Synthesis and 5-HT2A, 5-HT1A and α1- binding affinities of 2-[2-hydroxy-3-(pyridin-3-yl-methyl)amino]-, 2-[2-hydroxy-3-(2-pyridin-2-yl-ethyl)amino]- and 2-[2-hydroxy-3-(4-N-methyl- piperazin-1-yl)-amino]propoxybenzaldehyde

Article abstract of DOI:10.1002/ardp.200600123

Some oxime ether-substituted aryloxypropanolamines 3-5, structurally related to the active metabolite 2 of sarpogrelate 1, were synthesized and tested for their affinities at 5-HT_2A and 5-HT_1A serotoninergic receptors as well as at t

Full text of DOI:10.1002/ardp.200600123

Arch. Pharm. Chem. Life Sci. 2007, 340, 135–139
E. Orlandini et al.
135
Full Paper
Synthesis and 5-HT2A, 5-HT1A and a1-Binding Affinities of 2-[2-
Hydroxy-3-(pyridin-3-yl-methyl)amino]-, 2-[2-Hydroxy-3-(2-
pyridin-2-yl-ethyl)amino]- and 2-[2-Hydroxy-3-(4-N-methyl-
piperazin-1-yl)-amino]propoxybenzaldehyde-O-(substituted)
Benzyl Oximes
Elisabetta Orlandini1, Simona Rapposelli1, Susanna Nencetti1, Gino Giannaccini2, Laura Betti2,
and Aldo Balsamo1
1 Dipartimento di Scienze Farmaceutiche, Universitꢀ di Pisa, Pisa, Italy
2 Dipartimento di Psichiatria Neurobiologia Farmacologia e Biotecnologie, Universitꢀ di Pisa, Pisa, Italy
Some oxime ether-substituted aryloxypropanolamines 3-5, structurally related to the active
metabolite 2 of sarpogrelate 1, were synthesized and tested for their affinities at 5-HT2A and 5-
HT1A serotoninergic receptors as well as at the a1-adrenoceptor. The results show that the com-
pounds possess, at least partially, the ability of the model compounds 1 and 2 to interact with
the 5-HT2A-receptors; they have the same selectivity towards 5-HT2A receptors vs a1-adrenoceptors.
Keywords: Benzyl oximes derivatives / Oximes ether-substituted aryloxypropanolamines / Sarpogrelate analogues /
Serotoninergic and adrenergic activity /
Received: September 20, 2006; accepted: December 19, 2006
DOI 10.1002/ardp.200600123
Introduction
Serotonin (5-HT) is a biogenic amine involved in different
physiological functions, including that of inducing plate-
let activation and aggregation [1]. This effect is mediated
by the activation of 5-HT2A-receptors which are located on
platelets, as well as centrally. Consequently, the antago-
nists of this 5-HT-receptor subtype may be considered to
Figure 1. Structure of compounds 1 and 2.
be good tools in the treatment of thrombosis [2] and car-
diovascular disease [3, 4].
Sarpogrelate 1 (Fig. 1) is a 5-HT2A-receptor antagonist
now clinically available in Japan for the treatment of the
peripheral arterial disease [5–7]. Starting from the obser-
vation that also the hydrolysis product of sarpogrelate
(M-1, 2; Fig. 1) is a potent 5-HT2A-receptor antagonist,
some compounds structurally related to M-1 were devel-
oped [8, 9], in which different substituents were tested on
the aminic nitrogen and the aryloxy group. As a result, it
was shown that these molecular portions play impor-
tant, albeit at times unexpected, roles in determining the
5-HT2A affinity level of the new compounds. Furthermore,
despite the broad variety of substituents tested, to our
knowledge, less attention has been dedicated to the
effects on the affinity of substituents on the aminic nitro-
gen bearing a hetero aromatic portion; analogously,
from literature data no studies appear to have been car-
ried out on analogues of M-1 in which its 3-methoxyphe-
nylethyl group is replaced by a more complex molecular
Correspondence: Prof. Elisabetta Orlandini, Dipartimento di Scienze
Farmaceutiche, Via Bonanno 6, I-56126 Pisa, Italy
E-mail: eorlandini@farm.unipi.it
Fax: +39 050 22 195-77
i 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

136
E. Orlandini et al.
Arch. Pharm. Chem. Life Sci. 2007, 340, 135–139
Figure 2. Structure of compounds 3–5.
portion possessing conformational freedom different
from that of an aliphatic chain.
