Rf 0.37 (EtoAc/Hexane, 1 : 2); 1H NMR (400 MHz, CDCl3):
dppm 7.29–7.22 (m, 10H), 4.47 (s, 4H), 3.81–3.79 (m, 2H),
3.55–3.50 (m, 4H), 2.09 (s, 2H); 13C NMR (100 MHz, CDCl3):
dppm 137.7, 128.2, 127.6, 127.5, 73.1, 71.5, 70.4; FT-IR (KBr)
n 3304, 3029, 2919, 2862, 1638, 1454, 1386, 1362, 1261, 1090, 949,
907, 804, 750, 734, 696, 610 cmꢀ1; HR-MS m/z (%): calcd. for
C18H22O4Na+ [M + Na]+: 325.1410, found: 325.1420.
2.40–2.31 (m, 4H), 1.65–1.61 (m, 4H), 1.28–1.23 (m, 16H),
0.85 (m, 6H); 13C NMR (100 MHz, CDCl3): dppm 173.2, 73.3,
62.4, 34.4, 34.2, 31.8, 29.2, 29.15, 29.1, 29.0, 25.1, 24.8, 22.7,
14.2; FT-IR (KBr) n 3434, 2961, 2926, 2854, 1733, 1638,
1461, 1261, 1095, 1024 cmꢀ1; HR-MS m/z (%): calcd. for
C20H38O6Na+ [M + Na]+: 397.2561, found: 397.2562.
[(2S,3S)-3-[(hexadecanoyloxy)methyl]-1,4-dioxapiro[4.4]nonan-
2-yl]methyl hexadecanoate (11a). Using the general procedure (I),
starting from compound 7 (300 mg, 1.6 mmol) and palmitic acid
(900 mg, 3.51 mmol) compound 11a (857 mg, 80%) was isolated
as a white solid. Mp: 98–99 1C; Rf 0.35 (EtOAc/Hexane, 1 : 6);
(2S,3S)-1,4-bis(benzyloxy)-3-(hexadecanoyloxy)butan-2-yl hexa-
decanoate (10a). Using the general procedure (I), starting from
compound 9 (200 mg, 0.662 mmol) and palmitic acid (373.4 mg,
1.46 mmol) compound 10a (437.5 mg, 85%) was isolated as a
white solid. Mp: 95–97 1C; Rf 0.45 (EtOAc/Hexane, 1 : 9);
1
[a]2D0 = ꢀ17.3 (c 0.1, CH2Cl2); H NMR (400 MHz, CDCl3):
1
[a]2D0 = ꢀ9.2 (c 0.1, CH2Cl2); H NMR (400 MHz, CDCl3):
dppm 4.20–4.08 (m, 2H), 3.93–3.78 (m, 2H), 3.62–3.59 (m, 2H),
2.35–2.26 (m, 4H), 1.89–1.83 (m, 4H), 1.76–1.56 (m, 8H), 1.18
(br s, 48H), 0.82–0.78 (m, 6H); 13C NMR (100 MHz, CDCl3):
dppm 173.2, 120.4, 76.0, 63.9, 49.8, 37.4, 36.1, 34.2, 32.9, 32.1,
31.0, 29.84, 29.8, 29.6, 29.56, 29.5, 29.4, 29.3, 26.5, 25.7, 25.5,
25.0, 24.9, 23.7, 22.8, 21.0, 14.3; FT-IR (KBr) n 2918, 2849,
1702, 1627, 1463, 1310, 1295, 1088, 940 cmꢀ1; HR-MS m/z (%):
calcd. for C41H76O6Na+ [M + Na]+: 687.5534, found:
687.5535.
