Synthesis and antifungal activity of novel triazole derivatives

Article abstract of DOI:10.1007/s12272-011-1009-z

A series of novel azoles (a-v), which are analogues of fluconazole, have been designed and synthesized as potential antifungal agents by the click reaction. The click reaction approach toward the synthesis of novel 1,2,3-triazolyl linked triazole antifungal derivatives a-v was achieved by Cu(I)-catalyzed 1,3-dipolar cycloaddition of propargylated intermediate 5 with substituted azidomethyl benzene. In addition, the target compounds tested can increase antifungal activity.

Full text of DOI:10.1007/s12272-011-1009-z

Arch Pharm Res Vol 34, No 10, 1649-1656, 2011
DOI 10.1007/s12272-011-1009-z
Synthesis and Antifungal Activity of Novel Triazole Derivatives
Yongzheng Yan, Shichong Yu, Xiaoyun Chai, Honggang Hu, and Qiuye Wu
Department of Organic Chemistry, College of Pharmacy, Second Military Medical University, Guohe Road 325, Shang-
hai 200433, China
(Received February 19, 2011/Revised June 27, 2011/Accepted July 13, 2011)
A series of novel azoles (a-v), which are analogues of fluconazole, have been designed and syn-
thesized as potential antifungal agents by the click reaction. The click reaction approach
toward the synthesis of novel 1,2,3-triazolyl linked triazole antifungal derivatives
a
-
v
5
was
with
achieved by Cu(I)-catalyzed 1,3-dipolar cycloaddition of propargylated intermediate
substituted azidomethyl benzene. In addition, the target compounds tested can increase anti-
fungal activity.
Key words: Azole, Click reaction, Antifungal activity, CYP51
INTRODUCTION
Fungal infections have become an important compli-
cation and a major cause of morbidity and mortality in
immunocompromised individuals suffering from tuber-
culosis, cancer, or AIDS and in organ transplant cases
(Fridkin and Jarvis, 1996; Wingard and Leather, 2004).
Several clinical drugs, such as azoles, amphotericin B,
5-fluorocytosine, and caspofungin, have been developed
to reduce the impact of fungal diseases. Among those,
azoles, especially triazole antifungal agents, have been
used widely and efficiently. For example, fluconazole,
voriconazole, and itraconazole (Fig. 1) presently play a
leading role in the treatment of invasive fungal infec-
tions. Triazole antifungals (e.g. fluconazole and vori-
conazole), which act by inhibiting lanosterol cytochrome
Fig. 1. Triazole antifungal agents used in clinical therapy
P450 14
α-demethylase (CYP51), have now become the
most rapidly expanding group of antifungal compounds. structure-activity of the inhibition of CYP51 should be
However, current antifungal therapy suffers from drug- further studied.
related toxicity, severe drug resistance, non-optimal
Azoles exert antifungal activity through inhibition
pharmacokinetics, and serious drug-drug interactions of CYP51 by a mechanism in which the heterocyclic
(Latgé, 1999; Steenbergen and Casadevall, 2000). That nitrogen (N-3 of imidazole or N-4 of 1,2,4-tiazole) binds
situation highlights the need for advent of safe, novel, to the sixth coordination of heme iron atom of the
and effective antifungal compounds. In addition, the porphyrin in the substrate binding site of the enzyme
(Trzaskos et al., 1986; Aoyama et al., 1987). Based on
the structure of the active site of CYP51 and extensive
investigation of the structure-activity relationships
Correspondence to: Qiuye Wu and Honggang Hu, Department
of Organic Chemistry, College of Pharmacy, Second Military
(SAR) of azole antifungals, it was found that the tri-
azole ring, the difluorophenyl group, and the hydroxyl
group were the pharmacophores of antifungal agents.
The side chains located in the narrow hydrophobic
Medical University, Guohe Road 325, Shanghai 200433, China
Tel, Fax: 86-21-8187-1225
E-mail: wuqy6439@sohu.com (Q. Wu), huhonggang_fox@msn.com
(H. Hu)
1649

1650
Y. Yan et al.
interact with the narrow hydrophobic cleft, to explore
how it may further affect antifungal activity.
MATERIALS AND METHODS
1H- and 13C-NMR (Nuclear magnetic resonance) spec-
tra were recorded in CDCl3 unless otherwise indicated
with a Bruker AC-300P spectrometer, using TMS
(Tetramethylsilane) as internal standard. The HPLC-
MS (High Performance Liquid Chromatography-Mass
Spectrometry) were recorded on Agilent 1100 series
LC-MS. The solvents and reagents were purchased
from commercial vendors and were used either as re-
ceived or dried prior to use as needed.
Compounds a-v were synthesized according to an
efficient route based on the click reaction, as outlined
Fig. 2. Generic structure of the designed fluconazole ana-
logues
in Scheme 1. After the key intermediate
ed by a reported procedure, compound
by ring-open reaction of oxirane with alkyne pro-
cleft were also found to be important (Fischer et al., pylamine. Synthesis of all the target triazole antifun-
1991; Hope et al., 2007). gal derivatives was achieved using the Cu (I)-
Based on the above-discussed results and new dis- catalyzed Sharpless click chemistry (Zhang et al.,
coveries (Ji et al., 2000), we have designed a series of 2006) approach from propargylated intermediate
4
was prepar-
5
was obtained
4
a-v
5
novel azoles (Fig. 2) as fluconazole analogues that con- and substituted azidomethyl benzene. The addition of
tain a triazole ring, a difluorophenyl group, a hydroxyl Cu (I) catalyst strongly activates terminal acetylenes
group, and a side chain with another triazole group. toward 1,3-dipole in organic azides, exclusively form-
While those compounds contain all the essential phar- ing the 1,4-disubstituted regioisomer.
