Quinoline- and isoquinoline-sulfonamide derivatives of LCAP as potent CNS multi-receptor - 5-HT1A/5-HT2A/5-HT7 and D 2/D3/D4 - Agents: The synthesis and pharmacological evaluation

Article abstract of DOI:10.1016/j.bmc.2011.12.039

Two series of arylpiperazinyl-alkyl quinoline-, isoquinoline-, naphthalene-sulfonamides with flexible (13-26) and semi-rigid (33-36) alkylene spacer were synthesized and evaluated for 5-HT_1A, 5-HT_2A, 5-HT₆, 5-HT₇ and selected compounds for D₂, D₃, D₄ receptors. The compounds with a mixed 5-HT and D receptors profile 16 (N-{4-[4-(3-chlorophenyl)-piperazin-1-yl]-butyl}-3- quinolinesulfonamide) and 36 (4-(4-{2-[4-(4-chloro-phenyl)-piperazin-1-yl]- ethyl}-piperidine-1-sulfonyl)-isoquinoline), displaying antagonistic activity at 5-HT₇, 5-HT_2A, D₂ postsynaptic sites, produced antidepressant-like effects in the forced swim test in mice and showed significant anxiolytic activity in the plus-maze test in rats. The lead compound 36, a multi-receptor 5-HT_2A/5-HT₇/D₂/D ₃/D₄ agent, also displayed significant antipsychotic properties in the MK-801-induced hyperlocomotor activity in mice.

Full text of DOI:10.1016/j.bmc.2011.12.039

Bioorganic & Medicinal Chemistry 20 (2012) 1545–1556
Contents lists available at SciVerse ScienceDirect
Bioorganic & Medicinal Chemistry
journal homepage: www.elsevier.com/locate/bmc
Quinoline- and isoquinoline-sulfonamide derivatives of LCAP as potent CNS
multi-receptor—5-HT1A/5-HT2A/5-HT7 and D2/D3/D4—agents: The synthesis
and pharmacological evaluation
Paweł Zajdel a, , Krzysztof Marciniec , Andrzej Maslankiewicz , Grzegorz Satała , Beata Duszynska ,
Andrzej J. Bojarski c, Anna Partyka d, Magdalena Jastrze˛bska-Wie˛sek d, Dagmara Wróbel d,
Anna Wesołowska d, Maciej Pawłowski a
⇑
b
b
c
c
´
´
a Department of Medicinal Chemistry, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
b Department of Organic Chemistry, Medical University of Silesia, 4 Jagiellon´ska Street, 41-200 Sosnowiec, Poland
c Department of Medicinal Chemistry, Institute of Pharmacology, Polish Academy of Sciences, 12 Sme˛tna Street, 31-343 Kraków, Poland
d Department of Clinical Pharmacy, Jagiellonian University Medical College, 9 Medyczna Street, 30-688 Kraków, Poland
a r t i c l e i n f o
a b s t r a c t
Article history:
Two series of arylpiperazinyl–alkyl quinoline-, isoquinoline-, naphthalene-sulfonamides with flexible
Received 20 October 2011
Revised 14 December 2011
Accepted 17 December 2011
Available online 4 January 2012
(13–26) and semi-rigid (33–36) alkylene spacer were synthesized and evaluated for 5-HT1A, 5-HT2A
,
5-HT6, 5-HT7 and selected compounds for D2, D3, D4 receptors. The compounds with a mixed 5-HT and
D receptors profile 16 (N-{4-[4-(3-chlorophenyl)-piperazin-1-yl]-butyl}-3-quinolinesulfonamide) and
36 (4-(4-{2-[4-(4-chloro-phenyl)-piperazin-1-yl]-ethyl}-piperidine-1-sulfonyl)-isoquinoline), displaying
antagonistic activity at 5-HT7, 5-HT2A, D2 postsynaptic sites, produced antidepressant-like effects in
the forced swim test in mice and showed significant anxiolytic activity in the plus-maze test in rats.
The lead compound 36, a multi-receptor 5-HT2A/5-HT7/D2/D3/D4 agent, also displayed significant
antipsychotic properties in the MK-801-induced hyperlocomotor activity in mice.
Keywords:
Quinolinesulfonamides/
isoquinolinesulfonamides
Long-chain arylpiperazines
5-HT2A receptor antagonist
5-HT7 receptor antagonist
D2 antagonist
Ó 2011 Elsevier Ltd. All rights reserved.
Depression
Anxiety
Schizophrenia
1. Introduction
Recently, the 5-HT7 receptor (5-HT7R) has emerged as a new
target with a potential for the treatment of psychiatric disorders.2
The emergence of depressive symptoms indicates pathology in
the central nervous system (CNS), which affects the functioning
of an individual in the society and significantly deteriorates the
quality of life. Despite remarkable advances in the treatment of
depression, a great many patients remain undertreated. Regardless
of the mechanism of drug action, the inefficacy of antidepressant
treatment still results from the delayed onset of action and certain
side-effects, such as, emesis or sexual dysfunction.