dppm 7.27–7.19 (m, 10H), 5.30 (m, 2H), 4.38 (dd, J = 12 Hz,
J = 12 Hz, 4H), 3.47 (m, 4H), 2.23–2.20 (m, 4H), 1.52–1.50
(m, 4H), 1.18 (m, 48H), 0.81 (t, J = 5.8 Hz, 6H); 13C NMR
(100 MHz, CDCl3): dppm 173.2, 137.8, 128.5, 127.9, 73.3, 70.7,
62.4, 35.9, 34.2, 33.5, 32.7, 32.1, 31.0, 29.8, 29.6, 29.5, 29.4,
29.2, 26.4, 25.7, 25.6, 25.5, 24.9, 24.9, 22.8, 14.2; FT-IR (KBr)
n 2926, 2854, 1711, 1639, 1458, 1263, 1160, 1108, 1026, 790,
713, 697 cmꢀ1; HR-MS m/z (%): calcd. for C50H82O6Na+
[M + Na]+: 801.6004, found: 801.6005.
(2S,3S)-4-hexadecanoloxy-2,3-dihydroxybutyl hexadecanoate
(2a). Using the general procedure (III), starting from compound
11a (500 mg, 0.7523 mmol) compound 2a (370 mg, 82%) was
isolated as a white solid. Mp: 95–96 1C; Rf 0.36 (EtOAc/Hexane,
1 : 7); [a]2D0 = ꢀ10.0 (c 0.1, CH2Cl2); 1H NMR (400 MHz,
CDCl3): dppm 4.24–4.13 (m, 4H), 3.80 (m, 2H), 2.68 (br s, 2H),
2.36–2.30 (m, 4H), 1.60–1.58 (m, 4H), 1.23 (br s, 48H),
0.87–0.84 (m, 6H); 13C NMR (100 MHz, CDCl3): dppm
174.4, 69.8, 65.5, 34.5, 34.4, 32.1, 29.9, 29.9, 29.7, 29.6, 29.5,
29.3, 25.1, 22.9, 14.3; FT-IR (KBr) n 3435, 2955, 2917, 2849,
1736, 1638, 1463, 1383, 1178, 1094 cmꢀ1; HR-MS m/z (%): calcd.
for C36H70O6Na+ [M + Na]+: 621.5065, found: 621.5065.
(2S,3S)-3-(hexadecanoyloxy)-1,4-dihydroxybutan-2-yl hexa-
decanoate (1a). Using the general procedure (II) starting from
compound 10a (250 mg, 0.321 mmol) and 10% Pd–C (3.81 mg,
0.0321 mmol), compound 1a (171 mg, 90%) was isolated as a
white solid. Mp: 97–98 1C; Rf 0.36 (EtOAc/Hexane, 1:7);
1
[a]2D0 = ꢀ8.0 (c 0.1, CH2Cl2); H NMR (400 MHz, CDCl3):
dppm 5.29 (m, 2H), 3.77–3.70 (m, 4H), 2.12–2.11 (m, 2H),
1.92–1.86 (m, 2H), 1.71–1.61 (m, 4H), 1.25 (br s, 48H), 0.88
(m, 6H); 13C NMR (100 MHz, CDCl3): dppm 173.4, 73.3, 62.4,
35.9, 34.2, 33.5, 32.7, 32.0, 30.9, 29.8, 29.6, 29.5, 29.4, 29.2,
26.4, 25.7, 25.6, 25.5, 24.9, 24.8, 22.8, 14.2; FT-IR (KBr) n 3448,
3301, 2919, 2850, 1733, 1638, 1549, 1463, 1384, 1248, 1121 cmꢀ1
;
HR-MS m/z (%): calcd. for C36H70O6Na+ [M + Na]+:
[(2S,3S)-3-[(octanoyloxy)methyl]-1,4-dioxapiro[4.4]nonan-2-yl]-
methyl octanoate (11b). Using the general procedure (I), starting
from compound 7 (300 mg, 1.6 mmol) and octanoic acid
(506.18 mg, 3.51 mmol) compound 11b (600 mg, 85%) was
isolated as colourless oil. Rf 0.32 (EtOAc/Hexane, 1 : 7);
621.5065, found: 621.5064.
(2S,3S)-1,4-bis(benzyloxy)-3-(octanoloxy)butan-2-yl octanoate
(10b). Using the general procedure (I), starting from compound 9
(200 mg, 0.662 mmol) and octanoic acid (211 mg, 1.46 mmol)
compound 10b (313 mg, 85%) was isolated as colorless syrup.