Scheme 1. Synthesis of amino alcohols 3a–c, 4a, b and 5a, c.
On the basis of these considerations and with the aim
of getting further information about the structural
requirements for 5-HT2A affinity, we designed and synthe-
sized some compounds of types 3 and 4 which can be
viewed as analogues of M-1 2, in which the substituent on
amino nitrogen presents a hetero aromatic portion such
as that 3-methylpyridinylic or 2-ethylpyridinylic, respec-
tively. In addition, in order to explore the effects on the 5-
HT2A affinity of a new type of N-substitution, also 5a and
5c were synthesized, in which the alkylpyridine of 3a, c
and 4a,b are replaced by a 1-amino-4-methyl piperazine
moiety.
into their potassium salts, and were then allowed to react
with epibromohydrine to yield the corresponding epox-
ides 9a–c. Treatment of the appropriate epoxide 9 with 3-
aminomethylpyridine, 2-aminoethylpyridine or 1-
amino-4-methylpiperazine afforded the compounds 3a–
c, 4a, b and 5a, c, respectively.
Results and conclusions
The affinity of the new compounds 3a–c, 4a, b and 5a, c
for 5-HT2A, 5HT1A and a1 receptors was determined by radi-
oligand-binding assays carried out on rat cerebral cortex,
using [3H] ketanserin, [3H] 8-OH-DPAT, [3H] prazosin as the
specific radioligands, respectively.
Results, expressed as Ki (nM), are reported in Table 1,
together with those obtained in the same tests with sar-
pogrelate 1 and M-1 2, taken as reference drugs.
All the new compounds showed a determinable affi-
nity for 5-HT2A receptors, with the Ki values ranging from
9700 nM of 3b to 97.7 nM of 4a. In the same tests, the sar-
pogrelate 1 and M-1 2 exhibited Ki values of 22 and
9.7 nM, respectively. In particular, among the 3-methyl-
pyridinyl compounds 3a–c, the o-chloro-substituted 3b
and the phenyl unsubstituted 3a exhibited an affinity,
with Ki values of 9700 nM and 1990 nM, respectively; the
3,4-methylendioxy compound 3c showed an intermedi-
ate affinity (Ki = 5620 nM). An affinity comparable to that
of 3a and 3c was shown by their corresponding piperazi-
nyl analogues 5a and 5c (Ki values of 2000 and 6450 nM,
respectively).
Moreover, in these new compounds 3–5 (Fig. 2) the
ethylene linker between the two aromatic portion of 1
and 2 is substituted by a hetero atomic spacer C–O–
N=C– with the E configuration around the oxime double
bond. This molecular portion has been successfully used
in the design of drugs of other classes [10–13] and
allowed us to obtain new compounds endowed with a
good biological activity. This new linker which differs
from the starting one in the steric and electronic charac-
teristics might interact with the receptor through a
hydrogen bond or might direct the aryl group in a differ-
ent manner with respect to the linker present in the
model compounds 1 and 2.
All new compounds were tested for their binding affi-
nity to 5-HT2A, 5HT1A and a1 receptors, to verify how the
structural modifications can modulate the affinity
towards these receptors.
Chemistry
Among the new compounds, 4a and 4b showed the
highest affinity, with Ki values of 97.7 and 182 nM,
respectively. Moreover, the more active compound 4a
showed binding value appreciably higher than those of
M-1 2 (9.7 nM) and sarpogrelate 1 (22 nM).