Although the pathology of depression has not been fully under-
stood yet, for many years the development of antidepressant drugs
has been associated with alteration in norepinephrine/serotonin/
dopamine systems. Among the multiple serotonin receptors that
have been widely studied as a target for the development of
antidepressant agents, 5-HT1A and 5-HT2A subtypes have a promi-
nent position.1
It has also been found that several antipsychotics and antidepres-
sants display high affinity for 5-HT7Rs.3 Furthermore, the distribu-
tion of 5-HT7Rs in relevant regions of the brain provides
information on their significant involvement in the control of the
CNS.4 Their high density in the hypothalamus (particularly in the
suprachiasmatic nucleus) has been associated with the control of
circadian rhythms. Thalamic and cortical 5-HT7Rs might be impor-
tant to sleep and mood regulation; the presence of 5-HT7Rs in the
hippocampus highlights their potential involvement in learning
and memory, as well as in emotional processes.5 Engagement of
5-HT7Rs in mood regulation seems very important regarding the
co-existence of depression and anxiety disorders. In approximately
30% of patients with depression anxiety symptoms may occur, and
in about 50% of stressed people depression is likely to develop.
In support of the involvement of 5-HT7Rs in depression it is pro-
posed that blockade of 5-HT7Rs produces an anti-immobility effect
in the forced swim test.6,7 As was later reported by Abbas et al. and
Sarkisyan et al., the antidepressant-like effect of the well-known
⇑
Corresponding author. Tel.: +48 12 620 54 50; fax: +48 12 620 54 05.
E-mail address: mfzajdel@cyf-kr.edu.pl (P. Zajdel).
0968-0896/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved.
doi:10.1016/j.bmc.2011.12.039

1546
P. Zajdel et al. / Bioorg. Med. Chem. 20 (2012) 1545–1556
antipsychotic drugs amisulpride and aripiprazole, respectively,
was most likely mediated by their 5-HT7R antagonism.8,9
Amisulpride and aripiprazole further support the hypothesis that
antipsychotic drugs not only alleviate the negative symptoms of
schizophrenia, but also help conquer depression.10
Of the numerous, structurally diverse 5-HT7 receptor ligands,
several antagonists have been examined so far, for example SB-
269970—a sulfonamide derivative,11 sulfon derivatives (reported
by Raubo et al.)12 or DR-4004—a tetrahydrobenzindole analog13
(Fig. 1).
F
N
N
H
H
N
N
O
O
N
N
II
I
Cl
Cl
Ki (5-HT2A) = 17.5 nM
Ki (5-HT7)
7 nM
Ki (5-HT2A) = 19.4 nM
Ki (5-HT7) = 0.79 nM
=
Figure 2. Representatives of the oxindole series of 5-HT7R ligands.
Several 5-HT7R ligands, for example SB-269970 and SB-656104,
are currently used as references for in vitro and in vivo pharmaco-
logical studies, or are templates for the development of novel
5-HT7 agents.14,15 It should be stressed here that in several cases
a search for selective 5-HT7R agents was hampered by the low
selectivity over 5-HT1ARs, which was due to the relatively close
homology between 5-HT7 and 5-HT1A sites.16–18
N
O
O
S
N
N
PZ-376
i (5-HT1A) = 1099 nM Ki (5-HT7) = 13 nM
Recently Volk et al. have described a series of degraded tetrahy-
drobenzindole derivatives which are connected by different-length
alkylene spacers with the halo-substituted arylpiperazine.19 Those
authors have found that, in contrast to 5-HT7Rs, 5-HT1A sites are
highly sensitive for electron-withdrawing substituents in the phe-
nylpiperazine ring. The introduction of a chlorine or a fluorine
atom into the 3- and 4-position of phenylpiperazine is beneficial
to the acquisition of active 5-HT7 ligands. Although these com-
pounds display low affinity for 5-HT1A receptors, they are devoid
of 5-HT2A receptor selectivity (compounds I, II, Fig. 2). Interest-
ingly, these compounds display anxiolytic activity in such animal
models as, the conflict drinking and the light–dark tests.
Our research team has recently reported on the design, synthe-
sis and pharmacological evaluation of quinolinesulfonamides as
new 5-HT7R ligands. Among them, the N-alkylated quinolinesulf-
onamide containing a perhydroisoquinoline moiety in the amine
core has been classified as a 5-HT7 antagonist, and it displayed
antidepressant activity in the forced swim test in mice
(10 mg/kg) (Fig. 3).20
To carry on our research with a group of azinesulfonamide
derivatives of long-chain arylpiperazines (LCAP), we designed a
new series of quinoline- and isoquinoline-sulfonamides of 3- and
4-chlorophenylpiperazines containing a flexible and semi-rigid
alkylene spacer. In the present paper we described their synthesis,
a biological evaluation for 5-HT7R and other related 5-HTRs as well
as dopamine receptors and determined their therapeutic potential
in the animal models of depression, anxiety and schizophrenia.
