Design, parallel synthesis and SAR of novel urotensin II receptor agonists

Article abstract of DOI:10.1016/j.ejmech.2006.09.015

A 30-membered library of amides based on the potent urotensin II (UII) receptor agonist FL104, has been synthesized from ten different carboxylic acids and three amines. A synthetic protocol producing the amides in 47-98% yield has been developed in which

Full text of DOI:10.1016/j.ejmech.2006.09.015

European Journal of Medicinal Chemistry 42 (2007) 276e285
http://www.elsevier.com/locate/ejmech
Laboratory note
Design, parallel synthesis and SAR of novel urotensin II
receptor agonists
Fredrik Lehmann a, Lisa Lake a, Erika A. Currier c, Roger Olsson b,
Uli Hacksell c, Kristina Luthman a,
*
a Department of Chemistry, Medicinal Chemistry, Go¨teborg University, Kemivagen 10, SE-412 96 Go¨teborg, Sweden
b ACADIA Pharmaceuticals AB, Medeon Science Park, SE-205 12 Malmo¨, Sweden
c ACADIA Pharmaceuticals Inc., 3911 Sorrento Valley Boulevard, San Diego, CA 92121, USA
Received 28 April 2006; received in revised form 17 August 2006; accepted 7 September 2006
Available online 15 November 2006
Abstract
A 30-membered library of amides based on the potent urotensin II (UII) receptor agonist FL104, has been synthesized from ten different
carboxylic acids and three amines. A synthetic protocol producing the amides in 47e98% yield has been developed in which the purification
involved only extractions and in a few cases filtration through an ion-exchange resin. It was found that 5 mg of starting material was enough to
obtain reproducible results and excellent purities. Thus, the procedure is estimated to be transferable to fully automated systems. The synthesized
compounds were evaluated for their UII receptor agonistic activities using a cell-based assay (R-SAT). The most active compounds were the 4-
trifluoromethylcinnamic amides of 1-(4-chlorophenyl)-3-dimethylamino-propylamine and 1-(2-naphthyl)-3-dimethylamino-propylamine, both
showed EC50 values of 130 nM.
Ó 2006 Elsevier Masson SAS. All rights reserved.
Keywords: Urotensin II; Library synthesis; Solid supported reagents; Amidation; Structureeactivity relationships
1. Introduction
this study we have therefore set out to find an efficient syn-
thetic protocol to produce such compounds, ideally without
the need for tedious workup. Thus, solid-supported coupling
reagents (PSeDCC and PSeDMAP) have been used in
combination with excess of the carboxylic acids to drive the
reactions to completion, enabling the synthesis of a 30-
membered library in moderate to excellent yields (47e98%)
of the individual compounds using an easy purification
protocol.
Our interest in UII receptor agonists is based on the poten-
tial role of UII in numerous diseases including hypertension
[2], heart failure [3], atherosclerosis [4], renal failure [5],
and diabetes [6,7]. Although there are some examples of
non-peptidergic antagonists [8aec] and agonists [1,9] in the
literature there is a strong need for potent and selective low
molecular weight ligands to further examine the biology/
pharmacology of the UII system [10]. Therefore, the identifi-
cation, design, and development of such compounds represent
a rapidly emerging research field.
We have recently reported on the structureeactivity rela-
tionships (SAR) in a series of nonpeptidic urotensin II (UII)
receptor agonists leading to the discovery of FL104 (Fig. 1),
the most potent UII agonist reported to date [1].
We then also reported the facile and convenient synthesis of
series of benzamide derivatives from benzoic acids and amine
A (Scheme 1) using thionyl chloride to initially produce the
acid chloride to which A was added.
However, when using the same protocol in the synthesis of
the corresponding 2-phenylacetamide derivative, the workup
procedure became more complicated and involved flash chro-
matography [1]. This limited the usefulness of this procedure
when synthesizing larger series of non-aromatic amides. In
* Corresponding author. Tel.: þ46 31 772 2894; fax: þ46 31 772 3840.
E-mail address: luthman@chem.gu.se (K. Luthman).
0223-5234/$ - see front matter Ó 2006 Elsevier Masson SAS. All rights reserved.
doi:10.1016/j.ejmech.2006.09.015

F. Lehmann et al. / European Journal of Medicinal Chemistry 42 (2007) 276e285
277
O
2. Chemistry
NH
2.1. Synthesis of amines
N
The starting amines AeC were synthesized according to
Scheme 2. The Mannich bases 1aec and amine A were pro-
duced as reported earlier [11]. These amines were chosen to
produce derivatives with electron withdrawing ( p-Cl), electron
donating ( p-Me) and sterically demanding (naphthyl) substit-
uents, respectively.
Cl
Fig. 1. FL104, the most potent UII-agonist reported to date.
The conversion of the ketones to the primary amines was
accomplished according to our previously published procedure
[1]. First the ketones were reduced to alcohols (2aec) using
LiAlH4 in THF in good yields (>90%). Conversion of the al-
cohols to their corresponding acetamide derivatives via a Ritter
reaction [12] using acetonitrile as the nitrogen source, and sub-
sequent hydrolysis in refluxing 6 M HCl afforded the primary
amines (BeC) in moderate to good yields (47e76% over two
steps). Interestingly, the Ritter reaction only worked for liquid
nitriles. Any attempt to perform this reaction directly on a solid
nitrile (e.g. 4-phenyl-benzonitrile) or by first dissolving
the nitrile in an inert solvent such as toluene only resulted in
the conversion of the nitrile to its corresponding primary
amide.
the non-conjugated acids (Table 1). However, for the cinnamic
and propiolic acid derivatives an additional purification step
involving filtration through an ion-exchange resin was some-
times needed.
2.3. Miniaturizing
To check the robustness of the method and to enable the
production of larger libraries we also scaled down linearly
from 50 mg to 25 mg and to 5 mg of the starting amine . As
seen in Table 2, this was accomplished without problems as
both the yields and purities were in the same range as for
the 50 mg reactions.
3. Pharmacological testing
2.2. Synthesis of amides
Compounds A1eC10 were tested for their agonistic prop-
erties at human UII receptors using the functional R-SATÔ as-
say as previously described [14e18].3 The results are shown in
Table 3. For control of the UII receptor selectivity all com-
pounds were tested against the m3 receptor as a negative
control.
In order to examine both the SAR of the aromatic rings and
also the reactivity in the amidation reaction, the carboxylic
acids were chosen to include electron withdrawing (4-CF3)
and electron donating (4-OMe) substituents. We also wanted
to examine both aliphatic acids (2-phenylacetic acids 1e3
and 3-phenylpropionic acids 4e6) as well as conjugated acids
(cinnamic acids 7e9 and propiolic acid 10) to investigate if
any differences in reactivity were observed.
4. Structureeactivity relationships
The amines were dissolved in dichloromethane and 5 equiv
of carboxylic acid,1 2 equiv of PSeDCC and 0.2 equiv of PSe
DMAP were added. The reaction mixtures were shaken for
four days at room temperature (Scheme 3).2
We have previously reported the SAR around benzamide
derivatives involving amine A [1]. We then found that the in-
troduction of a phenyl ring in the 40-position of FL87 remark-
ably enhanced the activity as compared to smaller substituents.
Dichloromethane was selected as solvent due to its higher
density compared to water, thus making small-scale parallel
extractions easier. After completion of the reaction, the resins
were filtered off and the organic phase was washed twice with
1 M sodium hydroxide and once each with water and brine.
This purification procedure was sufficient to provide pure am-
O
4´
NH
N
1
ides (>99% purity according to H NMR spectroscopy) from
FL87
Cl
To investigate if substituents other than a 40-phenyl group
were acceptable for UII receptor interaction we used computer
based conformational analysis (Macromodel, MM3) to iden-
tify derivatives that stretched longer in space than a benzamide,
but shorter than a biphenyl derivative. As seen in Fig. 2, the
1
In an optimization study different ratios of acid to amine were investigated.