Aminoalcohols 3a–c, 4a, b and 5a, c were synthesized as
shown in Scheme 1. Reaction of salicylaldehyde 6 with
the appropriate O-arylmethyloxyamines hydrochlorides
7a–c in a CHCl3 :H2O (1:1) mixture yielded the corre-
sponding oxime ethers 8a–c, which were transformed
i 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.archpharm.com

Arch. Pharm. Chem. Life Sci. 2007, 340, 135–139
Synthesis and binding affinity of Oxime ethers
137
Table 1. Affinity of compounds 3a–c, 4a, b and 5a, c for 5-HT2A, 5-HT1A and a1 receptors.
Compound
Ki (nM)a)
5-HT1A
Ki Ratio
a1/5-HT2A
5-HT2A
a1
5-HT1A/5-HT2A
3a
3b
3c
4a
4b
5a
5c
1990 l 80
9700 l 430
5620 l 250
97.7 l 4.2
182 l 8.0
2000 l 85
6450 l 290
22 l 1.0
A10000b)
A10 000b)
A10 000b)
A10 000b)
A10 000b)
A10 000b)
A10 000b)
A10 000b)
2000 l 90
500 l 20
A5.0
A1.0
1.5
64.4
41.6
A5.0
1.4
A5.0
A1.0
A10000b)
8910 l 400
6300 €280
7580 l 340
A10000b)
9500 l 420
A10000b)
3160 l 140
A1.1
A102.3
A54.9
A5.0
A1.5
90.9
Sarpogrelate 1
M-1 2
A454.5
325.7
9.7 l 0.4
51.5
a)
Ki values are taken from three experiments, expressed as means l SEM.
The Ki values were not calculated because the inhibition percentages at 10 lM were too low.
b)
tra of all compounds were obtained with a Gemini 200 spectro-
meter (Varian Inc., Palo Alto, CA, USA) operating at 200 MHz, in
a approx. 2% solution of CDCl3. Analytical TLCs were carried out
on 0.25 mm layer silica gel plates containing a fluorescent indi-
cator; spots were detected under UV light (254 nm). Column
chromatography was performed using 70–230 mesh silica gel.
Mass spectra were detected with a Hewlett Packard 5988A spec-
trometer (Hewlett-Packard, Palo Alto, CA, USA). Evaporation was
performed in vacuo (rotating evaporator); the O-arylmethyloxya-
mines to be used for the preparation of the desired compounds
3–5, not commercially available, were prepared following the
synthetic method described in the literature [14]. Na2SO4 was
always used as the drying agent. Elemental analyses(C, H, N)
were performed in our analytical laboratory and agreed with
theoretical values to within l 0.4% (cf. Supplemental Material).
At the 5HT1A subtype receptor the new compounds 3a-
c, 4a, b and 5a, c showed high Ki values (ranging from
7580–10000). The Ki ratio between 5-HT1A and 5-HT2A was
not significantly different to the one for compounds 3
and 5, but is higher for compounds 4a and 4b.
The new compounds are devoid of any affinity towards
the a1-adrenergic receptor. The reference drug sarpogre-
late 1 and its metabolite 2 show, at this receptor, Ki values
of 2000 and 500 nM, respectively. The Ki ratio between a1/
5HT2A for the most active compounds 4a and 4b show
values comparable to those of the reference drugs, (102.0,
54.9 for 4a and 4b and 90.9, 51.5 for 1 and 2, respectively).
The results indicate that with the newly synthesized
compounds 3–5, only the 2-ethylpyridinyl moiety of 4 is
the one that better addresses the affinity towards the ser-
otoninergic receptors. This indicates that the presence of
this substituent, on the amino moiety of the aminopro-
panol chain, does not prevent the interaction of this
group with the receptor.
The introduction of the more rigid amino-etheral
sequence as in the 4a and 4b derivatives, with respect to
the more flexible ethylenic linker of 1 and 2, is able to
maintain an appreciable affinity on 5-HT2A-receptor for
these molecules.
In conclusion, given that this work has not obtained
compounds possessing a greater affinity for the 5-HT2A
receptor than that of the model compound M-1 2, how-
ever, it allowed us to identify in the compound 4a a new
lead, that could be a good start point to design new
ligands endowed with high affinity and selectivity
towards 5-HT2A receptor.