macophores, the introduction of an additional triazole
group was expected to enhance the interaction between
those molecules and CYP51 to potentially result in
systemic antifungal compounds that are less likely to
develop drug resistance. Moreover, we systematically
Synthesis of 1-(1H-1,2,4-triazole-1-yl)-2-(2,4-dif-
luorophenyl)-3-alkyne propylamine-2-propanol
(5)
A mixture of compound
4 (33.3 g, 0.10 mol),
altered the side chain structure, which is oriented to CH3CH2OH (500 mL), and Et3N (50 mL), alkyne pro-
Scheme 1. Synthesis of the target compounds a-v
. Conditions: (a) ClCH2COCl, AlCl3, 50oC, 5 h, 80%; (b) 1H-1,2,4-triazole,
NaHCO3, toluene, reflux, 5 h, 42%; (c) (CH3)3SOI, NaOH, centylmethylammonium bromide, toluene, 60oC, 3 h, 53%; (d)
CH3SO3H, 0oC, 1 h, 89%; (e) Et3N, alkyne propylamine, EtOH, reflux, 6 h, 81.5%; (f) NaN3, substituted alkyne propylamine,
DMSO/H2O, CuSO4·5H2O, sodium ascorbate, rt, 12 h, 75-88%

Novel Triazole Derivatives as Antifungal Agents
1651
pylamine (8.3 g, 0.15 mol) was stirred and refluxed for 3.53 (1H, d,
J = 14.2 Hz, triazole-CH2-), 3.41 (1H, d, J
6 h. The reaction was monitored by thin liquid chro- = 14.2 Hz, triazole-CH2-), 2.83 (1H, d, J = 13.8 Hz,
matography (TLC). After filtration, the filtrate was CH2), 2.75 (1H, d, J = 13.8 Hz, CH2); 13C-NMR (75
evaporated under reduced pressure. Water was added MHz, CDCl3):
δ 161.52, 160.91, 151.52, 148.23, 143.38,
to the residue, extracted with ethylacetate twice, com- 137.74, 134.64, 131.17, 129.50, 129.21, 129.24, 128.46,
bined with the organic layer, washed with saturated 128.42, 125.78, 110.08, 102.26, 64.10, 62.29, 59.52,
NaCl solution twice, dried over anhydrous Na2SO4, 58.34, 50.13; LC-MS m/z: 444.3 (M+H)+; HRMS (m/
and evaporated to get compound
5
(23.8 g, 81.5%).
z): calcd. for C21H20F3N7O: 443.1681; found: 443.1695.
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
[(1-(4-fluorobenzyl)-1H-1,2,3-triazol-4-yl)methyl]
General procedure for the target compounds
(a-v)
A mixture of NaN3 (100 mg, 1.4 mmol), 2-fluorobenzyl amino}-2-propanol (c)
bromide (200 mg, 1.2 mmol), and DMSO (15 mL) was IR (KBr): 3353, 3281, 3078, 1637, 1559, 1164, 835; 1H-
stirred at room temperature for 6 h. Next, we added NMR (300 MHz, CDCl3):
the compound (175 mg, 0.6 mmol), sodium ascorbate (1H, s, triazole-H), 7.67 (1H, s, triazole-H), 6.71-7.44
(20 mg), CuSO4 5H2O (25 mg), and H2O (1 mL) and (7H, m, Ar-H), 5.48 (2H, s, Ar-CH2-), 4.46 (1H, d, = 14.4
stirred the mixture at room temperature for 2 h, then Hz, triazole-CH2-), 4.43 (1H, d, = 14.4 Hz, triazole-
put the reaction solution into NH3 H2O, extracted CH2-), 3.53 (1H, d, J = 14.1 Hz, triazole-CH2-), 3.42 (1H,
with ethylacetate. Following that, the organic layer d, = 14.1 Hz, triazole-CH2-), 2.87 (1H, d, = 13.8 Hz,
was acidificated with dilute hydrochloric acid, then CH2), 2.69 (1H, d,
= 13.8 Hz, CH2); 13C-NMR (75 MHz,
the aqueous layer was adjusted to a pH of about 7 by CDCl3): 163.38, 160.76, 152.51, 148.61, 143.22, 137.64,
δ 8.07 (1H, s, triazole-H), 7.87
5
·
J
J
·
J
J
J
δ
saturation sodium bicarbonate, extracted with ethyl- 134.64, 131.17, 129.61, 129.44, 129.23, 128.56, 128.52,
acetate, washed with water, and dried with Na2SO4 124.78, 110.45, 101.26, 64.10, 62.38, 59.52, 57.34, 51.11;
concentrated in a vacuum to afford compound
mg, 68%).
a
(181 LC-MS m/z: 444.2 (M+H)+; HRMS (m/z): calcd. for
C21H20F3N7O: 443.1681; found: 443.1703.
The target compounds b-v were synthesized by
same procedure as compound a.