When using 1 or 2 equiv the reaction did not go to completion even after one
week, making the purification troublesome. It was found that 5 equiv of acid
was enough to drive the reaction to completion within four days.
2
To shorten the reaction times, we also tried to run this reaction using mi-
crowave heating. After filtration of the resins, however, only the starting car-
boxylic acid was detected. An explanation for this could be that under these
conditions the amine reacts preferentially with the resin, e.g. with PSeDCC,
to form a guanidine, which has been observed earlier [13].
3
The EC50 value for UII in the R-SAT assay was found to be 1.1 ꢀ 10ꢁ11 M.
This could be compared to values obtained from a rat aorta bioassay and
FLIPR experiments on cells expressing the recombinant UT receptor [19e20].

278
F. Lehmann et al. / European Journal of Medicinal Chemistry 42 (2007) 276e285
O
O
O
NH2
R
NH2
O
NH
R2
NH
OH
N
i
+
R
N
R1
+
N
R2
1- 10
OH
A
Cl
R1
{A1 - C10}
N
Cl
A- C
Reagents and conditions: SOCl2, 1.1 eqv, NEt3, 2.2 eqv, THF 0.5 h.
Yields: 60 - 95%
i) PS-DCC 2 eqv, PS-DMAP 0.2 eqv, CH2Cl2, rt, 96h, 46 - 98%
Scheme 1.
Scheme 3.
cinnamic (white) and the propiolic (yellow) amide derivatives
fitted these criteria perfectly. On the other hand, to further ex-
amine the most favourable direction of the aromatic ring, we
also envisioned that the 2-phenylacetic and 3-phenylpropionic
amide derivatives would be considerably more flexible, thus
being able to pick up binding interactions not accessible for
the conjugated systems.
(A4) < cinnamic (A7) z 2-propiolic acid (A10). This could
also be expressed as in Fig. 5, where it is shown that the con-
jugated amides have both higher potencies and efficacies as
compared to the aliphatic derivatives.
In contrast to our previous study [1] the two most potent
compounds in this series (A8 and C8) were also among the
most efficacious ones.
In contrast to our previous study where the aromatic ring of
the amine moiety was kept constant (4-Cl-phenyl) we choose
here to include both an electron donating (4-Me) as well as
a sterically demanding (2-naphthyl) aromatic system to ex-
plore the SAR also in this part of the molecule.
As is apparent from Fig. 3, the A and C series showed
higher potencies than the corresponding B derivatives in all
examples except when using acid 3 (2-(4-methoxyphenyl)ace-
tic acid). These results indicate that an electron deficient 4-
Cl-phenyl or a sterically demanding 2-naphthyl system is more
beneficial than an electron rich 4-Me-phenyl system. Another
trend visible in Fig. 3 is that the 4-CF3-phenyl substituent (in
2, 5 and 8) is more favourable for potency than phenyl (1, 4
and 7) or 4-OMe-phenyl (3, 6 and 9) substitution in the differ-
ent series (AeC).
5. Conclusion
We have developed a highly efficient protocol for the pro-
duction of large libraries of aliphatic and conjugated amides.
The aliphatic amides required only one extraction to provide
pure products, whereas the conjugated amides sometimes
needed a filtration through an ion-exchange resin. The purifi-
cation procedures used are easily transferable to fully auto-
mated systems. A thirty-membered test library revealed
novel information regarding the SAR around FL104 and re-
sulted in potent and efficacious compounds. It was shown
that 13 compounds had EC50 values between 130e870 nM,
but none was more active than FL104. It was also concluded
that conjugated amides in general were better than aliphatic
amides for activity.
When comparing the amides in the series A1, A4, A7,
and A10, as seen in Fig. 4, the trend is that the potency in-
creases in the order 2-phenylacetic (A1) z 3-phenylpropanoic
6. Experimental procedures
6.1. Chemistry
O
OH
LiAlH4
THF
All commercial chemicals were used without purification,
the solid supported reagents were purchased from Agronaut
Technologies (Hengoed UK) and had loadings from 1.2 to
R
N
R
N
2a R = 4-Cl-phenyl, 91%a
b R = 4-Me-phenyl, 91%
c R = 2-Naphthyl, quant
1a R = 4-Cl-phenyl
b R = 4-Me-phenyl
c R = 2-Naphthyl
1
1.6 mmol/g depending on batch used. H NMR (400 MHz)
and 13C NMR (100 MHz) spectra were recorded in CD3OD
unless otherwise stated using a JEOL JMN-ECP400 instru-
ment. All reactions were monitored by TLC (Merck silica
gel 60 F254) and analyzed under UV (254 nm). Elemental anal-
CH3CN
H2SO4, -15°C
yses were performed at Kolbe Analytishe Laboratorium, Mul-
¨
heim an der Ruhr, Germany. Accurate masses were measured
at Biovitrum using an Agilent MSD-TOF (G1969A) connected
to an Agilent 1100 HPLC system (G1312A, G4061AA,
G1367A, G1316A) with a diode array detector (G1315B).
The instrument is calibrated by Agilent ESeTOF tuning mix
and spectra are acquired in positive electrospray mode.
O
NH2
6M HCl
reflux
NH
R
N
R
N
A R = 4-Cl-phenyl, 99%a
B R = 4-Me-phenyl, 47%
C R = 2-Naphthyl, 76%
a) For details see ref [1].
6.1.1. 3-Dimethylamino-1-(4-methylphenyl)propanol 2b
Ketone 1b (3.6 g, 18.8 mmol) was dissolved in THF
(250 ml). LAH (0.72 g, 18.8 mmol) was added slowly and
Scheme 2.

F. Lehmann et al. / European Journal of Medicinal Chemistry 42 (2007) 276e285
279
Table 1
Results from the synthesis of a thirty-membered amide library
NH
2
NH2
NH2
N
N
N
Cl
A
B
C
COOH
COOH
COOH
COOH
R
R
R
1 R = H
4 R = H
7 R = H
10
2 R = CF3
5 R = CF3
8 R = CF3
3 R = OMe
6 R = OMe
9 R = OMe
Acid
Amine
A
B
C
Extraction
Yield %
Ion exchange
Extraction
Yield %
Ion exchange
Extraction
Yield %
Ion exchange
Purity %
Yield %
Purity %
Purity %
Yield %
Purity %
Purity %
Yield %
Purity %
1
2
3
4
5
6
7
8
9
10
92
96
96
92
83
91
87
97
83
147
100
100
100
100
100
100
85
e
e
e
e
93
98
100
100
100
100
100
100
93
e
e
e
e
e
e
86
e
e
60
e
e
67
88
100
100
100
100
100
100
100
51
e
e
e
e
e
e
93
96
e
79
66
e
e
e
e
e
e
e
e
e
e
e
78
98
e
e
84
94
e
e
e
e
62
e
100
e
132
56
100
e
76
e
e
100
97
100
100
75
200
118
102
59
47
64
100
100
100
68
46
100
100
87
120
e
100
88
76
88
Key: all reactions were run to 100% conversion according to 1H NMR spectroscopy.
Purities were determined by 1H NMR spectroscopy. All yields > 100% are mainly due to remaining carboxylic acid in the sample.
the mixture was stirred for 18 h. NaOH (1 M) (100 ml) was
added dropwise until pH 14. The resulting mixture was ex-
tracted with EtOAc (150 ml þ 100 ml). The organic phases
were combined and washed with water (200 ml) and brine
(200 ml) and concentrated to yield the title product as a yellow
oil (3.3 g, 91%). 1H NMR (CDCl3) d 1.78e1.82 (m, 2H), 2.30
(s, 3H), 2.35 (s, 6H), 2.44e2.50 (m, 1H), 2.62e2.69 (m, 1H),
4.90 (dd, 1H, J ¼ 7.2, 12.0 Hz), 7.15 (d, 2H, J ¼ 7.6 Hz), 7.27
(d, 2H, J ¼ 7.6 Hz). 13C NMR (CDCl3) d 21.4, 34.8, 45.6 (2
C:s), 58.7, 75.9, 125.7 (2 C:s), 129.1 (2 C:s), 136.6, 142.4.