K
Figure 3. The structure of PZ-376 a 5-HT7R antagonist.
chlorides were prepared from the corresponding haloquinolines or
4-bromoisoquinoline via their S-methyl analogs obtained in the
reaction with an excess of sodium methanethiolate in the boiling
DMF. S-Demethylation led to the respective azinethiolates which
submitted to oxidative chlorination yielded the desired quinoline-
and isoquinoline-sulfonyl chlorides.21 The coupling of primary
amines with azinesulfonyl chlorides or commercially available 1-
and 2-naphthalenesulfonyl chlorides in methylene chloride in the
presence of Hunig’s base gave the respective sulfonamides 13–26.
The synthesis of the semi-rigid derivatives 33–36 started by
preparing the piperidine-derived secondary amines 31–32
(Scheme 2). The N-Boc-protected piperidine- methanol (27) and
ethanol (28) were activated with tosyl chloride. Then the interme-
diates formed reacted with 4-chlorophenylpiperazine to give the
respective tertiary amines 31 and 32. After Boc removal, the com-
pounds reacted with azinesulfonyl chlorides to yield the tertiary
azinesulfonamides 33–36. All the sulfonamides were converted
into water-soluble hydrochloride salts.
3. Pharmacology
3.1. In vitro evaluation
Radioligand binding assays were employed for determining the
affinity and the selectivity profile of the synthesized compounds
for native 5-HT1A, 5-HT2A, and dopamine D2 as well as for cloned
human 5-HT6 and 5-HT7 receptors. This was accomplished by dis-
placement of [3H]-8-OH-DPAT from rat hippocampus for 5-HT1AR,
[3H]-ketanserin from rat cortex for 5-HT2AR, and [3H]-spiperone
from rat striatum for D2 receptors.22,23 Displacement of [3H]-LSD
and [3H]-5-CT from the cloned human receptor stably expressed
in HEK293 cells was used in 5-HT6R and 5-HT7R binding experi-
ments.20,24 In case of D2 receptors rat striatum and [3H]-spiperone
were used, whereas displacement of [3H]-methylspiperone from
the cloned human receptor stably expressed in HEK293 cells was
used in D3R and D4R binding experiments.25,26
2. Chemistry
The synthesis of the investigated compounds is presented in
Schemes 1 and 2. The starting quinoline- and isoquinoline-sulfonyl
O
O
S
N
N
S
O
N
HO
O
K
i(5-HT7) = 8 nM
SB-269970
pKi(5-HT7) = 8.9
3.2. Functional evaluation
N
HN
The functional activity of the two selected compounds 16 and
36 on intracellular cAMP levels, studied in CHO cells which stably
expressed the human 5-HT7 receptor, was determined at CEREP (Le
Bois l’Eveque, 86600 Celle L’Evescault, France) according to the
previously published methods.27 The functional activity of the
O
DR-4404
pKi(5-HT7) = 8.67
Figure 1. The structure of model 5-HT7R ligands.

P. Zajdel et al. / Bioorg. Med. Chem. 20 (2012) 1545–1556
1547
O
z
O
O
z
O
i
S
S
Cl
N
H
N
X
X
n
X
H2N
N
X
N
n
N
R1
R1
9 - 12
1 - 8
13 - 26
X = N, CH
z = 3-Q, 6-Cl-3-Q, 6-Q,
8-Q, 4-isoQ
n = 1, 2, 3
R1 = 3-Cl, 4-Cl
Scheme 1. The synthesis of the new, flexible quinoline- and isoquinoline-sulfonamides 13–24, and naphthalenesulfonamides 25, 26. Reagents and conditions: (i) DIEA,
CH2Cl2, 0 °C?rt.
Cl
Boc
Boc
Boc
i
ii
N
N
N
N
OH
O
N
S
n
n O
O
n
27, 28
29, 30
31, 32
iii, iv
Cl
O
O
S
z
N
N
X
X
N
n
33 - 36
X = N, CH
z = 3-Q, 7-Q, 4-isoQ
n = 1, 2
Scheme 2. The synthesis of the azinesulfonamides 33–36. Reagents and conditions: (i) TsCl, Py, 0 °C?rt; (ii) 4-chlorophenylpiperazine, Et3N, THF/toluene, 20 h; (iii) TFA/
CH2Cl2 (9/1, v/v); (iv) quinoline- or isoquinoline-sulfonyl chloride, Et3N, CH2Cl2, 0 °C.
selected compounds, based on their receptor affinity for 5-HT1A, 5-
HT2A and D2 receptors, was tested in the commonly used in vivo
models of their antagonistic activity. To determine the postsynap-
tic 5-HT1A receptor antagonistic effects of derivative 16, its ability
to inhibit the 8-OH-DPAT-induced lower lip retraction (LLR) in rats
was tested.28 Compounds 16, 17, 20, 35 and 36 with moderate, but
significant affinity for 5-HT2A and D2 receptors were selected to as-
sess their ability to antagonize the ( )-DOI-induced head twitch re-
sponse in mice29 and the apomorphine-induced climbing behavior
in mice, respectively (Table 2).
long-chain arylpiperazines, the 5-HT (with a significant 5-HT7
component) and dopamine receptor ligands, as potential psycho-
tropic agents for the treatment of anxiety, depression, and/or
schizophrenia.
