Nov-Dec 2005
Synthesis and Antitumor Activity of New Thiosemicarbazones
1279
3
8
.65-3.69 (t, 2H, d), 7.23-7.27 (q, 1H, 6) 8.06-8.09 (d, 1H, 7), 8.35-
.36 (d, 1H, 5), 9.18 (t, 1H, c), 10.69 (s, 1H, b), 13.41 (s, 1H, 3).
2-Acetylimidazo[4,5-b]pyridine-4-isobutyl-3-thiosemicarbazone
(A8).
Anal. Calcd. for C H N S (M.W. 262.33): C, 50.36; H, 5.38;
N, 32.04. Found: C, 50.04; H, 5.33; N, 31.34.
11 14 6
This compound was prepared by the general method given
above and purified with column chromatography (gradient from
CHCl 100% to CHCl /CH OH 95:5) to give the title compound
2
-Acetylimidazo[4,5-b]pyridine-4-n-propyl-3-thiosemicar-
3
3
3
in 75% yield; mp 209-209.7 °C; Rf : 0.41, Rf : 0.76, Rf : 0.31;
bazone (A4).
A
Γ
E
-
1
IR (cm , KBr): CH(-CH ) as 2961S, CH(-CH ) as 2930, SH
650vw C=N and C=C 1613S 1591s, C=S 1203S; H-NMR
3
2
This compound was prepared by the general method given
above to give the title compound in 74.5% yield; mp 213.8-214.4
1
2
(
300MHz, DMSO-d ): δ 0.92-0.94 (d, 6H, f), 2.03-2.12 (m, 1H,
6
-1
°
C; Rf : 0.61; IR (cm , KBr): CH(-CH ) 2965S, C=N and C=C
A 3
e), 2.43 (s, 1H, a), 3.44-3.49 (t, 2H, d), 7.23-7.28 (q, 1H, 6), 8.06
d, 1H, 7), 8.35-8.37 (d, 1H, 5), 9.19 (s, 1H,c), 10.67 (s, 1H, b),
3.48 (s, 1H, 3).
Anal. Calcd. for C H N S (M.W. 290.39): C, 53.77; H, 6.25;
1
1
0
3
8
619S 1587s, C=S 1208S; H-NMR (300MHz, DMSO-d ): δ
6
(
1
.90-0.95 (t, 3H, f), 1.61-1.69 (m, 2H, e), 2.42 (s, 3H, a), 3.56-
.63 (q, 2H, d), 7.23-7.27 (q, 1H, 6) 8.06-8.09 (d, 1H, 7), 8.35-
.36 (d, 1H, 5), 9.19 (t, 1H, c) 10.68 (s, 1H, b), 12.95 and 13.43
1
3 18 6
N, 28.94. Found: C, 53.46; H, 6.19; N, 28.44.
(
s, 1H, 3).
Anal. Calcd. for C H N S (M.W. 276.36): C, 52.15; H, 5.84;
N, 30.41. Found: C, 52.39; H, 5.83; N, 29.89.
2-Acetylimidazo[4,5-b]pyridine-4-tert-butyl-3-thiosemicar-
bazone (A9).
1
2 16 6
This compound was prepared by the general method given
above and purified with column chromatography (gradient from
2
-Acetylimidazo[4,5-b]pyridine-4-isopropyl-3-thiosemicar-
bazone (A5).
CHCl 100% to CHCl /CH OH 95:5) to give the title compound
3
3
3
This compound was prepared by the general method given
above and purified with column chromatography (gradient from
CHCl 100% to CHCl /CH OH 95:5) to give the title compound
in 72% yield; mp 223.5-224 °C; Rf : 0.61, Rf : 0.16; IR (cm ,
KBr): CH(-CH ) 2973S, SH 2640vw, C=N and C=C 1599S
-1
in 55% yield; mp 211.5-213 °C; Rf : 0.58; IR (cm , KBr): NH
298vs and 1369vs, C=S 1179S; H-NMR (300MHz, DMSO-d ):
B
1
3
6
3
3
3
δ 1.60 (s, 9H, d), 2.45 (s, 3H, a), 7.24-7.28 (q, 1H, 6), 8.04, (s, 1H,
c), 8.06-8.08 (d, 1H, 7), 8.36-8.38 (d, 1H, 5), 10.21 (s, 1H, b).
Anal. Calcd. for C H N S (M.W. 290.39): C, 53.77; H, 6.25;
-1
A
E
3
1
3 18 6
1
1
585s, C=S 1213S; H-NMR (300MHz, DMSO-d ): δ 1.27-1.29
6
N, 28.94. Found: C, 53.59; H, 6.30; N, 29.20.
(
d, 6H, e), 2.43 (s, 3H, a), 4.62-4.69 (m, 1H, d), 7.24-7.28 (q, 1H,
6
1
), 8.06-8.08 (d, 1H, 7), 8.36-8.38 (d, 1H, 5), 8.66 (s, 1H, c),
0.54 (s, 1H, b), 13.64 (s, 1H, 3).
2-Acetylimidazo[4,5-b]pyridine-4-allyl-3-thiosemicarbazone
(A10).
Anal. Calcd. for C H N S (M.W. 276.36): C, 52.15; H, 5.84;
N, 30.41. Found: C, 52.37; H, 5.85; N, 29.51.