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
[(1-(2-chlorobenzyl)-1H-1,2,3-triazol-4-yl)methyl]
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N- amino}-2-propanol (d)
[(1-(2-fluorobenzyl)-1H-1,2,3-triazol-4-yl) methyl] IR (KBr): 3363, 3273, 3079, 1643, 1567, 1176, 744; 1H-
amino}-2-propanol (a)
IR (KBr): 3350, 3284, 3080, 1635, 1550, 1173, 785; 1H- (1H, s, triazole-H), 7.63 (1H, s, triazole-H), 6.71-7.46 (7H,
NMR (300 MHz, CDCl3): 8.06 (1H, s, triazole-H), 7.87 m, Ar-H), 5.56 (2H, s, Ar-CH2-), 4.45 (1H, d, = 14.4 Hz,
(1H, s, triazole-H), 7.58 (1H, s, triazole-H), 6.70-7.36 triazole-CH2-), 4.32 (1H, d, = 14.4 Hz, triazole-CH2-),
(7H, m, Ar-H), 5.54 (2H, s, Ar-CH2-), 4.51 (1H, d, = 14.2 3.54 (1H, d, = 14.1 Hz, triazole-CH2-), 3.41 (1H, d,
Hz, triazole-CH2-), 4.41 (1H, d, J = 14.2 Hz, triazole- = 14.1 Hz, triazole-CH2-), 2.84 (1H, d, = 13.8 Hz,
CH2-), 3.63 (1H, d, = 14.3 Hz, triazole-CH2-), 3.47 (1H, CH2), 2.75 (1H, d,
= 13.8 Hz, CH2); 13C-NMR (75
d, = 14.3 Hz, triazole-CH2-), 2.73 (1H, d, = 13.9 Hz, MHz, CDCl3): 162.42, 160.73, 151.32, 147.23, 143.46,
CH2), 2.65 (1H, d,
= 13.9 Hz, CH2); 13C-NMR (75 137.69, 134.74, 132.17, 129.56, 129.36, 129.21, 128.46,
MHz, CDCl3):
NMR (300 MHz, CDCl3): δ 8.11 (1H, s, triazole-H), 7.76
δ
J
J
J
J
J
J
J
J
J
J
δ
J
δ
161.67, 160.33, 153.52, 148.63, 143.13, 128.32, 125.49, 111.08, 102.26, 64.11, 62.37, 59.42,
137.68, 133.64, 131.11, 129.35, 128.96, 128.74, 128.46, 58.56, 51.12; LC-MS m/z: 460.1 (M+H)+; HRMS (m/z):
127.42, 124.78, 110.65, 102.47, 65.10, 62.38, 59.51, calcd. for C21H20ClF2N7O: 459.1386; found: 459.1399.
58.74, 51.54; LC-MS m/z: 444.1 (M+H)+; HRMS (m/
z): calcd. for C21H20F3N7O: 443.1681; found: 443.1697.
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
[(1-(3-chlorobenzyl)-1H-1,2,3-triazol-4-yl)methyl]
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N- amino}-2-propanol (e)
[(1-(3-fluorobenzyl)-1H-1,2,3-triazol-4-yl)methyl]
amino}-2-propanol (b)
IR (KBr): 3357, 3248, 3047, 1629, 1565, 1169, 786; 1H-
NMR (300 MHz, CDCl3): 8.07 (1H, s, triazole-H), 7.68
δ
IR (KBr): 3351, 3274, 3082, 1638, 1557, 1174, 783; 1H- (1H, s, triazole-H), 7.54 (1H, s, triazole-H), 6.77-7.41
NMR (300 MHz, CDCl3):
(1H, s, triazole-H), 7.68 (1H, s, triazole-H), 6.72-7.38 (7H, Hz, triazole-CH2-), 4.31 (1H, d,
m, Ar-H), 5.57 (2H, s, Ar-CH2-), 4.47 (1H, d, J = 14.4 Hz, CH2-), 3.54 (1H, d, = 13.7 Hz, triazole-CH2-), 3.41 (1H,
triazole-CH2-), 4.43 (1H, d, J = 14.4 Hz, triazole-CH2-), d, = 13.7 Hz, triazole-CH2-), 2.76 (1H, d, = 13.8 Hz,
δ
8.09 (1H, s, triazole-H), 7.77 (7H, m, Ar-H), 5.76 (2H, s, Ar-CH2-), 4.48 (1H, d, J = 14.4
J
= 14.4 Hz, triazole-
J
J
J

1652
Y. Yan et al.
CH2), 2.73 (1H, d,
J
= 13.8 Hz, CH2); 13C-NMR (75 CH2), 2.64 (1H, d,
J
= 13.9 Hz, CH2); 13C-NMR (75
MHz, CDCl3): δ 162.57, 161.43, 154.32, 147.38, 143.47, MHz, CDCl3): δ 161.67, 160.32, 153.52, 148.65, 143.13,
137.76, 134.54, 132.16, 129.56, 129.28, 129.19, 128.56, 137.58, 133.64, 131.21, 129.35, 128.96, 128.76, 128.46,
127.32, 125.46, 111.48, 102.17, 64.12, 62.37, 59.36, 127.42, 124.76, 111.65, 102.47, 65.10, 62.37, 59.51,
58.57, 53.14; LC-MS m/z: 460.1 (M+H)+; HRMS (m/z): 58.74, 51.53; LC-MS m/z: 504.1 (M+H)+; HRMS (m/z):
calcd. for C21H20ClF2N7O: 459.1386; found: 459.1402.
calcd. for C21H20BrF2N7O: 503.0881; found: 503.0898.
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N- 1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
[(1-(4-chlorobenzyl)-1H-1,2,3-triazol-4-yl)methyl] [(1-(4-bromobenzyl)-1H-1,2,3-triazol-4-yl)methyl]
amino}-2-propanol (f)
IR (KBr): 3352, 3274, 3082, 1638, 1558, 1174, 843; 1H- IR (KBr): 3361, 3262, 3076, 1643, 1561, 1176, 839; 1H-
NMR (300 MHz, CDCl3): 8.09 (1H, s, triazole-H), NMR (300 MHz, CDCl3): 8.14 (1H, s, triazole-H),
amino}-2-propanol (i)
δ
δ
7.97 (1H, s, triazole-H), 7.68 (1H, s, triazole-H), 6.72- 7.86 (1H, s, triazole-H), 7.61 (1H, s, triazole-H), 6.71-
7.38 (7H, m, Ar-H), 5.57 (2H, s, Ar-CH2-), 4.47 (1H, d, 7.41 (7H, m, Ar-H), 5.56 (2H, s, Ar-CH2-), 4.47 (1H, d,
J
= 14.4 Hz, triazole-CH2-), 4.43 (1H, d,
triazole-CH2-), 3.54 (1H, d, = 14.2 Hz, triazole-CH2-), triazole-CH2-), 3.54 (1H, d,
3.41 (1H, d, = 14.2 Hz, triazole-CH2-), 2.83 (1H, d, 3.41 (1H, d, = 14.1 Hz, triazole-CH2-), 2.83 (1H, d,
= 13.8 Hz, CH2), 2.75 (1H, d,
= 13.8 Hz, CH2); 13C- 13.8 Hz, CH2), 2.75 (1H, d, = 13.8 Hz, CH2); 13C-
NMR (75 MHz, CDCl3): 161.52, 160.91, 151.52, NMR (75 MHz, CDCl3): 162.37, 160.71, 151.32,
J
= 14.4 Hz,
J
= 14.4 Hz, triazole-CH2-), 4.32 (1H, d,
J = 14.4 Hz,
J
J
= 14.1 Hz, triazole-CH2-),
J
J
J
J =
J
J
δ
δ
149.23, 143.38, 137.74, 134.64, 131.17, 129.50, 129.21, 147.23, 143.46, 136.69, 134.71, 132.17, 129.56, 129.46,
129.37, 128.46, 128.42, 125.78, 110.08, 102.26, 64.10, 129.21, 128.36, 128.12, 125.49, 111.17, 102.26, 64.11,
62.29, 59.52, 58.54, 50.13; LC-MS m/z: 460.3 (M+H)+; 62.38, 59.42, 58.56, 52.14; LC-MS m/z: 504.5 (M+H)+;
HRMS (m/z): calcd. for C21H20ClF2N7O: 459.1386; HRMS (m/z): calcd. for C21H20BrF2N7O: 503.0881;
found: 459.1403.