4.1. Structure–activity relationship studies
The newly synthesized quinoline- and isoquinoline-sulfona-
mides, connected by a polymethylene spacer (C3–C5) to 3- and 4-
chloro-phenylpiperazines (13–24), displayed diversified affinity
for the 5-HT receptors tested (Table 1). At first we examined the im-
pact of linker length between the sulfonamide bond and the amine
moiety on 5-HT7R affinity. A tetramethylene spacer proved to be
optimal for sulfonamides containing 3- and 4-chloro-substituted
phenylpiperazines (PhP) (13 vs 16 and 14 vs 20 and 24).
Then we compared the data obtained for 3-chloro derivatives
with those previously reported for their 2-methoxy analogs (III–
V).20 This modification increased the affinity for 5-HT7Rs (up to
2-folds) and decreased the affinity for 5-HT1ARs. Next, we investi-
gated an influence of the shift of the chlorine atom from 3- to 4-po-
sition. In opposite to Volk et al.,19 who found that in a group of
tetrahydrobenzindole derivatives the chlorine atom in 4-position
decreased the affinity for 5-HT1ARs but maintained the affinity
for 5-HT7Rs at a high nanomolar range, in our experiments such
modification decreased the affinity for both 5-HT1A and 5-HT7Rs.
It is noteworthy that among 3-Cl-PhP derivatives (16–19), the
nitrogen position in the quinolinyl fragment impacted on the affin-
ity for 5-HT7R; we observed the same rank order (8-quinolinyl > 3-
quinolinyl > 6-quinolinyl) as in the case of the previously reported
2-methoxyPhP derivatives.20 In opposite, within a series of 4-
chloro-PhPs (20–22), quinolinyl fragment marginally influenced
affinity for 5-HT7R. However, change of quinolinyl fragment for
4-isoquinolinyl one yielded compound 23 that displayed 4–5 folds
higher affinity for 5-HT7R (Ki = 68 nM).
3.3. Behavioral evaluation
In the successive phase of our investigation, the most
in vitro-active derivatives, that is 16, 17, 20, 35 and 36 were
tested in vivo in the behavioral tests commonly used to predict
antidepressant-, anxiolytic- and/or antipsychotic-like activity.
The potential antidepressant activity was evaluated in the forced
swim test (FST) in mice.30 To determine the anxiolytic-like activ-
ity of the tested compounds, the elevated plus-maze test in rats
was used. The influence of the effective doses recorded in the
forced swim and the elevated plus-maze tests was studied in
spontaneous locomotor activity in mice and rats, respectively,
in order to exclude the possibility of competing behaviors such
as general locomotor activity. Moreover, spontaneous locomotor
activity and the hyperactivity induced by MK-801 were used to
evaluate the specific antipsychotic-like activity in mice. Imipra-
mine, diazepam, haloperidol and clozapine were used as refer-
ence drugs.
4. Results and discussion
The obtained series of compounds helped to extend the study
aimed at developing new azinesulfonamide derivatives of the

1548
P. Zajdel et al. / Bioorg. Med. Chem. 20 (2012) 1545–1556
Table 1
Binding of the quinoline- and isoquinoline-sulfonamides (III–V, 13–24) and naphthalenesulfonamides (25, 26) for 5-HT receptors
O
z
O
S
N
H
N
X
n
X
N
R1
13 - 26
X = N, CH
Compd
Azinyl/naphthyl
n
R1
Ki SEM (nM)
5-HT6
5-HT1A
3.7 0.6
5-HT2A
5-HT7
79
IIIa
IVa
Va
3-Quinolinyl
6-Quinolinyl
8-Quinolinyl
3-Quinolinyl
3-Quinolinyl
4-Isoquinolinyl
3-Quinolinyl
6-Cl-3-quinolinyl
6-Quinolinyl
8-Quinolinyl
3-Quinolinyl
6-Quinolinyl
7-Quinolinyl
4-Isoquinolinyl
3-Quinolinyl
1-Naphthyl
2
2
2
1
1
1
2
2
2
2
2
2
2
2
3
2
2
2-OCH3
2-OCH3
2-OCH3
3-Cl
4-Cl
4-Cl
3-Cl
3-Cl
3-Cl
3-Cl
4-Cl
4-Cl
4-Cl
4-Cl
4-Cl
3-Cl
3-Cl
NTb
NT
NT
206 17
NT
NT
NT
NT
NT
8
40
53
5
7
132 18
55
126
4
7
13
14
15
16
17
18
19
20
21
22
23
24
25
26
NT
NT
888 37
52
208 18
5043 620
6548 1053
2757 328
139 11
604 57
113 16
6
22
56
42
4
7
3
56
88
69
25
2
6
4
1
155
8
68
74
9
6
397 23
3765 222
339 23
1535 213
1725 109
750 43
2209 150
127
147 13
152 18
771 92
2030 310
868 66
1003 124
5801 750
397 53
56
44
63
3
6
9
310 17
335 28
381 31
211 25
114
268 34
22
68
2
8
334 20
8
36
50
3
7
2-Naphthyl
497 29
1
a
Data taken from Ref. 20.
