Darehkordi et al.
1383
Scheme 1.
Methyl 2-((E)-4-oxo-2-((b-d-galactopyranosyl)hydrazono)
thiazolidinone-5-ylidene)acetate (3a)
MeO
O
Yellow powder (recrystallized from EtOH or DMF–H2O);
O
S
OMe
O
S
OMe
H
25
mp 187–189 °C. ½aꢀ –2.7 (c 1.0, DMSO). FT-IR (KBr),
cm–1) ymax: 3180–32D85 (N–H), 2950–3080 (CH, aliphatic),
H
O
S
1
1765, 1662 (C=O), 1615, 1632 (C=N). H NMR (DMSO-
N
N
N
N
O
N
O
HN
N
d6, 500 MHz), ppm) d: 8.90 (1H, NH), 6.75 (1H, HC=C–),
6.58 1H, NH), 4.00–5.12 (m, 4H, OH), 5.08 (1H, H-1), 4.92
(1H, H-2), 4.58 (1H, H-3), 4.11 (1H, H-4), 3.88 (m, 1H, H-
5), 3.96 (1H, H-6), 3.95 (1H, H-6′), 3.73 (3H, –OCH3). 13C
NMR (DMSO-d6, 125.77 MHz), ppm) d: 179.37, 176.69,
165.25 (C=O, NC=O, C=N), 147.88, 117.83 (C=C), 83.18
(C-1), 77.10 (C-5), 74.45 (C-2), 73.95 (C-3), 72.00 (C-4),
61.70 (C-6), 53.7 (–OCH3). Anal. calcd for C12H17N3O8S
(363.35) (%): C 39.67, H 4.72, N 11.56; found: C 39.23, H
4.42, N 11.32.
H
N
R1
H
R1
N
R1
R2
R2
R2
3
2
1
Scheme 2. Synthesis of sugar–thiosemicarbazone derivatives.
OH
H
OH
OH
OH
H
N
H
N
O
H
O
Ethanol/H2O
Reflux
NH2
NH2
OH H2N
HO
NH
+
HO
OH
S
S
OH
Methyl 2-((E)-4-oxo-2-((b-d-glucopyranosyl)hydrazono)
thiazolidinone-5-ylidene)acetate (3c)
1b
Yellow powder (recrystallized from EtOH or DMF–H2O);
25
(30 mL) was added thiosemicarbazide (10 mmol, 0.94 g),
and boiling was continued for an additional 8 h, then the re-
action mixture was cooled to room temperature and allowed
to crystallize, affording a white precipitate as a pyranose
(Scheme 2).9–12
mp 126–128 °C. ½aꢀ +0.4 (c 1.0, DMSO). FT-IR (KBr),
cm–1) ymax: 3210–32D96 (N–H), 2955–3088 (CH, aliphatic),
1
1766, 1666 (C=O), 1614, 1635 (C=N). H NMR (DMSO-
d6, 500 MHz), ppm) d: 9.36 (1H, NH), 7.75 (1H, HC=C–),
6.63 (1H, NH), 3.55–4.90 (m, 4H, OH), 4.90 (1H, H-1),
4.42 (1H, H-2), 4.24 (1H, H-3), 3.75 (1H, H-4), 3.70 (m,
1H,H-5),3.86(1H,H-6),3.86(1H,H-6′),3.62(3H,–OCH3). 13C
NMR (DMSO-d6, 125.77 MHz), ppm) d: 168.53, 166.16,
163.92 (C=O, NC=O, C=N), 142.98 115.38 (C=C), 79.96
(C-1), 76.25 (C-5), 72.27 (C-2), 71.32 (C-3), 70.30 (C-4),
61.25 (C-6), 52.62 (OCH3). Anal. calcd for C12H17N3O8S
(363.35) (%): C 39.67, H 4.72, N 11.56; found: C 39.85,
H 4.82, N 11.42.
A typical procedure
Synthesis of ethyl 2-((E)-4-oxo-2-((b-d-galactopyranosyl)
hydrazono)thiazolidinone-5-ylidene)acetate (3b)
Method A: To a well-stirred solution of b-d-galactopyrano-
sylthiosemicarbazone (4 mmol) in ethyl acetate (10 mL) and
water (5 mL) was added a solution of diethyl acetylene dicar-
boxylate (4 mmol) in small portions. The stirring was contin-
ued at ambient temperature for an additional 3 h. The
resulting mixture was filtered and recrystallized from EtOH
or DMF–H2O.