Chemistry
General procedure for the synthesis of 2-Hydroxy-
benzaldehyde-O-benzyl oxime 8a, 2-Hydroxy-
benzaldehyde-O-(o-chlorobenzyl) oxime 8b and
2-Hydroxy-benzaldehyde-O-(3,4-methylenedioxy-benzyl)
oxime 8c
A mixture of the appropriate O-aryloxyamine 7a–c (0.02 mol) in
H2O (10 mL) and the salicylaldehyde 6 (2.44 g, 0.02 mol) in CHCl3
(30 mL) was stirred at room temperature for 24 h. The organic
phase was separated, and the aqueous solution was extracted
twice with CHCl3. Evaporation of the dried and filtered organic
extracts afforded a residue consisting almost exclusively of the
corresponding phenols 8a–c.
8a: (81%) 1H-NMR: d 5.20 (s, 2H); 6.91–7.43 (m, 9H); 8.23 (s, 1H);
9.76 (brs, 1H). 8b: (50%); 1H-NMR: d 5.26 (s, 2H); 6.91–7.45 (m,
8H); 8.19 (s, 1H); 9.60 (brs, 1H). 8c: (67%); 1H-NMR: d 5.08 (s, 2H);
5.98 (s, 2H); 6.80–7.00 (m, 5H); 7.12–7.29 (m, 2H); 8.20 (s, 1H);
9.80 (brs, 1H).
General procedure for the synthesis of 2-
(Glycidoxy)benzaldehyde O-substituted benzyl oxime
9a–c
A solution of the appropriate 2-hydroxy-benzaldehyde-O-substi-
tuted benzyl oxime 8a–c (3.52 mmol) in t-BuOH (5 mL) was
added to a solution of KOH (0.40 g, 7.18 mmol) in t-BuOH (5 mL).
Experimental
General
Melting points were determined on a Kofler hot-stage apparatus
(C. Reichert, Vienna, Austria) and are uncorrected. 1H-NMR spec-
i 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.archpharm.com

138
E. Orlandini et al.
Arch. Pharm. Chem. Life Sci. 2007, 340, 135–139
The resulting mixture was added dropwise to a stirred and
cooled (08C) solution of epibromohydrine (0.62 mL, 7.18 mmol)
in t-BuOH (1 mL). After stirring at room temperature for 48 h,
the mixture was evaporated, taken up with Et2O and washed
with H2O. The organic phase was then dried and evaporated to
give the desired products 9a–c. 9a: (40%); 1H-NMR: d 2.74–2.94
(m, 2H), 3.25–3.40 (m, 1H); 3.96–4.04 (m, 1H); 4.15–4.27 (m, 1H);
5.23 (s, 2H); 6.86–7.02 (m, 4H); 7.27–7.84 (m, 5H); 8.58 (s, 1H).MS
(m/z): M+ 283 (1.1).9b: (55%); 1H-NMR: d 2.74–2.94 (m, 2H), 3.37–
3.43 (m, 1H); 3.98–4.04 (m, 1H); 4.18–4.22 (m, 1H); 5,35 (s, 2H);
6.86-7.83 (m, 8H, Ar); 8.63 (s, 1H). 9c: (55%); 1H-NMR: d 2.73–2.76
(m, 1H), 2.90 (t, 1H, J = 5 Hz); 3.30–3.43 (m, 1H); 3.94–4.02 (m,
1H); 4.18–4.26 (m, 1H); 5.11 ( s, 2H); 5.96 (s, 2H); 6.90–7.00 (m,
5H); 7.22–7.40 (m, 2H); 8.56 (s, 1H).
Biological assays
5-HT2A-Receptor binding
Cerebral cortex was dissected from rat brain and the tissue was
homogenized in 10 volumes of ice-cold 50 mM Tris-HCl buffer at
pH 7.4. The homogenate was centrifuged at 48000 g for 15 min
at 48C. The resulting pellet was suspended in 35 volumes of
50 mM Tris-HCl buffer, incubated at 378C for 10 min to remove
endogenous 5-HT, and centrifuged at 48000 g for 15 min at 48C.
