M. Boultadakis-Arapinis et al.
600
ε-lactone: Yield: 51%. TLC analysis: Rf = 0.16 (silica, cyclohexane/ethyl acetate
3:1). 1H NMR (300 MHz, CDCl3): δ (ppm) 7.38 (m, 10H, Harom.), 5.62 (s, 1H,
H-7), 5.01 (s, 1H, H-1), 4.89 (d, J = 3.8 Hz, 1H, H-2), 4.81 (dd, J = 9.2, 5.2
Hz, 1H, CHPh), 4.33 (dd, J = 9.0, 3.3 Hz, 1H, H-6eq.), 4.26 (dd, J = 9.2,
3.8 Hz, 1H, H-3), 4.05 (t, J = 9.2 Hz, 1H, H-4), 3.99–3.82 (m, 2H, H-5, H-
6ax.), 3.63 (dd, J = 15.6, 9.2 Hz, 1H, H-8), 3.47 (s, 3H, OMe), 3.15 (dd, J =
15.6, 5.2 Hz, 1H, H-8ꢁ). 13C NMR (75 MHz, CDCl3): δ (ppm) 169.1 (C=O),
142.0 (Cquat. arom.), 137.2 (Cquat. arom.), 129.1 (CHarom.), 128.7 (CHarom.), 128.3
(CHarom.), 128.1 (CHarom.), 126.2 (CHarom.), 125.7 (CHarom.), 101.9 (C-7), 99.1
(C-1), 77.4 (C-4), 74.4 (C-2), 74.3 (C-3), 71.2 (CHPh), 68.7 (C-6), 62.3 (C-
5), 50.7 (OMe), 44.3 (C-8). IR (film): 2920; 1449; 1496; 1455; 1367; 1301;
1246; 1218; 1134; 1093; 1040; 919; 848; 754; 699; 669. HRMS calculated for
20
C23H24O7Na: 435.1420, found: 435.1412, [α]D = –69 (c = 1.0, CHCl3).
18: Yield: 90%. TLC analysis: Rf = 0.60 (silica, cyclohexane/ethyl acetate 2:1).
1H NMR (300 MHz, 50◦C, CDCl3) δ (ppm): 7.51–7.31 (m, 5H, Harom.), 5.57
(s, 1H, H-7), 5.31 (dd, J = 10.3, 6.1 Hz, 1H, H-3), 4.47 (d, J = 6.1 Hz,1H,
H-2), 4.42–4.33 (m, 1H, H-6), 4.03–3.91 (m, 1H, H-4), 3.85–3.71 (m, 2H,
H-5, H-6), 3.42 (s, 3H, OMe), 2.92 (d, J = 17.1 Hz, 1H, H-8), 2.69 (d,
J = 17.1 Hz, 1H, H-8ꢁ), 1.24 (s, 9H, (CH3)3C). 13C NMR (75 MHz, CDCl3)
δ (ppm): 177.0 (C=O), 171.0 (C=O), 136.6 (Cquat. arom.), 129.1 (CHarom.), 128.3
(CHarom.), 125.9 (CHarom.), 103.9 (C-1), 101.4 (C-7), 82.0 (C-2), 76.1 (C-4),
71.9 (C-3), 68.9 (C-6), 66.4 (C-5), 50.7 (OMe), 38.8 ((CH3)3C), 36.5 (C-8), 27.0
((CH3)3C). IR (film): 2971; 1798; 1740; 1457; 1375; 1277; 1135; 1078; 1031;
699. MS: m/z = 429 (MNa+). HRMS calculated for C21H26O8Na: 429.1520,
20
found: 429.1521. [α]D = +1 (c = 1.0, CHCl3).
19: Yield: 35%. TLC analysis: Rf = 0.34 (silica, cyclohexane/ethyl acetate 3:1).
1H NMR (300 MHz, CDCl3): δ (ppm) 7.52–7.31 (m, 10H, Harom.), 5.63 (s, 1H,
H-7), 4.85 (s, 2H, CH2Ph), 4.56 (d, J = 5.6 Hz, 1H, H-2), 4.37 (dd, J = 10.3,
4.8 Hz, 1H, H-6eq.), 3.99 (t, J = 9.7 Hz, 1H, H-4), 3.87–3.74 (m, 2H, H-3, H-
6ax.), 3.67 (dt, J = 9.7, 4.8 Hz, 1H, H-5), 3.40 (s, 3H, OMe), 2.86 (d, J =
17.2 Hz, 1H, H-8), 2.69 (d, J = 17.2 Hz, 1H, H-8ꢁ). 13C NMR (75 MHz,
CDCl3): δ (ppm) 171.6 (C=O), 137.4 (Cquat. arom.), 136.9 (Cquat. arom.), 129.2
(CHarom.), 128.5 (CHarom.), 128.4 (CHarom.), 128.0 (CHarom.), 126.1 (CHarom.),
103.9 (C-1), 101.6 (C-7), 83.9 (C-2), 78.8 (C-3), 78.2 (C-4), 73.7 (CH2Ph), 68.9
(C-6), 66.4 (C-5), 50.7 (OMe), 36.8 (C-8). IR (film): 2933; 1793; 1605; 1497;
1454; 1372; 1331; 1268; 1245; 1213; 1170; 1091; 1028; 916; 890; 752; 698;
20
601. HRMS calculated for C23H24O7Na: 435.1420, found: 435.1415. [α]D
+5 (c = 1.0, CHCl3).
=
20: Yield: 92%. TLC analysis: Rf = 0.49 (silica, cyclohexane/ethyl acetate 3:1).
1H NMR (300 MHz, CDCl3): δ (ppm) 7.57–7.32 (m, 5H; Harom.), 5.58 (s, 1H,
H-7), 4.47–4.29 (m, 2H, H-2, H-6), 3.89 (dd, J = 9.6, 5.8 Hz, 1H, H-3),