Design, synthesis and structure-activity relationships of new triazole derivatives containing N-substituted phenoxypropylamino side chains

Article abstract of DOI:10.1016/j.ejmech.2012.04.013

The incidence of invasive fungal infections and resistance to antifungal agents is increasing dramatically. It is highly desirable to develop novel azoles with improved biological profiles. The structure-activity relationship (SAR) of the N-substitutions was investigated in this study. In vitro antifungal activities revealed that sterically large groups were not favored for the N-substitutions. The removal of the N-substitutions had little effect on the antifungal activity. Two compounds with free amine group (i.e. 9a and 10a) showed excellent activity with broad antifungal spectrum. The SAR results were supported by molecular docking and the N-substitutions were found to be important for the conformation of the side chains. The SAR and binding mode of the azoles are useful for further lead optimization.

Full text of DOI:10.1016/j.ejmech.2012.04.013

European Journal of Medicinal Chemistry 53 (2012) 292e299
Contents lists available at SciVerse ScienceDirect
European Journal of Medicinal Chemistry
journal homepage: http://www.elsevier.com/locate/ejmech
Original article
Design, synthesis and structureeactivity relationships of new triazole derivatives
containing N-substituted phenoxypropylamino side chains
Shengzheng Wang a 1, Gang Jin b 1, Wenya Wang a, Lingjian Zhu a, Yongqiang Zhang a, Guoqiang Dong a,
**
,
,
,
a,
*
Yang Liu a, Chunlin Zhuang a, Zhenyuan Miao a, Jianzhong Yao a, Wannian Zhang a , Chunquan Sheng
a Department of Medicinal Chemistry, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai 200433, People’s Republic of China
b Department of General Surgery, Changhai Hospital, Second Military Medical University, 168 Changhai Road, Shanghai 200433, People’s Republic of China
a r t i c l e i n f o
a b s t r a c t
Article history:
The incidence of invasive fungal infections and resistance to antifungal agents is increasing dramatically.
It is highly desirable to develop novel azoles with improved biological profiles. The structureeactivity
relationship (SAR) of the N-substitutions was investigated in this study. In vitro antifungal
activities revealed that sterically large groups were not favored for the N-substitutions. The removal of
the N-substitutions had little effect on the antifungal activity. Two compounds with free amine group (i.e.
9a and 10a) showed excellent activity with broad antifungal spectrum. The SAR results were supported
by molecular docking and the N-substitutions were found to be important for the conformation of the
side chains. The SAR and binding mode of the azoles are useful for further lead optimization.
Ó 2012 Elsevier Masson SAS. All rights reserved.
Received 3 November 2011
Received in revised form
7 April 2012
Accepted 10 April 2012
Available online 19 April 2012
Keywords:
Azole
Structureeactivity relationship
Molecular docking
Antifungal activity
1. Introduction
used as the first-line agent in treating Candida infections [4].
However, FLC is not effective against invasive aspergillosis and has
During the past two decades, the incidence of systemic fungal
infections has been increasing dramatically due to an increasing
number of immunocompromised hosts, such as patients under-
going organ transplants or anticancer chemotherapy and
patients with AIDS. However, there is a lack of effective anti-
fungal agents that can be used for life-threatening fungal
infections. Clinically available antifungal agents include
amphotericin B, 5-fluorocytosine, azoles (e.g. fluconazole and
itraconazole), and echinocandins (e.g. caspofungin and
micafungin).
suffered severe drug resistance [5,6]. In comparison with FLC,
itraconazole (ITR) has a broader antifungal spectrum and better
toleration but its variable oral absorption and low bioavailability
have hampered its clinical use. Several novel azole antifungal
agents, such as voriconazole [7], posaconazole [8], ravuconazole [9]
and albaconazole [10], are marketed or currently in the late stages
of clinical trials.
Nowadays, fungal resistance caused by the broad use of azoles is
becoming serious, which has significantly reduced the therapeutic
efficacy of them. The mechanism of drug resistance includes
mutation or abnormal expression of CYP51 [11,12], over expression
of drug excretion genes (e.g. CDR1, CDR2 and MDR1) [13], the
formation of biofilm changes [14], and so on. The severe resistance
has led to an ongoing search for new azoles [15e22].
In our previous studies, new azoles with substituted phenox-
ypropylamino side chain (Fig. 1) were designed and synthesized.
Most of them showed excellent in vitro antifungal activity with
broad spectrum, representing promising leads for further optimi-
zation [23e25]. In order to get more information of
structureeactivity relationships (SARs), the influence of N-substit-
uents on the antifungal activity was investigated in the present
study (Fig. 1). Their in vitro antifungal activity in combination with
binding modes obtained from molecular docking can provide useful
information for further optimization.
Azoles are currently the most widely used agents in antifungal
chemotherapy. They possess the antifungal activity by competitive
inhibition of lanosterol 14a
-demethylase (CYP51) [1]. Sterol d22
desaturase (CYP61), a cytochrome P450 enzyme involved in the last
step of ergosterol biosynthesis, has also been described as the
second target for the azole antifungals [2,3]. Fluconazole (FLC)
shows good antifungal activity and relatively low toxicity, which is
* Corresponding author. Tel./fax: þ86 21 81871239.
** Corresponding author. Tel./fax: þ86 21 81871243.
E-mail addresses: zhangwnk@hotmail.com (W. Zhang), shengcq@hotmail.com
(C. Sheng).
1
These two authors contributed equally to this work.
0223-5234/$ e see front matter Ó 2012 Elsevier Masson SAS. All rights reserved.
doi:10.1016/j.ejmech.2012.04.013

S. Wang et al. / European Journal of Medicinal Chemistry 53 (2012) 292e299
293
Fig. 1. Design rationale of the target compounds.
2. Chemistry
3. Results and discussion
The chemical synthesis of the target compounds was outlined in
Scheme 1. The oxirane intermediate 7 was synthesized by our
reported procedure [26]. The phenoxypropylamino side chains 6a,
b were synthesized via three steps. Excess 1,3-dibromopropane was
treated with phenols to give bromopropoxybenzene 4a, b. Then,
compounds 4a, b reacted with NaN3 in DMSO at room temperature
to afford azides 5a, b. The azide groups of compounds 5a, b were
reduced to amino groups in the presence of Ph3P and MeOH. After
treating with EtOAc saturated by hydrogen chloride, the side chains
6a, b were obtained. Ring-open reactions were performed between
compounds 6a, b and oxirane 7 to give intermediates 8a, b. In the
presence of KI and K2CO3, various halogen substituted reagents
were reacted with compounds 8a, b to afford the target compounds
9aem and 10ael. All the target compounds were obtained as
racemates.
3.1. In vitro antifungal activity
The in vitro antifungal activity is shown in Table 1. Six important
fungal pathogens were chosen for assaying. FLC and ITR were used
as positive controls. The synthesized compounds showed moderate
to excellent antifungal activity against the tested fungal pathogens.
