Synthesis and anti-hyperlipidemic evaluation of N-(benzoylphenyl)-5-fluoro- 1H-indole-2-carboxamide derivatives in Triton WR-1339-induced hyperlipidemic rats

Article abstract of DOI:10.3390/molecules15095840

The lipid-lowering activity of a series of novel N-(benzoylphenyl)-5- fluoro-1H-indole-2-carboxamide derivatives has been studied in Triton WR-1339-induced hyperlipidemia in rats. The test animals were divided into four groups: control, hyperlipidemic, compound + 4% DMSO [C1: N-(2-benzoylphenyl)-5- fluoro-1H-indole-2-carboxamide (1), C2: N-(3-benzoylphenyl)-5-fluoro-1H-indole- 2-carboxamide (2), C3: N-(4-benzoylphenyl)-5-fluoro-1H-indole-2-carboxamide (3)]-treated and bezafibrate (BF)-treated. At a dose of 15 mg/Kg body weight, compounds 2, 3 and BF significantly reduced elevated plasma triglycerodes levels after 12 h. Moreover, high density lipoproteincholesterol levels were significantly increased in all treated groups after 12 h compared to the hyperlipidemic control group, except for C1 which was inactive. In sum, it may be stated that the results of the present study demonstrated new properties of some N-(benzoylphenyl)-5-fluoro-1H-indole-2-carboxamide derivatives as potent lipid lowering agents and these beneficial activities may contribute to their cardioprotective and antiatherosclerotic role.

Full text of DOI:10.3390/molecules15095840

Molecules 2010, 15, 5840-5849; doi:10.3390/molecules15095840
OPEN ACCESS
molecules
ISSN 1420-3049
www.mdpi.com/journal/molecules
Article
Synthesis and Anti-Hyperlipidemic Evaluation of
N-(Benzoylphenyl)-5-fluoro-1H-indole-2-carboxamide
Derivatives in Triton WR-1339-Induced Hyperlipidemic Rats
Ghassan Shattat 1,*, Rania Al-Qirim 2, Yusuf Al-Hiari 2, Ghassan Abu Sheikha 1, Tariq Al-Qirim 1,
Waseem El-Huneidi 1 and Moyad Shahwan 1
1
Faculty of Pharmacy, Al-Zaytoonah Private University, Amman, Jordan
2
Faculty of Pharmacy, University of Jordan, Amman, Jordan
* Author to whom correspondence should be addressed; E-Mail: gassan10@yahoo.com;
Tel.: 00962 79648 8599; Fax: 00962 6429 1432.
Received: 23 June 2010; in revised form: 18 August 2010 / Accepted: 20 August 2010 /
Published: 26 August 2010
Abstract: The lipid-lowering activity of a series of novel N-(benzoylphenyl)-5-fluoro-1H-
indole-2-carboxamide derivatives has been studied in Triton WR-1339-induced
hyperlipidemia in rats. The test animals were divided into four groups: control,
hyperlipidemic, compound + 4% DMSO [C1: N-(2-benzoylphenyl)-5-fluoro-1H-indole-2-
carboxamide (1), C2: N-(3-benzoylphenyl)-5-fluoro-1H-indole-2-carboxamide (2), C3: N-
(4-benzoylphenyl)-5-fluoro-1H-indole-2-carboxamide (3)]-treated and bezafibrate (BF)-
treated. At a dose of 15 mg/Kg body weight, compounds 2, 3 and BF significantly reduced
elevated plasma triglycerodes levels after 12 h. Moreover, high density lipoprotein-
cholesterol levels were significantly increased in all treated groups after 12 h compared to
the hyperlipidemic control group, except for C1 which was inactive. In sum, it may be
stated that the results of the present study demonstrated new properties of some N-
(benzoylphenyl)-5-fluoro-1H-indole-2-carboxamide derivatives as potent lipid lowering
agents and these beneficial activities may contribute to their cardioprotective and
antiatherosclerotic role.