J ¼ 6.8, 7.2 Hz), 7.14 (d, 2H, J ¼ 8.4 Hz), 7.22 (d, 2H,
J ¼ 8.4 Hz). 13C NMR (CDCl3) d 21.3, 36.9, 45.7 (2 C:s),
54.8, 57.4, 126.4 (2 C:s), 129.4 (2 C:s), 136.8, 143.4.
6.1.3. 3-Dimethylamino-1-(2-naphthyl)propanol 2c
Ketone 1c (4.0 g, 17.6 mmol) was dissolved in THF
(250 ml). LAH (0.67 g, 17.6 mmol) was added slowly and
the mixture was stirred for 18 h. NaOH (1 M) (100 ml) was
then added dropwise until pH 14. The resulting mixture was
extracted with EtOAc (150 ml þ 100 ml). The organic phases
were combined and washed with water (200 ml) and brine
(100 ml) and concentrated to yield the title product as a yellow
6.1.2. 3-Dimethylamino-1-(4-methylphenyl)propanamine B
Compound 2b (3.3 g, 17.1 mmol) was dissolved in acetoni-
trile (6 ml) and stirred on an ice-salt bath and H2SO4 (15 ml)
was added slowly. After 18 h NaOH pellets were added until
pH 14. The mixture was extracted with EtOAc (2 ꢀ 150 ml).
The organic phases were combined and washed with water
(200 ml) and brine (200 ml) and concentrated to obtain the
corresponding acetamide as a yellow oil. HCl (6 M) (50 ml)
was then added to the intermediate and the solution was re-
fluxed for three days. H2O (100 ml) and NaOH pellets were
added slowly to the mixture until pH 14. The mixture was ex-
tracted with EtOAc (2 ꢀ 100 ml) and the organic phases were
combined and washed with water (100 ml) and brine (100 ml)
and concentrated to yield the title product as a yellow oil
1
oil (4.1 g, quant). H NMR (CDCl3) d 1.86e2.02 (m, 2H),
2.32e2.42 (m, 1H) 2.38 (s, 6H), 2.54e2.63 (m, 1H), 5.11
(dd, 1H, J ¼ 4.0, 6.1 Hz), 7.40e7.52 (m, 3H), 7.76e7.90 (m,
4H). 13C NMR (CDCl3) d 34.5, 45.4 (2 C:s), 58.4, 75.8,
124.1, 124.3, 125.6, 126.0, 127.7, 128.0, 128.1, 132.8,
133.5, 142.6.
Table 2
Results from miniaturizing experiments
Compound Scale (mg) Yield % Purity % Scale (mg) Yield % Purity %
{A1}
{A7}
25
25
94
83
100
100
5
5
92
97
100
100
Key: all reactions were run to 100% conversion according to 1H NMR spec-
troscopy. Purities were determined by 1H NMR spectroscopy after base
extraction.
1
(1.55 g, 47%). H NMR (CDCl3) d 1.81e1.87 (m, 2H), 2.23
(s, 6H), 2.28e2.36 (m, 2H), 2.32 (s, 3H), 3.96 (dd, 1H,

280
F. Lehmann et al. / European Journal of Medicinal Chemistry 42 (2007) 276e285
Table 3
Results from in vitro testing of urotensin-II receptor activity
NH2
NH2
NH2
N
N
N
Cl
A
B
C
COOH
COOH
COOH
COOH
R
R
R
1 R = H
4 R = H
7 R = H
10
2 R = CF3
5 R = CF3
8 R = CF3
3 R = OMe
6 R = OMe
9 R= OMe
Acid
Amine
A
B
C
Efficacyb
pEC50
Efficacyb
pEC50
Efficacyb
a
a
a
pEC50
1
2
3
4
5
6
7
8
9
10
a
5.73 ꢂ 0.47
6.06 ꢂ 0.23
5.82 ꢂ 0.21
5.78 ꢂ 0.10
5.95 ꢂ 0.31
5.53 ꢂ 0.03
6.37 ꢂ 0.12
6.89 ꢂ 0.06
6.29 ꢂ 0.04
6.40 ꢂ 0.04
76 ꢂ 5
53 ꢂ 7
5.38 ꢂ 0.07
5.95 ꢂ 0.03
5.23 ꢂ 0.05
5.34 ꢂ 0.14
5.64 ꢂ 0.09
5.27 ꢂ 0.02
5.81 ꢂ 0.07
6.36 ꢂ 0.08
5.70 ꢂ 0.08
5.51 ꢂ 0.07
83 ꢂ 11
25 ꢂ 4
62 ꢂ 5
73 ꢂ 9
60 ꢂ 6
67 ꢂ 14
97 ꢂ 6
96 ꢂ 1
79 ꢂ 14
131 ꢂ 0
5.76 ꢂ 0.17
6.24 ꢂ 0.06
NAc
121 ꢂ 31
40 ꢂ 3
65 ꢂ 18
139 ꢂ 5
73 ꢂ 10
101 ꢂ 12
128 ꢂ 10
133 ꢂ 3
99 ꢂ 4
NAc
6.22 ꢂ 0.20
6.43 ꢂ 0.07
5.85 ꢂ 0.11
6.23 ꢂ 0.18
6.87 ꢂ 0
107 ꢂ 22
75 ꢂ 1
113 ꢂ 9
116 ꢂ 3
117 ꢂ 1
106 ꢂ 16
115 ꢂ 14
6.42 ꢂ 0.06
124 ꢂ 6
6.34 ꢂ 0.05
Results were determined in R-SAT assays and are expressed as pEC50, the negative of the log EC50 in molarity. Results are the average ꢂ standard deviations of
2e5 determinations of the EC50 where each compound was tested in eight doses in triplicate.
b
The % efficacy values are normalized to UII at 100%.
NA ¼ no detectable activity.
c
6.1.4. 3-Dimethylamino-1-(2-naphthyl)propanamine C
combined and washed with water (100 ml) and brine (100 ml)
and concentrated to yield the title product as a yellow oil
Compound 2c (4.1 g, 17.6 mmol) was dissolved in acetoni-
trile (6 ml) and stirred on an ice-salt bath and H2SO4 (15 ml)
was added slowly. After 18 h NaOH pellets were added until
pH 14. The mixture was extracted with EtOAc (2 ꢀ 150 ml).
The organic phases were combined and washed with water
(200 ml) and brine (200 ml) and concentrated to obtain the
corresponding acetamide as yellow oil. HCl (6 M) (50 ml)
was then added to the intermediate and the solution was re-
fluxed for three days. H2O (100 ml) and NaOH pellets were
added slowly to the mixture until pH 14. The mixture was ex-
tracted with EtOAc (2 ꢀ 100 ml) and the organic phases were
1
(3.05 g, 76%). H NMR (CDCl3) d 1.88e1.95 (m, 2H), 2.15
(s, 6H), 2.24e2.39 (m, 2H), 4.15 (dd, 1H, J ¼ 6.6, 13.6 Hz),
7.41e7.50 (m, 3H), 7.74e7.77 (m, 1H), 7.79e7.86 (m, 3H).
13C NMR (CDCl3) d 37.1, 45.7 (2 C:s), 55.1, 57.2, 124.8 (2
C:s), 126.1 (2 C:s), 127.7, 127.9, 128.3, 132.8, 133.4, 143.9.