Several compounds, such as 9a, 10a, 10b and 10k, showed better
antifungal activity than FLC. On the Candida albicans strain,
compounds 9a, 10a, and 10b displayed the highest activity with
their MIC80 in the range of 0.0313e0.0625
potent than FLC and ITR. In addition, compounds 9l, 10k and 10l
also showed comparable activity to FLC (MIC80 range: 0.25e0.5 g/
mg/mL, which was more
m
mL). Particularly, compounds 9a and 10a also displayed broad
spectrum. Their inhibitory activity toward Candida tropicalis and
Candida krusei (MIC80 < 0.125 mg/mL) was better than FLC and lead
Scheme 1. The synthetic route for target compounds 9ae10l. Reagents and conditions: a. phenol, K2CO3, EtOH, reflux, 4 h, 75e82%; b. Sodium azide, DMSO, rt, 88e91%; c. Ph3P,
MeOH, reflux; HCl, EtOAc, rt, 44e56%; d. EtOH, (Et)3N, reflux, 58e65%; e. K2CO3, KI, CH3CN, reflux, 9 h, 21e58%.

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S. Wang et al. / European Journal of Medicinal Chemistry 53 (2012) 292e299
Table 1
In vitro antifungal activity of the compounds (MIC80, m
g$mLꢀ1).a
Compounds
C. albicans
C. tropicalis
C. parapsilosis
C. neoformans
C. krusei
T. rubrum
9a
9b
0.0313
0.5
<0.125
1
0.5
2
1
1
<0.125
4
0.5
2
9c
9d
9e
9f
9g
9h
9i
9j
9k
2
2
2
4
4
2
4
4
2
4
8
8
8
4
16
16
>64
4
32
0.5
2
64
16
64
16
32
8
0.5
2
32
16
64
8
16
>64
>64
>64
64
8
4
4
4
4
4
8
8
4
32
4
8
16
4
64
16
8
16
64
8
8
8
2
1
4
8
16
16
32
2
8
64
1
4
2
16
64
32
8
32
64
4
8
16
1
1
1
4
16
4
8
16
8
>64
2
4
1
1
2
0.5
2
0.5
4
0.0625
0.0313
1
2
2
8
4
2
2
4
0.25
0.25
0.5
0.0125
0.5
0.125
1
8
8
2
8
4
9l
9m
10a
10b
10c
10d
10e
10f
10g
10h
10i
10j
10k
10l
1
<0.125
0.5
16
8
8
8
8
8
8
8
1
4
<0.125
1
1
1
8
4
8
4
4
8
1
1
2
0.5
4
1
2
1
2
FLC
ITR
<0.125
1
<0.125
0.125
1
4
1
1
0.125
a
Abbreviations: C. albicans, Candida albicans; C. tropicalis, Candida tropicalis; C. parapsilosis, Candida parapsilosis; C. neoformans, Cryptococcus neoformans; C. krusei, Candida
krusei; T. rubrum, Trichophyton rubrum; FLC, Fluconazole; ITR, Itraconazole.
compound 1, and comparable to that of ITR. In comparison with the
activity against C. albicans, most of the compounds showed
decreased inhibitory activity toward other Candida spp. The same
trend was also observed for the activity against Cryptococcus neo-
formans. However, the activity of compounds 9a, b, 10aec toward
Wu’s group reported that the introduction of N-allyl group and
N-propargyl group would interact with the surrounding hydro-
phobic residues and enhance the antifungal activity [27,28]. In the
present study, N-propargyl derivatives 9l and 10l showed good
antifungal activity on the C. albicans strain, but their antifungal
spectrum is relatively narrow. For N-allyl substituted compounds
9k and 10k, they only showed moderate antifungal activity. The
difference in the influence of N-substitutions on the antifungal
activity indicates that the same substitution might result in distinct
conformational changes for the different types of side chains. When
larger groups (e.g. benzyl and ester) were introduced, significant
decrease of the antifungal activity was observed for compounds
9eej and 10eej.
C. neoformans (MIC80 ¼ 1
mg/mL) was comparable to the lead
compounds (1 and 2) and superior to FLC. Moreover, all the
compounds were also active against Trichophyton rubrum and
compound 9a (MIC80 ¼ 0.5
mg/mL) showed better activity than
the lead compounds and FLC.
3.2. Structureeactivity relationships
In our previous studies, N-methyl group of the lead structure 2
could form hydrophobic interaction with the surrounding residues
and maintain the suitable conformation of the side chain in the
CYP51 active site [23e25]. The role of N-methyl side chains were
also confirmed by other reports [15,16]. Compounds 9a and 10a,
whose methyl group is replaced by hydrogen atom, showed better
antifungal activity than FLC with broad antifungal spectrum.
However, they were slightly less potent than lead compound 2 on
the C. albicans strain, indicating the introduction of the methyl
group could enhance the antifungal activity. On the contrary,
compounds 9a and 10a showed better activity against C. krusei than
the lead compounds, suggesting the difference between the CYP51
active sites of various fungal pathogens. When the N-methyl group
of the lead compounds was replaced by the ethyl group
(compounds 9b and 10b), the antifungal activity was decreased
slightly apart from C. albicans and T. rubrum. Compounds with
larger N-alkyl groups, such as propyl (compound 9c), butyl
(compound 9d), and isobutyl (compound 9m), showed significantly
decreased antifungal activity. It is inferred that larger substituents
might clash with the surrounding residues and disturb the side
chain’s suitable conformation in the CYP51 active site.
3.3. Binding mode of the azoles
Our group has constructed three-dimensional (3D) models of
CYP51 from C. albicans (CACYP51) using homology modeling
methods [29,30]. In this study, all the analogs were included in the
molecular docking to clarify their binding modes with CACYP51
and provide information for further optimization. As shown in
Table 2, compounds with smaller substituents such as 9a, 9b, 10a,
10b and 10l have relatively higher Fitness scores, which are
consistent with their antifungal activity. In contrast, weakly active
compounds such as 9f, 9j, 10f and 10g also have relatively lower
Fitness scores. The good correlation between antifungal activity and
docking score indicates that a suitable substituent has a great
impact on the antifungal activity. Fig. 2 shows the interaction
between compound 9a and the active site of CACYP51. The triazole
ring of compound 9a binds to the heme group through the
formation of a coordination bond with the iron atom. The difluor-
ophenyl group forms hydrophobic interactions with Phe126,
Met306, and Tyr132. The phenoxypropylamino side chain,
extended in the CYP51 channel, mainly forms hydrophobic and Van

S. Wang et al. / European Journal of Medicinal Chemistry 53 (2012) 292e299
295
Table 2
However, this hydrogen bond was lost for compound 9a, which
highlighted the importance of N-substitutions on the conformation
of the side chains.
GOLD docking scores of the compounds.a
Compounds
Fitness
S(hb_ext)
S(vdw_ext)
S(int)
9a
9b
9c
9d
9e
9f
9g
9h
9i
9j
73.05
72.24
64.79
63.65
63.01
56.48
55.02
61.62
62.56
33.91
71.71
71.42
59.53
68.95
71.63
63.14
62.96
58.46
49.87
49.9
10
10
10.12
10
10
8.99
10
9.64
9.46
0.12
10
8.56
10.12
10.01
10
50.51
53.4
ꢀ6.4
ꢀ11.19
ꢀ21.47
ꢀ17.96
ꢀ12.89
ꢀ18.67
ꢀ11.31
ꢀ17.08
ꢀ17.01
ꢀ23.01
ꢀ11.39
ꢀ8.76
4. Conclusion
55.37
52.08
47.93
48.11
40.97
50.23
50.99
41.31
53.16
52.09
52.33
46.81
52.38
50.37
53.87
45.58
45.94
42.98
51.05
54.8
With an aim to get more SAR information for the new antifungal
azoles with phenoxypropylamino side chains, the impact of N-
substitutions on the antifungal activity was investigated. The
in vitro antifungal activity assay indicates that the substituent has
a great influence on the antifungal activity. A suitable substituent
(e.g. the methyl group) could form hydrophobic interaction with
the surrounding residues such as Tyr118, Leu121, and Thr122, and
enhance the antifungal activity. A larger group is not tolerated at
this position because it might crash with the active site residues.