Keywords: Triton WR-1339-induced hyperlipidemic rats; N-(benzoylphenyl)-5-fluoro-
1H-indole-2-carboxamides;
high-density
lipoprotein-cholesterol;
triglycerides;
hypolipidemic activity

Molecules 2010, 15
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1. Introduction
Hyperlipidemia is defined as an elevation of lipids in plasma [1]. Several studies have showed that
an intimate correlation exists between coronary heart diseases and hyperlipidemia [2,3], consequently
a rational approach to the treatment and prevention of coronary heart diseases could be by decreasing
any elevated levels of lipids in plasma [4]. For that purpose, many studies have been conducted to
evaluate the potential hypolipidemic effects of synthetic and naturally occurring compounds.
Triton WR-1339-induced hyperlipidemic rats are a globally accepted model used to evaluate
potential hypolipidemic drugs [5]. Triton WR-1339 is a nonionic detergent that prevents catabolism of
triacylglycerol-rich lipoproteins by lipo-protein lipase and is commonly used for in vivo determination
of triacylglycerol production, and very low density lipoprotein (VLDL) secretion or clearance
rate [6,7].
Treatment with fibrates, a widely used class of lipid-modifying agents, results in a significant
decrease in plasma triglycerides (79%) and is usually associated with a decrease in low density
lipoprotein (LDL), cholesterol (11%), and an increase in high density lipoprotein (HDL)-cholesterol
concentrations (27%) [8]. The major pharmacological mechanism of fibrates, including bezafibrate, is
by the induction of lipoprotein lipase and reduction of apolipoprotein C-III synthesis leading to
increased hydrolysis of triglycerides (TG) [9,10].
Some indole derivatives are well-known for their diverse pharmacological effects including a
hypolipidemic effect [11-15]. Although studies have shown the potential role for indole-2-
carboxamide derivatives as anti-allergics [16], and antioxidants [17,18],to the best of our knowledge
N-(benzoylphenyl)-5-fluoro-1H-indole-2-carboxamide derivatives have not been investigated as
potential lipid-lowering agents. In the present study, we aimed to synthesize a new series of ethyl-5-
fluoro-1H-indole-2-carboxamide derivatives and to investigate their hypolipidemic activity using
Triton WR-1339 induced hyperlipidemic rats as a model.
2. Results and Discussion
2.1. Chemical Studies
A novel series of N-(benzoylphenyl)-5-fluoro-1H-indole-2-carboxamides 1-5 (Scheme 1) were
prepared in the course of this work. The target compounds were synthesized in one step by the
coupling reaction between ethyl-5-fluoro-1H-indole-2-carboxylate (6) and an excess of the
corresponding aminobenzophenones 7-11 in the presence of sodium ethoxide in DMF or DMSO at
150–190 ºC, as shown in the Scheme. The reaction mixtures were purified using column
chromatography to afford the desired compounds. These reaction conditions gave the targets in
relatively low yields (6%–37%). The harsh reaction conditions (150–190 ºC) and the chromatographic
separation led to the decomposition and loss of appreciable amounts of the targets. Although the yields
were low, enough pure amounts of each compound could be collected for the
pharmacological evaluation.

Molecules 2010, 15
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Scheme 1. Synthesis of 5-fluoro-1H-indole-2-carboxamides from un-substituted and
substituted aminobenzophenones.
Reagents and Conditions: i) sodium ethoxide, DMF or DMSO, 150–190 ºC.
2.2. Pharmacological Studies
2.2.1. Induction of Hyperlipidemia by Triton WR-1339
The levels of plasma total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol
(HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels of all groups treated for 12 h after
Triton administration are shown in Figure 1. In comparison with the normal control group (CG), Triton
WR-1339 caused a significant increase in cholesterol and triglyceride plasma concentrations measured
12 h after Triton injection. After 12 h, the plasma total cholesterol was increased by (32%) and
triglycerides by more than eight times.