1
2
16
6
This compound was prepared by the general method given
above and purified with column chromatography (gradient from
CHCl 100% to CHCl /CH OH 90:10) to give the title com-
2
(
-Acetylimidazo[4,5-b]pyridine-4-n-butyl-3-thiosemicarbazone
A6).
3
3
3
pound in 95% yield; mp 202-202.5 °C; Rf : 0.53, Rf : 0.78, Rf :
A
B
Γ
-
1
0
.61; IR (cm , KBr): NH 3304, C=C(alkene) 1680m, C=N and
C=C 1594s, 1541s, CH(-CH=CH), C=S 1197S; H-NMR
This compound was prepared by the general method given
1
above and purified with column chromatography (gradient from
CHCl 100% to CHCl /CH OH 95:5) to give the title compound
(
300MHz, DMSO-d ): δ 2.44 (s, 3H, a), 4.31-4.34 (t, 2H, d),
6
3
3
3
5.13-5.24 (m, 2H, g-f), 5.90-6.00 (m, 1H, e), 7.23-7.28 (q, 1H, 6),
8.04-8.07 (d, 1H, 7), 8.35-8.37 (d, 1H, 5), 9.29 (s, 1H, c), 10.82
in 79% yield; mp 206-207 °C; Rf : 0.23, Rf : 0.71; IR (cm-1,
A
E
KBr): CH 2959S, SH 2635w, C=N and C=C 1612S 1590s, C=S
(
s, 1H, b), 11.95 and 13.42 (s, 1H, 3).
1
1
196S; H-NMR (300MHz, DMSO-d ): δ 0.91-0.96 (t, 3H, g),
1
6
Anal. Calcd. for C H N S· ⁄ H O (M.W. 283.35): C, 50.87;
2
1
2
14
6
2
1
3
8
.32-1.40 (s, 2H, f), 1.57-1.67 (m, 2H, e), 2.42 (s, 3H, a), 3.60-
H, 5.34; N, 29.66. Found: C, 51.18; H, 5.32; N, 29.20.
.67 (q, 2H, d), 7.23-7.28 (q, 1H, 6), 8.05-8.07 (d, 1H, 7), 8.36-
.37 (d, 1H, 5), 9.14 (s, 1H, c), 10.68 (s, 1H, d), 13.42 (s, 1H, 3).
2
-Acetylimidazo[4,5-b]pyridine-4-cyclohexyl-3-thiosemicar-
Anal. Calcd. for C H N S (M.W. 290.39): C, 53.77; H, 6.25;
bazone (A11).
1
3 18 6
N, 28.94. Found: C, 53.15; H, 6.17; N, 28.17.
This compound was prepared by the general method given
above and recrystallised from 1-propanol to give the title com-
2
-Acetylimidazo[4,5-b]pyridine-4-sec-butyl-3-thiosemicar-
-1
pound in 76% yield; mp 218.6 °C; Rf : 0.58, Rf : 0.22; IR (cm ,
bazone (A7).
A
E
KBr): CH (ring)(sym) 2934vs, 2857s, SH 2635w, C=N and C=C
613s, 1594s, C=S 1203S (deformation vibrations of cyclo-
This compound was prepared by the general method given
above and purified with column chromatography (gradient from
CHCl 100% to CHCl /CH OH 95:5) to give the title compound
1
1
hexylo ring) 1026m and 1005m; H-NMR (300MHz, DMSO-
d6): δ 1.13-1.92 (m, 11H, ring), 2.43 (s, 3H, a), 7.24-7.28 (q, 1H,
6), 8.06-8.08 (d, 1H, 7), 8.36-8.38 (d, 1H, 5), 8.65 (s, 1H, c),
10.53 (s, 1H, b), 13.63 (s, 1H, 3).
3
3
3
in 65% yield; mp 230 °C; Rf : 0.64, Rf : 0.82, Rf : 0.68; IR
A
B
Γ
-1
(
cm , KBr): NH 3313vs, CH(CH ) as 2970S, CH(CH ) as 2930,
3 2
CH(-CH) (sym) 2875, SH 2635w, C=N and C=C 1579S, C=S
Anal. Calcd. for C H N S·H O (M.W. 334.44): C, 53.87; H,
1
5
20
6
2
1
1
1
205S; H-NMR (300MHz, DMSO-d ): δ 0.88-0.93 (t, 3H, g),
6
6.63; N, 25.13. Found: C, 54.22; H, 6.27; N, 24.83.
.23-1.25 (d, 3H, e), 1.65 (m, 2H, f), 2.44 (s, 3H, a), 4.49 (m, 1H,
2
-Acetylimidazo[4,5-b]pyridine-4,4-dimethyl-3-thiosemicar-
d), 7.27 (q, 1H, 6), 8.06-8.09 (d, 1H, 7), 8.36 (d, 1H, 5), 8.62 (s,
H, c), 10.52 (s, 1H,b), 13.61 (s, 1H, 3).
Anal. Calcd. for C H N S (M.W. 290.39): C, 53.77, H, 6.25,
bazone (A12).
1
This compound was prepared by the general method given
above and recrystallised from methanol to give the title
1
3 18 6
N, 28.94. Found: C, 52.60, H, 6.09, N, 28.38.