6.1.5. General procedure for the synthesis of amides
The amine(1 equiv, 50 mg), PSeDCC (2 equiv), PSeDMAP
(0.2 equiv), carboxylic acid (5 equiv) and DCM (15 ml) were
added to a vial and shaken at room temperature for four days.
Fig. 2. Alignment of the global minimum conformations of A1 (blue), A4 (red), A7 (white), A10 (yellow) and FL104 (green) identified by conformational analysis
using molecular mechanics calculations (MM3, MacroModel v. 7.0).

F. Lehmann et al. / European Journal of Medicinal Chemistry 42 (2007) 276e285
281
140
120
100
6,7
6,2
5,7
5,2
A
Aliphatic
80
B
Conjugated
60
C
40
20
5,2
5,7
6,2
pEC50
6,7
1
2
3
4
5
6
7
8
9
10
Fig. 5. Scatter plot of the correlation between efficacy and pEC50 values for
aliphatic [A1eC6] (diamonds) and conjugated derivatives [A7eC10]
(squares).
Acid
Fig. 3. Comparisons of the UII-receptor agonist potencies of the synthesized
amides divided into families. The potencies were determined in the cell based
R-SAT assay.
2.79e2.90 (m, 1H), 2.86 (s, 6H), 3.00e3.20 (m, 2H), 3.67
(s, 2H), 4.96 (dd, 1H, J ¼ 6.2, 8.8 Hz), 7.35 (app. s, 4H), 7.48
(d, 2H, J ¼ 8.3 Hz), 7.60 (d, 2H, J ¼ 8.3 Hz). 13C NMR
d 30.5, 41.6, 42.1, 42.4, 51.6, 55.2, 124.4 (q, 1JCF ¼ 269.1 Hz),
The mixture was then filtered and the solute was concentrated.
1H NMR spectra were run to control that the reactions had
gone to completion. The crude product was then dissolved in
CH2Cl2 (20 ml) and washed with 1 M NaOH (2 ꢀ 15 ml). The
3
125.0 (q, 2 C:s, JCF ¼ 3.8 Hz), 128.2 (2 C:s), 128.6 (2 C:s),
2
128.8 (q, JCF ¼ 32.1 Hz), 129.6 (2 C:s), 133.3, 139.8, 140.2,
1
171.5. HRTofMS calcd for C20H22ClF3N2O (Mþ) m/z
CH2Cl2-phase was then concentrated. H NMR spectra were
398.1373, found 398.1378.
run to control the purity. If the product was not pure (>98%
purity) ion exchange chromatography (SCX-2) was used for
the final purification. The pure product was then converted to
the corresponding HCl salt using HCl saturated ether.
6.1.8. N-[1-(4-Chlorophenyl)-3-dimethylamino-propyl]-2-
(4-methoxyphenyl)acetamide HCl {A3}
2-(4-Methoxyphenyl)acetic acid (196 mg, 1.18 mmol)
1
yielded 82 mg {A3} (96%). H NMR d 2.18e2.26 (m, 2H),
6.1.6. N-[1-(4-Chlorophenyl)-3-dimethylamino-propyl]-2-
phenylacetamide HCl {A1}
2-Phenylacetic acid (161 mg, 1.18 mmol) yielded 72 mg
2.83 (app d, 6H, J ¼ 7.3 Hz), 2.99e3.12 (m, 2H), 3.49 (s,
2H), 3.75 (s, 3H), 4.95 (t, 1H, J ¼ 7.3 Hz), 6.85 (d, 2H,
J ¼ 8.4 Hz), 7.20 (d, 2H, J ¼ 8.4 Hz), 7.35 (app. s, 4H). 13C
NMR d 30.4, 41.6, 42.0, 42.6, 50.2, 54.4, 55.1, 113.7 (2
C:s), 127.5, 128.2 (2 C:s), 128.6 (2 C:s), 129.8 (2 C:s),
133.4, 139.5, 158.9, 173.1. HRTofMS calcd for C20H25ClN2O2
(Mþ) m/z 360.1605, found 360.1611.
1
{A1} (92%). H NMR d 2.83e2.92 (m, 2H), 3.29 (s, 6H),
3.72e3.80 (m, 2H), 4.26 (s, 2H), 5.63 (dd, 1H, J ¼ 6.6,
14.6 Hz), 7.97e8.12 (m, 5H), 8.13e8.23 (m, 4H). 13C NMR
d 30.5, 42.2, 42.5 (2 C:s), 50.4, 55.2, 126.7, 128.1 (2 C:s),
128.3 (2 C:s), 128.5 (2 C:s), 128.8 (2 C:s), 133.2, 135.6,
139.8, 172.5. HRTofMS calcd for C19H23ClN2O (Mþ) m/z
330.1499, found 330.1504.
6.1.9. N-[1-(4-Chlorophenyl)-3-dimethylamino-propyl]-3-
phenylpropionamide HCl {A4}
3-Phenylpropionic acid (179 mg, 1.18 mmol) yielded
6.1.7. N-[1-(4-Chlorophenyl)-3-dimethylamino-propyl]-2-
(4-trifluoromethylphenyl)acetamide HCl {A2}
2-(4-Trifluoromethylphenyl)acetic acid(250 mg, 1.18 mmol)
1
75 mg {A4} (92%). H NMR d 2.06e2.20 (m, 2H), 2.50e
2.64 (m, 2H), 2.82 (s, 6H), 2.89e2.94 (m, 2H), 2.94e3.00
(m, 2H), 4.90 (dd, 1H, J ¼ 6.6, 15.0 Hz), 7.16e7.20 (m,
3H), 7.21e7.27 (m, 4H), 7.29e7.34 (m, 2H). 13C NMR
d 14.1, 30.3, 31.3, 37.2, 41.9, 42.7, 65.6, 126.0, 128.1 (2
C:s), 128.2 (2 C:s), 128.3 (2 C:s), 128.5 (2 C:s), 133.2,
139.6, 140.6, 173.6. HRTofMS calcd for C20H25ClN2O
(Mþ) m/z 344.1655, found 344.1659.
1
yielded 90 mg {A2} (96%). H NMR d 2.16e2.30 (m, 1H),
160
140
120
100
A1
A4
A7
A10
80
60
40
20
0
6.1.10. N-[1-(4-Chlorophenyl)-3-dimethylamino-propyl]-3-
(4-trifluoromethylphenyl)propionamide HCl {A5}
3-(4-Trifluoromethylphenyl)propanoic
acid
(256 mg,
1
1.18 mmol) yielded 81 mg {A5} (83%). H NMR d 2.10e
2.18 (m, 2H), 2.52e2.67 (m, 2H), 2.84 (s, 6H), 2.96e3.30
(m, 2H), 3.32e3.40 (m, 2H), 4.92 (dd, 1H, J ¼ 4.8, 7.3 Hz),
7.20e7.26 (m, 2H), 7.32e7.38 (m, 4H), 7.48e7.54 (d, 2H,
J ¼ 8.1 Hz). 13C NMR d 30.0, 31.3, 32.0, 37.5, 43.1, 43.5,
-8
-7
log [ligand] (M)
-6
-5
-4
-20
Fig. 4. UII receptor activity of A1, A4, A7 and A10 in the functional cell based
R-SAT assay.
1
64.8, 126.3 (2 C:s), 128.5 (q, JCF ¼ 271.4 Hz), 128.8 (q,

282
F. Lehmann et al. / European Journal of Medicinal Chemistry 42 (2007) 276e285
2JCF ¼ 29.8 Hz), 129.5 (2 C:s), 129.6 (2 C:s), 130.4 (2 C:s),
132.9, 142.8, 147.4, 172.2. HRTofMS calcd for
C21H24ClF3N2O (Mþ) m/z 412.1529, found 412.1529.
d 30.3, 42.3 (2 C:s), 51.0, 55.1, 82.1, 85.5, 119.9, 128.2 (2
C:s), 128.5 (2 C:s), 128.7 (2 C:s), 130.3, 132.2 (2 C:s),
133.5, 139.2, 153.9. HRTofMS calcd for C20H21ClN2O
(Mþ) m/z 340.1342, found 340.1346.