Triton WR-1339 caused a significant decrease in HDL cholesterol levels in the hyperlipidemic
control (HG), at 12 h after Triton administration, in comparison with the CG. In fact, the decrease of
plasma total cholesterol concentration in the HG was 28% after 12 h as compared to the CG. When the
HG group was compared with CG, we observed that after 12 h from Triton injection (Figure 1), LDL
cholesterol increased by (208%)

Molecules 2010, 15
5843
Figure 1. Effect of Triton-WR1339 on lipid profile after 12 h.
500
**
450
400
CG
350
HG
300
250
200
150
**
100
**
*
50
0
TC
LDL-C
HDL-C
TG
Values are means ± SEM from eight animals in each group. CG: control group; HG:
hyperlipidemic control group; TC: total cholesterol; TG: triglyceride; HDL-C: high-density
lipoprotein cholesterol; LDL-C: low density lipoprotein cholesterol. HG is compared to CG.
* p < 0.001, ** p < 0.0001.
2.2.2. Effect of Compounds 1, 2, 3 and Bezafibrate on Rat Plasma Lipid Profile
The plasma total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL-C) and low-
density lipoprotein (LDL-C) levels of bezafibrate (BF) and compound 1, 2 and 3-treated rats 12 h after
Triton administration are shown in Table 1. Importantly, the elevated plasma TG levels produced by
Triton WR-1339 administration were significantly suppressed by BF (79%), compound 2 (90%) and
compound 3 (83%) after 12 h with respect to the hyperlipidemic control HG. No significant difference
in TG level was observed with compound 1, compared to HG-treated rats.
Table 1. Effect of the novel C1, C2, C3 and bezafibrate on plasma lipid levels in Triton
WR-1339-induced hyperlipemic rats after 12 h.
Lipid profile
TC (mg/dL)
TG (mg/dL)
HDL-C(mg/dL)
LDL-C (mg/dL)
CG
HG
C 1
C 2
C 3
BF
86.2 ± 7.2
114.2 ± 6.6
134.3 ± 12.2
124.0 ± 4.9
114.0 ± 0.98
125.3 ± 4.0
55.2 ± 4.5
445.0 ± 14.5
533.2 ± 16.3
46.0 ± 5.4 b
75.3 ± 7.0 b
95.6 ± 5.0 b
54.6 ± 4.1
39.5 ± 6.7
42.2 ± 5.7
73.6 ± 2.3 b
60.5 ±10.3 a
50.2 ± 3.7 a
20.5 ± 1.9
63.2 ± 1.6
65.8 ± 1.3
41.2 ± 2.6 b
38.5 ± 2.3 b
56.0 ± 3.1
Values are means ± SEM from eight animals in each group. CG: normal control group; HG:
hyperlipidemic  4% DMSO control group; C1: compound 1  4% DMSO; C2: compound 2  4%
DMSO; C3: compound 3  4% DMSO; BF: bezafibrate  4% DMSO; TC: total cholesterol; TG:
triglyceride; HDL-C: high-density lipoprotein cholesterol; LDL-C: low-density lipoprotein
cholesterol. C1, C2, C3 and BF are compared with HG. a p < 0.01, b p < 0.0001.

Molecules 2010, 15
5844
HDL-cholesterol levels were significantly increased 12 h after Triton administration ( 86%) in the
compound 2 and (+53% and 27%) in compound 3 and BF-treated animals, respectively, compared to
HG (Table 1). In contrast there was no significant change in TG levels after 12 h with compound 1
with respect to hyperlipidemic control HG.
With the exception of compound 1 and BF, all treated groups showed an obvious and significant
reduction in plasma LDL-C levels after 12 h (Table 1). In fact, it was found that LDL-C levels were
reduced by 35% and 39% after 12 h by compound 2 and compound 3, respectively, compared to HG-
treated rats. After 12 h of treatment, no significant differences in plasma total cholesterol levels
between any treated groups (BF, compounds 1, 2 and 3) were observed in comparison to HG-treated
rats (Table 1). In this study, compound 4 and 5 were not biologically tested because they are
derivatives of compound 2 which already revealed inactive
The results of this study demonstrated the potential hypolipidemic effect of the tested 5-fluoro-1H-
indole-2-carboxamide derivatives in Triton WR-1339 induced hyperlipidemic rats. Compounds 2 and
3 significantly reduced serum TG and increased serum HDL. These observations could be explained
by understanding the mechanism through which Triton WR-1339 induces hyperlipidemia in adults rats
after parenteral administration. The maximum plasma total cholesterol and triglyceride levels were
reached at 20 h followed by a decline to normal values [19,20]. In the course of this study, the same
model gave a similar pattern of lipid profile changes 12 h after Triton WR-1339 administration
(Figure 1). In fact, triglyceride and cholesterol levels started to increase after 7 hours and reach the
peak in 20 h, followed by a decline in triglyceride and cholesterol levels.
