hz, J7/8Z2.23 Hz, H7), 2.39 (dd, 1H, J3eq/3ax
Z
4
13.2 Hz, J3eq/5eqZ2.22 Hz, H3eq), 2.27 (td, 1H,
J5eq/6Z4J5eq/3eqZ2.22 Hz, J5eq/5axZ12.88 Hz, H5eq), 2.15
(d, 1H, J3ax/3eqZ13.19 Hz, H3ax), 1.65 (t, 1H, J5ax/5eq
J5ax/6Z12.59 Hz, H5ax), 1.30–1.24 (m, 6H, CH3 ethyl).
Z
14.08 Hz, H3ax), 2.05–1.90 (m, 3H, H3eq, H5eq, H5ax),
1.31–1.24 (m, 6H, CH3 ethyl).
d (15b or 15a) 7.31–7.30 (m, 5H, phenyl), 4.56 and 4.51 (d,
2H, JZ12.00 Hz, PhCH2O), 4.24–4.18 (m, 4H, CH2 ethyl),
d (14d,14c) 7.34–7.31 (m, 5H, phenyl), 4.46 and 4.58 (2d,
2H, JZ11.71 Hz, PhCH2O), 4.29–4.20 (m, 4H, CH2 ethyl),
4.14 (ddd, 1H, J6/7Z4.64 Hz, J6/5axZ12.15 Hz, J6/5eq
2.51 Hz, H6), 3.76 (dd, 1H, J9a/8Z2.81 Hz, J9a/9b
11.55 Hz, H9a), 3.43 (dd, 1H, J9b/8Z5.63 Hz, J9b/9a
11.55 Hz, H9b), 3.16 (ddd, 1H, J8/9bZ5.26 Hz, J8/9a
J8/7Z2.67 Hz, H8), 2.99 (dd, 1H, J7/6Z4.37 Hz, J7/8
Z
Z
Z
Z
Z
Z
4.14 (ddd, 1H, J6/7Z7.38 Hz, J6/5axZ12.25 Hz, J6/5eq
2.37 Hz, H6), 3.67 (dd, 1H, J9a/8Z5.91 Hz, J9a/9b
11.07 Hz, H9a), 3.63 (dd, 1H, J9b/8Z6.82 Hz, J9b/9a
11.09 Hz, H9b), 3.28–3.21 (m, 1H, H8), 3.09 (dd, 1H, J7/6
7.36 Hz, J7/8Z4.48 Hz, H7), 2.46 (d, 1H, J3ax/3eq
Z
Z
Z
Z
Z
4
2.15 Hz, H7), 2.38 (dd, 1H, J3eq/3axZ13.19 Hz, J3eq/5eq
14.09 Hz, H3ax), 2.05–1.90 (m, 2H, H3eq and H5ax),
1.70 (td, 1H, J5eq/5axZ13.4 Hz, J5eq/6Z4J5eq/3eqZ2.32 Hz,
H5eq), 1.31–1.24 (m, 3H, CH3 ethyl).
2.30 Hz, H3eq), 2.27 (td, 1H, J5eq/6Z4J5eq/3eqZ2.22 Hz,
J5eq/5axZ12.88 Hz, H5eq), 2.16 (d, 1H, J3ax/3eqZ13.19 Hz,
H3ax), 1.61 (dd, 1H, J5ax/6Z12.15 Hz, J5ax/5eqZ12.88 Hz,
H5ax), 1.30–1.24 (m, 3H, CH3 ethyl).