The removal of the N-substitution led to the slightly decrease of the
antifungal activity against C. albicans. Interestingly, such azoles
with free amine showed increased activity toward other Candida
spp. Molecular docking studies revealed that the N-substitutions
played an important role for the conformation of the side chain.
Among the synthesized compounds, 9a and 10a showed excellent
antifungal activity against all the tested pathogens, which are
promising leads for further study. The obtained SAR and binding
mode can provide useful information for lead optimization.
9k
9l
9m
10a
10b
10c
10d
10e
10f
10g
10h
10i
10j
10k
10l
1
ꢀ22.55
ꢀ5.43
ꢀ10.39
ꢀ16.12
ꢀ21.12
ꢀ14.44
ꢀ23.24
ꢀ19.2
10
10
10.22
9.95
10
4.01
0.24
1.5
10
10
10
10.05
60.84
62.64
26.26
73.76
68.19
74.38
70.55
ꢀ13.37
ꢀ12.95
ꢀ20.92
ꢀ10.65
ꢀ12.3
33.22
54.11
51.26
51.9
ꢀ6.98
2
49.01
ꢀ6.89
5. Experimental protocols
a
Abbreviations: Fitness, the negative of the sum of the component energy terms;
S(hb_ext), proteineligand hydrogen bond energy; S(vdw_ext), proteineligand van
der Waals (vdw) energy; S(int), the sum of ligand internal vdw energy and ligand
torsional strain energy.
5.1. Pharmacology
In vitro antifungal activity was measured by means of the serial
dilution method in 96-well microtest plates. Test fungal strains
were obtained from the American Type Culture Collection (ATCC) or
were clinical isolates. The determination of minimum inhibitory
concentration (MIC) was performed according to the recommen-
dations of National Committee for Clinical Laboratory Standards
(NCCLS) with RPMI 1640 (Sigma) buffered with 0.165MMOPS
(Sigma) as the test medium. The MIC80 value is defined as the
lowest concentration of test compound that results in a culture
with turbidity less than or equal to 80% inhibition relative to the
growth of the control. Test compounds were dissolved in DMSO
serially diluted in growth medium. The yeast strains were incu-
bated at 35 ꢁC, and the dermatophytes at 28 ꢁC. Growth MIC80 was
determined at 24 h for Candida spp., and at 72 h for C. neoformans.
der Waals interactions with the surrounding residues such as
Tyr118, Leu121, Phe233, Phe380, and Tyr505. The pocket around
the NH group (Tyr118, Leu121 and Thr122) is not large enough to
accommodate the large substitutions (e.g. benzyl). It is worth
noting that the oxygen atom in the side chain of lead compound 2
formed hydrogen-bonding interaction with Ser378 [23e25].
5.2. General procedure for the synthesis of compounds
All reagents and solvents were reagent grade or were purified by
standard methods before use. 1H and 13C NMR spectra were
recorded on a Bruker 500 spectrometer with TMS as an internal
standard and CDCl3 as solvent. Chemical shifts (d values) and
coupling constants (J values) are given in ppm and Hz, respectively.
ESI mass spectra were performed on an API-3000 LC-MS spec-
trometer. Elemental analyses were performed with a MOD-1106
instrument and were consistent with theoretical values within
ꢂ0.4%. TLC analysis was carried out on silica gel plates GF254
(Qindao Haiyang Chemical, China). Silica gel column chromatog-
raphy was performed with Silica gel 60G (Qindao Haiyang Chem-
ical, China). Anhydrous solvent and reagents were all analytical
pure and dried through routine protocols.
5.2.1. Chemical synthesis of 1-bromo-4-(3-bromopropoxy)benzene
(4a)
1,3-Dibromopropane (21.09 g, 0.10 mol) was added dropwise to
a stirred mixture of 4-bromophenol (8.65 g, 0.05 mol), K2CO3 (6.9 g,
0.05 mol) in 50 mL EtOH at 80 ꢁC for 4 h. The solvent was removed
Fig. 2. The docking conformation of compound 9a in the active site of CACYP51.
Important residues involved in the binding site are shown. Residues that form the
hydrophobic pocket near the nitrogen atom (Leu121, Thr122, and Tyr118) are colored
red. (For interpretation of the references to colour in this figure legend, the reader is
referred to the web version of this article.)

296
S. Wang et al. / European Journal of Medicinal Chemistry 53 (2012) 292e299
under reduced pressure, diluted with H2O (70 mL) and extracted by
EtOAc (80 mL ꢃ 3). The organic layer was separated, dried with
Na2SO4, and concentrated under reduced pressure. The residue was
purified by column chromatography (hexane) to give 4a as trans-
Anal. calcd. for C22H25BrF2N4O2: C, 53.34; H, 5.09; N,11.31. Found: C,
53.33; H, 5.10; N, 11.29. The synthetic method for the compounds
9cem and 10bel was similar to the synthesis of compound 9b.
parent oil: 12.05 g (82.0%). 1H NMR
d
: 6.79e7.40 (m, 4H, AreH), 4.08
5.2.6. 1-((3-(4-Bromophenoxy)propyl)(propyl)amino)-2-(2,4-difluoro-
phenyl)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol (9c)
(t, 2H, J ¼ 5.8 Hz, OCH2), 3.60 (t, 2H, J ¼ 6.5 Hz, CH2Br), 2.28e2.36
(m, 2H, CH2CH2CH2). ESI-MS: 294.49 [M þ 1]. The synthetic
method for the compound 4b was similar to the synthesis of
compound 4a.
Yellow oil: 0.09 g (43.6%). 1H NMR
d: 8.16 (s, 1H, TriazC3eH), 7.80
(s,1H, TriazC5eH), 6.69e7.59 (m, 7H, AreH), 4.56 (d,1H, J ¼ 14.4 Hz,
C1eHa), 4.44 (d, 1H, J ¼ 14.4 Hz, C1eHb), 3.78 (t, 2H, J ¼ 5.7 Hz,
OCH2), 3.13 (d, 1H, J ¼ 14.1 Hz, C3eHa), 2.77 (d, 1H, J ¼ 14.1 Hz,
C3eHb), 2.45 (t, 2H, J ¼ 7.2 Hz, NCH2CH2CH2O), 2.27 (t, 2H,
NCH2CH2CH3), 1.69 (m, 2H, NCH2CH2CH2O), 1.31 (m, 2H,
NCH2CH2CH3), 0.59 (t, 3H, NCH2CH2CH3). ESI-MS: 509.59 [M]. Anal.
calcd. for C23H27BrF2N4O2: C, 54.23; H, 5.34; N, 11.00. Found: C,
54.25; H, 5.33; N, 11.01.