found: 503.0897.
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N- 1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
[(1-(2-bromobenzyl)-1H-1,2,3-triazol-4-yl)methyl] [(1-(2-methylbenzyl)-1H-1,2,3-triazol-4-yl)methyl]
amino}-2-propanol (g)
IR (KBr): 3373, 3268, 3071, 1643, 1567, 1175, 741; 1H- IR (KBr): 3374, 3257, 3074, 1652, 1568, 1176, 741; 1H-
NMR (300 MHz, CDCl3): 8.13 (1H, s, triazole-H), NMR (300 MHz, CDCl3): 8.15 (1H, s, triazole-H),
amino}-2-propanol (j)
δ
δ
7.76 (1H, s, triazole-H), 7.61 (1H, s, triazole-H), 6.73- 7.73 (1H, s, triazole-H), 7.61 (1H, s, triazole-H), 6.71-
7.46 (7H, m, Ar-H), 5.54 (2H, s, Ar-CH2-), 4.45 (1H, d, 7.46 (7H, m, Ar-H), 5.54 (2H, s, Ar-CH2-), 4.46 (1H, d,
J
= 14.4 Hz, triazole-CH2-), 4.32 (1H, d,
triazole-CH2-), 3.44 (1H, d, = 14.1 Hz, triazole-CH2-), triazole-CH2-), 3.44 (1H, d,
3.41 (1H, d, = 14.1 Hz, triazole-CH2-), 2.84 (1H, d, 3.37 (1H, d, = 14.1 Hz, triazole-CH2-), 2.84 (1H, d,
= 13.8 Hz, CH2), 2.75 (1H, d, = 13.8 Hz, CH2), 2.37 (3H,
= 13.8 Hz, CH2); 13C- 13.8 Hz, CH2), 2.75 (1H, d,
NMR (75 MHz, CDCl3): 163.41, 161.71,
162.42, 160.71, 151.32, s, CH3); 13C-NMR (75 MHz, CDCl3):
J
= 14.4 Hz,
J
= 14.4 Hz, triazole-CH2-), 4.31 (1H, d,
J = 14.4 Hz,
J
J
= 14.1 Hz, triazole-CH2-),
J
J
J
J =
J
J
δ
δ
147.23, 144.46, 137.69, 134.71, 132.16, 129.56, 129.36, 151.48, 147.21, 144.45, 137.79, 135.71, 132.16, 129.57,
129.22, 128.46, 128.37, 125.49, 111.18, 102.26, 64.11, 129.36, 129.02, 128.46, 128.36, 125.49, 111.17, 103.26,
62.36, 59.42, 58.56, 52.12; LC-MS m/z: 504.4 (M+H)+; 64.15, 62.34, 59.42, 58.57, 52.22, 20.93; LC-MS m/z
:
HRMS (m/z): calcd. for C21H20BrF2N7O: 503.0881; 440.2 (M+H)+; HRMS (m/z): calcd. for C22H23F2N7O:
found: 503.0895. 439.1932; found: 439.1951.
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N- 1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
[(1-(3-bromobenzyl)-1H-1,2,3-triazol-4-yl)methyl] [(1-(3-methylbenzyl)-1H-1,2,3-triazol-4-yl)methyl]
amino}-2-propanol (h)
IR (KBr): 3351, 3283, 3082, 1636, 1550, 1163, 786; 1H- IR (KBr): 3374, 3268, 3071, 1642, 1567, 1185, 776; 1H-
NMR (300 MHz, CDCl3): 8.16 (1H, s, triazole-H), 7.87 NMR (300 MHz, CDCl3): 8.03 (1H, s, triazole-H),
(1H, s, triazole-H), 7.58 (1H, s, triazole-H), 6.70-7.46 (7H, 7.76 (1H, s, triazole-H), 7.61 (1H, s, triazole-H), 6.73-
m, Ar-H), 5.54 (2H, s, Ar-CH2-), 4.51 (1H, d, = 14.2 Hz, 7.56 (7H, m, Ar-H), 5.54 (2H, s, Ar-CH2-), 4.45 (1H, d,
triazole-CH2-), 4.41 (1H, d, = 14.2 Hz, triazole-CH2-), J = 14.4 Hz, triazole-CH2-), 4.32 (1H, d, J = 14.4 Hz,
3.62 (1H, d, = 14.3 Hz, triazole-CH2-), 3.47 (1H, d, triazole-CH2-), 3.43 (1H, d, = 14.1 Hz, triazole-CH2-),
= 14.3 Hz, triazole-CH2-), 2.73 (1H, d, = 13.9 Hz, 3.40 (1H, d, = 14.1Hz, triazole-CH2-), 2.84 (1H, d, J =
amino}-2-propanol (k)
δ
δ
J
J
J
J
J
J
J

Novel Triazole Derivatives as Antifungal Agents
1653
13.8 Hz, CH2), 2.75 (1H, d,
J
= 13.8 Hz, CH2), 2.35 (3H, 3.41 (1H, d,
J
= 13.7 Hz, triazole-CH2-), 2.78 (1H, d,
J
s, CH3); 13C-NMR (75 MHz, CDCl3):
δ
162.41, 160.71, = 13.8 Hz, CH2), 2.73 (1H, d,
J
= 13.8 Hz, CH2); 13C-
151.32, 147.23, 144.56, 137.69, 134.71, 132.16, 129.57, NMR (75 MHz, CDCl3):
129.36, 129.32, 128.46, 128.37, 125.49, 111.28, 102.26, 147.48, 143.47, 137.76, 134.55, 132.16, 129.57, 129.28,
64.13, 62.36, 59.42, 58.56, 52.12, 21.92; LC-MS m/z 129.18, 128.52, 127.31, 125.46, 111.48, 102.27, 64.12,
440.7 (M+H)+; HRMS (m/z): calcd. for C22H23F2N7O: 62.47, 59.31, 58.57, 53.13; LC-MS m/z: 471.1 (M+H)+;
δ 162.58, 161.43, 154.32,
:
439.1932; found: 439.1955.
