Helvetica Chimica Acta ± Vol. 83 (2000)
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5-Amino-3,4,6-tri-O-benzyl-5-deoxy-d-mannonolactam (58). As described for 36, with 57 (600 mg,
0.558 mmol): 58 (424 mg, 85%). Colourless oil. Rf (AcOEt/hexane 2 :1) 0.51. IR (CHCl3): 3453w (br.),
3394m, 3089w, 3066w, 2868m, 1496s, 1454w, 1361m, 1310m, 1262m, 1093m, 1073s, 1028m, 909w. 1H-NMR
(CDCl3): 3.45 (t, J 9.0, H C(6)); 3.49 (dd, J 4.1, 3.1, H C(4)); 3.51 (dd, J 9.3, 4.1, H C(6)); 3.61 ± 3.66
(m, H C(5)); 4.11 (t, J 3.1, irrad. at 4.44 ! d, J ꢀ 3.0, H C(3)); 4.31 (d, J 11.5, PhCH); 4.44 (d, J 11.5,
PhCH); 4.44 (d, J 3.1, irrad. at 4.11 ! s, H C(2)); 4.45 (br. s, exchange with CD3OD, OH); 4.47 (s, PhCH2);
4.63 (d, J 12.1, PhCH); 4.83 (d, J 12.1, PhCH); 6.19 (s, exchange with CD3OD, NH); 7.17 ± 7.20 (m,
2 arom. H); 7.21 ± 7.42 (m, 13 arom. H). 13C-NMR (CDCl3): 55.15 (d, C(5)); 69.06 (d, C(2)); 70.58 (t, C(6));
71.63, 73.32, 73.80 (3t, 3 PhCH2); 75.63, 77.07 (2d, C(3), C(4)); 127.87 ± 128.58 (several d); 137.06, 137.32, 138.06
(3s); 171.83 (s, CO). FAB-MS: 448 (100, [M 1] ).
2-O-Acetyl-5-amino-3,4,6-tri-O-benzyl-5-deoxy-d-mannonolactam (59). As described for 37, with 58
(872 mg, 1.86 mmol): 59 (950 mg, 98%) which was used for the next reaction without further purification. Rf
(AcOEt/hexane 2 :1) 0.53. IR (CHCl3): 3393m, 3089w, 3067m, 3008m, 2920m, 2867m, 1749s, 1687s, 1496w,
1454m, 1371m, 1318w, 1094s, 1028m, 909m. 1H-NMR (CDCl3): 2.21 (s, AcO); 3.44 (t, J 9.0, H C(6)); 3.51
(dd, J 9.3, 4.7, H C(6)); 3.57 (br. t, J 4.1, H C(4)); 3.66 ± 3.71 (m, H C(5)); 4.04 (dd, J 4.1, 3.1, irrad. at
5.65 ! d, J 4.1, H C(3)); 4.41 (d, J 11.8, PhCH); 4.44 (d, J 11.5, PhCH); 4.49 (d, J 11.8, PhCH); 4.54
(d, J 11.8, 2 PhCH); 4.70 (d, J 12.1, PhCH); 5.65 (d, J 3.1, H C(2)); 6.01 (br. s, exchange with CD3OD,
NH); 7.19 ± 7.39 (m, 15 arom. H). 13C-NMR (CDCl3): 20.95 (q, Me); 55.46 (d, C(5)); 69.70 (d, C(2)); 70.99
(t, C(6)); 72.16, 73.10, 73.44 (3t, 3 PhCH2); 77.69, 80.55 (2d, C(3), C(4)); 128.10 ± 129.95 (several d); 137.29,
137.63, 137.70 (3s); 166.98 (s, NCO); 170.29 (s, OCO). FAB-MS: 490 (21, [M 1] ), 281 (76), 147 (100), 91
(83), 73 (89).
2-O-Acetyl-5-amino-3,4,6-tri-O-benzyl-5-deoxy-d-mannonothiolactam (60). As described for 41, the
conversion of 59 (480 mg, 1.073 mmol) with Lawessonꢁs reagent (240 mg, 2.45 mmol) in toluene (5 ml) gave
60 (458 mg, 92%). Yellowish oil. Rf (AcOEt/hexane 1:3) 0.52. IR (CHCl3): 3362m, 3069w, 3067w, 3008m,
2916m, 2868m, 1953w, 1748s, 1599w, 1520s, 1497s, 1454m, 1370m, 1316m, 1096s, 910m. 1H-NMR (300 MHz,
CDCl3): 2.24 (s, AcO); 3.44 (t, J 9.3, H C(6)); 3.52 (dd, J 9.3, 3.7, H C(6)); 3.57 ± 3.64 (m, H C(4),
H
C(5)); 3.99 (dd, J 4.0, 3.1, irrad. at 5.83 ! d, J 4.0, H C(3)); 4.39 (d, J 11.5, PhCH); 4.46 (d, J 11.8,
PhCH); 4.51 (d, J 11.8, PhCH); 4.56 (d, J 11.8, PhCH); 4.58 (d, J 11.8, PhCH); 4.77 (d, J 12.1, PhCH);
5.83 (d, J 3.1, H C(2)); 7.18 ± 7.40 (m, 15 arom. H); 8.20 (br. s, exchange with CD3OD, NH). 13C-NMR
(75 MHz, CDCl3): 21.18 (q, Me); 58.49 (d, C(5)); 69.73 (t, C(6)); 72.58, 73.05, 73.50 (3t, 3 PhCH2); 73.84, 74.41,
76.35 (3d, C(2), C(3), C(4)); 128.17 ± 128.83 (several d); 137.21, 137.32, 137.69 (3s); 170.08 (s, CO); 197.81
(s, CS).