6.1.11. N-[1-(4-Chlorophenyl)-3-dimethylamino-propyl]-3-
(4-methoxyphenyl)propionamide HCl {A6}
3-(4-Methoxyphenyl)propionic acid (218 mg, 1.21 mmol)
6.1.16. N-[3-Dimethylamino-1-(4-methylphenyl)propyl]-2-
phenylacetamide HCl {B1}
2-Phenylacetic acid (187 mg, 1.32 mmol) yielded 75 mg
1
yielded 80 mg {A6} (91%). H NMR d 2.06e2.16 (m, 2H),
2.47e2.60 (m, 2H), 2.76e2.84 (m, 2H), 2.82 (s, 6H), 2.91e
3.02 (m, 2H), 3.70 (s, 3H), 4.88 (dd, 1H, J ¼ 6.2, 8.8 Hz),
6.78 (d, 2H, J ¼ 8.4 Hz), 7.08 (d, 2H, J ¼ 8.4 Hz), 7.20 (d,
2H, J ¼ 8.4 Hz), 7.30 (d, 2H, J ¼ 8.4 Hz). 13C NMR d 30.4,
30.5, 37.5, 42.0 (2 C:s), 54.3, 55.1, 65.6, 113.6 (2 C:s),
128.0 (2 C:s), 128.5 (2 C:s), 129.3 (2 C:s), 132.5, 133.1,
139.6, 158.3, 173.7. HRTofMS calcd for C21H27ClN2O2
(Mþ) m/z 374.1761, found 360.1770.
1
{B1} (93%). H NMR d 2.00e2.10 (m, 2H), 2.15 (s, 3H),
2.65 (s, 6H), 2.80e3.00 (m, 2H), 3.41 (s, 2H), 4.80 (dd, 1H,
J ¼ 6.8, 9.2 Hz), 7.03 (d, 2H, J ¼ 8.0 Hz), 7.12 (d, 2H,
J ¼ 8.0 Hz), 7.15e7.19 (m, 5H). 13C NMR d 23.9, 34.8,
46.1, 46.6 (2 C:s), 54.7, 59.3, 130.5 (2 C:s), 130.7, 132.4 (2
C:s), 132.9 (2 C:s), 133.2 (2 C:s), 139.8, 141.5, 141.8,
176.6. HRTofMS calcd for C20H26N2O (Mþ) m/z 310.2045,
found 310.2045.
6.1.12. N-[1-(4-Chlorophenyl)-3-dimethylamino-propyl]-3-
cinnamamide HCl {A7}
Cinnamic acid (179 mg, 1.18 mmol) yielded 50 mg {A7}
6.1.17. N-[3-Dimethylamino-1-(4-methylphenyl)propyl]-2-
(4-trifluoromethylphenyl)acetamide HCl {B2}
2-(4-Trifluoromethylphenyl)acetic acid (270 mg, mmol)
1
(62%). H NMR d 2.20e2.38 (m, 2H), 2.80e2.94 (m, 1H),
2.89 (s, 6H), 3.12e3.27 (m, 1H), 5.12 (dd, 1H, J ¼ 5.5,
9.2 Hz), 6.75 (d, 1H, J ¼ 15.8 Hz), 7.30e7.50 (m, 6H),
7.50e7.60 (m, 4H). 13C NMR d 14.1, 30.7, 42.1, 42.5, 65.6,
120.1, 127.6 (2 C:s), 128.2 (2 C:s), 128.7 (4 C:s), 129.7,
133.3, 134.8, 139.8, 141.3, 170.0. HRTofMS calcd for
C20H23ClN2O (Mþ) m/z 342.1499, found 342.1510.
1
yielded 95 mg {B2} (98%). H NMR d 2.00e2.10 (m, 2H),
2.15 (s, 3H), 2.55 (s, 6H), 2.65e2.90 (m, 2H), 3.15 (s, 2H),
4.75 (t, 1H, J ¼ 5.2 Hz), 7.01 (d, 2H, J ¼ 8.0 Hz), 7.15 (d,
2H, J ¼ 8.0 Hz), 7.32 (d, 2H, J ¼ 8.0 Hz), 7.43 (d, 2H,
J ¼ 8.0 Hz). 13C NMR d 19.8, 31.2, 42.1, 42.6 (2 C:s), 51.1,
1
55.4, 124.5 (q, JCF ¼ 270.0 Hz), 125.0 (q,
2
C:s,
2
6.1.13. N-[1-(4-Chlorophenyl)-3-dimethylamino-propyl]-4-
trifluoromethyl-cinnamamide HCl {A8}
4-Trifluoromethyl-cinnamic acid (259 mg, 1.18 mmol)
3JCF ¼ 3.8 Hz), 126.4 (2 C:s), 128.8 (q, JCF ¼ 32.1 Hz),
129.1 (2 C:s), 129.6 (2 C:s), 137.4, 136.0, 140.3, 171.3.
HRTofMS calcd for C21H25F3N2O (Mþ) m/z 378.1919, found
378.1921.
1
yielded 70 mg {A8} (97%). H NMR d 2.20e2.40 (m, 2H),
2.84e2.96 (m, 1H), 2.90 (s, 6H), 3.12e3.28 (m, 1H), 5.11
(dd, 1H, J ¼ 5.2, 13.9 Hz), 6.85 (d, 1H, J ¼ 15.8 Hz), 7.30e
7.47 (m, 4H), 7.60 (d, 1H, J ¼ 15.8 Hz), 7.65e7.71 (m, 2H),
7.72e7.80 (m, 2H). HRTofMS calcd for C21H22ClF3N2O
(Mþ) m/z 410.1373, found 410.1382.
6.1.18. N-[3-Dimethylamino-1-(4-methylphenyl)propyl]-2-
(4-methoxyphenyl)acetamide HCl {B3}
2-(4-Methoxyphenyl)acetic acid (229 mg, 1.38 mmol)
1
yielded 82 mg {B3} (93%). H NMR d 2.03e2.08 (m, 2H),
6.1.14. N-[1-(4-Chlorophenyl)-3-dimethylamino-propyl]-4-
methoxy-cinnamamide HCl {A9}
4-Methoxycinnamic acid (234 mg, 1.31 mmol) yielded
2.13 (s, 3H), 2.65 (app. d, 6H), 2.58e3.00 (m, 2H), 3.35
(app d, 2H, J ¼ 2.4 Hz), 3.75 (s, 3H), 4.80 (dd, 1H, J ¼ 6.4,
6.4 Hz), 6.71 (d, 2H, J ¼ 8.0 Hz), 7.03 (d, 2H, J ¼ 8.0 Hz),
7.06e7.14 (m, 4H). 13C NMR d 23.9, 34.8, 45.7, 46.1, 46.6,
54.7, 58.5, 59.3, 117.7 (2 C:s), 130.4 (2 C:s), 131.7, 133.2
(2 C:s), 133.9 (2 C:s), 141.5, 141.8, 162.9, 177.0. HRTofMS
calcd for C21H28N2O2 (Mþ) m/z 340.2151, found 340.2159.