Clearly, our results showed that both compounds 2 and 3 at a dose of 15 mg/kg body weight were
able to significantly decrease serum triglycerides levels. The large decrease in plasma HDL-C levels
due to Triton WR-1339 injection results mostly from a progressive displacement of the apo A-1
protein from the HDL surface, without loss of lipid [21]. Mean while the large increase in plasma TG
levels due to Triton administration results mostly from an increase of very low-density lipoprotein
(VLDL) secretion by the liver accompanied by strong reduction of VLDL and LDL catabolism [22].
Thus, since the proportion of triglyceride in VLDL is many times higher than cholesterol, it is not
surprising that the hypolipidemic activity of compounds 2 and 3 was significantly higher for
triglycerides than for cholesterol. This result suggests that our compounds are able to restore, at least
partially, catabolism of B-lipoproteins as hypothesized by many studies with other lipid-lowering
agents [23,24].
In addition, both compounds 2 and 3 increased HDL levels, which are known for their preventive
role against atherogenesis. HDL plays an important role in facilitating the mobilization of triglycerides
and cholesterol from plasma to liver where it undergoes catabolism and then eliminated in the form of
bile acids [25,26].
Promisingly, compounds 2 and 3 at a dose of 15 mg/kg body weight 12 h after Triton injection is
more significant than the reduction induced by bezafibrate at a dose of 100 mg/kg body weight, which
in this study has been used as standard reference hypolipidemic drug. Furthermore, total cholesterol
levels were not significantly changed which agrees with the mechanism of action of fibrates in that
their total cholesterol-lowering activity is not strongly marked, but the triglycerides decreasing effect
of them is very impressive especially by stimulation of the gene expression of lipoprotein lipase [27].

Molecules 2010, 15
3. Experimental
3.1. General
5845
The reaction mixtures were purified by column chromatography to afford the desired compounds.
1
Melting points were measured using a Gallenkamp melting point apparatus and are uncorrected. H-
13
NMR and C-NMR spectra were collected on a Varian Oxford NMR300 spectrometer. The samples
were dissolved in CDCl3 at a concentration of 0.3–0.7 wt-%. High-resolution mass spectra (HRMS)
were measured in positive ion mode using electrospray ion trap (ESI) technique by collision-induced
dissociation on a Bruker Apex-4 (Tesla) instrument (Bremen, Germany). The samples were dissolved
in acetonitrile, diluted in spray solution (methanol/water 1:1 v/v  0.1 formic acid) and infused using a
syringe pump with a flow rate of 2 µL/min. external calibration was conducted using the arginine
cluster in a mass range m/z 175-871. Infrared spectra were recorded using a Shimadzu IRAffinity-1
spectrophotometer. The samples were dissolved in CHCl3 and analyzed as thin solid films using NaCl
plates. Analytical thin layer chromatography (TLC) was carried out using pre-coated aluminum plates
and visualized by UV light (λ = 254 and/or 360 nm). Elemental analysis was performed using
EuroVector elemental analyzer (Milan, Italy). All starting materials were purchased from
Sigma-Aldrcih (St. Louis, MO, USA) and used without further purification. Experiments were
performed in purified solvents.