5.2.2. Chemical synthesis of 1-(3-azidopropoxy)-4-bromobenzene
(5a)
NaN3 (0.42 g, 6.5 mmol) was added to a stirred solution of 1-
bromo-4-(3-bromopropoxy)benzene (1.47 g, 5 mmol) in DMSO
(25 mL). The mixture was stirred for 12 h at room temperature,
diluted with H2O (50 mL), and extracted by EtOAc (50 mL ꢃ 3). The
organic layer was separated, dried with Na2SO4, and concentrated
under reduced pressure. The residue was white solid and reacted to
the next step without further purification. The synthetic method
for the compound 5b was similar to the synthesis of compound 5a.
5.2.7. 1-((3-(4-Bromophenoxy)propyl)(butyl)amino)-2-(2,4-difluoro-
phenyl)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol (9d)
Brown solid: 0.11 g (42.8%). 1H NMR
d: 8.15 (s, 1H, TriazC3eH),
7.80 (s, 1H, TriazC5eH), 6.69e7.55 (m, 7H, AreH), 4.54 (d, 1H,
J ¼ 14.3 Hz, C1eHa), 4.42 (d, 1H, J ¼ 14.4 Hz, C1eHb), 3.78 (t, 2H,
J ¼ 5.7 Hz, OCH2), 3.13 (d, 1H, J ¼ 14.1 Hz, C3eHa), 2.77 (d, 1H,
J ¼ 14.1 Hz, C3eHb), 2.44 (t, 2H, J ¼ 7.5 Hz, NCH2CH2CH2O), 2.24 (t,
2H, NCH2CH2CH2CH3), 1.68 (m, 2H, NCH2CH2CH2O), 1.10e1.20 (m,
5.2.3. Chemical synthesis of 3-(4-bromophenoxy)propan-1-amine
hydrochloride (6a)
Ph3P (1.77 g, 6.75 mmol) was added to a stirred solution of 1-(3-
azidopropoxy)-4-bromobenzene in MeOH (30 mL). The mixture
was refluxed for 5 h, and concentrated under reduced pressure. The
residue was added 20 mL EtOAc saturated by hydrogen chloride.
After filtration, compound 6a was obtained as white solid powder
4H, NCH2CH2CH2CH3), 0.78 (t, 3H, NCH2CH2CH2CH3). 13C NMR
d:
163.67, 161.69, 159.89, 157.97, 157.81, 150.92, 144.80, 132.24, 129.47,
126.70, 116.13, 112.93, 111.36, 104.19, 71.47, 65.75, 59.14, 56.31,
54.84, 51.84, 28.93, 26.69, 20.22, 13.78. ESI-MS: 525.61 [M þ 2].
Anal. calcd. for C24H29BrF2N4O2: C, 55.07; H, 5.58; N, 10.70. Found:
C, 55.05; H, 5.57; N, 10.68.
(0.71 g). The total yield of two steps was 56%. 1H NMR
d: 6.90e7.48
(m, 4H, AreH), 4.05 (t, 2H, J ¼ 6.1 Hz, OCH2), 2.93 (t, 2H, J ¼ 6.9 Hz,
CH2NH2), 2.01 (m, 2H, CH2CH2CH2). ESI-MS: 232.33 [M þ 1]. The
synthetic method for the compound 6b was similar to the synthesis
of compound 6a.
5.2.8. 1-(Benzyl(3-(4-bromophenoxy)propyl)amino)-2-(2,4-difluoro-
phenyl)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol (9e)
Yellow oil: 0.12 g (57.8%). 1H NMR
d: 8.05 (s, 1H, TriazC3eH), 7.75
5.2.4. Chemical synthesis of 1-((3-(4-bromophenoxy)propyl)
amino)-2-(2,4-difluorophenyl)-3-(1H-1,2,4-triazol-1-yl)propan-2-
ol (9a)
(s, 1H, TriazC5eH), 6.64e7.59 (m,12H, AreH), 4.48 (d,1H, J ¼ 14.0 Hz,
C1eHa), 4.37 (d, 1H, J ¼ 14.0 Hz, C1eHb), 3.72 (t, 2H, J ¼ 5.6 Hz,
OCH2), 3.50 (d, 1H, J ¼ 13.4 Hz, NCH2Ar), 3.33 (d, 1H, J ¼ 13.4 Hz,
NCH2Ar), 3.19 (d, 1H, J ¼ 13.9 Hz, C3eHa), 2.86 (d, 1H, J ¼ 13.9 Hz,
C3eHb), 2.50 (t, 2H, J ¼ 7.1 Hz, NCH2CH2CH2O), 1.71 (m, 2H,
NCH2CH2CH2O). ESI-MS: 557.63 [M]. Anal. calcd. for C27H27BrF2N4O2:
C, 58.18; H, 4.88; N, 10.05. Found: C, 58.17; H, 4.89; N, 10.04.
A solution of intermediate 7 (0.63 g, 1.9 mmol), 6a (0.45 g,
1.8 mmol), and triethylamine (2 mL) in EtOH (20 mL) was heated to
reflux for 8 h. The solvent was evaporated under reduced pressure.
The residue was purified by silica gel column chromatography
(CH2Cl2:MeOH ¼ 100:2, v/v) to give 9a as pale yellow oil, 0.55 g
(65.1%). 1H NMR
d: 8.27 (s, 1H, TriazC3eH), 7.73 (s, 1H, TriazC5eH),
5.2.9. 1-((3-(4-Bromophenoxy)propyl)(4-methylbenzyl)amino)-2-
6.84e7.43 (m, 7H, AreH), 4.55 (s, 2H, C1eH), 3.93 (t, 2H, J ¼ 5.9 Hz,
OCH2), 3.29 (s, 2H, C3eH), 2.63 (t, 2H, J ¼ 6.9 Hz, NCH2CH2CH2O),
1.78 (m, 2H, NCH2CH2CH2O). ESI-MS: 469.66 [M þ 2]. Anal. calcd.
for C20H21BrF2N4O2: C, 51.40; H, 4.53; N, 11.99. Found: C, 51.38; H,
4.52; N, 11.97. The synthetic method for the compound 10a was
similar to the synthesis of compound 9a.
(2,4-difluorophenyl)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol (9f)
Yellow oil: 0.08 g (48.2%). 1H NMR
d: 8.06 (s,1H, TriazC3eH), 7.75
(s, 1H, TriazC5eH), 6.63e7.56 (m, 11H, AreH), 4.47 (d, 1H,
J ¼ 14.0 Hz, C1eHa), 4.38 (d, 1H, J ¼ 14.0 Hz, C1eHb), 3.71 (t, 2H,
J ¼ 5.8 Hz, OCH2), 3.43 (d, 1H, J ¼ 13.2 Hz, NCH2Ar), 3.30 (d, 1H,
J ¼ 13.2 Hz, NCH2Ar), 3.18 (d, 1H, J ¼ 13.8 Hz, C3eHa), 2.85 (d, 1H,
J ¼ 13.8 Hz, C3eHb), 2.47 (t, 2H, J ¼ 7.5 Hz, NCH2CH2CH2O), 2.30 (s,
3H, CH3), 1.70 (m, 2H, NCH2CH2CH2O). ESI-MS: 571.36 [M]. Anal.
calcd. for C28H29BrF2N4O2: C, 58.85; H, 5.12; N, 9.80. Found: C,
58.86; H, 5.13; N, 9.81.