1
60 mg {A9} (68%). H NMR d 2.20e2.38 (m, 2H), 2.80e
2.98 (m, 1H), 2.90 (s, 6H), 3.10e3.32 (m, 1H), 3.80 (s, 3H),
5.11 (dd, 1H, J ¼ 5.5, 9,2 Hz), 6.60 (d, 1H, J ¼ 15.8 Hz),
6.93 (d, 2H, J ¼ 8.4 Hz), 7.36 (d, 2H, J ¼ 8.4 Hz), 7.43 (d,
2H, J ¼ 8.4 Hz), 7.47e7.58 (m, 3H). 13C NMR d 30.8, 42.1,
42.6, 50.5, 54.6, 55.2, 114.1 (2 C:s), 117.5, 127.4, 128.2 (2
C:s), 128.7 (2 C:s), 129.3 (2 C:s), 133.3, 140.0, 141.1,
161.5, 167.4. HRTofMS calcd for C21H25ClN2O2 (Mþ) m/z
372.1605, found 372.1609.
6.1.19. N-[3-Dimethylamino-1-(4-methylphenyl)propyl]-3-
phenylpropionamide HCl {B4}
3-Phenylpropionic acid (207 mg, 1.37 mmol) yielded
1
81 mg {B4} (96%). H NMR d 1.80e2.17 (m, 2H), 2.30 (s,
6.1.15. N-[1-(4-Chlorophenyl)-3-dimethylamino-propyl]-3-
phenylpropiolamide HCl {A10}
3-Phenylpropiolic acid (172 mg, 1.19 mmol) yielded 40 mg
3H), 2.50e2.64 (m, 2H), 2.80 (s, 6H), 2.85e2.98 (m, 4H),
4.84 (dd, 1H, J ¼ 8.08, 8.08 Hz), 7.10e7.26 (m, 9H). 13C
NMR d 19.8, 30.6, 31.4, 37.2, 42.6, 47.1, 51.0, 55.2, 126.0,
126.3 (2 C:s), 128.2 (2 C:s), 128.3 (2 C:s), 129.1 (2 C:s),
137.3, 137.8, 140.7, 173.5. HRTofMS calcd for C21H28N2O
(Mþ) m/z 324.2202, found 324.2214.
1
{A10} (50%). H NMR d 2.20e2.36 (m, 2H), 2.84e2.94 (m,
2H), 2.90 (s, 6H), 5.07 (dd, 1H, J ¼ 5.5, 8.8 Hz), 7.36e7.44
(m, 6H), 7.45e7.50 (m, 1H), 7.54e7.60 (m, 2H). 13C NMR

F. Lehmann et al. / European Journal of Medicinal Chemistry 42 (2007) 276e285
283
6.1.20. N-[3-Dimethylamino-1-(4-methylphenyl)propyl]-3-
(4-trifluoromethylphenyl)propionamide HCl {B5}
J ¼ 8.8 Hz), 7.19 (d, 2H, J ¼ 8.0 Hz), 7.30 (d, 2H,
J ¼ 8.0 Hz), 7.46e7.49 (m, 3H). 13C NMR d 19.8, 31.0,
42.0, 42.6, 50.7, 54.6, 55.3, 114.0 (2 C:s), 117.6, 126.4 (2
C:s), 127.4, 129.2 (2 C:s), 129.3 (2 C:s), 130.0, 137.5,
140.9, 161.4, 167.2. HRTofMS calcd for C22H28N2O2 (Mþ)
m/z 352.2151, found 352.2152.
3-(4-Trifluoromethylphenyl)propionic
acid
(284 mg,
1
1.32 mmol) yielded 80 mg {B5} (78%). H NMR d 1.88e
1.96 (m, 2H), 2.30 (s, 3H), 2.50e2.66 (m, 4H), 2.82 (s, 6H),
2.94e3.02 (m, 2H), 4.80 (t, 1H, J ¼ 5.3 Hz),7.04 (d, 2H,
J ¼ 8.4 Hz), 7.34 (d, 2H, J ¼ 8.4 Hz), 7.44e7.50 (m, 4H).
13C NMR d 19.8, 30.6, 31.1, 36.9 (2 C:s), 42.1, 42.6, 52.5,
6.1.25. N-[3-Dimethylamino-1-(4-methylphenyl)propyl]-3-
phenylpropiolamide {B10}
3-Phenylpropiolic acid (193 mg, 1.32 mmol) yielded 50 mg
3
125.0 (2 C:s), 126.3 (q, 2 C:s, JCF ¼ 9.2 Hz), 127.0 (q,
2
1JCF ¼ 280 Hz), 128.4 (q, JCF ¼ 33.1 Hz), 128.9 (2 C:s),
1
129.1 (2 C:s), 137.3, 137.9, 145.4, 173.0. HRTofMS calcd
for C22H27F3N2O (Mþ) m/z 392.4685, found 392.4683.
{B10} (60%). H NMR d 2.10e2.40 (m, 2H), 2.25 (s, 3H),
2.80 (s, 6H), 3.00e3.20 (m, 2H), 5.00 (dd, 1H, J ¼ 6.2,
8.1 Hz), 7.17 (d, 2H, J ¼ 8.0 Hz), 7.27 (d, 2H, J ¼ 8.0 Hz),
7.32e7.50 (m, 3H), 7.50e7.60 (m, 2H). 13C NMR d 19.8,
30.5, 41.0 (2 C:s), 51.2, 55.2, 81.0, 82.5, 120.0, 126.4 (2
C:s), 128.5 (2 C:s), 129.2 (2 C:s), 130.2, 132.2 (2 C:s),
137.0, 137.5, 154.0. HRTofMS calcd for C21H24N2O (Mþ)
m/z 320.1889, found 320.1887.
6.1.21. N-[3-Dimethylamino-1-(4-methylphenyl)propyl]-3-
(4-methoxyphenyl)propionamide HCl {B6}
3-(4-Methoxyphenyl)propionic acid (236 mg, 1.31 mmol)
1
yielded 90 mg {B6} (98%). H NMR d 1.95e2.05 (m, 2H),
2.08 (s, 3H), 2.32e2.48 (m, 2H), 2.67 (s, 6H), 2.68e2.86
(m, 4H), 3.60 (s, 3H), 4.75 (t, 1H, J ¼ 9.6 Hz), 6.65 (d, 2H,
J ¼ 8.8 Hz), 6.97 (d, 2H, J ¼ 8.8 Hz), 6.98e7.40 (m, 4H).
13C NMR d 23.9, 34.7 (2 C:s), 41.6, 46.0, 46.7, 54.4, 58.4,
59.3, 117.6 (2 C:s), 130.4 (2 C:s), 133.1 (2 C:s), 133.3 (2
C:s), 136.6, 141.3, 141.8, 162.3, 177.7. HRTofMS calcd for
C22H30N2O2 (Mþ) m/z 354.2307, found 354.2306.
6.1.26. N-[3-Dimethylamino-1-(2-naphthyl)propyl]-2-
phenylacetamide HCl {C1}
2-Phenylacetic acid (148 mg, 1.18 mmol) yielded 51 mg
1
{C1} (67%). H NMR d 2.26e2.40 (m, 2H), 2.82 (s, 6H),
3.00e3.20 (m, 2H), 3.59 (s, 2H), 5.14 (dd, 1H, J ¼ 6.2,
8.8 Hz), 7.20e7.36 (m, 5H), 7.43e7.53 (m, 3H), 7.78e7.91
(m, 4H). 13C NMR d 30.5, 42.1, 42.5 (2 C:s), 51.0, 54.9,
124.4, 125.2, 125.9, 126.2, 126.7, 127.3, 127.6, 128.3 (2
C:s), 128.5, 128.8 (2 C:s), 132.8, 133.2, 135.4, 137.8, 172.6.