NT—not tested.
b
Following other authors, who described the effects of replace-
displayed up to twice as high affinity for 5-HT7Rs compared to
their flexible analogs 20 and 22. At the same time, that modifica-
tion decreased the affinity for 5-HT2ARs (10–107 times). To further
examine the semi-rigid spacer aiming at increasing the selectivity
for 5-HT7 sites, we decided to increase the distance between the
piperidine moiety and the piperazine fragment equivalent to the
pentamethylene spacer. The latter modification proved to be favor-
able for the binding of compounds 35 and 36 to 5-HT7 receptors
and selectivity over 5-HT1A sites (Table 5). It thus seems that incor-
poration of the sulfonamide moiety into the piperidine fragment
and the increase of the distance between sulfonamide and the ba-
sic nitrogen atom were beneficial to 5-HT7/5-HT1A selectivity. At
the same time, elongation of the flexible fragment increased affin-
ity for 5-HT2ARs and compounds 35 and 36 lost selectivity over
these sites. Furthermore, on contrary to the favorable replacement
of the 3-quinolinyl fragment with the 4-isoquinolinyl one for 5-
HT7R in the case of flexible sulfonamides (20 vs 23), this modifica-
tion did not significantly change the receptor profile of semi-rigid
compounds (35 vs 36).
It is well known that 5-HTRs may indirectly modulate dopa-
mine release. The recent data also presents that arenecarboxa-
mides of the LCAP derivatives were systematically evaluated as
potent D3 receptor ligands,33 of which the 4-quinolinecarboxamide
derivative SB-277011 was classified as a potent D3 antagonist. It
was further found that quinolinecarboxamides were classified as
mixed D3, 5-HT1A and 5-HT2A ligands and displayed antipsychotic
properties.34 Having based on the above data, in a next move we
wished to verify selectivity of the library representatives over
dopamine D2, D3 and D4 receptors (Table 3). Of the selected flexible
quinolinesulfonamides, compound 16 (a 3-Cl-PhP derivative) dis-
played high affinity for D2 and D3 receptors, while its 4-Cl-PhP ana-
log 20 showed low affinity for the dopamine receptors studied.
Surprisingly, the partly rigidified 4-Cl-PhP derivatives 35 and 36
displayed high affinity for D2, D3 and D4 receptors. Of the tested
compounds, the 4-isoquinolinyl analog displayed the highest
affinity for D3 and D4 sites.
ment of the naphthyl ring with nitrogen-containing aromatic het-
erocycles in different groups of carboxamide derivatives of LCAPs
on the compounds solubility31 or receptor affinity,32 we tried to
determine the impact of that modification on the 5-HT7R and other
related receptors binding profile. For this purpose we synthesized
1-naphthyl and 2-naphthyl sulfonamides, connected by a tetra-
methylene spacer to 3-Cl-PhP, as reference compounds. Compound
25, a 1-naphthyl derivative, was classified as a 5-HT7 receptor li-
gand (Ki = 36 nM) with moderate, 10-fold selectivity over 5-
HT1ARs. On the other hand, the 2-naphthyl derivative (26) was
classified as a dual 5-HT2A/5-HT7 receptor ligand. Neither the
replacement of a 1-naphthyl ring with an 8-quinolinyl one (the
a
-position analog 19) nor 2-naphthyl ring with 3-quinolinyl and
6-quinolinyl counterparts (the b-position analogs 16 and 18,
respectively) has greatly influenced affinity for 5-HT7Rs. At the
same time this modification increased the affinity of quinolinesulf-
onamides 14–17 for 5-HT1ARs. Thus, it has further confirmed that
the nitrogen atom in the distal aromatic ring is unfavorable for
the interaction with 5-HT1ARs; the rank order is as follows:
3-quinolinyl > 6-quinolinyl > 8-quinolinyl.
Interestingly, the affinity of 3-Cl-PhP and 4-Cl-PhP derivatives
for 5-HT2ARs depended upon a kind of substitution of azinyl
and naphthyl fragments. The b-position-substituted quinolinesulf-
onamides 16–18 and 20–22, and 2-naphthenesulfonamide 26
displayed higher affinity for 5-HT2A sites than their
a-position–
substituted counterparts 19, 23, and 26.
