Synthesis and investigation of tuberculosis inhibition activities of some 1,2,3-triazole derivatives

Article abstract of DOI:10.1016/S0223-5234(02)01445-9

In this study, α-diazo-β-oxoaldehyde compounds were condensed with different amines to yield 4-acyl-1H-1,2,3-triazole derivatives. The 1,2,3-triazole compounds were investigated for their inhibition activities against tuberculosis.

Full text of DOI:10.1016/S0223-5234(02)01445-9

European Journal of Medicinal Chemistry 38 (2003) 215ꢂ218
/
www.elsevier.com/locate/ejmech
Preliminary communication
Synthesis and investigation of tuberculosis inhibition activities of
some 1,2,3-triazole derivatives
¨
Kadir Dabak *, Ozkan Sezer, Ahmet Akar, Olcay Anac
¸
Department of Chemistry, Faculty of Sciences, Istanbul Technical University, 80626 Maslak, Istanbul, Turkey
Received 15 May 2002; received in revised form 9 August 2002; accepted 9 September 2002
Abstract
In this study, a-diazo-b-oxoaldehyde compounds were condensed with different amines to yield 4-acyl-1H-1,2,3-triazole
derivatives. The 1,2,3-triazole compounds were investigated for their inhibition activities against tuberculosis.
´
# 2003 Editions scientifiques et me´dicales Elsevier SAS. All rights reserved.
Keywords: 1,2,3-Triazoles; Tuberculosis inhibition
1. Introduction
against tuberculosis (Table 1). a-diazo-b-oxoaldehyde
derivatives 1 were synthesised by Vilsmeier-Haack
formylation of 2-diazo-1-ethanone derivatives with
chloromethylene dimethyliminium chloride [4,5].
Compounds demonstrating at least 90% inhibition in
the primary screen are called ‘active’, and these com-
pounds can be tested further. It was found that 4-(2-
thiophenecarbonyl)-1-(bromoethyl)-1H-1,2,3-triazole
has 94% inhibition activity and therefore it is an active
compound against Mycobacterium tuberculosis H37Rv
[6].
Triazoles, like many other five membered heterocyclic
compounds are used very often in the pharmacological
and medicinal applications. Condensation of amine
derivatives with a-diazo-1,3-dicarbonyl compounds
gives 1H-1,2,3-triazole derivatives [1,2]. This is a simple
and regiospecific reaction and these make this method
superior to the widely used acylacetyleneꢀ
proach [3].
In this study, new 1,2,3-triazole derivatives were
prepared. These triazoles and the triazoles from our
previous work (2) were tested for their inhibition
activities against tuberculosis.
/azide ap-
3. Experimental part
2. Results
All diazo compounds were prepared as described in
Refs. [4] and [5]. Minimum inhibitory concentration
(MIC) is found by using Microplate Alamar Blue Assay
(MABA) in BACTEC 12B medium against Mycobacter-
ium tuberculosis H37Rv (6). M.p.: electrothermal glass-
bath apparatus in capillary tubes. IR (KBr, cmꢁ1):
Jasco FT-IR, model 5300. 1H-NMR and 13C-NMR
were recorded with a 200-MHz Bruker apparatus, in D6-
DMSO, in d (ppm) units, using TMS as internal
standard. Elemental analysis: LECO-CHNS 932 appa-
ratus.
Eight different a-diazo-b-oxoaldehyde derivatives 1
were condensed with aniline, p-chloroaniline, 1-amino-
naphthelene and 2-bromoethyl amine (Fig. 1) to yield 15
new and 5 known 1,2,3-triazole derivatives 2 in moder-
ate-to-good yields. 37 different 1,2,3-triazole com-
pounds were tested for their inhibition activities
* Correspondence and reprints.
E-mail address: kadird@eczacibasi.com.tr (K. Dabak).
´
0223-5234/03/$ - see front matter # 2003 Editions scientifiques et me´dicales Elsevier SAS. All rights reserved.
doi:10.1016/S0223-5234(02)01445-9

216
K. Dabak et al. / European Journal of Medicinal Chemistry 38 (2003) 215ꢂ218
/
triazoles precipitated. After recrystallization from
EtOH, products were obtained in pure form.