(5R,6R,7S,8R)-8-Acetoxy-6,7-bis(benzyloxy)-5-[(benzyloxy)methyl)]-5,6,7,8-tetrahydro[1,2,4]triazolo[4,3-
a]pyridine (61). As described for 49, the reaction of 60 (100 mg, 0.198 mmol) with Hg(OAc)2 (90 mg,
0.245 mmol) and formylhydrazine (60 mg, 1.0 mmol) in THF (2 ml) gave 61 (73 mg, 76%). Rf (AcOEt) 0.21. IR
(CHCl3): 3008m, 2870w, 1749s, 1498m, 1454m, 1371m, 1112s, 1071s, 1045m, 946w, 910w, 836w. 1H-NMR
(300 MHz, CDCl3): 2.16 (s, AcO); 3.62 (dd, J 9.7, 7.8, CH C(5)); 3.73 (dd, J 10.0, 3.4, CH C(5)); 3.87
(dd, J 7.8, 5.6, H C(6)); 4.08 (dd, J 8.1, 3.7, irrad. at 6.61 ! d, J ꢀ 8.1, H C(7)); 4.25 (ddd, J 8.0, 5.3, 3.4,
H
C(5)); 4.44 (d, J 11.8, PhCH); 4.50 (d, J 12.5, PhCH); 4.54 (d, J 11.5, PhCH); 4.57 (d, J 11.5, PhCH);
4.78 (d, J 11.2, PhCH); 4.84 (d, J 11.5, PhCH); 6.61 (d, J 3.7, H C(8)); 7.21 ± 7.39 (m, 15 arom. H); 8.40
(s, H C(3)). 1H-NMR (75 MHz, CDCl3): 20.91 (q, Me); 58.39 (d, C(5)); 61.11 (d, C(8)); 70.33 (t, CH2 C(5));
73.10, 76.80 (2d, C(6), C(7)); 73.16, 73.64, 74.28, (3t, 3 PhCH2); 128.15 ± 129.30 (several d); 137.16 (s); 137.18
(br. s); 143.08 (d, C(3)); 148.05 (s, C(8a)); 169.81 (s, CO).
(5R,6R,7S,8R)-6,7-Bis(benzyloxy)-5-[(benzyloxy)methyl)]-5,6,7,8-tetrahydro-8-[(methylsulfonyl)oxy][1,2,4]-
triazolo[4,3-a]pyridine (62). As described for 52, with 55 (58 mg, 0.123 mmol) and MsCl (30 ml, 0.386 mmol) in
pyridine (1 ml): 62 (57 mg, 84%). Rf (AcOEt) 0.26. IR (CHCl3): 3150w, 3066m, 3008m, 2928m, 2869m, 1952w,
1
1869w, 1810w, 1734w, 1604w, 1496m, 1412w, 1368s, 1337m, 1261m, 1177s, 1110s, 1028m, 972m, 910m. H-NMR
(300 MHz, CDCl3): 3.29 (s, MeSO2); 3.60 (dd, J 9.7, 8.1, CH C(5)); 3.70 (dd, J 10.0, 3.1, CH C(5)); 3.98
(dd, J 7.8, 5.9, H C(6)); 4.10 (dd, J 8.1, 3.7, irrad. at 6.15 ! d, J 8.1, H C(7)); 4.23 (ddd, J 8.1, 5.9, 2.8,
H
C(5)); 4.43 (d, J 11.5, PhCH); 4.49 (d, J 11.8, PhCH); 4.57 (d, J 11.5, PhCH); 4.64 (d, J 11.5, PhCH);
4.84 (d, J 11.5, PhCH); 4.95 (d, J 11.5, PhCH); 6.15 (d, J 3.4, H C(8)); 7.17 ± 7.41 (m, 15 arom. H); 8.43
(s, H C(3)). 13C-NMR (CDCl3): 39.75 (q, MeSO2); 58.54 (d, C(5)); 69.70 (d, C(8)); 69.99 (t, CH2 C(5)); 72.95
(d); 73.34, 73.66, 74.54 (3t, 3 PhCH2); 76.74 (d); 128.20 ± 128.94 (several d); 136.93, 137.00, 137.06 (3s); 138.02
(d, C(3)); 147.31 (s, C(8a)).
(5R,6R,7S,8S)-8-Amino-5,6,7,8-tetrahydro-5-(hydroxymethyl)[1,2,4]triazolo[4,3-a]pyridine-6,7-diol (2). A
soln. of 56 (60 mg, 0.26 mmol) in MeOH/AcOH 5 :1 (5 ml) was treated with 10% Pd/C (30 mg) and