Following Vermulen et al.,14 we previously observed in a series
of quinolinesulfonamides that N-alkylation of the sulfonamide
group increased 5-HT7/5-HT1AR selectivity.20 Hence in our present
study we decided to replace the flexible tetramethylene spacer be-
tween the sulfonamide and the basic nitrogen atom with semi-ri-
gid 4-alkylene–piperidine analogs. Such modification was carried
out only for a series of 4-Cl-PhP derivatives which displayed the
lowest affinity for 5-HT1ARs (Table 2). Compounds 33 and 34, con-
taining a sulfonamide bond embedded in 4-methylenepiperidine,

P. Zajdel et al. / Bioorg. Med. Chem. 20 (2012) 1545–1556
1549
Table 2
Binding of rigidified quinoline- and isoquinoline-sulfonamides 33–36 for 5-HT receptors
Cl
O
z
O
S
N
N
X
N
X
X = N, CH
n
Compd
Azinyl
n
Ki SEM (nM)
Ratio S1A/7
5-HT1A
5-HT2A
5-HT6
5-HT7
145
207 11
40
47
33
34
35
36
3-Quinolinyl
7-Quinolinyl
3-Quinolinyl
4-Isoquinolinyl
1
1
2
2
462 62
338 46
8300 920
3210 518
6004 520
761 93
31
59
10570 860
17150 1200
24840 3200
16650 2115
9
3
1.6
207
68
5
9
2
3
Table 4
Table 3
Effects of the tested compounds on the ( )-DOI-induced head twitches response (A)
and on the apomorphine-induced climbing behavior (B) in Swiss albino mice
Binding data of the selected quinoline- and isoquinoline-sulfonamides for dopamine
receptors
a
a
Compd
A ID50 (mg/kg ip)
B ID50 (mg/kg ip)
O
z
O
R1
16
17
20
35
10.09 (9.34–10.84)
4.75 (3.59–5.90)
19.55 (17.06–22.03)
5.12 (4.19–6.04)
20.26 (17.82–22.70)
0.12 (0.07–0.20)
29.40 (wide range)
NTc
60.10 (57.84–62.36)
24.99 (23.60–26.37)
25.49 (23.58–27.40)
—
S
N
N
X
N
X
X= N, CH
n
36
Ketanserinb
Compd Azinyl
Spacer
n
R1
Ki (nM)
a
a
b
b
ID50—the dose inhibiting the head twitches or climbing behavior in mice by
D2
40
4-Cl 163 12 46/82 37/78
D3
D4
50%; confidence limits (95%) given in parentheses; apomorphine (3 mg/kg) evokes
climbing behavior of ca. 100 s duration.
16
20
35
36
3-Quinolinyl
3-Quinolinyl
3-Quinolinyl
Flexible
Flexible
Rigidified
1
1
2
2
3-Cl
6
70/94 30/63
b
Data taken from Ref. 35.
NT—not tested.
4-Cl
4-Cl
56
60
7
9
52/90 63/90
67/93 70/98
c
4-Isoquinolinyl Rigidified
a
Full-binding experiment.
Screening procedure—displacement % at 10À7/10À6
b
.
from 127 to 17150 nM. However, the high affinity of some azine-
sulfonamides tested, for 5-HT7Rs with a mixed 5-HT1A/5-HT2A/5-
HT7 (16, 20) or 5-HT2A/5-HT7 (17, 35, 36) receptor profile and
antagonistic activity at the postsynaptic sites, prompted us to eval-
uate their activity in the FST in mice.
4.2. Functional evaluation
The obtained results indicated that 16 (5–20 mg/kg), 17
(5–20 mg/kg) and 35 (10–30 mg/kg) significantly reduced the
immobility time of mice by 37%, 44% and 54%, when administered
in doses which had no effect of their own on spontaneous locomo-
tor activity (Fig. 4). Compounds 20 (10–30 mg/kg) and 35 (10–
30 mg/kg) were practically inactive in that test; however, in the
case of 20, a tendency to decrease immobility could be observed;
although the obtained results were not statistically significant.
The antidepressant-like activity of 16, 17, and 36 was comparable
to that of imipramine, a conventional antidepressant used as a po-
sitive control, which decreased the immobility time of mice by
26.5% and 52% after administration in doses of 10 and 20 mg/kg,
respectively.