3.1.1. 4-(2-Thiophenecarbonyl)-1-(bromoethyl)-1H-
1,2,3-triazole (2.1)
Fig. 1.
Yield 65%. M.p.: 134ꢂ
1612, 1535, 1408, 1346, 1269, 1240, 1043, 1016, 943,
869, 825, 760, 698, 565, 461. 1H-NMR: 9.04 (s, HÃ
C(5));
/
136 8C. IR (cmꢁ1): 3126,
3.1. Synthesis of compounds 2.1ꢂ2.20
/
/
To a solution of appropriate compound 1 (10 mmol)
in 20 mL of EtOH, 10.1 mmol of the appropriate amine
compound and 10.1 mmol of AcOH were added. The
mixture was stirred at r.t. for 4 h. During this time, the
8.60 (d, 1 arom. H), 8.15 (d, 1 arom. H), 7.36 (t, 1 arom.
H), 4.94 (t, 2H), 4.06 (t, 2H). 13C-NMR: 176.52, 146.01,
141.69, 136.17, 135.65, 129.59, 128.77, 51.18, 30.98.
C9H8BrN3OS.
Table 1
Tuberculosis inhibition test results
a
b
Compound 1 & 2
R
R?
MIC (mg mLꢁ1
)
Inhibition (%)
Activity
c
2.1 [7]
thiophene-2-yl
2,5-Me2-furan-3-yl
furan-2-yl
BrCH2CH2
C6H5
C6H5
B
/
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
94
82
42
22
19
17
0
ꢀ
/
c
2.2
2.3
ꢀ
/
ꢁ
/
c
ꢀ
/
ꢁ
/
c
2.4 [8]
c
2.5
2.6
C6H5
naphth-1-yl
C6H5
ꢀ
/
ꢁ
/
4-BrÃ/C6H4
ꢀ
/
ꢁ
/
c
furan-2-yl
C6H5
4-ClÃ
4-ClÃ
/
C6H4
C6H4
ꢀ
/
ꢁ
/
c
2.7 [9]
c
2.8
2.9
/
ꢀ
/
ꢁ
/
naphth-2-yl
naphth-2-yl
naphth-1-yl
4-ClÃC6H4
naphth-1-yl
4-ClÃC6H4
naphth-1-yl
4-ClÃC6H4
naphth-1-yl
ꢀ
/
0
ꢁ
/
c
/
ꢀ
/
0
ꢁ
/
c
2.10
2.11
2,4-Cl2Ã
/
C6H3
ꢀ
/
0
ꢁ
/
c
2,4-Cl2Ã
/
C6H3
/
ꢀ
/
0
ꢁ
/
c
2.12
2.13
i-Pr
i-Pr
ꢀ
/
0
ꢁ
/
c
/
ꢀ
/
0
ꢁ
/
c
2.14
2.15
thiophene-2-yl
thiophene-2-yl
ꢀ
/
0
ꢁ
/
c
4-ClÃ
/
C6H4
ꢀ/
0
ꢁ/
c
2.16
2.17
4-BrÃ
/
C6H4
4-ClÃ
4-ClÃ
C6H5
4-ClÃ
4-ClÃ
C6H5
C6H5
C6H5
C6H5
C6H5
H
/
C6H4
C6H4
ꢀ
/
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
12.5
0
0
ꢁ
/
c
2,5-Me2-furan-3-yl
/
ꢀ
/
ꢁ
/
c
2.18 [1,10]
c
2.19 [11]
EtO
EtO
ꢀ
/
0
ꢁ
/
/
C6H4
C6H4
ꢀ
/
0
ꢁ
/
c
2.20
2.21
4-MeOÃ
/
C6H4
/
ꢀ
/
0
ꢁ
/
d
naphth-1-yl
i-Bu
i-Pr
ꢀ
/
83
78
50
49
29
29
24
14
12
10
5
ꢁ
/
d
2.22
2.23
ꢀ
/
ꢁ
/
d
ꢀ
/
ꢁ
/
d
2.24
2.25
2,4-Cl2Ã
/
C6H3
C6H3
ꢀ
/
ꢁ
/
d
2,4-Br2Ã
/
ꢀ
/
ꢁ
/
d
2.26
2.27
EtO
ꢀ
/
ꢁ
/
d
4-ClÃ
/
C6H4
C6H5
H
ꢀ
/
ꢁ
/
d
2.28
2.29
Me
Me
ꢀ
/
ꢁ
/
d,e
OH
ꢀ
/
ꢁ
/
d
2.30
2.31
2,4,6-Me3Ã
Me
3,4-Cl2Ã
2,4-Cl2Ã
2,4-Br2Ã
EtO
/C6H3
C6H5
C6H5
C6H5
H
ꢀ
/
ꢁ
/
d
ꢀ
/
ꢁ
/
d
2.32
2.33
/C6H3
ꢀ
/
0
ꢁ
/
d
/C6H3
ꢀ
/
0
ꢁ
/
d
2.34
2.35
/
C6H3
C6H3
H
OH
ꢀ
/
0
ꢁ
/
d
ꢀ
/
0
ꢁ
/
d,e
2.36
2.37
2,4-Br2Ã
EtO
/
OH
ꢀ
/
0
ꢁ
/
d
Ã
/
NHCONH2
ꢀ/
0
ꢁ/
a
MIC is found by using MABA in BACTEC 12B medium against Mycobacterium tuberculosis H37Rv (6).
