H
L. Le Corre et al.
Paper
Synthesis
MS (ESI): m/z = 342 [M + H]+.
HRMS (ESI): m/z [M + H]+ calcd for C15H1179BrN5O3S: 419.9760; found:
419.9753.
HRMS (ESI): m/z [M – H]– calcd for C15H10N5O3S: 340.0510; found:
340.0503.
Methyl 1-(3-Chlorophenyl)-3-cyano-4-(2-imino-4-oxothiazolidin-
3-yl)-1H-pyrazole-5-carboxylate (5e)
Methyl 1-(3-Methoxyphenyl)-3-cyano-4-(2-imino-4-oxothiazoli-
According to GP IV, thiazolidin-4-one 5e was obtained from pyrazole
4e (100 mg, 0.28 mmol) in acetone (1.8 mL). Flash chromatography
(cyclohexane/EtOAc, 1:1) afforded 5e as a white solid (77 mg, 72%);
mp (dec.); Rf = 0.13 (cyclohexane/EtOAc, 1:1).
din-3-yl)-1H-pyrazole-5-carboxylate (5b)
According to GP IV, thiazolidin-4-one 5b was obtained from pyrazole
4b (80 mg, 0.23 mmol) in acetone (1.2 mL). Flash chromatography
(cyclohexane/EtOAc, 1:1) afforded 5b as a yellow solid (60 mg, 70%);
mp (dec.); Rf = 0.14 (cyclohexane/EtOAc, 1:1).
IR (ATR): 3320 (NH), 2248 (C≡N), 1721 (ester C=O), 1634 (amide C=O,
C=N), 1587, 1552, 1481, 1347, 1310, 1240, 1130, 1043 cm–1
.
IR (ATR): 3300 (NH), 2952, 2923, 2248 (C≡N), 1740 (ester C=O), 1631
(amide C=O, C=N), 1607, 1493, 1369, 1295, 1233, 1127, 1026 cm–1
.
1H NMR: δ = 9.76 (s, 1 H, NH), 7.91–7.86 (m, 1 H, H-2′), 7.71–7.56 (m,
3 H, H-4′, H-5′, H-6′), 4.37 (s, 2 H, H-5′′), 3.71 (s, 3 H, CO2CH3).
13C NMR: δ = 170.4 (C-4′′), 156.6 (CO2CH3), 155.7 (C-2′′), 139.6 (C-1′),
133.2 (C-3′), 130.9 (Cpyr), 130.6 (CH), 130.2 (CH), 125.9 (C-2′), 124.7
(C-6′), 124.3 (Cpyr), 123.4 (Cpyr), 111.1 (C≡N), 53.0 (OCH3), 33.7 (C-5′′).
MS (ESI): m/z = 376 [M + H]+.
HRMS (ESI): m/z [M + H]+ calcd for C15H1135ClN5O3S: 376.0266; found:
1H NMR: δ = 9.74 (s, 1 H, NH), 7.49–7.43 (m, 1 H, H-5′), 7.26–7.22 (m,
1 H, H-2′), 7.19–7.12 (m, 2 H, H-4′, H-6′), 4.38 (s, 2 H, H-5′′), 3.82 (s, 3
H, OCH3), 3.70 (s, 3 H, OCH3).
13C NMR: δ = 170.4 (C-4′′), 159.5 (C-3′), 156.7 (CO2CH3), 155.8 (C-2′′),
139.6 (C-1′), 130.9 (Cpyr), 129.9 (C-5′), 123.9 (Cpyr), 123.3 (Cpyr), 117.8
(C-6′), 116.2 (C-4′), 111.2 (2 C, C-2′, C≡N), 55.7 (OCH3), 53.0 (CO2CH3),
33.7 (C-5′′).
376.0261.
MS (ESI): m/z = 372 [M + H]+.
HRMS (ESI): m/z [M + H]+ calcd for C16H14N5O4S: 372.0761; found:
Methyl 1-(4-Chlorophenyl)-3-cyano-4-(2-imino-4-oxothiazolidin-
3-yl)-1H-pyrazole-5-carboxylate (5f)
372.0753.
According to GP IV, thiazolidin-4-one 5f was obtained from pyrazole
4f (81 mg, 0.23 mmol) in acetone (3.5 mL). Flash chromatography (cy-
clohexane/EtOAc, 1:1) afforded 5f as a white solid (42 mg, 49%); mp
174–176 °C; Rf = 0.19 (cyclohexane/EtOAc, 3:2).
Methyl 1-(3-Bromophenyl)-3-cyano-4-(2-imino-4-oxothiazolidin-
3-yl)-1H-pyrazole-5-carboxylate (5c)
According to GP IV, thiazolidin-4-one 5c was obtained from pyrazole
4c (150 mg, 0.38 mmol) in acetone (2.4 mL). Flash chromatography
(cyclohexane/EtOAc, 1:1) afforded 5c as a white solid (106 mg, 67%);
mp 158–160 °C; Rf = 0.18 (cyclohexane/EtOAc, 3:2).
IR (ATR): 3313 (NH), 2926, 2850, 2251 (C≡N), 1741 (ester C=O), 1619
(amide C=O, C=N), 1495, 1441, 1371, 1293, 1243, 1181, 1138, 1035,
1013 cm–1
.
IR (ATR): 3300 (NH), 2926, 2251 (C≡N), 1742 (ester C=O), 1619 (amide
1H NMR: δ = 9.75 (s, 1 H, NH), 7.72–7.68 (m, 2 H, H-2′, H-6′), 7.66–
7.62 (m, 2 H, H-3′, H-5′), 4.38 (s, 2 H, H-5′′), 3.71 (s, 3 H, OCH3).