N-(2-Benzoylphenyl)-5-fluoro-1H-indole-2-carboxamide (1). Ethyl-5-fluoroindole-2-carboxylate (6,
1.6 g, 7.6 mmol) was treated with 2-aminobenzophenone (7, 0.5 g, 2.5 mmol) in the presence of
sodium ethoxide (0.17 g, 2.5 mmol) and dimethylformamide (DMF, 10 mL). The mixture was refluxed
for 24 h at 160 ºC and then filtered. DMF was removed by evaporation under reduced pressure and the
residue was purified by column chromatography using cyclohexane/ethyl acetate (85:15) as eluent to
afford the title compound as a yellow solid (0.2 g, 11.6%). m.p. 237–238 ºC. Rf = 0.82 (CHCl3/MeOH,
1
96:4). H-NMR (CDCl3): δ ppm 12.18 (br s, 1H, NHCO), 9.43 (br s, 1H, H-1 indole), 8.86 (d,
J = 8.4 Hz, 1H, H-3 indole), 7.52-7.76 (m, 5H), 7.26-7.37 (m, 4H), 7.07-7.16 (m, 3H); 13C-NMR
(CDCl3): δ ppm 199.49, 158.82, 139.88, 137.75, 133.77, 133.31, 132.32, 131.66, 131.47, 128.79,
127.98, 127.39, 121.61, 121.27, 120.07, 113.19, 112.83, 111.87, 111.74, 105.79, 105.48, 102.97,
102.89; IR (thin film): ν cm-1 3298.28, 2962.66, 1666.50, 1535.34, 1446.61, 1261.45, 1095.57,
1022.27, 798.53; MS (ESI, positive mode): m/z [M+H]+ 359.11903 (C22H16FN2O2 requires 359.11958);
Anal. Calcd for C22H15FN2O2: C, 73.73; H, 4.22; N, 7.82. Found: C, 73.65; H, 4.18, N, 7.91.
N-(3-Benzoylphenyl)-5-fluoro-1H-indole-2-carboxamide (2). Ethyl-5-fluoroindole-2-carboxylate (6)
(1.0 g, 4.8 mmol) was treated with 3-aminobenzophenone (8, 2.86 g, 14.4 mmol) in the presence of
sodium ethoxide (0.33 g, 4.8 mmol) and dimethylsulfoxide (DMSO, 10 mL). The mixture of reaction
was refluxed for 30 h at 190 ºC and then filtered. DMSO was removed by evaporation under reduced
pressure and the residue was purified by column chromatography using cyclohexane/ethyl acetate
(80:20) as eluent to afford the title compound as a yellow solid (0.1 g, 6%): m.p. 249–250 ºC. Rf = 0.83
1
(CHCl3/MeOH, 94:6). H-NMR (CDCl3): δ ppm 10.2 (br s, 1H, NHCO), 9.23 (br s, 1H, H-1 indole),
13
8.21 (s, 1H, H-3 indole), 7.9-8.1 (m, 3H), 7.7-7.8 (m, 4H), 7.5-7.6 (m, 3H), 7.05 (m, 2H); C-NMR
(CDCl3): δ ppm 193.9, 166.5, 139.66, 137.85, 134.73, 136.52, 136.32, 132.28, 131.60, 130.54, 130.21,

Molecules 2010, 15
5846
129.42, 124.56, 121.13, 127.04,122.0, 113.14, 112.78, 111.66, 111.21, 105.49, 104.78; IR (thin film):
ν cm-1 3360.0, 3290.56, 1643.35, 1589.34, 1546.91, 1435.04, 1284.59, 1215.15, 850.25, 803.39; MS
(ESI, positive mode): m/z [M+H]+ 359.11903 (C22H16FN2O2 requires 359.11958); Anal. Calcd for
C22H15FN2O2: C, 73.73; H, 4.22; N, 7.82. Found: C, 73.65; H, 4.18, N, 7.91.
