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Helvetica Chimica Acta ± Vol. 81 (1998)
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1391, 1255, 1163, 1042. 1H-NMR (CDCl3) ): 7.88 (s, H C(6)); 5.03 (s, CH2(9)); 4.99 (s,CH2(8)); 2.44 (s, Me(7));
2.28 (t, J 7.8, CH2(15)); 1.27 (m, CH2(16), CH2(17), CH2(18)); 0.87 (t, J 6.9, Me(19)). 13C-NMR (CDCl3/
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CD3OD) ): 173.6 (C(14)); 151.6 (C(3)); 148.0 (C(2)); 139.2 (C(6)); 130.8 (C(4)); 126.2 (C(5)); 61.2 (C(9));
59.6 (C(8)); 40.0 (C(15)); 31.0 (C(16)); 24.4 (C(17)); 22.0 (C(18)); 18.0 (C(7)); 13.6 (C(19)). EI-MS: 267 (3,
M ), 151(60), 123(28), 106(37), 94(22), 71(41), 60(27), 43(100). HR-MS: 267.1476 (C14H21NO4 ; calc.
267.1471).
[5-Hydroxy-4-(hydroxymethyl)-6-methylpyridin-3-yl]methyl Decanoate (5c). As described for 5b, but using
ethyl decanoate (0.7 ml, 3 mol-equiv.) as acylating agent and stirring the suspension for 48 h: 272 mg (64%) of
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5c. M.p. 79 ± 808. IR (KBr): 3430, 3166, 2924, 2852, 2717, 1733, 1384, 1255, 1163, 1048. 1H-NMR (CDCl3) ): 7.88
(s, H C(6)); 5.03 (s, CH2(9)); 4.99 (s, CH2(8)); 2.44 (s, Me(7)); 2.28 (t, J 7.8, CH2(15)); 1.25 (m, CH2(16) ±
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CH2(22)); 0.87 (t, J 6.9, Me(23)). 13C-NMR (CDCl3 :CD3OD) ): 173.4 (C(14)); 151.5 (C(3)); 147.6 (C(2));
138.7 (C(6)); 131.2 (C(4)); 126.4 (C(5)); 61.0 (C(9)); 59.0 (C(8)); 33.7 (C(15)); 31.4 (C(16)); 28.9 (C(17));
28.8 (C(18)); 28.6 (C(19)); 24.5 (C(20)); 24.4 (C(21)); 22.2 (C(22)); 17.5 (C(7)); 13.4 (C(23)). EI-MS: 323
(1, M ), 151(77), 123(50), 106(43), 94(21), 71(30), 55(43), 43(100). HR-MS: 323.2097 (C18H29NO4 ; calc.
323.2097).
[5-Hydroxy-4-(hydroxymethyl)-6-methylpyridin-3-yl]methyl Tetradecanoate (5d). As described for 5b, but
using ethyl tetradecanoate (0.9 ml, 3 mol-equiv.) as acylating agent and stirring the suspension for 72 h: 283 mg
(57%) of 5d. M.p. 93 ± 948. IR (KBr): 3435, 3183, 2924, 2859, 2695, 1747, 1427, 1241, 1170, 1042. 1H-NMR
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(CDCl3) ): 7.88 (s, H C(6)); 5.03 (s, CH2(9)); 4.99 (s, CH2(8)); 2.44 (s, Me(7)); 2.28 (t, J 7.8, CH2(15)); 1.25
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(m, CH2(16) ± CH2(26)); 0.87 (t, J 6.9, Me(27)). 13C-NMR (CDCl3 :CD3OD) ): 173.6 (C(14)); 151.6 (C(3));
148.0 (C(2)); 139.2 (C(6)); 130.9 (C(4)); 126.3 (C(5)); 61.2 (C(9)); 59.6 (C(8)); 33.9 (C(15)); 31.7 (C(16)); 29.4,
29.2, 29.1, 29.0, 28.9 (C(17) to C(24)); 24.7 (C(22)); 22.5 (C(23)); 17.9 (C(7)); 13.8 (C(27)). EI-MS: 379 (1,
M ), 151(100), 123(55), 106(29), 94(13), 71(15), 57(41), 43(92). HR-MS: 379.2725 (C22H37NO4 ; calc.
379.2723).
