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(55 mg, 0.46 mmol) was stirred at 120 ꢀC for 3 h, then cooled to 3.65 (m, 2H, OCH2), 3.43 (s, 3H, OMe), 2.83 (dd, 1H, J1eq,1ax
¼
room temperature and directly eluted from a column of silica 10.2 Hz, H-1eq), 2.88–2.78 and 2.59–2.48 (2m, 2H, NCH2), 2.45
gel with 6 : 1 toluene–Et2O (containing 0.5% of triethylamine) to (s, 3H, NAc), 2.20–2.12 (m, 1H, H-5), 1.88 (dd, 1H, H-1ax), 1.81,
give 9 (250 mg, 82%) as a colorless oil; [a]D ¼ ꢁ1.5 (c 1.2, CHCl3). 1.75, 1.72, and 1.66 (4s, 12H, 4Ac), 1.57–1.46 (m, 2H, NCH2CH2).
1H NMR (C6D6): d 7.42–7.37 (m, 2H, Ar), 7.35–7.26 (m, 8H, Ar), MS (ESI): m/z calcd for C28H37N2O13 [M + H]+ 609.23, found
7.21–7.06 (m, 12H, Ar), 6.82–6.76 (m, 2H, Ar), 5.09 and 4.91 (2d, 609.25; m/z calcd for C28H36N2NaO13 [M + Na]+ 631.21, found
2H, J ¼ 11.1 Hz, PhCH2), 5.07 and 4.62 (2d, 2H, J ¼ 11.3 Hz, 631.25.
PhCH2), 4.60 and 4.55 (2d, 2H, J ¼ 11.1 Hz, PhCH2), 4.32 (s, 2H,
PhCH2), 4.05 (t, 2H, J ¼ 6.5 Hz, OCH2), 3.77 (ddd, 1H, J1eq,2
4.8, J2,3 ¼ 8.9, J1ax,2 ¼ 11.0 Hz, H-2), 3.76 (dd, 1H, J3,4 ¼ 8.9, J4,5
¼
¼
2,3,4,6-Tetra-O-acetyl-1,5-dideoxy-1,5-imino-N-(3-
phthalimidoxynonyl)-D-glucitol (11a), N-{3-[N-acetyl-N-(2-
methoxycarbonyl-benzoyl)]-aminoxynonyl}-2,3,4,6-tetra-O-
acetyl-1,5-dideoxy-1,5-imino-D-glucitol (11b) and 2,3,4,6-tetra-
O-acetyl-1,5-dideoxy-1,5-imino-N-{3-[N-(2-methoxycarbonyl-
benzoyl)]-aminoxynonyl}-D-glucitol (11c)
9.0 Hz, H-4), 3.74 (dd, 1H, J5,6a ¼ 3.2, J6a,6b ¼ 10.2 Hz, H-6a), 3.66
(dd, 1H, H-3), 3.65 (dd, 1H, J5,6b ¼ 2.0 Hz, H-6b), 3.16 (dd, 1H,
J1eq,1ax ¼ 11.0 Hz, H-1eq), 2.88–2.78 (m, 1H, 1H of NCH2), 2.60–
2.51 (m, 1H, 1H of NCH2), 2.47 (ddd, 1H, H-5), 2.25 (dd, 1H, H-
1ax), 1.98–1.59 (m, 2H, CH2), 1.49–1.35 (m, 4H, 2CH2), 1.32–1.15
(m, 8H, 4CH2). 13C NMR (C6D6): d 163.4 (C), 140.0 (C), 139.8 (C),
139.6 (C), 138.9 (C), 133.8 (CH), 129.6 (C), 128.8–127.3 (CH),
123.0 (CH), 87.9 (CH), 79.6 (CH), 79.4 (CH), 78.5 (CH2), 75.4
(CH2), 75.2 (CH2), 73.3 (CH2), 72.7 (CH2), 68.0 (CH2), 65.4 (CH),
55.0 (CH2), 53.0 (CH2), 30.0 (CH2), 29.9 (CH2), 29.6 (CH2), 28.6
(CH2), 27.8 (CH2), 26.1 (CH2), 25.6 (CH2). HRMS (ESI/Q-TOF) m/z
calcd for C51H59N2O7 [M + H]+ 811.4322, found 811.4324.
To a stirred, cooled (ꢁ60 ꢀC) solution of 9 (140 mg, 0.17 mmol)
in anhydrous CH2Cl2 (3.3 mL) was slowly added a 1 M solution
of BCl3 in CH2Cl2 (1.7 mL, 1.7 mmol). The solution as allowed to
warm to ꢁ10 ꢀC over 1 h, then MeOH (0.8 mL) was added
dropwise and the solution was allowed to warm to 0 ꢀC over
30 min. Et3N (0.8 mL) was added dropwise and the solution was
concentrated. A suspension of the residue in pyridine (1 mL)
and acetic anhydride (2 mL) was stirred at room temperature for
24 h, then concentrated, diluted in H2O (50 mL), and extracted
with AcOEt (3 ꢃ 50 mL). The combined organic layers were
dried (Na2SO4) and concentrated. The residue was eluted from
a column of silica gel with 2 : 1 cyclohexane–AcOEt (containing
1% of Et3N) to give a ca. 4 : 2 : 1 mixture of 11a, 11b, and 11c
(93 mg, 85%) as a white foam that was used for the next step
without further purication. 1H NMR (C6D6): d 7.88–7.83 (m,
1 arom. H of 11b), 7.81–7.77 (m, 1 arom. H of 11c), 7.68–7.63 (m,
1 arom. H of 11c), 7.37–7.35 (m, 1 arom. H of 11c), 7.35–7.29 (m,
2 arom. H of 11a), 7.08–7.02 (m, 1 arom. H of 11b), 7.01–6.94 (m,
2 arom. H of 11b), 6.92–6.86 (m, 1 arom. H of 11c), 6.84–6.77 (m,
2 arom. H of 11a), 5.42–5.35 (m, 1H, H-3), 5.35–5.29 (m, 1H,
H-4), 5.27–5.18 (m, 1H, H-2), 4.26–4.09 (m, 2H, H-6a, H-6b,
+OCH2 of 11c), 4.06 (t, J ¼ 6.5 Hz, OCH2 of 11a), 3.88–3.78 (m,
OCH2 of 11b), 3.58 (s, OMe of 11c), 3.38 (s, OMe of 11b), 3.16–
3.08 (m, 1H, H-1eq), 2.59–2.42 (m, 1H, 1H of NCH2), 2.46 (s, NAc
of 11b), 2.40–2.26 (m, 2H, 1H of NCH2, H-5), 2.10–1.99 (m, 1H,
H-1ax), 1.80–1.72 (4s, 9H, 3Ac), 1.66 (s, 3H, Ac), 1.68–1.58 and
1.48–0.95 (2m, 14H, 7CH2).