5.2.5. Chemical synthesis of 1-((3-(4-bromophenoxy)propyl)(ethyl)
amino)-2-(2,4-difluorophenyl)-3-(1H-1,2,4-triazol-1-yl)propan-2-
ol (9b)
A solution of chloroethane (0.045 g, 0.7 mmol), 9a (0.18 g,
0.39 mmol), K2CO3 (0.15 g, 1.1 mmol), and KI (0.03 g, 0.18 mmol) in
acetonitrile (15 mL) was heated to reflux for 8 h. The mixture was
filtered and concentrated under reduced pressure. The residue was
purified by silica gel column chromatography (Hexane:EtOAc ¼ 2:1,
5.2.10. 1-((3-(4-Bromophenoxy)propyl)(4-fluorobenzyl)amino)-2-
(2,4-difluorophenyl)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol (9g)
Pale yellow solid: 0.13 g (47.1%). 1H NMR
d: 8.06 (s, 1H,
TriazC3eH), 7.76 (s, 1H, TriazC5eH), 6.64e7.56 (m, 11H, AreH), 4.50
(d, 1H, J ¼ 14.0 Hz, C1eHa), 4.39 (d, 1H, J ¼ 14.0 Hz, C1eHb), 3.72 (t,
2H, J ¼ 5.8 Hz, OCH2), 3.44 (d, 1H, J ¼ 13.4 Hz, NCH2Ar), 3.31 (d, 1H,
J ¼ 13.4 Hz, NCH2Ar), 3.18 (d, 1H, J ¼ 13.8 Hz, C3eHa), 2.84 (d, 1H,
J ¼ 13.8 Hz, C3eHb), 2.50 (t, 2H, J ¼ 7.1 Hz, NCH2CH2CH2O), 1.70 (m,
2H, NCH2CH2CH2O). ESI-MS: 575.68 [M]. Anal. calcd. for
C27H26BrF3N4O2: C, 56.36; H, 4.55; N, 9.74. Found: C, 56.35; H, 4.54;
N, 9.76.
v/v) to give 9b as pale yellow oil, 0.09 g (46.6%). 1H NMR
d: 8.13 (s,
1H, TriazC3eH), 7.84 (s, 1H, TriazC5eH), 6.69e7.56 (m, 7H, AreH),
4.55 (d, 1H, J ¼ 14.1 Hz, C1eHa), 4.44 (d, 1H, J ¼ 14.1 Hz, C1eHb),
3.78 (t, 2H, J ¼ 5.9 Hz, OCH2), 3.13 (d, 1H, J ¼ 13.8 Hz, C3eHa),
2.75 (d, 1H, J ¼ 13.8 Hz, C3eHb), 2.45 (t, 2H, J ¼ 6.9 Hz,
NCH2CH2CH2O), 2.33 (m, 2H, NCH2CH3), 1.68 (m, 2H,
NCH2CH2CH2O), 0.79 (t, 3H, NCH2CH3). ESI-MS: 497.51 [M þ 2].

S. Wang et al. / European Journal of Medicinal Chemistry 53 (2012) 292e299
297
5.2.11. Methyl 2-((3-(4-bromophenoxy)propyl)(2-(2,4-
5.2.16. 1-((3-(4-Bromophenoxy)propyl)(isobutyl)amino)-2-(2,4-
difluorophenyl)-2-hydroxyl-3-(1H-1,2,4-triazol-1-yl)propyl)amino)
acetate (9h)
difluorophenyl)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol (9m)
Yellow oil: 0.05 g (21.2%). 1H NMR
d: 8.13 (s, 1H, TriazC3eH), 7.89
Brown oil: 0.14 g (45.8%). 1H NMR
d: 8.11 (s, 1H, TriazC3eH), 7.76
(s, 1H, TriazC5eH), 6.13e7.38 (m, 7H, AreH), 4.41e4.58 (dd, 2H,
J ¼ 14.1 Hz, C1eH), 3.92 (t, 2H, J ¼ 5.9 Hz, OCH2), 3.54e3.58 (d, 1H,
J ¼ 11.4 Hz, C3eHa), 3.32e3.36 (d, 1H, J ¼ 11.4 Hz, C3eHb), 3.39e3.42
(m, 1H, CH2CH(CH3)2), 3.24e3.27 (m, 1H, CH2CH(CH3)2), 2.82e2.86
(s,1H, TriazC5eH), 6.68e7.54 (m, 7H, AreH), 4.56 (d,1H, J ¼ 14.3 Hz,
C1eHa), 4.49 (d, 1H, J ¼ 14.4 Hz, C1eHb), 3.79 (t, 2H, J ¼ 6.0 Hz,
OCH2), 3.66 (s, 1H, OCH3) 3.44 (d, 1H, J ¼ 13.7 Hz, C3eHa), 3.25 (s,
2H, NCH2CO), 2.83 (d, 1H, J ¼ 13.7 Hz, C3eHb), 2.79 (br, 1H,
NCH2CH2CH2O), 2.56 (br, 1H, NCH2CH2CH2O), 1.68 (m, 2H,
NCH2CH2CH2O). ESI-MS: 539.70 [M]. Anal. calcd. for
C23H25BrF2N4O4: C, 51.22; H, 4.67; N, 10.39. Found: C, 51.20; H, 4.68;
N, 10.41.
(t, 2H,
J
¼
6.9 Hz, NCH2CH2CH2O), 1.91e1.95 (m, 2H,
NCH2CH2CH2O), 1.86e1.92 (m, 1H, CH2CH(CH3)2), 0.86e0.93 (m, 6H,
CH(CH3)2). ESI-MS: 523.65 [M]. Anal. calcd. for C24H29BrF2N4O2: C,
55.07; H, 5.58; N, 10.70. Found: C, 55.04; H, 5.56; N, 10.72.
5.2.17. 2-(2,4-Difluorophenyl)-1-((3-phenoxypropyl)amino)-3-
(1H-1,2,4-triazol-1-yl)propan-2-ol (10a)
5.2.12. Ethyl 2-((3-(4-bromophenoxy)propyl)(2-(2,4-
difluorophenyl)-2-hydroxy-3-(1H-1,2,4-triazol-1-yl)propyl)amino)
acetate (9i)
Yellow oil: 0.16 g (58.0%). 1H NMR
d: 8.27 (s, 1H, TriazC3eH), 7.73
(s, 1H, TriazC5eH), 6.84e7.43 (m, 7H, AreH), 4.55 (s, 2H, C1e2H),
3.93 (t, 2H, J ¼ 5.9 Hz, OCH2), 3.29 (s, 2H, C3e2H), 2.63 (t, 2H,
Yellow oil: 0.09 g (45.3%). 1H NMR
d: 8.14 (s, 1H, TriazC3eH),
7.77 (s, 1H, TriazC5eH), 6.68e7.59 (m, 7H, AreH), 4.57 (d, 1H,
J ¼ 14.3 Hz, C1eHa), 4.50 (d, 1H, J ¼ 14.3 Hz, C1eHb), 4.12 (m, 2H,
COOCH2CH3), 3.80 (t, 2H, J ¼ 5.7 Hz, OCH2), 3.45 (d, 1H, J ¼ 14.1 Hz,
C3eHa), 3.22 (s, 2H, NCH2CO), 2.80 (d, 1H, J ¼ 14.1 Hz, C3eHb), 2.53
(t, 2H, J ¼ 6.7 Hz, NCH2CH2CH2O), 1.70 (m, 2H, NCH2CH2CH2O),
1.24 (t, 3H, CH2CH3). ESI-MS: 552.05 [M ꢀ 1]. Anal. calcd. for
C24H27BrF2N4O4: C, 52.09; H, 4.92; N, 10.12. Found: C, 52.08; H,
4.91; N, 10.11.