Compounds demonstrating at least 90% inhibition in the primary screen are called ‘active’, and these compounds can be tested further.
b
c
These compounds were synthesised in this work.
These compounds were synthesised in our previous work [2].
In oxime form.
d
e

K. Dabak et al. / European Journal of Medicinal Chemistry 38 (2003) 215ꢂ
/218
217
3.1.2. 4-(2,5-Dimethyl-3-furancarbonyl)-1-phenyl-1H-
1,2,3-triazole (2.2)
3.1.8. 4-(2-Naphthoyl)-1-(napht-1-yl)-1H-1,2,3-triazole
(2.8)
Yield 82%. M.p.: 192ꢂ
/
194 8C. IR (cmꢁ1): 1639,
1556, 1500, 1442, 1283, 1008, 879, 821, 507. H-NMR:
Yield 55%. M.p.: 161ꢂ
3057, 1635, 1597, 1523, 1471, 1361, 1280, 1238, 1124,
7.64 (m,
/
163 8C. IR (cmꢁ1): 3126,
1
9.46 (s, HÃ
/
C(5)), 8.02ꢂ
/
7.51 (m, 5 arom. H), 7.11 (s, 1
906, 777, 760. 1H-NMR: 9.42 (s, HÃ
/
C(5)), 8.72ꢂ
/
arom. H (furan)), 2.57 (s, CH3), 2.30 (s, CH3). 13C-
NMR: 197.87, 158.97, 149.70, 148.44, 136.04, 129.84,
129.26, 126.74, 120.61, 120.11, 107.27, 14.24, 12.81.
C15H13N3O2.
14 arom. H). 13C-NMR: 184.95, 146.56, 135.08, 133.85,
133.57, 132.59, 132.27, 131.97, 130.75, 129.82, 128.86,
128.31, 128.24, 128.16, 127.83, 127.66, 127.22, 126.98,
125.37, 125.09, 124.36, 122.01. C23H15N3O.
3.1.3. 4-(2-Furancarbonyl)-1-phenyl-1H-1,2,3-triazole
(2.3)
3.1.9. 4-(2-Naphthoyl)-1-(p-chlorophenyl)-1H-1,2,3-
triazole (2.9)
Yield 80%. M.p.: 198ꢂ
/
201 8C. IR (cmꢁ1): 3140,
1643, 1564, 1531, 1466, 1396, 1286, 1199, 1087, 1028,
Yield 50%. M.p.: 233ꢂ
/
235 8C. IR (cmꢁ1): 3134,
3105, 3059, 1628, 1523, 1504, 1358, 1278, 1236, 1097,
1
1
945, 862, 763, 750. H-NMR: 9.66 (s, HÃ
/
C(5)), 8.18ꢂ
/
1012, 987, 906, 833. H-NMR: 9.69 (s, HÃ
/
C(5)), 8.13ꢂ
/
7.56 (m, 7 arom. H), 7.86 (s, 1 arom. H (furan)). 13C-
NMR: 171.22, 150.40, 148.96, 146.09, 141.29, 135.99,
129.87, 129.34, 127.18, 122.35, 120.64, 112.89, 109.17.
