ORDER
REPRINTS
Apio Nucleosides
721
7
.25–8.10 (m, 15 H, 3 Â Bz), 6.42 (s, 1 H, H-1), 5.99 (s, 1 H, H-2), 5.16 (d, 1 H,
J = 12.5 Hz, H -3’), 4.99 (d, 1 H, J = 12.5 Hz, H -3’), 4.68 (d, 1 H, J = 10.6 Hz, H -4),
a
b
a
4
1
.55 (d, 1 H, J = 10.6 Hz, H -4), 2.14 (s, 3 H, OAc); IR (KBr): 3066, 1728, 1267,
b
À1
+
+
109, 710 cm ; FAB-MS m/z: 527 [M + Na] , 445 [M- OAc] .
2,3,3’ -Tri-O-benzoyl-b-D-apiofuranosyl cyanide (10). To a stirred solution of 9
(
789 mg, 1.56 mmol) in anhydrous CH Cl (10 mL) were added TMSCN (0.83 mL,
2
2
6.22 mmol) and SnCl (1 M solution in CH Cl , 0.31 mL) and the reaction mixture was
refluxed for 3 h, cooled to room temperature and patitioned between CH Cl /H O. The
4 2 2
2
2
2
organic layer was washed with brine, dried (MgSO ), filtrated and evaporated. The
4
residue was purified by silica gel column chromatography (Hex/EtOAc = 4/1) to give
1
1
0 (512 mg, 69%) as an oil. H NMR (300 MHz, CDCl ): d 7.28–8.14 (m, 15 H,
3
3
 Bz), 6.12 (d, 1 H, J = 4.2 Hz, H-1), 5.08 (d, 1 H, J = 12.3 Hz, H -3’), 4.93 (d, 1
a
H, J = 12.3 Hz, H -3’), 4.92 (d, 1 H, J = 4.1 Hz, H-2), 4.69 (d, 1 H, J = 10.7 Hz, H -
4), 4.46 (d, 1 H, J = 10.7 Hz, H -4); IR (KBr): 3067, 1729, 1280, 1104, 710 cm
FAB-MS m/z: 494 [M + Na] , 445 [M- CN] .
b
a
À1
;
b
+
+
Ethyl 2-(2’ ,3’ ,3’ ’ -Tri-O-benzoyl–apio-b-D-furanosyl)thiazoline-4-carboxylate
11). To a stirred solution of 10 (512 mg, 1.09 mmol) in anhydrous MeOH (15 mL)
(
was added L-cysteine ethyl ester hydrochloride (302 mg, 1.63 mmol) followed by TEA
0.23 mL, 1.66 mmol) at room temperature. The reaction mixture was stirred for 2 h and
evaporated. The residue was dissolved in CH Cl and the organic layer was washed
(
2
2
with water, sat. NaHCO solution and brine. The organic layer was dried (MgSO ),
3
4
filtrated and evaporated. The residue was purified by silica gel column chromatography
1
(
Hex/EtOAc = 3/1) to give 11 (459 mg, 71%) as an oil. H NMR (300 MHz, CDCl ): d
3
7
.24–8.06 (m, 15 H, 3 Â Bz), 6.14 (d, 1 H, J = 5.0 Hz, H-1’), 5.15(m, 1 H, H-4), 5.08
(
dd, 1 H, J = 1.5, 5.0 Hz, H-2’), 5.07 (d, 1 H, J = 12.3 Hz, H -3’’), 4.81 (d, 1 H,
a
J = 12.3 Hz, H -3’’), 4.77 (d, 1 H, J = 10.6 Hz, H -4’), 4.43 (d, 1 H, J = 10.6 Hz,
b
a
H -4’), 4.01–4.17 (m, 2 H, OCH CH ), 3.50–3.64 (m, 2 H, H-5), 1.13 (t, 3 H,
b
2
3
À1
J = 7.1 Hz, OCH CH ); IR (KBr): 2984, 1720, 1273, 1107, 711 cm ; FAB-MS m/z:
2
3
+
+
6
2
26 [M + Na] , 604 [M + H] ; Anal calcd for C H NO S: C, 63.67; H, 4.84; N,
32 29 9
.32; S,5.31. Found: C, 63.42; H, 5.02; N, 2.44; S, 5.53.
Ethyl 2-(2’ ,3’ ,3’ ’ -Tri-O-benzoyl-apio-b-D-furanosyl)thiazole-4-carboxylate
12). To a stirred solution of 11 (459 mg, 0.76 mmol) in anhydrous CH Cl
20 mL) was added 1,8-diazabicyclo[5.4.0]-undec-7-ene (0.23 mL, 1.54 mmol). The
(
(
2
2
solution was cooled to 0°C and bromotrichloromethane (0.09 mL, 0.91 mmol) was
added dropwise. The reaction mixture was stirred at 0°C for 16 h and evaporated. The
residue was dissolved in EtOAc and washed with sat. aqueous NH Cl solution (Â3).
4
The organic layer was dried (MgSO ), filtrated and evaporated. The residue was
4
purified by silica gel column chromatography (Hex/EtOAc = 2/1) to give 12 (340 mg,
1
7
7
4%) as a solid. mp:129 ꢀ 131°C; H NMR (300 MHz, CDCl ): d 8.20 (s, 1 H, H-5),
3
.25–8.09 (m, 15 H, 3 Â Bz), 6.01 (d, 1 H, J = 5.0 Hz, H-1’), 5.60 (d, 1 H, J = 5.0 Hz,
H-2’), 5.06 (d, 1 H, J = 12.1Hz, H -3’’), 4.89 (d, 1 H, J = 10.7 Hz, H -4’), 4.74 (d, 1 H,
a
a
J = 12.1 Hz, H -3’’), 4.50 (d, 1 H, J = 10.8 Hz, H -4’), 4.32 (q, 2 H, J = 7.2 Hz,
b
b
OCH CH ), 1.31 (t, 3 H, J = 7.1 Hz, OCH CH ); IR (KBr): 2921, 1727, 1601, 1267,
2
3
2
3