13C NMR (63 MHz, CDCl3) d (14a,14b) 173.9, 173.7,
168.0, 169.2 (CO2Et), 137.8 (Cq phenyl), 128.5, 128.2,
127.9, 127.8, 127.7 (CH phenyl), 94.7 (C2), 73.3 and 73.1
(OCH2Ph), 70.8 and 72.1 (C4), 69.6 and 68.4 (C6), 68.2 and
68.0 (C9), 62.8, 62.7, and 62.1 (CH2 ethyl), 57.3 and 56.8
(C8), 55.7 and 54.5 (C7), 40.7, 40.5, and 36.7, 35.0 (C5 and
C3), 14.0 and 13.9 (CH3 ethyl).
d (15c or 15d) 7.31–7.23 (m, 5H, phenyl), 4.56 and 4.51 (2d,
2H, JZ11.60 Hz, PhCH2O), 4.27–4.18 (m, 5H, CH2 ethyl
and H6), 3.74 (dd, 1H, J9a/8Z2.79 Hz, J9a/9bZ11.67 Hz,
H9a), 3.43 (dd, 1H, J9b/8Z5.60 Hz, J9b/9aZ11.68 Hz, H9b),
3.13 (ddd, 1H, J8/9aZJ8/7Z2.65 Hz, J8/9bZ5.10 Hz, H8),
3.02 (dd, 1H, J7/6Z4.72 Hz, J7/8Z2.18 Hz, H7), 2.45 (d,
1H, J3eq/3axZ14.06 Hz, H3ax), 1.98–1.90 (m, 2H, H3eq and
d (14c and 14b) 173.7, 173.6, 168.8, and 169.7 (CO2Et),
137.9 and 137.6 (Cq phenyl), 128.5, 128.4, 128.0, 127.9,
127.8, 127.7 (CH phenyl), 94.8 (C2), 73.4 and 73.2
(OCH2Ph), 72.2 and 72.0 (C4), 68.1 and 68.0 (C9), 66.2
and 64.7 (C6), 62.6, 62.5 and 62.4 (CH2 ethyl), 57.3, 56.7
(C8), 55.9 and 54.5 (C7), 37.2, 36.9, 35.2 (C5 and C3), 14.1,
14.0 (CH3 ethyl).
H5ax), 1.73 (dt, 1H, J5ax/5eqZ13.4 Hz, J5eq/6Z4J5eq/3eq
Z
2.37 Hz, H5eq), 1.31–1.27 (m, 6H, CH3 ethyl).
13C NMR (100 MHz, CDCl3) d (15a or 15b) 173.5 and
169.3 (CO2Et), 137.9 (Cq phenyl), 128.6 and 127.9 (CH
phenyl), 94.8 (C2), 73.4 (OCH2Bn), 71.3 (C4), 69.6 (C9),
69.4 (C6), 62.9 (CH2 ethyl), 62.1 (CH2 ethyl), 56.9 (C8),
54.3 (C7), 40.6 (C5), 35.3 (C3), 14.1 (CH3 ethyl).
MS (DCI, NH3): 442 (MC18). IR (neat) nmax 3431 (OH),
.
3060 (CH arom.), 2983 (CH), 1738 (C]O) cmK1
d (15b or 15a) 173.5 and 169.3 (CO2Et), 137.9 (Cq phenyl),
128.6 and 127.9 (CH phenyl), 94.7 (C2), 73.4 (OCH2Bn),
71.3 (C4), 69.7 (C9), 68.5 (C6), 62.9 (CH2 ethyl), 62.1 (CH2
ethyl), 56.6 (C8), 55.1 (C7), 40.6 (C5), 35.3 (C3), 14.1 (CH3
ethyl).
Anal. Calcd for C21H28O9: C, 59.43; H, 6.60. Found: C,
59.64; H, 6.48.
2.3.2. Ethyl 2,4-dihydroxy-4-carbethoxy-6-(9-(benzyl-
oxy)-7,8-trans-epoxy)-tetrahydropyran-2-carboxylate
15a–15d. The crude product was first purified by medium
pressure silica gel chromatography (eluant petroleum ether/
ethyl acetate 6:4) affording 0.25 g of starting aldehyde. The
d (15c or 15d) 173.9 and 168.6 (CO2Et), 137.8 (Cq phenyl),
128.4, 128.0, 127.9, 127.8 (CH phenyl), 94.9 (C2), 73.2
(OCH2Bn), 72.2 (C4), 69.5 (C9), 66.1 (C6), 62.6 (CH2