J ¼ 6.9 Hz, NCH2CH2CH2O), 1.78 (m, 2H, NCH2CH2CH2O). 13C NMR
d:
163.78, 161.79, 159.95, 158.60, 157.98, 151.24, 144.67, 129.93, 129.43,
124.89, 120.85, 114.35, 111.51, 104.22, 73.33, 65.95, 55.93, 54.37,
47.38, 29.40. ESI-MS: 389.80 [M þ 1]. Anal. calcd. for C20H22F2N4O2:
C, 61.85; H, 5.71; N, 14.42. Found: C, 61.83; H, 5.69; N, 14.43.
5.2.18. 2-(2,4-Difluorophenyl)-1-(ethyl(3-phenoxypropyl)amino)-
3-(1H-1,2,4-triazol-1-yl)propan-2-ol (10b)
Yellow oil: 0.08 g (51.3%). 1H NMR
d: 8.06 (s, 1H, TriazC3eH), 7.89
5.2.13. tert-Butyl-2-((3-(4-bromophenoxy)propyl)(2-(2,4-
difluorophenyl)-2-hydroxy-3-(1H-1,2,4-triazol-1-yl)propyl)amino)
acetate (9j)
(s, 1H, TriazC5eH), 6.79e7.77 (m, 8H, AreH), 4.52 (d, 1H, J ¼ 14.1 Hz,
C1eHa), 4.46 (d, 1H, J ¼ 14.1 Hz, C1eHb), 3.83 (t, 2H, J ¼ 5.9 Hz,
OCH2), 3.12 (d, 1H, J ¼ 13.8 Hz, C3eHa), 2.77 (d, 1H, J ¼ 13.8 Hz,
C3eHb), 2.48 (t, 2H, J ¼ 6.9 Hz, NCH2CH2CH2O), 2.38 (m, 2H,
NCH2CH3), 1.71(m, 2H, NCH2CH2CH2O), 0.88 (t, 3H, J ¼ 6.7 Hz,
NCH2CH3). ESI-MS: 417.65 [M þ 1]. Anal. calcd. for C22H26F2N4O2: C,
63.45; H, 6.29; N, 13.45. Found: C, 63.43; H, 6.27; N, 13.44.
Yellow oil: 0.08 g (43.7%). 1H NMR
d: 8.22 (s, 1H, TriazC3eH),
7.72 (s, 1H, TriazC5eH), 6.76e7.42 (m, 7H, AreH), 4.51 (s, 2H,
C1e2H), 3.71 (t, 2H, J ¼ 5.7 Hz, OCH2), 3.22 (d, 1H, J ¼ 14.1 Hz,
C3eHa), 3.15 (s, 2H, NCH2CO), 2.97 (d, 1H, J ¼ 14.1 Hz, C3eHb),
2.58(t, 2H,
J
¼
6.7 Hz, NCH2CH2CH2O), 1.62 (m, 2H,
NCH2CH2CH2O), 1.36 (s, 9H, C(CH3)3). ESI-MS: 581.46 [M]. Anal.
calcd. for C26H31BrF2N4O4: C, 53.71; H, 5.37; N, 9.64. Found: C,
53.68; H, 5.35; N, 9.62.
5.2.19. 2-(2,4-Difluorophenyl)-1-((3-phenoxypropyl)(propyl)
amino)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol (10c)
Brown oil: 0.12 g (45.4%).1H NMR
d: 8.12 (s,1H, TriazC3eH), 7.78 (s,
1H, TriazC5eH), 6.76e7.54 (m, 8H, AreH), 4.52 (d, 1H, J ¼ 14.2 Hz,
C1eHa), 4.44 (d,1H, J ¼ 14.2 Hz, C1eHb), 3.82 (t, 2H, J ¼ 5.7 Hz, OCH2),
3.11 (d,1H, J ¼ 14.1 Hz, C3eHa), 2.76 (d,1H, J ¼ 14.1 Hz, C3eHb), 2.47 (t,
2H, J ¼ 7.2 Hz, NCH2CH2CH2O), 2.25 (t, 2H, NCH2CH2CH3),1.70 (m, 2H,
NCH2CH2CH2O), 1.24 (m, 2H, NCH2CH2CH3), 0.72 (t, 3H, J ¼ 7.0 Hz,
5.2.14. 1-(Allyl(3-(4-bromophenoxy)propyl)amino)-2-(2,4-
difluorophenyl)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol (9k)
Brown oil: 0.13 g (40.2%). 1H NMR
d: 8.13 (s, 1H, TriazC3eH), 7.78
(s,1H, TriazC5eH), 6.69e7.54 (m, 7H, AreH), 5.62 (m,1H, NCH2CH]
CH2), 5.06 (d, 1H, J ¼ 10.2 Hz, NCH2CH]CH2), 4.98 (d, 1H,
J ¼ 17.3 Hz, NCH2CH]CH2), 4.54 (d, 1H, J ¼ 14.2 Hz, C1eHa), 4.45 (d,
1H, J ¼ 14.2 Hz, C1eHb), 3.78 (t, 2H, J ¼ 5.7 Hz, OCH2), 3.13 (d, 1H,
J ¼ 14.1 Hz, C3eHa), 2.96 (m, 1H, NCH2CH]CH2), 2.86 (m, 1H,
NCH2CH]CH2), 2.78 (d, 1H, J ¼ 14.1 Hz, C3eHb), 2.50 (t, 2H,
J ¼ 6.7 Hz, NCH2CH2CH2O), 1.70 (m, 2H, NCH2CH2CH2O). ESI-MS:
507.65 [M]. Anal. calcd. for C23H25BrF2N4O2: C, 54.45; H, 4.97; N,
11.04. Found: C, 54.44; H, 4.96; N, 11.06.
NCH2CH2CH3). 13C NMR
d: 163.65, 161.65, 159.90, 158.64, 157.88,
150.87, 144.76, 129.38, 126.63, 120.79, 120.45, 114.46, 104.20, 71.57,
65.34, 59.32, 57.00, 56.39, 51.97, 29.65, 27.09, 20.01, 11.48. ESI-MS:
429.35 [M ꢀ 1]. Anal. calcd. for C23H28F2N4O2: C, 64.17; H, 6.56; N,
13.01. Found: C, 64.15; H, 6.54; N, 13.00.
5.2.20. 1-(Butyl(3-phenoxypropyl)amino)-2-(2,4-difluorophenyl)-
3-(1H-1,2,4-triazol-1-yl)propan-2-ol (10d)
Brown oil: 0.09 g (45.4%). 1H NMR
d: 8.12 (s, 1H, TriazC3eH), 7.78
5.2.15. 1-((3-(4-Bromophenoxy)propyl)(prop-2-yn-1-yl)amino)-2-
(s, 1H, TriazC5eH), 6.76e7.54 (m, 8H, AreH), 4.53 (d, 1H, J ¼ 14.1 Hz,
C1eHa), 4.43 (d, 1H, J ¼ 14.1 Hz, C1eHb), 3.83 (t, 2H, J ¼ 5.9 Hz,
OCH2), 3.12 (d, 1H, J ¼ 14.1 Hz, C3eHa), 2.78 (d, 1H, J ¼ 14.1 Hz,
C3eHb), 2.45 (t, 2H, J ¼ 7.5 Hz, NCH2CH2CH2O), 2.29 (t, 2H,
NCH2CH2CH2CH3), 1.69 (m, 2H, NCH2CH2CH2O), 1.10e1.20 (m, 4H,
NCH2CH2CH2CH3), 0.80 (t, 3H, NCH2CH2CH2CH3). ESI-MS: 443.41
[M ꢀ 1]. Anal. calcd. for C24H30F2N4O2: C, 64.85; H, 6.80; N, 12.60.