Method B: A mixture of b-d-galactopyranosylthiosemicar-
bazone (4 mmol) and DEADC (4 mmol) was subjected to
microwave irradiation at a power output of 200 W for 5–
7 min and after cooling the reaction mixture to room temper-
ature, the solid residue was recrystallized from EtOH or
DMF–H2O. The product was obtained as a yellow powder
(Scheme 3). Table 1 shows the reaction conditions and prod-
uct yields for the Aand B methods.
Ethyl 2-((E)-4-oxo-2-((b-d-glucopyranosyl)hydrazono)
thiazolidinone-5-ylidene)acetate (3d)
Yellow powder (recrystallized from EtOH or DMF–H2O);
25
mp 172–175 °C. ½aꢀ +0.1 (c 1.0, DMSO). FT-IR (KBr,
cm–1) ymax: 3212–32D97 (N–H), 2960–3088 (CH, aliphatic),
1
1767, 1665 (C=O), 1613, 1632 (C=N). H NMR (DMSO-
d6, 500 MHz), ppm) d: 9.14 (1H, NH), 6.95 (1H, HC=C–),
6.57 (1H, NH), 4.03–4.98 (m, 4H, OH), 5.03 (1H, H-1),
4.94 (1H, H-2), 4.62 (1H, H-3), 4.08 (1H, H-4), 3.91 (m,
1H, H-5), 3.98 (1H, H-6), 3.97 (1H, H-6′), 4.20 (q, 2H, J =
7.11 Hz, –CH2–), 1.21 (t, 3H, J = 7.10 Hz, –CH3). 13C NMR
(DMSO-d6, 125.77 MHz), ppm) d: 181.21, 177.90, 165.42
(C=O, NC=O, C=N), 148.27, 118.30 (C=C), 80.62 (C-1),
76.45 (C-5), 73.07 (C-2), 72.79 (C-3), 71.17 (C-4), 61.43,
60.63 (C-6, O–CH2), 14.18 (–CH3). Anal. calcd for
C12H17N3O8S (363.35) (%): C 39.67, H 4.72, N 11.56;
found: C 39.23, H 4.42, N 11.32.
Yellow powder (recrystallized from EtOH or DMF–H2O),
25
yield: 88%; mp 189–192 °C. ½aꢀD +1.0 (c 1.0, DMSO). FT-
IR (KBr, cm–1) ymax: 3200–3280 (N–H), 2955–3081 (CH,
aliphatic), 1766, 1666 (C=O), 1664, 1630 (C=N) and
1
(C=C). H NMR (DMSO-d6, 500 MHz), ppm) d: 9.85 (1H,
NH), 7.40 (1H, HC=C–), 6.60 (1H, NH), 3.53–5.06 (m, 4H,
OH), 4.90 (1H, H-1), 4.39 (1H, H-2) 4.23 (1H, H-3), 3.72
(1H, H-4), 3.68 (m, 1H, H-5), 3.85 (1H, H-6), 3.84 (1H, H-
6′) 4.23 (q, 2H, J = 7.14 Hz, –CH2–), 1.23 (t, 3H, J =
7.14 Hz, –CH3). 13C NMR (DMSO-d6, 125.77 MHz), ppm)
d: 168.07, 166.32, 165.74 (C=O, NC=O, C=N), 142.01,
114.53 (C=C), 82.83 (C-1), 76.83 (C-5), 74.20 (C-2), 73.20
(C-3), 70.69 (C-4), 61.66, 60.87 (C-6, –OCH2–), 14.02 (–CH3).
Anal. calcd for C13H19N3O8S (377.38) (%): C 40.38, H
5.07, N 11.13; found: C 40.22, H 5.11, N 11.45.
Methyl 2-((E)-4-oxo-2-((b-d-mannopyranosyl)hydrazono)
thiazolidinone-5-ylidene)acetate (3e)
Yellow powder (recrystallized from EtOH or DMF–H2O);
25
mp 184–186 °C. ½aꢀD –1.3 (c 0.5, DMSO). FT-IR (KBr,
cm–1) ymax: 3190–3280 (N–H), 2950–3080 (CH, aliphatic),
1
1765, 1663 (C=O), 1612, 1640 (C=N). H NMR (DMSO-
d6, 500 MHz), ppm) d: 9.60 (1H, NH), 7.11 (1H, NH), 6.95
(1H, HC=C–), 3.90–4.98 (m, 4H, OH), 5.60 (1H, H-1), 4.25
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