N-(4-Benzoylphenyl)-5-fluoro-1H-indole-2-carboxamide (3). Ethyl-5-fluoroindole-2-carboxylate (6)
(1.0 g, 4.8 mmol) was treated with 4-aminobenzophenone (9, 2.86 g, 14.4 mmol) in the presence of
sodium ethoxide (0.33 g, 4.8 mmol) and DMSO (10 mL). The mixture of reaction was refluxed for 6 h
at 190 ºC and then filtered. DMSO was removed by evaporation under reduced pressure and the
residue was purified by column chromatography using cyclohexane/ethyl acetate (80:20) as eluent to
afford the title compound as a yellow solid (0.65 g, 37.5%). m.p. 249–250 ºC. Rf = 0.67
(CHCl3/MeOH, 94:6). 1H-NMR (CDCl3): δ ppm 12.33 (br s, 1H, NHCO), 9.25 (br s, 1H, H-1 indole),
8.0 (s, 1H, H-3 indole), 7.75-7.86 (m, 4H), 7.3-7.6 (m, 5H), 7.0-7.18 ppm (m, 3H); 13C-NMR (CDCl3):
δ ppm 190.5,157.62, 140.32, 136.75, 133.73, 132.81, 132.32, 131.66, 131.47, 128.36, 127.08, 126.39,
121.81, 121.22, 120.47, 113.0, 112.63, 111.93, 110.89, 105.23, 104.88, 102.54; IR (thin film): ν cm-1
3298.28, 2962.66, 1666.50, 1535.34, 1446.61, 1261.45, 1095.57, 1022.27, 798.53; MS (ESI, positive
mode): m/z [M+H]+ 359.11903 (C22H16FN2O2 requires 359.11958); Anal. Calcd for C22H15FN2O2: C,
73.73; H, 4.22; N, 7.82. Found: C, 73.80; H, 4.27, N, 7.74.
5-Fluoro-N-[2-(4-methylbenzoyl)phenyl]-1H-indole-2-carboxamide
(4).
Ethyl-5-fluoroindole-2-
carboxylate (6, 0.33 g, 1.5 mmol) was treated with 2-aminobenzoyl-2-benzoic acid (10, 0.94 g,
4.5 mmol) in the presence of sodium ethoxide (0.1 g, 1.5 mmol) and DMF (3 mL). The mixture of
reaction was refluxed for 20 h at 150 ºC and then filtered. DMF was removed by evaporation under
reduced pressure and the residue was purified by column chromatography using
cyclohexane/ethylacetate (85:15) as eluent to afford the title compound as a yellow solid (0.065 g,
1
10%). m.p. 233–234 ºC. Rf = 0.77 (CHCl3/MeOH, 94:6). H-NMR (CDCl3): δ ppm 12.1 (br s, 1H,
NHCO), 9.4 (br s, 1H, H-1 indole), 8.85 (d, J = 7.8 Hz, 1H, H-3 indole), 7.6-7.7 (m, 4H), 7.25-7.41
13
(m, 5H), 7.06-7.16 (m, 2H), 2.46 (s, 3H); C-NMR (CDCl3): δ ppm 199.1, 158.75, 142.45, 139.62,
134.97, 133.44, 133.06, 132.28, 131.69, 129.12, 128.06, 127.13, 127.04,122.0, 113.14, 112.78, 111.83,
111.71, 105.79, 105.48, 102.91, 102.83, 20.65; IR (thin film): ν cm-1 3313.71, 2962.66, 1670.35,
1581.63, 1535.34, 1446.61, 1261.45, 1095.57, 1022.27, 803.39; MS (ESI, positive mode): m/z [M+H]+
373.13468 (C23H18FN2O2 requires 373.13523); Anal. Calcd for C23H17FN2O2: C, 74.18; H, 4.60; N,
7.52. Found: C, 74.24; H, 4.66, N, 7.43.
N-[2-Benzoyl-4-chlorophenyl]-5-fluoro-1H-indole-2-carboxamide
(5).