Found: C, 64.83; H, 6.79; N, 12.58.
(2,4-difluorophenyl)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol (9l)
Pale green oil: 0.07 g (33.6%). 1H NMR
d: 8.06 (s, 1H, TriazC3eH),
7.79 (s, 1H, TriazC5eH), 6.71e7.51 (m, 8H, AreH), 4.56 (d, 1H,
J ¼ 14.3 Hz, C1eHa), 4.50 (d, 1H, J ¼ 14.3 Hz, C1eHb), 3.82 (t, 2H,
J ¼ 5.7 Hz, OCH2), 3.30 (d, 1H, J ¼ 13.9 Hz, NCH2C^CH), 3.21 (d, 1H,
J ¼ 13.9 Hz, NCH2C^CH), 3.12 (d, 1H, J ¼ 14.1 Hz, C3eHa), 2.79 (d,
1H, J ¼ 14.1 Hz, C3eHb), 2.65 (s, 2H, NCH2C^CH), 2.53 (t, 2H,
J ¼ 6.7 Hz, NCH2CH2CH2O), 1.74 (m, 2H, NCH2CH2CH2O). 13C NMR
d:
163.79, 161.75, 159.85, 157.93, 157.74, 151.18, 144.59, 132.27, 129.55,
125.57, 116.18, 113.01, 111.55, 104.27, 77.94, 73.30, 73.12, 65.60,
58.79, 55.92, 51.94, 43.49, 27.06. ESI-MS: 505.71 [M]. Anal. calcd. for
C23H23BrF2N4O2: C, 54.66; H, 4.59; N, 11.09. Found: C, 54.65; H,
4.59; N, 11.07.
5.2.21. 1-(Benzyl(3-phenoxypropyl)amino)-2-(2,4-difluorophenyl)-
3-(1H-1,2,4-triazol-1-yl)propan-2-ol (10e)
Pale yellow oil: 0.15 g (55.8%). 1H NMR
d: 8.03 (s, 1H, TriazC3eH),
7.73 (s, 1H, TriazC5eH), 6.74e7.29 (m, 13H, AreH), 4.46 (d, 1H,
J ¼ 14.1 Hz, C1eHa), 4.37 (d, 1H, J ¼ 14.1 Hz, C1eHb), 3.78 (t, 2H,

298
S. Wang et al. / European Journal of Medicinal Chemistry 53 (2012) 292e299
J ¼ 5.6 Hz, OCH2), 3.52 (d, 1H, J ¼ 13.4 Hz, NCH2Ar), 3.34 (d, 1H,
J ¼ 13.4 Hz, NCH2Ar), 3.19 (d, 1H, J ¼ 13.8 Hz, C3eHa), 2.87 (d, 1H,
J ¼ 13.8 Hz, C3eHb), 2.52 (t, 2H, J ¼ 6.5 Hz, NCH2CH2CH2O), 1.72 (m,
2.78 (d,1H, J ¼ 14.1 Hz, C3eHb), 2.70 (br,1H, NCH2CH2CH2O), 2.50 (br,
1H, NCH2CH2CH2O), 1.68 (m, 2H, NCH2CH2CH2O), 1.42 (s, 9H,
C(CH3)3). ESI-MS: 503.58 [M þ 1]. Anal. calcd. for C26H32F2N4O4: C,
62.14; H, 6.42; N, 11.15. Found: C, 62.13; H, 6.45; N, 11.14.
2H, NCH2CH2CH2O). 13C NMR
d: 163.66, 161.67, 159.80, 158.56,
157.83, 150.90, 144.65, 137.74, 129.41, 129.32 128.89, 128.47, 126.25,
120.79, 114.36, 111.48, 104.19, 72.30, 65.50, 59.53, 58.60, 56.18,
52.13, 26.65. ESI-MS: 479.50 [M þ 1]. Anal. calcd. for C27H28F2N4O2:
C, 67.77; H, 5.90; N, 11.71. Found: C, 67.75; H, 5.88; N, 11.73.
5.2.27. 1-(Allyl(3-phenoxypropyl)amino)-2-(2,4-difluorophenyl)-3-
(1H-1,2,4-triazol-1-yl)propan-2-ol (10k)
Yellow oil: 0.07 g (36.8%). 1H NMR
d: 8.11 (s, 1H, TriazC3eH), 7.77
(s,1H, TriazC5eH), 6.77e7.54 (m, 8H, AreH), 5.63 (m,1H, NCH2CH]
CH2), 5.06 (d, 1H, J ¼ 9.6 Hz, NCH2CH]CH2), 4.98 (d, 1H, J ¼ 17.3 Hz,
NCH2CH]CH2), 4.52 (d, 1H, J ¼ 14.2 Hz, C1eHa), 4.46 (d, 1H,
J ¼ 14.2 Hz, C1eHb), 3.83 (t, 2H, J ¼ 5.7 Hz, OCH2), 3.13 (d, 1H,
J ¼ 14.1 Hz, C3eHa), 2.98 (m, 1H, NCH2CH]CH2), 2.87 (m, 1H,
NCH2CH]CH2), 2.78 (d, 1H, J ¼ 14.1 Hz, C3eHb), 2.52 (t, 2H,
J ¼ 6.7 Hz, NCH2CH2CH2O), 1.72 (m, 2H, NCH2CH2CH2O). ESI-MS:
427.51 [M ꢀ 1]. Anal. calcd. for C23H26F2N4O2: C, 64.47; H, 6.12; N,
13.08. Found: C, 64.49; H, 6.11; N, 13.06.
5.2.22. 2-(2,4-Difluorophenyl)-1-((4-methylbenzyl)(3-
phenoxypropyl)amino)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol (10f)
Yellow oil: 0.14 g (46.3%). 1H NMR
d: 8.06 (s, 1H, TriazC3eH), 7.76
(s, 1H, TriazC5eH), 6.74e7.53 (m, 12H, AreH), 4.46 (d, 1H,
J ¼ 14.0 Hz, C1eHa), 4.39 (d, 1H, J ¼ 14.0 Hz, C1eHb), 3.78 (t, 2H,
J ¼ 5.6 Hz, OCH2), 3.46 (d, 1H, J ¼ 13.3 Hz, NCH2Ar), 3.32 (d, 1H,
J ¼ 13.3 Hz, NCH2Ar), 3.18 (d, 1H, J ¼ 13.9 Hz, C3eHa), 2.86 (d, 1H,
J ¼ 13.9 Hz, C3eHb), 2.50 (t, 2H, J ¼ 7.1 Hz, NCH2CH2CH2O), 2.30 (s,
3H, AreCH3), 1.71 (m, 2H, NCH2CH2CH2O). ESI-MS: 493.54 [M þ 1].