Rf 0.37 (EtOAc/Hexane, 1 : 9); [a]2D0 = ꢀ6.7 (c 0.1, CH2Cl2);
1H NMR (400 MHz, CDCl3): dppm 7.25–7.18 (m, 10H), 5.29
(m, 2H), 4.38 (dd, J = 12, J = 12 Hz, 4H), 3.47 (m, 4H),
2.28–2.19 (m, 4H), 1.57–1.49 (m, 4H), 1.20 (m, 16H), 0.80
(m, 6H); 13C NMR (100 MHz, CDCl3): dppm 173.2, 137.8,
128.5, 127.9, 73.3, 70.7, 68.3, 34.4, 34.2, 31.8, 29.2, 29.15, 29.1,
29.0, 25.1, 24.8, 22.7, 14.2; FT-IR (KBr) n 2926, 2855, 1717, 1457,
1263, 1160, 1107, 1026, 804, 746, 713 cmꢀ1; HR-MS m/z (%):
calcd. for C34H50O6Na+ [M + Na]+: 577.3505, found: 577.3501.
1
[a]2D0 = ꢀ7.3 (c 0.1, CH2Cl2); H NMR (400 MHz, CDCl3):
dppm 4.20–4.11 (m, 4H), 3.94–3.93 (m, 2H), 2.30–2.25 (m, 4H),
1.77–1.76 (m, 4H), 1.61–1.55 (m, 8H), 1.22 (br s, 16H),
0.82–0.79 (m, 6H); 13C NMR (100 MHz, CDCl3): dppm 174.1,
120.4, 75.9, 63.9, 49.9, 37.4, 35.9, 34.2, 32.7, 31.8, 31.0, 29.8,
29.2, 29.0, 26.4, 25.6, 25.4, 24.9, 32.6, 22.7, 20.9, 14.1; FT-IR
(KBr) n 2918, 2849, 1703, 1627, 1463, 1310, 1295, 1088, 941 cmꢀ1
;
HR-MS m/z (%): calcd. for C25H44O6Na+ [M + Na]+:
463.3030, found: 463.3031.
(2S,3S)-2,3-dihydroxy-4-(octanoloxy)butyloctanoate (2b). Using
the general procedure (III), starting from compound 11b (500 mg,
1.135 mmol) compound 2a (349 mg, 82%) was isolated as a
colourless oil. Rf 0.35 (EtOAc/Hexane, 1 : 4); [a]2D0 = ꢀ9.2 (c 0.1,
CH2Cl2); 1H NMR (400 MHz, CDCl3): dppm 4.21–4.11 (m, 4H),
3.85–3.78 (m, 2H), 2.93 (br s, 2H), 2.36–2.24 (m, 4H), 1.60–1.57
(m, 4H), 1.25 (br s, 16H), 0.86–0.82 (m, 6H); 13C NMR
(100 MHz, CDCl3): dppm 174.2, 69.7, 65.4, 34.4, 34.3, 31.8,
29.2, 29.1, 25.0, 22.8, 14.2; FT-IR (KBr) n 3449, 3300, 2928,
(2S,3S)-1,4-dihydroxy-3-(octanoloxy)butan-2-yl octanoate (1b).
Using the general procedure (II), starting from compound 10b
(250 mg, 0.451 mmol) and 10% Pd–C (5.34 mg, 0.0451 mmol),
compound 1b (152 mg, 90%) was isolated as a colourless oil.
Rf 0.30 (EtOAc/Hexane, 1 : 4); [a]2D0 = ꢀ11.0 (c 0.1, CH2Cl2);
1H NMR (400 MHz, CDCl3): dppm 5.36–5.32 (m, 1H),
5.20–5.16 (m, 1H), 3.70–3.56 (m, 2H), 3.51–3.42 (m, 2H),
c
This journal is The Royal Society of Chemistry 2012
Mol. BioSyst., 2012, 8, 1275–1285 1281