Ethyl-5-fluoroindole-2-
carboxylate (6, 1.0 g, 4.8 mmol) was treated with 2-amino-5-chlorobenzophenone (11, 3.35 g,
14.4 mmol) in the presence of sodium ethoxide (0.33 g, 4.8 mmol) and DMSO (8 mL). The mixture of
reaction was refluxed at 190 ºC for 50 h and then filtered. DMSO was removed by evaporation under
reduced pressure and the residue was purified by column chromatography using
cyclohexane/ethylacetate (90:10) as eluent to afford the title compound as a yellow solid (0.10 g,
1
5.3%). m.p. 202–203 ºC. Rf = 0.86 (CHCl3/MeOH, 96:4). H-NMR (DMSO-d6): δ ppm 11.87 (br s,
1H, NHCO), 10.8 (br s, 1H, H-1 indole), 7.76-7.84 (m, 4H), 7.4-7.67 (m, 6H), 7.22 (s, 1H), 7.11 (m,
1H); 13C-NMR (CDCl3): δ ppm 194.34, 159.93, 137.18, 135.64, 134.29,133.58, 133.49, 132.88, 132.3,

Molecules 2010, 15
5847
130.48, 130.03,129.12, 129.0, 126.71, 115.64, 115.12, 114.03, 113.71, 107.0, 106.48, 105.01, 104.89;
IR (thin film): ν cm-1 3448.72, 3059.10, 2962.66, 1620.21, 1465.90, 1307.74, 1257.59,1099.43,
1026.13, 794.97; MS (ESI, positive mode): m/z [M+H]+ 393.08006 (C23H15ClFN2O2 requires
393.08061); Anal. Calcd for C23H14ClFN2O2: C, 67.27; H, 3.95; N, 7.13. Found: C, 67.20; H, 3.89, N, 7.19.
3.2. Animals and Treatments
Forty eight adult male Wistar rats of two months of age, weighing around 180 g, bred in the animal
care centre of Faculty of Pharmacy, Al-Zaytoonah University, Amman, Jordan, were provided ad
libitum access only to tap water throughout the experiments. Rats were maintained in a 12 h light-dark
cycle under constant humidity and (22 ± 2 ºC). All experiments were performed in accordance with the
Guidelines for Animal Welfare Committee of Al-Zaytoonah University.
3.3. Triton model of Hyperlipidemia
Triton WR-1339 was dissolved in (DMSO) and administered intraperitoneally to the rats
(300 mg/kg body weight) in order to induce hyperlipidemia.
3.4. Pharmacological Experimental Design
Overnight fasted rats were randomly divided into six groups of eight animals each. The first group,
serving as control group (CG) received an intraperitoneal administration of normal saline; the second
hyperlipidemic group (HG) received an intraperitoneal injection of Triton 4% DMSO (in distilled
water). In the third group compound 1 was intraperitoneally injected with Triton, followed by an
intragastric administration of compound 1 (15 mg/kg body weight) dissolved in 4% DMSO; in the rats
of the fourth group compound 2 were also intraperitoneally injected with Triton, followed by an
intragastric administration of compound 2 (15 mg/kg body weight) dissolved in 4% DMSO. In the
fifth group compound 3 were intraperitoneally injected with Triton, followed by an intragastric
administration of compound 3 (15 mg/kg body weight) dissolved in 4% DMSO.The last group (BF)
was also intraperitoneally injected with Triton and intragastrically treated with bezafibrate (100 mg/kg
body weight) dissolved in 4% DMSO. After 12 h of treatments, animals were anaesthetized with
diethyl ether and blood was collected. The blood samples were immediately centrifuged (3,000 rpm for
10 min) and the plasma was used for lipid analysis by an enzymatic method with an automatic
analyzer (Model Erba XL-300, Germany, Mannheim, Germany).
3.5. Statistical Analysis
Results were expressed as mean values and standard deviations. Data obtained were analyzed using
the Student’s t-test, and differences with p < 0.05 were considered statistically significant.
4. Conclusions
In conclusion, 5-fluoro-1H-indole-2-carboxamide derivatives 2 and 3 improved the lipid profile in
Triton-induced hyperlipidemic rats. The results of this study are highly promising, but further studies

Molecules 2010, 15
5848
are required to elucidate the exact mechanism of action as lipid-lowering agents of these
novel compounds.
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Sample Availability: Samples of the compounds are available from the authors.
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