The resulting pellet was frozen at –808C until the time of assay.
The binding assay was performed according to the method
reported in the literature [15] incubating aliquots of the mem-
brane fraction (0.2–0.3 mg of protein) in Tris-HCl buffer at
pH 7.4 with approximately 0.48 nM [3H] ketanserin (Perkin-
Elmer Life Science, Milano, Italy: 77.2 Ci/mmol) in a final volume
of 1 mL. Incubation was carried out at 378C for 15 min. Non-spe-
cific binding was defined in the presence of 10 lM spiperone.
The binding reaction was concluded by filtration through What-
man GF/C glass fiber filters under reduced pressure. Filtrates
were washed four times with 5 mL aliquots of ice-cold buffer and
placed in scintillation vials. The receptor-bound radioactivity
was measured as described above.
Synthesis of 2-[2-Hydroxy-3-(pyridin-3-yl-methyl)amino]
propoxy benzaldehyde-O-benzyl- (3a), –O-(o-
chlorobenzyl)- (3b) and –O-3,4-methylendioxy-benzyl-
(3c) oximes, 2-[2-Hydroxy-3-(2-pyridin-2-yl-
ethyl)amino]propoxy benzaldehyde O-benzyl- (4a), –O-
(o-chlorobenzyl)- (4b) -oximes and 2-[2-Hydroxy-3-(4-
methyl-piperazin-1-yl)amino] propoxy benzaldehyde O-
benzyl- (5a) and –O-3,4-methylendioxy-benzyl- (5c)
5-HT1A-Receptor binding
Cerebral cortex was dissected from rat brain and the tissue was
homogenized in 10 volumes of ice-cold 50 mM Tris-HCl buffer at
pH 7.4. The homogenate was centrifuged at 48000 g for 15 min
at 48C. The resulting pellet was suspended in 35 volumes of
50 mM Tris-HCl buffer, incubated at 378C for 10 min to remove
endogenous 5-HT, and centrifuged at 48 000 g for 15 min at 48C.
The resulting pellet was frozen at –808C until the time of assay.
The binding assay was performed according to the method
reported in the literature [16] incubating aliquots of the mem-
brane fraction (0.2–0.3 mg of protein) in Tris-HCl buffer at
pH 7.4 with approximately 0.5 nM [3H] 8-OH-DPAT (Perkin-Elmer
Life Science: 106 Ci/mmol) in a final volume of 1 mL. Incubation
was carried out at 378C for 15 min. Non-specific binding was
defined in the presence of 10 lM 8-OH-DPAT. The binding reac-
tion was concluded by filtration through Whatman GF/C glass
fiber filters under reduced pressure. Filtrates were washed four
times with 5 mL aliquots of ice-cold buffer and placed in scintil-
lation vials. Specific binding was obtained by subtracting non-
specific binding from total binding and approximated to 85-90%
of total binding.
oximes
LiClO4 (3.76 g, 35.35 mmol) and the appropriate substituted
amine (3.9 mmol) were added to a stirred solution of the appro-
priate glycidoxy derivatives 9a–c (3.5 mmol) in anhydrous
CH3CN (15 mL). After stirring at room temperature for 24 h, the
solution was diluted with Et2O and washed with a solution of
NaCl. The organic phase was then dried, filtered and evaporated,
to give an oily residue, which was purified by transformation of
the corresponding oxalate salt, and crystallised from the proper
solvent, to give the desired amines 3a–c, 4a, b, 5a, c as oxalate
salts. 3a: MeOH/Et2O; 1H-NMR: (DMSO) d 2.98–3.18 (m, 2H); 4.00
(brs, 2H); 4.23 (s, 2H); 5.17 (s, 2H); 6.95–7.08 (m, 2H); 7.35–7.42
(m, 6H); 7.66–7.69 (m, 1H); 7.92–7.96 (m, 1H); 7.78 (dt, 1H, J =
7.7, 1.8 Hz); 8.50 (brs, 1H); 8.56 (d, 1H, J = 4.5Hz); 8.68 (s, 1H).