HRMS (m/z): calcd. for C21H20F2N8O3: 470.1626; found:
470.1641.
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
[(1-(4-methylbenzyl)-1H-1,2,3-triazol-4-yl)methyl] 1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
amino}-2-propanol (l) [(1-(4-nitrobenzyl)-1H-1,2,3-triazol-4-yl)methyl]
IR (KBr): 3374, 3268, 3071, 1653, 1567, 1175, 832; 1H- amino}-2-propanol (o)
NMR (300 MHz, CDCl3):
8.13 (1H, s, triazole-H), IR (KBr): 3351, 3284, 3087, 1637, 1556, 1174, 847; 1H-
7.75 (1H, s, triazole-H), 7.61 (1H, s, triazole-H), 6.73- NMR (300 MHz, CDCl3): 8.02 (1H, s, triazole-H),
7.46 (7H, m, Ar-H), 5.53 (2H, s, Ar-CH2-), 4.45 (1H, d, 7.77 (1H, s, triazole-H), 7.58 (1H, s, triazole-H), 6.71-
= 14.4 Hz, triazole-CH2-), 4.32 (1H, d, = 14.4 Hz, 7.38 (7H, m, Ar-H), 5.57 (2H, s, Ar-CH2-), 4.46 (1H, d,
triazole-CH2-), 3.54 (1H, d, = 14.1 Hz, triazole-CH2-), = 14.4 Hz, triazole-CH2-), 4.43 (1H, d, = 14.4 Hz,
3.41 (1H, d, = 14.1 Hz, triazole-CH2-), 2.84 (1H, d, J = triazole-CH2-), 3.53 (1H, d, = 14.2 Hz, triazole-CH2-),
13.8 Hz, CH2), 2.75 (1H, d, = 13.8 Hz, CH2), 2.33 (3H, 3.41 (1H, d, = 14.2 Hz, triazole-CH2-), 2.81 (1H, d,
s, CH3); 13C-NMR (75 MHz, CDCl3): 161.42, 160.77, = 13.8 Hz, CH2), 2.74 (1H, d, J = 13.8 Hz, CH2); 13C-
151.32, 147.13, 144.46, 137.69, 134.75, 132.16, 129.56, NMR (75 MHz, CDCl3): 163.51, 160.78, 151.52,
129.46, 129.22, 128.46, 128.38, 125.49, 111.38, 102.26, 149.24, 143.38, 138.74, 134.64, 131.29, 129.51, 129.26,
64.12, 62.36, 59.42, 58.56, 52.32, 20.62; LC-MS m/z 129.17, 128.46, 128.32, 125.71, 110.48, 102.21, 64.10,
δ
δ
J
J
J
J
J
J
J
J
J
J
δ
δ
:
440.4 (M+H)+; HRMS (m/z): calcd. for C22H23F2N7O: 62.29, 58.52, 58.54, 51.14; LC-MS m/z: 471.4 (M +
439.1932; found: 439.1948.
H)+; HRMS (m/z): calcd. for C21H20F2N8O3: 470.1626;
found: 470.1645.
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
[(1-(2-nitrobenzyl)-1H-1,2,3-triazol-4-yl)methyl]
amino}-2-propanol (m)
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
[(1-(2-cyanobenzyl)-1H-1,2,3-triazol-4-yl)methyl]
IR (KBr): 3351, 3274, 3080, 1633, 1551, 1159, 784; 1H- amino}-2-propanol (p)
NMR (300 MHz, CDCl3):
7.87 (1H, s, triazole-H), 7.58 (1H, s, triazole-H), 6.70- NMR (300 MHz, CDCl3):
7.26 (7H, m, Ar-H), 5.54 (2H, s, Ar-CH2-), 4.53 (1H, d, 7.75 (1H, s, triazole-H), 7.61 (1H, s, triazole-H), 6.71-
J = 14.2 Hz, triazole-CH2-), 4.41 (1H, d, = 14.2 Hz, 7.46 (7H, m, Ar-H), 5.54 (2H, s, Ar-CH2-), 4.46 (1H, d,
triazole-CH2-), 3.61 (1H, d, = 14.3 Hz, triazole-CH2-), = 14.4 Hz, triazole-CH2-), 4.32 (1H, d, = 14.4 Hz,
3.47 (1H, d, = 14.3 Hz, triazole-CH2-), 2.73 (1H, d, triazole-CH2-), 3.42 (1H, d, = 14.1 Hz, triazole-CH2-),
13.9 Hz, CH2), 2.65 (1H, d, J = 13.9 Hz, CH2); 13C- 3.41 (1H, d,
= 14.1 Hz, triazole-CH2-), 2.84 (1H, d,
NMR (75 MHz, CDCl3): 161.77, 160.43, 153.52, 13.8 Hz, CH2), 2.75 (1H, d,
= 13.8 Hz, CH2); 13C-
148.63, 142.13, 137.68, 133.64, 131.36, 129.35, 128.97, NMR (75 MHz, CDCl3): 162.41, 160.71, 151.32,
δ
8.16 (1H, s, triazole-H), IR (KBr): 3374, 3278, 3072, 1637, 1576, 1173, 744; 1H-
8.12 (1H, s, triazole-H),
δ
J
J
J
J
J
J
J
=
J
J
δ
=
J
δ
128.74, 128.41, 127.42, 124.78, 110.45, 102.42, 65.10, 147.53, 144.46, 137.61, 134.71, 132.16, 129.56, 129.35,
62.37, 59.51, 58.72, 53.54; LC-MS m/z: 471.5 (M+H)+; 129.22, 128.46, 128.31, 125.47, 111.18, 101.26, 64.11,
HRMS (m/z): calcd. for C21H20F2N8O3: 470.1626; found: 62.36, 59.42, 58.53, 52.15; LC-MS m/z: 451.1 (M+H)+;
470.1641.