4,5-Bis(acetoxymethyl)-2-methylpyridin-3-yl Acetate (6). A mixture of pyridoxine hydrochloride (450 mg,
2.2 mol-equiv.) and excess Ac2O in 1.5 ml of dry pyridine was kept overnight at r.t. The mixture was poured into
ice-water to remove the excess reagents. The oily phase was separated and AcOEt (30 ml) was added. The
resulting soln. was washed with aq. 1n NaOH soln. (5 Â 20 ml) and H2O (2 Â 20 ml), dried (Na2SO4), and
evaporated in vacuo: 6 (370 mg, 57%). Viscous oil [24]. IR (film): 2970, 2942, 1763, 1602, 1370, 1225, 1041. 1H-
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NMR (CDCl3) ): 8.37 (s, H C(6)); 5.19 (s, CH2(8)); 5.07 (s, CH2(9)); 2.34 (s, Me(7)); 2.31 (s, Me(11)); 2.01
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(s, Me(15)); 1.96 (s, Me(13)). 13C-NMR (CDCl3) ): 170.1 (C(12)); 170.0 (C(14)); 168.3 (C(10)); 153.0 (C(3));
147.7 (C(6)); 144.5 (C(2)); 135.4 (C(4)); 129.3 (C(5)); 61.0 (C(9)); 56.7 (C(8)); 20.6 (C(13)); 20.3 (C(15),
C(11)); 19.4 (C(7)). EI-MS: 295 (2, M ), 253(35), 235(26), 193(66), 151(100), 123(62), 106(51), 94(19),
43(79).
4-(Acetoxymethyl)-5-(hydroxymethyl)-2-methylpyridin-3-yl Acetate (7). To a soln. of 6 (200 mg, 0.68 mmol)
in abs. EtOH (10 ml), 800 mg of CAL were added. The suspension was shaken (200 rpm) at 308 and the progress
of reaction monitored by TLC (AcOEt). After 24 h, the enzyme was filtered off, the solvent evaporated, and the
crude residue purified by chromatography (silica gel; AcOEt): 136 mg (80%) of 7. M.p. 88 ± 898 ([22]: 90 ± 928).
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IR (KBr): 3450, 3197, 2919, 1773, 1736, 1240, 1205, 1035. 1H-NMR ((D6)DMSO) ): 8.37 (s, H C(6)); 5.08
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(s, CH2(8)); 4.62 (s, CH2(9)); 2.35 (s, Me(7)); 2.29 (s, Me(11)); 1.97 (s, Me(13)). 13C-NMR ((D6)DMSO) ):
170.0 (C(12)); 168.8 (C(10)); 150.8 (C(3)); 146.0 (C(6)); 144.3 (C(2)); 135.3 (C(4)); 134.6 (C(5)); 58.5 (C(9));
56.8 (C(8)); 20.4 (C(13)); 19.2 (C(11)); 17.4 (C(7)). EI-MS: 253 (2, M ), 211(4), 193(30), 151(54), 123(15),
94(46), 43(100).
3-Hydroxy-6-methylpyridine-3,4-dimethyl Diacetate (8). This compound was prepared according to [25] to
give 4,5-bis(acetoxymethyl)-3-hydroxy-2-methylpyridine hydrochloride (1.69 g). The hydrochloride was
dissolved in H2O, and aq. NH3 was added until precipitation of a white solid (pH 6.05). The white solid
was filtered off and washed with H2O to provide 8 (1.3 g, 70%). M.p. 97 ± 988 ([26]: 99 ± 1008). IR (KBr):
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3458, 2945, 2375, 1755, 1740, 1384, 1234, 1042, 1027. 1H-NMR ((D6)DMSO) ): 7.99 (s, H C(6)); 5.13
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(s, CH2(8)); 5.10 (s, CH2(9)); 2.40 (s, Me(7)); 2.01 (s, Me(13), Me(15)). 13C-NMR ((D6)DMSO) ): 170.4
(C(12)); 170.2 (C(14)); 150.0 (C(3)); 148.3 (C(2)); 141.0 (C(6)); 129.3 (C(4)); 128.8 (C(5)); 61.5 (C(9)); 57.1
(C(8)); 20.7 (C(15), C(13)); 20.0 (C(7)). EI-MS: 253 (18, M ), 193 (44, [M AcOH] ), 151(76), 123(61),
106(62), 94(32), 43(100).
[3-Hydroxy-5-(hydroxymethyl)-2-methylpyridin-4-yl]methyl Acetate (9). This compound was prepared as
described for 7, but using 200 mg (0.79 mmol) of 8 as substrate: 119 mg (69%) of 9. M.p. 104 ± 1058 ([23]: 155 ±
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1578). IR (KBr): 3309, 2930, 2517, 2097, 1749, 1526, 1377, 1241, 1035. 1H-NMR ((D6)DMSO) ): 7.97 (s, H C(6));