1
Anal. Calc.: C23H25N3O36H2C2O4 (C, H, N). 3b: (MeOH): H-NMR
free base: (CDCl3) d 2.80 –2.92 (m, 2H); 3.86 (s, 2H); 4.03–4.13 (m,
5H); 5.33 (s, 2H); 6.88–7.01 (m, 2H); 7.27–7.53 (m, 6H); 7.68–7.72
(m, 2H); 8.44–8.58 (m, 3H). Anal Calc.: C23H24N3O3Cl62H2C2O4 (C,
H, N). 3c: (MeOH): 1H-NMR free base: (CDCl3) d 2.25 –2.90 (brs,
2H); 3.86 (s, 2H); 4.05–4.12 (m, 5H); 5.10 (s, 2H);5.96 (s, 2H); 6.78–
7.01 (m, 5H); 7.27–7.33 (m, 3H); 7.68–7.72 (m, 2H); 8.41 (s, 1H);
8.49–8.58 (m, 2H); Anal Calc.: C24H25N3O562H2C2O4 (C, H, N). 4a:
(EtOH): 1H-NMR: (DMSO) d 3.10–3.38 (m, 6H); 4.06 (brs, 2H); 5.16
(s, 2H); 6.98–7.09 (m, 2H); 7.27–7.40 (m, 6H); 7.65–7.77 (m, 2H);
8.48–8.57 (m, 3H); Anal Calc.: C24H27N3O362H2C2O4 (C, H, N). 4b:
a1-Receptor binding
Rat cerebral cortex was homogenized in 20 volumes of ice-cold
50 mM Tris-HCl buffer at pH 7.7 containing 5 mM EDTA (buffer
T1) in an ultraturrax homogenizer. The homogenate was centri-
fuged at 48000 g for 15 min at 48C. The pellet was suspended in
20 volumes of ice-cold buffer T1. It was then homogenized and
centrifuged at 48000 g for 15 min at 48C. The resulting pellet
was frozen at –808C until the time of assay.
The binding assay was performed according to the method
reported in the literature [17] incubating aliquots of the mem-
brane fraction (0.2–0.3 mg of protein) in 50 mM Tris-HCl buffer
at pH 7.7 with approximately 0.2 nM [3H] prazosin (Perkin-Elmer
Life Science: 81 Ci/mmol) in a final volume of 1 mL. Incubation
was carried out at 258C for 60 min. Non-specific binding was
defined in the presence of 1 lM prazosin. The binding reaction
was concluded by filtration through Whatman GF/C glass fiber
filters under reduced pressure. Filtrates were washed four times
1
(MeOH): H-NMR: (DMSO) d 3.04–3.40 (brs, 6H); 4.03 (brs, 2H);
5.25 (s, 2H); 6.93–7.10 (m, 2H); 7.20–7.58 (m, 6H); 7.62–7.80 (m,
2H); 8.42–8.54 (m, 2H); 8.60 (m, 1H) Anal Calc.:
1
C24H26N3O3Cl62H2C2O4 (C, H, N). 5a: (i-PrOH): H-NMR: (DMSO) d
2.26 (s, 3H); 2.67–2.75 (brs, 2H); 3.16–3.27 (brs, 4H); 3.3–4.10
(brs); 5.17 (s, 2H); 5.84 (brs); 6.01 (s, 2H); 6.96–7.11 (m, 3H); 7.36–
7.48 (m, 5H); 7.68-7.72 (m, 1H); 8.59 (s, 1H). Anal Calc.:
C22H30N4O362H2C2O4 (C, H, N). 5c (EtOH): 1H-NMR: (DMSO) d 2.26
(s, 3H); 2.67–2.75 (brs, 2H); 2.90–3.16 (brs, 4H); 3.5–4.12 (brs);
4.50–4.70 (brs, 2H); 5.06 (s, 2H); 6.01 (s, 2H); 6.90–7.10 (m, 5H);
7.36–7.48 (m, 1H); 7.68–7.72 (m, 2H); 8.56 (s, 1H). Anal. Calc.:
C23H30N4O562H2C2O4 (C, H, N).
i 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.archpharm.com

Arch. Pharm. Chem. Life Sci. 2007, 340, 135–139
Synthesis and binding affinity of Oxime ethers
139
with 5 mL aliquots of ice-cold buffer and placed in scintillation
vials. Specific binding was obtained by subtracting nonspecific
binding from total binding and approximated to 85–90% of
total binding.