Anal. calcd. for C28H30F2N4O2: C, 68.28; H, 6.14; N, 11.37. Found: C,
68.30; H, 6.13; N, 11.38.
5.2.28. 2-(2,4-Difluorophenyl)-1-((3-phenoxypropyl)(prop-2-yn-1-
yl)amino)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol (10l)
Brown oil: 0.09 g (35.6%). 1H NMR
d: 8.23 (s, 1H, TriazC3eH), 7.73
5.2.23. 2-(2,4-Difluorophenyl)-1-((4-fluorobenzyl)(3-
(s, 1H, TriazC5eH), 6.80e7.37 (m, 8H, AreH), 4.52 (s, 2H, C1e2H),
3.72 (t, 2H, J ¼ 5.7 Hz, OCH2), 3.40 (d, 1H, J ¼ 13.9 Hz,
NCH2C^CH), 3.27 (d, 1H, J ¼ 13.9 Hz, NCH2C^CH), 3.04 (d, 1H,
J ¼ 14.1 Hz, C3eHa), 2.82 (d, 1H, J ¼ 14.1 Hz, C3eHb), 2.64 (s, 1H,
NCH2C^CH), 2.52 (t, 2H, J ¼ 6.7 Hz, NCH2CH2CH2O), 1.68 (m, 2H,
phenoxypropyl)amino)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol (10g)
Pale brown solid: 0.16 g (45.9%). 1H NMR
d: 8.05 (s,1H, TriazC3eH),
7.75 (s, 1H, TriazC5eH), 6.75e7.56 (m, 12H, AreH), 4.49 (d, 1H,
J ¼ 14.0 Hz, C1eHa), 4.39 (d, 1H, J ¼ 14.0 Hz, C1eHb), 3.78 (t, 2H,
J ¼ 5.6 Hz, OCH2), 3.44 (d, 1H, J ¼ 13.4 Hz, NCH2Ar), 3.34 (d, 1H,
J ¼ 13.4 Hz, NCH2Ar), 3.18 (d, 1H, J ¼ 13.9 Hz, C3eHa), 2.85 (d, 1H,
J ¼ 13.9 Hz, C3eHb), 2.50 (t, 2H, J ¼ 7.1 Hz, NCH2CH2CH2O),1.71 (m, 2H,
NCH2CH2CH2O). ESI-MS: 497.63 [M þ 1]. Anal. calcd. for C27H27F3N4O2:
C, 65.31; H, 5.48; N, 11.28. Found: C, 65.30; H, 5.46; N, 11.26.
NCH2CH2CH2O). ESI-MS: 427.73 [M
þ
1]. Anal. calcd. for
C23H24F2N4O2: C, 64.78; H, 5.67; N, 13.14. Found: C, 64.75; H, 5.65;
N, 13.13.
6. Molecular docking
5.2.24. Methyl 2-((2-(2,4-difluorophenyl)-2-hydroxy-3-(1H-1,2,4-
triazol-1-yl) propyl)(3-phenoxypropyl)amino)acetate (10h)
The 3D structures of the synthesized compounds were built by the
builder module within Sybyl-X 1.2 software package. The R isomers
were selected for molecular docking [26]. The active site was defined
the same with our previous reports [24,31,32]. Before docking, we
firstly tested the ability of Gold 4.1.2 [33] software to reproduce the
binding pose of the ligands in the crystal structures of the CYP51
family. Twelve crystal structures of CYP51 in complex with various
ligands (PDB codes: 1EA1, 1E9X, 2W09, 2W0A, 2W0B, 2WX2, 2WUZ,
3GW9, 3K1O, 3L4D, 3I3K, 3LD6) [34e40] were used as the test set and
all the ligands were docked with default parameters. The results
indicated that Gold software with Goldscore function showed satis-
fying accuracy with the average RMSD of 1.37 Å. Further optimization
of the docking parameters did not yield better results. Therefore, Gold
4.1.2 with default parameters was used for molecular docking. The
docking conformation was selected according to the docking score
and visual inspection. MVD 4.3.0 [41] was also used to re-dock the
compounds to confirm the robustness of the docking pose.
Pale yellow oil: 0.09 g (50.3%). 1H NMR
d: 8.08 (s,1H, TriazC3eH),
7.74 (s, 1H, TriazC5eH), 6.75e7.53 (m, 8H, AreH), 4.54 (d, 1H,
J ¼ 14.3 Hz, C1eHa), 4.51 (d, 1H, J ¼ 14.3 Hz, C1eHb), 4.12 (m, 2H,
COOCH2CH3), 3.83 (t, 2H, J ¼ 5.7 Hz, OCH2), 3.66 (s, 3H, OCH3), 3.44
(d, 1H, J ¼ 14.1 Hz, C3eHa), 3.28 (s, 2H, NCH2CO), 2.86 (d, 1H,
J ¼ 14.1 Hz, C3eHb), 2.76 (br, 1H, NCH2CH2CH2O), 2.62 (br, 1H,
NCH2CH2CH2O), 1.70 (m, 2H, NCH2CH2CH2O). 13C NMR
d: 172.29,
163.73, 161.74, 159.78, 158.57, 157.82, 150.95, 144.63, 129.97, 129.44,
125.39, 120.83, 114.35, 111.45, 104.08, 73.62, 64.97, 61.26, 56.48,
55.91, 53.44, 51.85, 27.41. ESI-MS: 461.52 [M þ 1]. Anal. calcd. for
C23H26F2N4O4: C, 59.99; H, 5.69; N, 12.17. Found: C, 59.98; H, 5.71;
N, 12.15.
5.2.25. Ethyl 2-((2-(2,4-difluorophenyl)-2-hydroxy-3-(1H-1,2,4-
triazol-1-yl) propyl)(3-phenoxypropyl)amino)acetate (10i)
Pale yellow oil: 0.13 g (46.9%). 1H NMR
d: 8.09 (s, 1H, TriazC3eH),
7.74 (s, 1H, TriazC5eH), 6.74e7.54 (m, 8H, AreH), 4.54 (d, 1H,
J ¼ 14.3 Hz, C1eHa), 4.51 (d, 1H, J ¼ 14.3 Hz, C1eHb), 4.12 (m, 2H,
COOCH2CH3), 3.82 (t, 2H, J ¼ 5.7 Hz, OCH2), 3.42 (d, 1H, J ¼ 14.1 Hz,
C3eHa), 3.23 (s, 2H, NCH2CO), 2.82 (d, 1H, J ¼ 14.1 Hz, C3eHb), 2.72
(br, 1H, NCH2CH2CH2O), 2.58 (br, 1H, NCH2CH2CH2O), 1.68 (m, 2H,
NCH2CH2CH2O), 1.23 (t, 3H, CH2CH3). ESI-MS: 475.76 [M þ 1]. Anal.
calcd. for C24H28F2N4O4: C, 60.75; H, 5.95; N, 11.81. Found: C, 60.76;
H, 5.94; N, 11.82.
Acknowledgments
This work was supported by the National Natural Science
Foundation of China (Grant Nos. 30930107), Science and Tech-
nology Commission of Shanghai (Grant Nos. 10431902100), the 863
Hi-Tech Program of China (Grant 2012AA020302) and Shanghai
Municipal Health Bureau (Grant XYQ2011038).
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