HRMS (m/z): calcd. for C22H20F2N8O: 450.1728; found:
450.1745.
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
[(1-(3-nitrobenzyl)-1H-1,2,3-triazol-4-yl)methyl] 1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
amino}-2-propanol (n) [(1-(3-cyanobenzyl)-1H-1,2,3-triazol-4-yl)methyl]
IR (KBr): 3359, 3248, 3057, 1628, 1565, 1167, 785; 1H- amino}-2-propanol (q)
NMR (300 MHz, CDCl3):
8.17 (1H, s, triazole-H), IR (KBr): 3356, 3247, 3049, 1626, 1564, 1169, 785; 1H-
7.69 (1H, s, triazole-H), 7.54 (1H, s, triazole-H), 6.77- NMR (300 MHz, CDCl3): 8.17 (1H, s, triazole-H),
7.46 (7H, m, Ar-H), 5.76 (2H, s, Ar-CH2-), 4.38 (1H, d, 7.68 (1H, s, triazole-H), 7.54 (1H, s, triazole-H), 6.76-
= 14.4 Hz, triazole-CH2-), 4.21 (1H, d, = 14.4 Hz, 7.41 (7H, m, Ar-H), 5.76 (2H, s, Ar-CH2-), 4.47 (1H, d,
triazole-CH2-), 3.54 (1H, d, = 13.7 Hz, triazole-CH2-), = 14.4 Hz, triazole-CH2-), 4.31 (1H, d, = 14.4 Hz,
δ
δ
J
J
J
J
J

1654
Y. Yan et al.
triazole-CH2-), 3.55 (1H, d,
J
= 13.7 Hz, triazole-CH2-), triazole-CH2-), 3.73 (3H, s, -OCH3), 3.54 (1H, d,
Hz, triazole-CH2-), 3.41 (1H, d, = 14.1 Hz, triazole-
= 13.8 Hz, CH2); 13C- CH2-), 2.83 (1H, d,
= 13.8 Hz, CH2), 2.75 (1H, d,
162.58, 161.53, 154.32, 13.8 Hz, CH2); 13C-NMR (75 MHz, CDCl3):
162.48,
J = 14.1
3.41 (1H, d,
= 13.8 Hz, CH2), 2.72 (1H, d,
NMR (75 MHz, CDCl3):
J
= 13.7 Hz, triazole-CH2-), 2.76 (1H, d,
J
J
J
J
J =
δ
δ
147.38, 143.57, 137.76, 134.58, 132.16, 129.56, 129.38, 160.72, 151.32, 147.27, 143.46, 136.69, 134.71, 132.15,
129.19, 128.54, 127.31, 125.46, 111.48, 102.17, 64.12, 129.56, 129.43, 129.21, 128.37, 128.12, 125.49, 111.17,
62.39, 59.36, 58.57, 52.17; LC-MS m/z: 451.3 (M+H)+; 101.26, 64.11, 62.35, 59.42, 58.46, 56.3, 52.13; LC-MS m/
HRMS (m/z): calcd. for C22H20F2N8O: 450.1728; found:
z
: 456.7 (M+H)+; HRMS (m/z): calcd. for C22H23F2N7O2:
450.1742.
455.1881; found: 455.1898.
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N- 1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
[(1-(4-cyanobenzyl)-1H-1,2,3-triazol-4-yl)methyl]
amino}-2-propanol (r)
[(1-(2,6-dichlorobenzyl)-1H-1,2,3-triazol-4-yl)meth-
yl] amino}-2-propanol (u)
IR (KBr): 3352, 3287, 3078, 1647, 1559, 1164, 833; 1H- IR (KBr): 3358, 3263, 3075, 1641, 1562, 1178, 876, 834;
NMR (300 MHz, CDCl3):
δ δ 8.15 (1H, s, triazole-H),
8.06 (1H, s, triazole-H), 1H-NMR (300 MHz, CDCl3):
7.87 (1H, s, triazole-H), 7.67 (1H, s, triazole-H), 6.71- 7.83 (1H, s, triazole-H), 7.61 (1H, s, triazole-H), 6.73-
7.54 (7H, m, Ar-H), 5.48 (2H, s, Ar-CH2-), 4.46 (1H, d, 7.41 (6H, m, Ar-H), 5.56 (2H, s, Ar-CH2-), 4.45 (1H, d,
J
= 14.4 Hz, triazole-CH2-), 4.41 (1H, d,
triazole-CH2-), 3.53 (1H, d, = 14.1 Hz, triazole-CH2-), triazole-CH2-), 3.53 (1H, d,
3.42 (1H, d, = 14.1 Hz, triazole-CH2-), 2.86 (1H, d, 3.41 (1H, d, = 14.1 Hz, triazole-CH2-), 2.81 (1H, d,
= 13.8 Hz, CH2), 2.69 (1H, d,
= 13.8 Hz, CH2); 13C- = 13.8 Hz, CH2), 2.75 (1H, d, J = 13.8 Hz, CH2); 13C-
NMR (75 MHz, CDCl3): 162.31, 160.75, 152.51, NMR (75 MHz, CDCl3): 162.45, 161.71, 151.32,
J
= 14.4 Hz,
J
= 14.4 Hz, triazole-CH2-), 4.32 (1H, d,
J = 14.4 Hz,
J
J
= 14.1 Hz, triazole-CH2-),
J
J
J
J
J
δ
δ
148.62, 143.22, 137.64, 134.63, 131.17, 129.61, 129.44, 147.20, 143.46, 136.69, 134.01, 132.17, 129.56, 129.37,
129.21, 128.56, 128.52, 124.79, 110.45, 102.26, 64.10, 129.21, 128.36, 128.12, 125.48, 111.17, 101.26, 64.11,
62.37, 59.52, 57.34, 52.14; LC-MS m/z: 451.4 (M+H)+; 62.36, 59.42, 58.47, 52.24; LC-MS m/z: 494.3 (M+H)+;
HRMS (m/z): calcd. for C22H20F2N8O: 450.1728; HRMS (m/z): calcd. for C21H19Cl2F2N7O: 493.0996;
found: 450.1743.