C13H9N3O2.
7.73 (m, 11 arom. H). 13C-NMR: 183.91, 149.87, 141.03,
137.77, 137.00, 134.68, 131.53, 127.19, 127.50, 126.37.
C19H12ClN3O.
3.1.10. 4-(2?,4?-Dichlorobenzoyl)-1-(napht-1-yl)-1H-
1,2,3-triazole (2.10)
3.1.4. 4-(Benzoyl)-1-(napht-1-yl)-1H-1,2,3-triazole
(2.4)
Yield 65%. M.p.: 189ꢂ
/
192 8C. IR (cmꢁ1): 3123,
1638, 1583, 1523, 1277, 1242, 999, 904, 800, 769. H-
1
Yield 60%. M.p.: 141ꢂ
/
142 8C. IR (cmꢁ1): 3121,
3047, 1641, 1597, 1575, 1521, 1273, 1253, 1168, 906,
NMR: 9.53 (s, HÃ
/
C(5)), 8.27ꢂ7.48 (m, 10 arom. H).
/
1
767. H-NMR: 9.46 (s, HÃ
/
C(5)), 8.14ꢂ
/
8.35 (m, 4 arom.
7.88 (m, 8 arom. H). 13C-NMR: 146.43,
13C-NMR: 185.33, 146.10, 136.35, 136.09, 133.52,
132.32, 131.53, 131.46, 130.88, 129.64, 128.33, 128.22,
127.75, 127.41, 127.26, 125.34, 124.40, 121.80.
C19H11Cl2N3O.
H), 7.53ꢂ
/
136.55, 133.52, 133.32, 132.53, 132.39, 130.72, 129.94,
128.54, 128.27, 128.13, 127.82, 127.18, 125.32, 124.33,
121.93. C19H13N3O.
3.1.11. 4-(2?,4?-Dichlorobenzoyl)-1-(p-chlorophenyl)-
1H-1,2,3-triazole (2.11)
3.1.5. 4-(4?-Bromobenzoyl)-1-phenyl-1H-1,2,3-triazole
(2.5)
Yield 80%. M.p.: 219ꢂ
/
222 8C. IR (cmꢁ1): 3126,
3101, 3086, 1635, 1587, 1523, 1502, 1244, 1043, 910,
Yield 90%. M.p.: 177ꢂ
178 8C. IR (cmꢁ1): 3130,
3067, 1637, 1581, 1562, 1525, 1398, 1354, 1267, 1180,
/
1
841, 688. H-NMR: 9.66 (s, HÃ
/
C(5)), 8.07-7.60 (m, 7
arom. H). 13C-NMR: 185.20, 146.68, 136.12, 134.67,
133.86, 131.45, 131.25, 129.88, 129.61, 127.45, 122.42.
C15H8Cl3N3O.
1
1008, 904, 868, 754, 686, 584, 464, 414. H-NMR: 9.61
(s, HÃ
/
C(5)), 8.26ꢂ
7.57 (m, 9 arom. H). 13C-NMR:
183.92, 146.88, 135.34, 131.62, 129.84, 129.35, 128.05,
127.54, 120.64. C15H10BrN3O.
/
3.1.12. 4-(2-Methylpropanoyl)-1-(napht-1-yl)-1H-
1,2,3-triazole (2.12)
3.1.6. 4-(2-Furancarbonyl)-1-(p-chlorophenyl)-1H-
1,2,3-triazole (2.6)
Yield 75%. M.p.: 186ꢂ
3053, 3018, 1649, 1606, 1533, 1278, 995, 908, 790, 756.
C(5)), 8.29-7.43 (m, 7 arom. H),
/
189 8C. IR (cmꢁ1): 3124,
Yield 76%. M.p.: 141ꢂ
1641, 1562, 1533, 1466, 1390, 1286, 1203, 1024, 1006,
985, 939, 841, 592, 513, 472. 1H-NMR: 9.66 (s, HÃ
C(5)),
8.63ꢂ
7.36 (m, 7 arom. H). 13C-NMR: 176.54, 147.07,
/
142 8C. IR (cmꢁ1): 3130,
1H-NMR: 9.43 (s, HÃ
/
/
3.66 (septet, CH); 1.20 (d, CH3). 13C-NMR: 184.57,
146.62, 143.89, 133.95, 133.53, 132.56, 132.24, 130.71,
130.13, 129.14, 128.28, 128.13, 127.82, 127.19, 125.33,
124.32, 121.93, 25.03, 21.19. C16H15N3O.