Anal. Calcd. for C23H27ClN2O ꢀ H2O: C, 68.9; H, 7.3; N,
7.0. Found: C, 68.8; H, 7.3; N, 6.7.
6.1.22. N-[3-Dimethylamino-1-(4-methylphenyl)propyl]
cinnamamide {B7}
Cinnamic acid (198 mg, 1.34 mmol) yielded 72 mg {B7}
1
(86%). H NMR d 2.20e2.38 (m, 2H) 2.30 (s, 3H), 2.78e
2.94 (m, 1H) 2.86 (s, 6H), 3.28e3.32 (m, 1H), 5.07 (dd, 1H,
J ¼ 8.8, 14.6 Hz), 6.73 (d, 1H, J ¼ 16.8 Hz), 7.14 (d, 2H,
J ¼ 7.7 Hz), 7.23e7.42 (m, 5H), 7.46e7.60 (m, 3H). 13C
NMR d 19.8, 30.9, 42.1 (2 C:s), 50.9, 55.3, 120.3, 126.5 (2
C:s), 127.6 (2 C:s), 128.7 (2 C:s), 129.2 (2 C:s), 129.7,
134.9, 137.6, 137.8, 141.1, 166.9. HRTofMS calcd for
C21H26N2O (Mþ) m/z 322.2045, found 322.2055.
6.1.27. N-[3-Dimethylamino-1-(2-naphthyl)propyl]-2-
(4-trifluoromethylphenyl)acetamide HCl {C2}
2(4-Trifluoromethylphenyl)acetic acid (223 mg, 1.18 mmol)
1
yielded 80 mg {C2} (88%). H NMR d 2.30e2.40 (m, 2H),
2.85 (s, 6H), 3.02e3.22 (m, 2H), 3.70 (s, 2H), 5.14 (dd, 1H,
J ¼ 7.3, 15.0 Hz), 7.42e7.54 (m, 5H), 7.56e7.64 (d, 2H,
J ¼ 8.0 Hz), 7.76e7.92 (m, 4H). 13C NMR d 30.5, 41.8,
6.1.23. N-[3-Dimethylamino-1-(4-methylphenyl)propyl]-4-
trifluoromethyl-cinnamamide HCl {B8}
4-Trifluoromethyl-cinnamic acid (286 mg, mmol) yielded
1
42.1, 42.5, 51.2, 55.0, 124.2 (q, JCF ¼ 269.1 Hz), 124.4,
3
125 (q, 2 C:s, JCF ¼ 3.8 Hz), 125.2, 126.0, 126.2, 127.4,
1
2
60 mg {B8} (56%). H NMR d 1.90e2.08 (m, 2H), 2.20 (s,
127.6, 128.5, 128.8 (q, JCF ¼ 32.1 Hz), 129.6 (2 C:s),
6H), 2.30 (s, 3H), 3.28e3.34 (m, 2H), 4.96e5.02 (dd, 1H,
J ¼ 7.3, 15.0 Hz), 6.78 (d, 1H, J ¼ 15.8 Hz), 7.14 (d, 2H,
J ¼ 8.0 Hz), 7.22 (d, 2H, J ¼ 8.0 Hz), 7.54 (d, 1H, J ¼
15.8 Hz), 7.65 (d, 2H, J ¼ 8.0 Hz), 7.72 (d, 2H, J ¼ 8.0 Hz).
13C NMR d 19.8, 33.6, 44.2 (2 C:s), 52.0, 56.4, 123.5, 125.5
133.1, 133.4, 137.9, 140.2, 171.6. Anal. Calcd. for
C24H26ClF3N2O ꢀ H2O: C, 61.5; H, 6.0; N, 6.0. Found: C,
61.7; H, 6.0; N, 5.6.
6.1.28. N-[3-Dimethylamino-1-(2-naphthyl)propyl]-2-
(4-methoxyphenyl)acetamide HCl {C3}
2-(4-Methoxyphenyl)acetic acid (182 mg, 1.10 mmol)
3
1
(q, 2 C:s, JCF ¼ 8.8 Hz), 126.3 (2 C:s), 126.5 (q, JCF
¼
2
240 Hz), 128.0 (2 C:s), 128.6 (q, JCF ¼ 30.0 Hz), 128.9 (2
C:s), 136.9, 138.7, 138.9, 139.2, 165.7. HRTofMS calcd for
C22H25F3N2O (Mþ) m/z 390.4526, found 390.4528.
1
yielded 65 mg {C3} (79%). H NMR d 2.05e2.23 (m, 2H),
2.43 (s, 6H), 2.58e2.60 (m, 2H), 3.49 (s, 2H), 3.75 (s, 3H),
5.09 (dd, 1H, J ¼ 6.24, 8.44 Hz), 6.85 (d, 2H, J ¼ 8.8 Hz),
7.22 (d, 2H, J ¼ 8.8 Hz), 7.40e7.49 (m, 3H), 7.77e7.84 (m,
4H). 13C NMR d 32.0, 41.8, 43.3 (2 C:s), 54.4, 55.8, 65.6,
113.7 (2 C:s), 124.4, 124.9, 125.7, 126.0, 127.3, 127.6,
127.7, 128.2, 129.8 (2 C:s), 132.9, 133.5, 138.9, 158.9,
172.8. HRTofMS calcd for C24H28N2O2 (Mþ) m/z 376.2151,
found 376.2165.
6.1.24. N-[3-Dimethylamino-1-(4-methylphenyl)propyl]-4-
methoxy-cinnamamide HCl {B9}
4-Methoxy-cinnamic acid (232 mg, 1.30 mmol) yielded
1
{B9} (87%). H NMR d 2.18e2.39 (m, 2H), 2.30 (s, 3H),
2.85 (s, 6H), 3.08e3.24 (m, 2H), 3.34 (s, 3H), 5.07 (dd, 1H,
J ¼ 6.2, 8.8 Hz), 6.58 (d, 1H, J ¼ 15.8 Hz), 6.92 (d, 2H,

284
F. Lehmann et al. / European Journal of Medicinal Chemistry 42 (2007) 276e285
6.1.29. N-[3-Dimethylamino-1-(2-naphthyl)propyl]-3-
phenylpropionamide HCl {C4}
3-Phenylpropionic acid (164 mg, 1.20 mmol) yielded
6.1.33. N-[3-Dimethylamino-1-(2-naphthyl)propyl]-4-
trifluoromethyl-cinnamamide HCl {C8}
4-Trifluoromethylcinnamic acid (237 mg, 1.20 mmol)
1
1
52 mg {C4} (66%). H NMR d 2.10e2.30 (m, 2H), 2.52e
yielded 55 mg {C8} (59%). H NMR d 2.37e2.50 (m, 2H),
2.68 (m, 2H), 2.83 (s, 6H), 2.93 (t, 2H, J ¼ 7.7 Hz), 2.99 (t,
2H, J ¼ 7.7 Hz), 5.10 (dd, 1H, J ¼ 5.9, 9.5 Hz), 7.10e7.23
(m, 6H), 7.38 (dd, 1H, J ¼ 1.8, 8.8 Hz), 7.45e7.53 (m, 2H),
7.80e7.90 (m, 3H). 13C NMR d 30.4, 31.4, 37.2, 41.9, 42.6,
50.7, 55.4, 124.4, 125.2, 125.9, 126.0, 126.1, 127.3, 127.7,
128.2 (2 C:s), 128.3 (2 C:s), 128.4, 133.0, 133.4, 138.0,
140.7, 173.9. HRTofMS calcd for C24H28N2O (Mþ) m/z
360.2202, found 360.2210.