found: 493.1011.
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N- 1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N-
[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amino}-2-
propanol (s)
[(1-(4-tertbutylbenzyl)-1H-1,2,3-triazol-4-yl)meth-
yl] amino}-2-propanol (v)
IR (KBr): 3361, 3262, 3076, 1643, 1561, 1176; 1H-NMR IR (KBr): 3352, 3284, 3086, 1637, 1556, 1175, 845; 1H-
(300 MHz, CDCl3):
s, triazole-H), 7.56 (1H, s, triazole-H), 6.74-7.31 (8H, 7.83 (1H, s, triazole-H), 7.58 (1H, s, triazole-H), 6.72-
m, Ar-H), 5.53 (2H, s, Ar-CH2-), 4.45 (1H, d, = 13.9 7.38 (7H, m, Ar-H), 5.57 (2H, s, Ar-CH2-), 4.47 (1H, d,
Hz, triazole-CH2-), 4.31 (1H, d, = 13.9 Hz, triazole- = 14.4 Hz, triazole-CH2-), 4.43 (1H, d, = 14.4 Hz,
CH2-), 3.54 (1H, d, = 14.1 Hz, triazole-CH2-), 3.45 (1H, triazole-CH2-), 3.53 (1H, d, = 14.2 Hz, triazole-CH2-),
d, = 14.1 Hz, triazole-CH2-), 2.83 (1H, d, J = 13.8 Hz, 3.41 (1H, d, = 14.2 Hz, triazole-CH2-), 2.82 (1H, d,
CH2), 2.75 (1H, d, = 13.8 Hz, CH2), 1.29-
= 13.8 Hz, CH2); 13C-NMR (75 = 13.8 Hz, CH2), 2.74 (1H, d,
MHz, CDCl3):
161.32, 160.57, 151.49, 147.21, 143.56, 1.33 (9H, m, 3-CH3); 13C-NMR (75 MHz, CDCl3):
δ 8.13 (1H, s, triazole-H), 7.81 (1H, NMR (300 MHz, CDCl3): δ 8.12 (1H, s, triazole-H),
J
J
J
J
J
J
J
J
J
J
J
δ
δ
136.61, 134.74, 132.38, 129.51, 129.38, 129.24, 128.36, 161.47, 160.59, 151.51, 149.24, 143.48, 138.74, 134.64,
127.12, 125.36, 110.17, 102.25, 64.12, 62.49, 59.41, 131.26, 129.51, 129.36, 129.17, 128.47, 128.32, 125.72,
58.57, 53.28; LC-MS m/z: 426.5 (M+H)+; HRMS (m/ 110.48, 102.24, 64.10, 62.29, 58.32, 58.54, 51.17,
z): calcd. for C21H21F2N7O: 425.1776; found: 425.1790.
34.83, 31.52, 31.56, 31.54; LC-MS m/z: 482.2 (M+H)+;
HRMS (m/z): calcd. for C25H29F2N7O: 481.2402; found:
1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-{N- 481.2425.
[(1-(4-Methoxybenzyl)-1H-1,2,3-triazol-4-yl)methyl]
amino}-2-propanol (t)
Antifungal activity
The in vitro antifungal activities of all target com-
IR (KBr): 3363, 3252, 3074, 1642, 1567, 1176, 837; 1H-
NMR (300 MHz, CDCl3):
7.86 (1H, s, triazole-H), 7.71 (1H, s, triazole-H), 6.72- fungi, Candida albicans SC5314 and Y0109, Crypto-
7.41 (7H, m, Ar-H), 5.56 (2H, s, Ar-CH2-), 4.37 (1H, d, coccus neoformans Candida parapsilosis Candida
= 14.4 Hz, triazole-CH2-), 4.31 (1H, d, = 14.4 Hz, tropicalis Trichophyton rubrum Candida kefyr, and
δ 8.14 (1H, s, triazole-H), pounds were evaluated against eight human pathogenic
J
,
,
J
,
,

Novel Triazole Derivatives as Antifungal Agents
1655
Aspergillus fumigatus, which are frequently encoun- serially diluted in growth medium, inoculated, and
tered in clinic. The results were compared with positive incubated at 35oC. Growth MIC was determined at 24
controls itraconazole, ketoconazole, voriconazole, and h for C. albicans and at 72 h for C. neoformans. The
fluconazole. C. albicans SC5314 and C. neoformans
,
results of assays are summarized in Table I. Those
purchased from ATCC (American type culture collec- data are the mean of two replicate tests performed
tion), were provided by Shanghai Changzheng Hospital; with each antifungal agent.