/
141.98, 136.78, 134.01, 130.12, 129.22, 122.69.
C13H8ClN3O2.
3.1.7. 4-(Benzoyl)-1-(p-chlorophenyl)-1H-1,2,3-triazole
(2.7)
3.1.13. 4-(2-Methylpropanoyl)-1-(p-chlorophenyl)-1H-
1,2,3-triazole (2.13)
Yield 85%. M.p.: 215ꢂ
/
220 8C. IR (cmꢁ1): 3126,
30101, 3088, 3057, 1639, 1599, 1575, 1521, 1502, 1408,
Yield 70%. M.p.: 221ꢂ
/
223 8C. IR (cmꢁ1): 3124,
1637, 1606, 1568, 1267, 1170, 904, 841. H-NMR: 9.59
1
1344, 1265, 1170, 1014, 841, 819, 735. 1H-NMR: 9.62 (s,
(s, HÃ
/
C(5)), 8.21ꢂ7.40 (m, 4 arom. H), 3.65 (septet,
/
HÃ
/
C(5)), 7.42ꢂ
/
8.28 (m, 9 arom. H). 13C-NMR: 147.07,
CH), 1.19 (d, CH3). 13C-NMR: 184.42, 147.28, 143.99,
134.86, 133.81, 133.67, 130.10, 129.84, 129.16, 122.41,
21.19. C12H12ClN3O.
136.37, 134.80, 133.66, 133.37, 130.50, 129.89, 129.81,
128.54, 128.09, 122.38. C15H10ClN3O.

218
K. Dabak et al. / European Journal of Medicinal Chemistry 38 (2003) 215ꢂ
/218
1
3.1.14. 4-(2-Thiophenecarbonyl)-1-(napht-1-yl)-1H-
1,2,3-triazole (2.14)
1039, 837, 769, 516, 459. H-NMR: 9.51 (s, HÃ
/
C(5)),
8.03 (d, 2 arom. H), 7.70 (d, 2 arom. H), 4.36 (q,CH2),
1.34 (t, CH3). 13C-NMR: 159.93, 139.79, 134.79, 133.55,
129.76, 127.25, 122.17, 60.72, 14.08. C11H10ClN3O2.
Yield 65%. M.p.: 185ꢂ
/
189 8C. IR (cmꢁ1): 3119,
1618, 1535, 1413, 1277, 1037, 997, 877, 833, 570, 424.
1H-NMR: 9.48 (s, HÃ
/
C(5)), 8.69ꢂ7.37 (m, 10 arom. H).
/
13C-NMR: 176.45, 146.16, 141.85, 136.38, 135.89,
133.54, 132.51, 131.83, 130.78, 128.91, 128.30, 128.18,
127.79, 127.21, 125.34, 124.36, 121.88. C17H11N3OS.
3.1.20. 4-(4?-Methoxybenzoyl)-1-(p-chlorophenyl)-1H-
1,2,3-triazole (2.20)
Yield 87%. M.p.: 217ꢂ
/
219 8C. IR (cmꢁ1): 3124,
1639, 1523, 1504, 1267, 1170, 1014, 904, 841, 754, 625,
3.1.15. 4-(2-Thiophenecarbonyl)-1-(p-chlorophenyl)-
1H-1,2,3-triazole (2.15)
1
468. H-NMR: 9.58 (s, HÃ
/
C(5)), 8.09ꢂ7.40 (m, 8 arom.
/
Yield 75%. M.p.: 246ꢂ
/
252 8C. IR (cmꢁ1): 3130,
1618, 1533, 1502, 1269, 1170, 1041, 829, 715, 509. H-
H). 13C-NMR: 184.43, 147.30, 144.01, 134.86, 133.81,
133.68, 130.11, 129.86, 129.18, 127.94, 122.41.
C16H12ClN3O2.