2.84e2.96 (m, 1H), 2.90 (s, 6H), 3.14e3.22 (m, 1H), 5.30
(dd, 1H, J ¼ 6.6, 14.7 Hz), 6.90 (d, 1H, J ¼ 15.8 Hz), 7.44e
7.53 (m, 2H), 7.54e7.62 (m, 1H), 7.63e7.71 (m, 2H),
7.72e7.79 (m, 3H), 7.82e7.96 (m, 4H). 13C NMR d 30.7,
1
42.4 (2 C:s), 51.2, 55.1, 123.1, 124.2 (q, JCF ¼ 279.1 Hz),
3
124.4, 125.4, 125.5 (q, 2 C:s, JCF ¼ 3.8 Hz), 126.0, 126.2,
2
127.4, 127.7, 128.1 (2 C:s), 128.6, 130.9 (q, JCF ¼ 34.3 Hz),
133.1, 133.5, 138.0, 138.7, 139.3, 166.4. HRTofMS calcd for
C25H25F3N2O (Mþ) m/z 426.1919, found 426.1922.
6.1.34. N-[3-Dimethylamino-1-(2-naphthyl)propyl]-4-
methoxy-cinnamamide HCl {C9}
4-Methoxycinnamic acid (220 mg, 1.23 mmol) yielded
6.1.30. N-[3-Dimethylamino-1-(2-naphthyl)propyl]-2-
(4-trifluoromethylphenyl)propionamide HCl {C5}
3-(4-Trifluoromethylphenyl)propionic
acid
(239 mg,
1
1
40 mg {C9} (47%). H NMR d 2.36e2.45 (m, 2H), 2.85e
1.17 mmol) yielded 79 mg {C5} (84%). H NMR d 2.20e
2.35 (m, 2H), 2.56e2.60 (m, 2H), 2.79e2.80 (m, 1H), 2.84
(s, 6H), 2.96e3.02 (m, 2H), 3.03e3.20 (m, 1H), 5.11 (dd,
1H, J ¼ 7.3, 14.3 Hz), 7.29e7.40 (m, 2H), 7.41e7.54 (m,
4H), 7.74e7.93 (m, 5H). 13C NMR d 30.4, 31.1, 36.7, 42.1,
2.94 (m, 1H), 2.91 (s, 6H), 3.10e3.30 (m, 1H), 3.80 (s, 3H),
5.29 (dd, 1H, J ¼ 7.32, 15.0 Hz), 6.60 (d, 1H, J ¼ 7.0 Hz),
6.88e6.98 (m, 2H), 7.44e7.60 (m, 6H), 7.80e7.96 (m, 4H).
13C NMR d 30.8, 42.0, 42.5, 54.5, 55.3, 88.0, 114.1 (2 C:s),
117.1, 124.1, 125.0, 125.8, 126.0, 127.4 (2 C:s), 127.7,
128.0, 129.3 (2 C:s), 133.0, 133.2, 138.0, 141.0, 161.1,
167.0. HRTofMS calcd for C25H28N2O2 (Mþ) m/z 388.2151,
found 388.2162.
3
42.3, 50.9, 55.3, 124.3, 124.9 (q, 2 C:s, JCF ¼ 3.8 Hz),
1
125.3, 125.9, 126.2, 126.8 (q, JCF ¼ 241.5 Hz), 127.4,
2
127.7, 128.5 (q, JCF ¼ 35.3 Hz), 128.9 (2 C:s), 133.0, 133.4,
138.1, 145.4, 173.2. Anal. Calcd. for C25H28ClF3
N2O$HCl ꢀ H2O: C, 62.2; H, 6.3; N, 5.8. Found: C, 62.3;
H, 6.2; N, 5.6.
6.1.35. N-[3-Dimethylamino-1-(2-naphthyl)propyl]-3-
phenylpropiolamide HCl {C10}
3-Phenylpropiolic acid (161 mg, 1.19 mmol) yielded 50 mg
1
{C10} (64%). H NMR d 2.32e2.48 (m, 2H), 2.80e2.94 (m,
6.1.31. N-[3-Dimethylamino-1-(2-naphthyl)propyl]-3-
(4-methoxyphenyl)propionamide HCl {C6}
3-(4-Methoxyphenyl)propionic acid (220 mg, 1.22 mmol)
1H), 2.88 (s, 6H), 3.12e3.22 (m, 1H), 5.25 (t, 1H, J ¼ 8.4 Hz),
7.36e7.43 (m, 2H), 7.44e7.51 (m, 2H), 7.53e7.60 (m, 3H),
7.81e7.95 (m, 5H). 13C NMR d 30.0, 42.0, 52.0, 54.5, 65.0,
82.0, 85.0, 120.0, 124.0, 125.0, 126.0, 126.1, 127.0, 127.1,
129.0 (2 C:s), 130.0, 131.5 (2 C:s), 133.0, 133.1, 137.5,
152.4, 154.0. HRTofMS calcd for C24H24N2O (Mþ) m/z
356.1889, found 356.1887.
1
yielded 80 mg {C6} (93%). H NMR d 2.10e2.22 (m, 2H),
2.48e2.61 (m, 2H), 2.61e2.70 (m, 1H), 2.65 (s, 6H), 2.76e
2.89 (m, 3H), 3.66 (s, 3H), 5.07 (dd, 1H, J ¼ 6.2, 8.4 Hz),
6.71 (d, 2H, J ¼ 8.4 Hz), 7.06 (d, 2H, J ¼ 8.4 Hz), 7.34e
7.39 (dd, 1H, J ¼ 1.8, 8.4 Hz), 7.42e7.50 (m, 2H), 7.71 (s,
1H), 7.78e7.86 (m, 3H). 13C NMR d 30.6, 31.2, 37.6, 42.7
(2 C:s), 50.9, 54.3, 55.5, 113.5 (2 C:s), 124.5, 125.0, 125.8,
126.0, 127.3, 127.7, 128.3, 129.2 (2 C:s), 132.5, 133.0,
133.5, 138.5, 158.2, 173.7. HRTofMS calcd for C25H30N2O2
(Mþ) m/z 390.2307, found 390.2316.
6.2. Biological activity
R-SAT-testing: R-SATÔ assays for pharmacological testing
were performed as previously described, with the following
modifications. NIH-3T3 cells were grown to 80% confluence
in Dulbecco’s modified Eagle’s medium (DMEM) supple-
mented with 10% bovine calf serum (Hyclone) and 1% peni-
cillin/streptomycin/glutamine (Invitrogen). Cells were
transfected in roller bottles for 18 h with the human urotensin
II receptor and the b-galactosidase marker. After the 18 h
transfection, cells were trypsinized, harvested, and frozen.
Aliquots of frozen cell batches were thawed and tested for
response to control compound to perform quality control
before initiation of pharmacological testing, ensuring the cor-
rect pharmacological response and sufficient sensitivity. To
initiate the pharmacological assay, cells were thawed rapidly
and prepared in DMEM media containing 0.4% calf serum
(Hyclone), 30% UltraCulture (Biowhittaker), and 1%
6.1.32. N-[3-Dimethylamino-1-(2-naphthyl)propyl]-3-
cinnamamide HCl {C7}
Cinnamic acid (162 mg, 1.17 mmol) yielded 60 mg {C7}
1
(76%). H NMR d 2.37e2.45 (m, 2H), 2.88e2.95 (m, 1H),
2.91 (s, 6H), 3.13e3.29 (m, 1H), 5.30 (t, 1H, J ¼ 7.0 Hz),
6.75 (d, 1H, J ¼ 15.8 Hz), 7.34e7.42 (m, 3H), 7.45e7.52
(m, 2H), 7.53e7.59 (m, 4H), 7.82e7.95 (m, 4H). 13C NMR
d 30.7, 42.1 (2 C:s), 55.4, 65.6, 120.0, 124.4, 125.3, 126.0,
126.2, 127.4, 127.6 (2 C:s), 127.7, 128.6, 128.7 (2 C:s),
129.7, 133.0, 133.4, 134.8, 138.0, 141.4, 167.0. HRTofMS
calcd for C24H26N2O (Mþ) m/z 358.2045, found 358.2045.

F. Lehmann et al. / European Journal of Medicinal Chemistry 42 (2007) 276e285
285
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