C=O, C=N), 1480, 1371, 1270, 1197, 1144, 1120, 1040 cm–1
.
1H NMR: δ = 9.76 (s, 1 H, NH), 7.99 (t, J = 2.0 Hz, 1 H, H-2′), 7.80 (dd,
J = 8.0, 2.0 Hz, 1 H, H-4′), 7.67 (dd, J = 7.5, 2.0 Hz, 1 H, H-6′), 7.52 (dd,
J = 8.0, 7.5 Hz, 1 H, H-5′), 4.38 (s, 2 H, H-5′′), 3.71 (s, 3 H, OCH3).
13C NMR: δ = 170.4 (C-4′′), 156.7 (CO2CH3), 155.7 (C-2′′), 137.4 (C-1′),
134.7 (C-4′), 130.9 (Cpyr), 129.1 (2 C, C-2′, C-6′), 127.6 (2 C, C-3′, C-5′),
124.2 (Cpyr), 123.5 (Cpyr), 111.9 (C≡N), 53.0 (OCH3), 33.7 (C-5′′).
13C NMR: δ = 170.4 (C-4′′), 156.6 (CO2CH3), 155.7 (C-2′′), 139.7 (C-1′),
133.1 (C-4′), 130.9 (Cpyr), 130.8 (C-5′), 128.6 (C-2′), 125.1 (C-6′), 124.3
(Cpyr), 123.4 (Cpyr), 121.3 (C-3′), 111.1 (C≡N), 53.0 (OCH3), 33.7 (C-5′′).
MS (ESI): m/z = 376 [M + H]+.
HRMS (ESI): m/z [M + H]+ calcd for C15H1135ClN5O3S: 376.0266; found:
376.0261.
MS (ESI): m/z = 420, 422 [M + H]+.
HRMS (ESI): m/z [M – H]– calcd for C15H979BrN5O3S: 417.9615; found:
Methyl 1-(3-Fluorophenyl)-3-cyano-4-(2-imino-4-oxothiazolidin-
3-yl)-1H-pyrazole-5-carboxylate (5g)
417.9623.
According to GP IV, thiazolidin-4-one 5g was obtained from pyrazole
4g (190 mg, 0.56 mmol) in acetone (3.5 mL). Flash chromatography
(cyclohexane/EtOAc, 1:1) afforded 5g as a white solid (99 mg, 49%);
mp 144–146 °C; Rf = 0.17 (cyclohexane/EtOAc, 3:2).
Methyl 1-(4-Bromophenyl)-3-cyano-4-(2-imino-4-oxothiazolidin-
3-yl)-1H-pyrazole-5-carboxylate (5d)
According to GP IV, thiazolidin-4-one 5d was obtained from pyrazole
4d (100 mg, 0.25 mmol) in acetone (1.5 mL). Flash chromatography
(cyclohexane/EtOAc, 1:1) afforded 5d as a white solid (51 mg, 49%);
mp 182–184 °C; Rf = 0.21 (cyclohexane/EtOAc, 3:2).
IR (ATR): 3305 (NH), 3086, 2924, 2246 (C≡N), 1738 (ester C=O), 1633
(amide C=O, C=N), 1611, 1490, 1460, 1437, 1371, 1297, 1258, 1216,
1197, 1124, 1110, 1037, 903, 734 cm–1
.
IR (ATR): 3289 (NH), 2927, 2252 (C≡N), 1735 (ester C=O), 1616 (amide
1H NMR: δ = 9.75 (s, 1 H, NH), 7.72–7.67 (m, 1 H, H-2′), 7.64–7.57 (m,
1 H, H-5′), 7.52–7.43 (m, 2 H, H-6′, H-4′), 4.37 (s, 2 H, H-5′′), 3.71 (s, 3
H, OCH3).
C=O, C=N), 1492, 1440, 1372, 1295, 1247, 1201, 1142, 1110, 1070,
1034, 1011 cm–1
.
1H NMR: δ = 9.75 (s, 1 H, NH), 7.77 (d, J = 8.5 Hz, 2 H, H-3′, H-5′), 7.55
(d, J = 8.5 Hz, 2 H, H-2′, H-6′), 4.38 (s, 2 H, H-5′′), 3.71 (s, 3 H, OCH3).
13C NMR: δ = 170.4 (C-4′′), 156.7 (CO2CH3), 155.7 (C-2′′), 137.8 (C-1′),
132.0 (2 C, C-2′, C-6′), 130.8 (Cpyr), 127.8 (2 C, C-3′, C-5′), 124.2 (Cq),
123.5 (Cq), 123.3 (Cq), 111.1 (C≡N), 53.0 (OCH3), 33.7 (C-5′′).
13C NMR: δ = 170.4 (C-4′′), 161.5 (d, JC,F = 246.0 Hz, C-3′), 156.6
(CO2CH3), 155.8 (C-2′′), 139.7 (d, JC,F = 11.0 Hz, C-1′), 131.0 (Cpyr), 130.8
(d, JC,F = 9.0 Hz, C-5′), 124.3 (Cpyr), 123.5 (Cpyr), 122.1 (C-6′), 117.2 (d,
JC,F = 21.0 Hz, C-4′), 113.6 (d, JC,F = 26.5 Hz, C-2′), 111.7 (C≡N), 53.5
(OCH3), 33.7 (C-5′′).
MS (ESI): m/z = 358 [M – H]–.
MS (ESI): m/z = 420, 422 [M + H]+.
© Georg Thieme Verlag Stuttgart · New York — Synthesis 2016, 48, A–K