Another important finding of this study is that both selected
compounds 16 and 36 exhibited characteristic properties of anxio-
lytic drugs in the plus-maze test in rats. Compound 16 adminis-
tered in a highest dose (20 mg/kg) significantly increased the
time spent in the open arms. Other parameters measured in that
model were also increased; however, the obtained results did not
reach statistical significance. Moreover, an anxiolytic-like effect
of 16 was not specific since its effective dose (20 mg/kg) modified
the general activity of rats increasing the number of total entries
into open and closed arms and X ambulation (data not shown)
(Table 5). Compound 36 produced anxiolytic-like activity after
administration in all doses tested, that is 2.5, 5 and 10 mg/kg. This
derivative administered in a dose of 10 mg/kg induced a specific
anxiolytic-like effect, having significantly increased the time spent
in the open arms, the percentage of the time spent therein and the
number of entries into the open arms not affecting the parameters
The promising compounds 16 and 36 were selected for func-
tional evaluation for 5-HT7R. The obtained results with CHO cells,
which stably expressed the human 5-HT7 receptor, indicated that
the compounds behaved like antagonists at the h5-HT7R, with
KB = 110 nM for 16 and KB = 90 nM for 36. In addition it was further
found, that compound 16 (10–20 mg/kg) dose-dependently and
significantly attenuated the 8-OH-DPAT–induced LLR in rats (data
not shown). Compounds 16 (2.5–20 mg/kg), 17 (2.5–30 mg/kg), 20
(10–30 mg/kg), 35 (2.5–10 mg/kg) and 36 (10–30 mg/kg) dose-
dependently inhibited the ( )DOI-induced head twitches in mice
(Table 4A). The compounds 16 (10–30 mg/kg), 35 (20–30 mg/kg)
and 36 (20–30 mg/kg) decreased the apomorphine-induced climb-
ing behavior in a dose-dependent and statistically significant man-
ner (Table 4B). Concluding, the results of our in vitro and in vivo
functional study showed that the investigated compounds dis-
played antagonistic activity at postsynaptic 5-HT1A
, 5-HT2A,
5-HT7, and D2 receptors.
4.3. Behavioral evaluation
A number of preclinical studies suggest some role of 5-HT
receptors, in particular 5-HT1A, 5-HT2A, 5-HT6 and 5-HT7 ones, in
many psychiatric disorders. Clinical and preclinical studies have
shown that antidepressant-like effects are mainly produced by
postsynaptic 5-HT1A and/or 5-HT2A receptor antagonists. The re-
cent development of selective 5-HT6 and 5-HT7 receptor antago-
nists gives further substantial support for the interrelationship
between serotonin and depression and/or anxiety.4,36 The affinity
of the new compounds for 5-HT6R was not significant and ranged

1550
P. Zajdel et al. / Bioorg. Med. Chem. 20 (2012) 1545–1556
Table 6
Effects of compounds 16, 36, haloperidol and clozapine on the hiperlocomotor activity
induced by MK-801 in CD-1 mice
Compd dose (mg/kg)
Number of crossings during
60 min mean S.E.M.
Vehicle + vehicle
3514.5 296.5
7577.6 968.2b
6606.6 759.2a
6416.9 422.8a
6551.3 617.7a
F(4,43) = 5.578
P <0.01
Vehicle + MK-801 (0.2)
16 (2.5) + MK-801 (0.2)
16 (5) + MK-801 (0.2)
16 (10) + MK-801 (0.2)
Vehicle + vehicle
Vehicle + MK-801 (0.2)
16 (20) + MK-801 (0.2)
2717.4 513.9
9519.6 1097.9b
6701.0 1325.0b
F(2,26) = 10.028
P <0.001
Vehicle + vehicle
2717.4 513.9
9785.0 714.7b
9349.1 1100.6a
5618.8 609.5A
5509.0 812.4A
3852.1 720.4B
3838.5 607.6B
F(6,72) = 14.1260
P <0.0001
Vehicle + MK-801 (0.2)
36 (2.5) + MK-801 (0.2)
36 (5) + MK-801 (0.2)
36 (10) + MK-801 (0.2)
36 (20) + MK-801 (0.2)
36 (30) + MK-801 (0.2)
Vehicle + vehicle
Vehicle + MK-801 (0.2)
Haloperidol (0.5) + MK-801 (0.2)
Haloperidol (1) + MK-801 (0.2)
690.8 117.2
6139.3 755.4b
4231.8 828.9b
844.0 183.5B
F(3,35) = 22.124
P <0.0001
Figure 4. Effects of the tested compounds on the immobility time in the forced
swim test in mice.
of general locomotor activity. Its dose of 5 mg/kg producing anxio-
lytic effect did not reach statistically significant level (Table 5).
When compound 36 was given in a dose of 2.5 mg/kg, it evoked
non-specific anxiolytic-like activity because it simultaneously
modified the general activity of rats by increasing the total number
of entries, the total distance and Y ambulation (data not shown).
Diazepam (1.25 and 2.5 mg/kg), used as a reference drug, signifi-
cantly increased the time spent in the open arms, the percentage
of the time spent in the open arms, and the number of entries into
the open arms (Table 5).
Vehicle + vehicle
Vehicle + MK-801 (0.2)
Clozapine (1.25) + MK-801 (0.2)
Clozapine (2.5) + MK-801 (0.2)
902.2 123.9
4838.0 639.5b
2781.7 730.6
2503.9 654.1A
F(3,35) = 7.347
P <0.001
a
P <0.01 versus respective vehicle + vehicle group.
P <0.001 versus respective vehicle + vehicle group.
P <0.01 versus respective vehicle + MK-801 group (Bonferroni’s test).