[6] R. Kikumoto, H. Hara., K. Ninomiya, M. Osakabe, et al., J.
Med. Chem. 1990, 33, 1818–1823.
[7] K. Houkin, N. Nakayama, T. Nonaka, I. Koyanagi, J. Int.
Med. Res. 2006, 34, 65–2.
Compounds were dissolved in buffer and added to the assay
mixture. The inhibition of specific binding was determined in
the presence of a single concentration (10 lM) of the potential
displacing agent. The concentration of tested compounds that
produces 50% inhibition of specific radioligand binding (IC50)
was determined by log-probit analysis with increasing concen-
trations of the displacer, each performed in triplicate. Inhibition
constants (Ki) were calculated according to Cheng and Prusoff
[18] equation Kd of [3H] ketanserin binding to cortex membranes
was 0.48 nM (5-HT2A); Kd of [3H] 8-OH-DPAT binding to cortex
membranes was 2 nM (5-HT1A) and Kd of [3H] prazosin binding to
cortex membranes was 0.24 nM (a1). The protein concentration
was determined according to the method of Lowry [19], using
bovine serum albumin as a standard.
[8] N. Tanaka, R. Goto, R. Iro, M. Hayakawa, et al., Chem.
Pharm. Bull. 2000, 48, 245–253.
[9] N. Tanaka, R. Goto, R. Iro, M. Hayakawa, et al., Chem.
Pharm. Bull. 2000, 48, 1729–1739.
[10] B. Macchia, A, Balsamo, A. Lapucci, A. Martinelli, et al., J.
Med. Chem. 1985, 28, 153–165.
[11] A. Balsamo, G. Broccali, A. Lapucci, B. Macchia, et al., A.
Rossello, J. Med. Chem. 1989, 32, 1398–1401.
[12] B. Macchia, A. Balsamo, A. Lapucci, A. Martinelli, et al., J.
Med. Chem. 1990, 33, 1423–1430.
[13] A. Balsamo, I. Colotta, P. Domiano, A. Guglielmotti, et al.,
Eur. J. Med. Chem. 2002, 37, 391–402.
[14] A. Balsamo, M. S. Belfiore, M. Macchia, C. Martini, et al.,
Eur. J. Med. Chem. 1994, 29, 787–794.
[15] J. E. Leysen, C. J. Niemergeers, J. M. van Neuten, P. M.
References
Laduron, Mol. Pharmacol. 1982, 21, 301–314.
[1] J. G. White, Scand. J. Haematol. 1970, 7, 145–151.
[2] J. M. van Nueten, Fed. Proc. 1983, 42, 223–227.
[16] A. Dalpiaz, P. A. Borea, S. Gessi, S. Gilli, Eur. J. Pharmacol.
1996, 312, 107–114.
[3] E. Horibe, K. Nishigaki, S. Minatoguchi, H. Fujiwara, Circ
J. 2004, 68, 68–72.
[17] L. Betti, M. Botta, F. Corelli, M. Floridi, et al., Eur. J. Med.
Chem. 2002, 45, 3603–3611.
[4] H. Saini, N. Takeda, K. Goyal Ramesh, H. Kumamoto, et
al., Cardiovasc Drug Rev. 2004, 22, 27–54.
[18] Y. C. Cheng, W. H. Prusoff, Biochem. Pharmacol. 1973, 22,
3099–3108.
[5] H. Hara, M. Osakabe, A. Kitajima, Y. Tamao, R. Kikumoto,
[19] O. H. Lowry, N. J. Rosenbrough, A. L. Farr, R. J. Randall, J.
Biol. Chem. 1951, 193, 265–267.
Thromb. Haemost. 1991, 65, 415–420.
i 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.archpharm.com