1
NMR: 9.65 (s, HÃ
/
C(5)), 8.62ꢂ
7.35 (m, 7 arom. H). 13C-
NMR: 176.25, 146.79, 141.70, 136.47, 135.90, 134.79,
133.73, 129.83, 128.91, 127.55, 122.40. C13H8ClN3OS.
/
3.1.16. 4-(4?-Bromobenzoyl)-1-(p-chlorophenyl)-1H-
1,2,3-triazole (2.16)
Acknowledgements
Yield 88%. M.p.: 219ꢂ
/
221 8C. IR (cmꢁ1): 3489,
1647, 1583, 1502, 1267, 1003, 900, 837, 760, 516. H-
1
The authors are grateful for the biological tests of
‘Tuberculosis Antimicrobial Acquisition and Coordinat-
ing Facility (Colorado State University)’ and for the
financial support of Istanbul Technical University.
NMR: 9.66 (s, HÃ
/
C(5)), 8.24-7.71 (m, 8 arom. H). 13C-
NMR: 183.89, 146.92, 135.31, 134.76, 133.75, 131.88,
131.68, 129.85, 128.33, 127.62, 122.41. C15H9BrClN3O.
3.1.17. 4-(2,5-Dimethyl-3-furancarbonyl)-1-(p-
chlorophenyl)-1H-1,2,3-triazole (2.17)
Yield 78%. M.p.: 120ꢂ
2961, 1639, 1614, 1564, 1523, 1386, 1358, 1232, 1213,
1012, 999, 925, 877, 761, 688, 572. 1H-NMR: 9.47 (s, HÃ
/
123 8C. IR (cmꢁ1): 3119,
References
/
[1] D. Clarke, R.W. Mares, H. McNab, J. Chem. Soc. Chem.
C(5)), 7.60 (m, 4 arom. H), 7.12 (s, furan arom. H), 2.59
(s, CH3), 2.32 (s, CH3). 13C-NMR: 179.84, 158.91,
149.65, 148.42, 136.03, 129.80, 129.22, 126.64, 120.58,
120.10, 107.25, 14.20, 12.77. C15H12ClN3O2.
Commun. (1993) 1026.
¨
[2] O. Sezer, K. Dabak, O. Anac, A. Akar, Helv. Chim. Acta 79
¸
(1996) 449.
[3] T.L. Gilchrist, G.E. Geymer, in: A.R. Katritzky, A.J. Boulton
(Eds.), Advances in Heterocyclic Chemistry, vol. 16, Academic
Press, New York, 1974, p. 33.
3.1.18. 4-(Ethylcarboxylate)-1-phenyl-1H-1,2,3-triazole
(2.18)
[4] F.M. Stojanovic, Z. Arnold, Collect. Czech. Chem. Commun. 32
(1967) 2155.
Yield 85%. M.p.: 84ꢂ
/
86 8C. IR (cmꢁ1): 3140, 1712,
1597, 1548, 1508, 1469, 1375, 1269, 1170, 1039, 869, 839,
¨
[5] O. Sezer, K. Dabak, O. Anac, A. Akar, Helv. Chim. Acta 80
¸
(1997) 960.
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1
765, 688, 507. H-NMR: 9.50 (s, HÃ
/
C(5)), 7.99 (d, 2
arom. H), 7.66ꢂ7.54 (m, 3 arom. H), 4.37 (q, CH2), 1.35
/
[7] K. Dabak, A. Akar, Heterocycl. Commun. 8 (1) (2002) 61ꢂ64.
/
(t, CH3). 13C-NMR: 160.04, 139.71, 135.99, 129.81,
129.21, 127.12, 120.45, 60.68, 14.10. C11H11N3O2.
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Perkin Trans. 1 15 (1993) 1719.
3.1.19. 4-(Ethylcarboxylate)-1-(p-chlorophenyl)-1H-
1,2,3-triazole (2.19)
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S. Ali, J. Heterocycl. Chem. 26 (5) (1989) 1461.
Yield 87%. M.p.: 170ꢂ
/
172 8C. IR (cmꢁ1): 3151,
2980, 1720, 1552, 1500, 1369, 1342, 1267, 1163, 1091,
[11] G. L’abbe, M. Bruynseels, P. Delbeke, S. Toppet, J. Heterocycl.
Chem. 27 (7) (1990) 2021.