2,3,4,6-Tetra-O-acetyl-1,5-dideoxy-1,5-imino-N-(3-
phthalimidoxypropyl)-D-glucitol (10a) and N-{3-[N-acetyl-N-(2-
methoxycarbonyl-benzoyl)]-aminoxypropyl}-2,3,4,6-tetra-O-
acetyl-1,5-dideoxy-1,5-imino-D-glucitol (10b)
To a stirred, cooled (ꢁ60 ꢀC) solution of 8 (148 mg, 0.20 mmol)
in anhydrous CH2Cl2 (4 mL) was slowly added a 1 M solution of
BCl3 in CH2Cl2 (2.1 mL, 2.1 mmol). The solution was allowed to
warm to ꢁ10 ꢀC over 1 h, then MeOH (0.8 mL) was added
dropwise and the solution was allowed to warm to 0 ꢀC over
30 min. Et3N (0.8 mL) was added dropwise and the solution was
concentrated. A suspension of the residue in pyridine (1 mL)
and acetic anhydride (2 mL) was stirred at room temperature for
24 h, then concentrated, diluted in H2O (50 mL), and extracted
with AcOEt (3 ꢃ 50 mL). The combined organic layers were
dried (Na2SO4) and concentrated. The residue was eluted from
a column of silica gel with 1 : 1 AcOEt–cyclohexane (containing
1% of Et3N) to give a ca. 2 : 1 mixture of 10a and 10b (97 mg,
85%) as a white foam that was used for the next step without
further purication.
11a. MS (ESI): m/z calcd for C31H43N2O11 [M + H]+ 619.29,
found 619.25; m/z calcd for C31H42N2NaO11 [M + Na]+ 641.27,
found 641.25.
1
10a. H NMR (C6D6): d 7.32–7.25 (m, 2H, Ar), 6.84–6.76 (m,
2H, Ar), 5.34 (dd, 1H, J2,3 ¼ J3,4 ¼ 8.9 Hz, H-3), 5.29 (dd, 1H, J4,5
¼ 8.9 Hz, H-4), 5.19 (ddd, 1H, J1eq,2 ¼ 4.9, J1ax,2 ¼ 10.2 Hz, H-2),
4.31 (dd, 1H, J5,6a ¼ 3.6, J6a,6b ¼ 12.9 Hz, H-6a), 4.19 (dd, 1H, J5,6b
11b. MS (ESI): m/z calcd for C34H49N2O13 [M + H]+ 693.32,
found 693.30; m/z calcd for C34H48N2NaO13 [M + Na]+ 715.30,
found 715.30.
¼ 2.0 Hz, H-6b), 4.02–3.92 (m, 2H, OCH2), 3.06 (dd, 1H, J1eq,1ax
¼
11c. MS (ESI): m/z calcd for C32H47N2O12 [M + H]+ 651.31,
found 651.35.
11.5 Hz, H-1eq), 2.87–2.78 and 2.58–2.48 (2m, 2H, NCH2), 2.29
(ddd, 1H, H-5), 2.02 (dd, 1H, H-1ax), 1.83, 1.78, 1.74, and 1.68
(4s, 12H, 4Ac), 1.57–1.46 (m, 2H, NCH2CH2). MS (ESI): m/z calcd
for C25H31N2O11 [M + H]+ 535.19, found 535.20; m/z calcd for
N-(3-Aminooxy-propyl)-1,5-dideoxy-1,5-imino-D-glucitol (12)
A solution of 10a and 10b (2 : 1 mixture, 92 mg, 0.16 mmol) in
C
25H30N2NaO11 [M + Na]+ 557.17, found 557.20.
1
10b. H NMR (C6D6): d 7.90–7.85 (m, 1H, Ar), 7.13–7.08 (m, a 2 M solution of NH3 in methanol (3.4 mL) was kept at room
2H, Ar), 7.06–7.00 (m, 1H, Ar), 5.25–5.19 (m, 2H, H-3, H-4), 5.08 temperature under argon atmosphere for 14 h and then
(ddd, 1H, J1eq,2 ¼ 5.3, J1ax,2 ¼ J2,3 ¼ 10.2 Hz, H-2), 4.15 (dd, 1H, concentrated. The residue was eluted from a column of silica gel
J5,6a ¼ 3.7, J6a,6b ¼ 12.9 Hz, H-6a), 4.08–3.91 (m, 1H, H-6b), 3.74– with 7 : 3 CH2Cl2–EtOH and then EtOH to give 12 (35 mg, 93%)
2214 | RSC Adv., 2016, 6, 2210–2216
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