C. parapsilosis, C. albicans Y0109, C. tropicalis, T. ru-
brum C. kefyr, and A. fumigatus, which are clinic iso-
lates, were provided by Shanghai Changhai Hospital.
Fluconazole, itraconazole, ketoconazole, and voricon-
,
RESULTS
In our approach to synthesize title compounds, we
azole, which served as the positive controls, were ob- have performed the click reaction to connect the key
tained from their respective manufacturers. The in intermediate containing the terminal alkynyl and
5
vitro minimal inhibitory concentrations (MICs) of the the substituted azidomethyl benzene in the presence
title compounds were determined by the micro-broth of Cu (I)-catalyst in DMSO at room temperature to
dilution method in 96-well microtestplates according yield sufficient amounts of the title compounds.
to the methods defined by the National Committee for
Clinical Laboratory Standards (NCCLS, 2002). The antifungal activities of all the target compounds
MIC80 was defined as the first well with an approximate were active against nearly all fungi tested, except for
80% reduction in growth compared to the growth of A. fumigatus. Among the compounds tested,
the drug-free well. For assays, the title compounds to showed higher activity against C. albicans SC5314,
The results of Table I clearly show that the in vitro
a-v
b, c, e, i,
p
be tested were dissolved in dimethyl sulfoxide (DMSO), C. albicans Y0109, C. parapsilosis, and C. kefyr than
Table I. Antifungal activities of the target compounds in vitro
MICa (
µg/mL)
Compound
No.
C. alb SC5314 C. alb Y0109
C. neo
T. nru
C. tro
C. pra
C. kef
A. fum
a
b
c
d
e
f
g
h
i
j
k
l
m
n
o
p
q
r
s
t
u
v
ICZ
KCZ
VCZ
FCZ
0.0625
0.0625
0.0156
0.0625
0.0156
0.25
1
0.25
0.25
0.25
0.25
<0.125
<0.125
0.5
<0.125
2
1
0.5
<0.125
1
0.25
0.5
2
1
1
0.25
<0.125
1
1
1
1
1
0.0625
<0.125
<0.125
0.5
16
0.0156
1
16
0.25
4
16
16
4
4
1
0.25
4
0
4
16
4
4
16
4
4
4
4
16
1
0.25
16
16
4
4
4
0.0625
<0.125
<0.125
2
1
0.25
0.0625
0.0625
0.25
0.0625
0.25
1
1
0.25
1
0.25
0.0625
4
4
1
1
>64
>64
>64
>64
64
0.0625
0.0625
0.0156
0.0625
1
1
1
1
1
1
1
1
4
4
0.25
0.0625
4
1
1
16
4
<0.0625
<0.125
<0.125
<0.125
0.0625
0.0625
1
0.25
16
4
1
1
4
1
4
4
4
4
>64
>64
>64
>64
>64
>64
>64
>64
>64
>64
>64
>64
>64
32
16
32
32
2
0.125
<0.125
>64
4
1
0.0156
0.25
0.25
>64
>64
16
16
4
1
0.0156
0.0625
0.0625
1
0.0156
0.0625
0.00097
0.0156
<0.0625
<0.125
32
0.25
0.25
1
1
1
0.25
0.0156
1
1
1
1
16
16
16
16
1
0.125
0.5
<0.125
8
1
1
0.25
0.0625
<0.125
0.25
<0.125
0.25
0.0625
0.0625
0.0039
1
0.5
aMinimum inhibitory concentration for 80% inhibition of growth

1656
Y. Yan et al.
FCZ. Most of the target compounds exhibited higher Eleventh Five Year Military Medicine and Public
activities against C. albicans SC5314 than all four Health Research Projects (Nos. 06MB206), and Shang-
positive controls. In particular, the MIC values of com- hai Leading Academic Discipline Project Number:
pounds
of FCZ against C. albicans SC5314. The MIC values of
compounds , and were 40 times lower than
that of FCZ against C. albicans Y0109, and the MIC
value of compound was 64 times lower than that of
FCZ against C. kefyr.
From those results, we may state that differences
between the activities of the compounds were due to
different substituents such as F, Br, Cl, and CN over
the benzene ring. The substituted positions were also
very important for antifungal activity. The hydropho-
bic group is favorable at position 3 or position 4 of the
terminal phenyl group, possibly because of the addi-
tional hydrophobic interaction with CYP51.
c, e, k, s, and v were 32 times lower than that B906.
b,
c,
e,
i
q
REFERENCES
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Fridkin, S. K. and Jarvis, W. R., Epidemiology of nosocomial
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Lu, J., A three-dimensional model of lanosterol 14α-
DISCUSSION
In this work, we found the click reaction to be a facile
method to incorporate a hydrophobic substitution onto
the side chain of azole. We were able to place a phenyl
group onto the side chain of azole via the 1,2,3-tri-
azole. The resulting material suggests self-assembly
behavior in both water and DMSO. In addition to its
simplicity and mild reaction conditions, that method
provides a wide range of inserting 1,2,3-triazoles at
excellent yields with high regioselectivity in a single
step operation.
On the basis of the active site of CYP51, a series of
novel azoles with side chains including a 1,2,3-triazole
group and a substituted-phenyl group were designed
and synthesized. The side chains interacted with
CYP51 through hydrophobic and van der Waals reac-
tions. The in vitro antifungal activity assay indicated
that the new azoles show good activity against impor-
tant fungal pathogens. Interestingly, the compounds
were also active against an azole-resistant clinical
strain. The research has led to the discovery of a ser-
ies of compounds for further optimization.
demethylase of candida albicans and its interaction with
azole antifungals. J. Med. Chem., 43, 2493-2505 (2000).
Latgé, J. P., Aspergillus fumigatus and aspergillosis. Clin.
Microbiol. Rev., 12, 310-350 (1999).
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ACKNOWLEDGEMENTS
This work was supported by the National Natural
Science Foundation of China (Nos. 09dZ1976700),