P <0.001 versus respective vehicle + MK-801 group (Bonferroni’s test).
b
A
B
In view of the fact, that some antidepressants can modulate the
dopaminergic system, and that compounds 16 and 36 display signif-
icant affinity for dopamine D2, D3, and/or D4 receptors (Table 3), in a
successive stage we attempted to determine the antipsychotic
potential in the MK-801-induced hyperactivity test. Such dual
Table 5
Effects of the compounds 16, 36, and diazepam in the elevated plus-maze test in rats
Compd dose
(mg/kg)
Time spent in open arms (s)
mean S.E.M.
Percentage of time spent in open arms
mean S.E.M.
Open arm entries
mean S.E.M.
Percentage of open arm entries
mean S.E.M.
Vehicle
16 (2.5)
16 (5)
16 (10)
16 (20)
27.9 6.0
81.9 25.4
81.7 9.7
98.9 23.3
120.8 46.8a
F(4,33) = 2.942
P <0.05
11.5 3.0
31.0 9.2
33.4 3.6
41.0 8.9
41.7 8.9
F(4,33) = 3.075
P <0.05
5.8 1.1
6.7 1.1
25.7 2.7
34.2 1.8
10.9 1.7a
7.4 1.2
34.4 2.2
33.6 5.0
58.1 11.4c
F(4,33) = 5.422
P <0.01
2.9 0.8
F(4,33) = 5.005
P <0.01
Vehicle
36 (2.5)
36 (5)
20.2 3.2
62.3 10.3b
49.2 9.7
7.9 1.4
25.0 4.2b
19.4 3.9
29.3 2.5c
F(3,24) = 8.364
P <0.001
4.1 0.9
10.9 2.4a
8.7 0.9
23.1 3.7
36.4 7.3
32.9 2.8
40.3 3.5
F(3,24) = 2.478
ns
36 (10)
72.8 6.9c
F(3,24) = 8.013
P <0.001
11.3 1.1a
F(3,24) = 4.957
P <0.01
Vehicle
29.9 4.8
82.0 18.3b
71.7 10.9a
48.0 9.4
F(3,24) = 4.799
P <0.01
13.0 2.3
29.7 9.7a
28.5 3.9a
21.8 7.1
F(3,24) = 4.089
P <0.05
9.3 1.2
8.6 2.2
13.1 1.3
13.4 3.0
F(3,24) = 1.492
ns
26.3 2.1
63.7 11.3b
46.6 3.1
35.4 4.8
F(3,24) = 6.316
P <0.01
Diazepam (1.25)
Diazepam (2.5)
Diazepam (5)
a
b
c
P <0.05 versus respective vehicle + vehicle group (Bonferroni’s post-hoc test).
P <0.01 versus respective vehicle + vehicle group (Bonferroni’s post-hoc test).
P <0.001 versus respective vehicle + vehicle group (Bonferroni’s post-hoc test); ns—non-significant.

P. Zajdel et al. / Bioorg. Med. Chem. 20 (2012) 1545–1556
1551
Table 7
(13–26) and semi-rigid (33–36) alkylene spacer, their receptor
affinity, and the functional profile; finally, we carried out their
behavioral evaluation. The study allowed us to identify some po-
tent, mixed 5-HT2A/5-HT7 and 5-HT1A/5-HT2A/5-HT7 receptor li-
gands with additional affinity for dopamine D2, D3, and/or D4
receptors. Our lead compound 36, a 4-isoquinolinesulfonamide
with a semi-rigid alkylene spacer, classified as a multi-receptor
5-HT2A/5-HT7/D2/D3/D4 ligand, produced significant psychotropic
activity: antidepressant, anxiolytic, and antipsychotic. That com-
pound seems very promising regarding the complexity of CNS dis-
orders and the limitations of monotherapy. Selective drugs may
prove beneficial to some specific symptoms of mentioned CNS
diseases, to certain subpopulations of patients or both. However,
some network analyses of the brain and its dysfunctions suggest
that agents with multiple and complementary modes of
action are more likely to show broad-based efficacy in relation to
the core and comorbid symptoms of depression/anxiety/
schizophrenia.
Effects of the compounds 16, 36, haloperidol and clozapine on the spontaneous
locomotor activity in CD-1 mice
Compd dose (mg/kg)
Number of crossings during
60 min mean S.E.M.
Vehicle + vehicle
16 (2.5) + vehicle
16 (5) + vehicle
16 (10) + vehicle
2018.9 377.7
1836.6 255.2
1456.4 108.9
1430.9 194.2
F(3,32) = 1.1844 ns
Vehicle + vehicle
36 (10) + vehicle
36 (20) + vehicle
36 (30) + vehicle
2790.2 698.5
2080.0 348.5
1531.8 380.4
1415.6 333.2
F(3,36) = 1.830 ns
Vehicle + vehicle
1650.1 220.3
1803.6 270.0
826.8 149.9a
439.6 123.1b
F(3,36) = 10.754
P <0.0001
Haloperidol (0.25) + vehicle
Haloperidol (0.5) + vehicle
Haloperidol (1) + vehicle
Vehicle + vehicle
Clozapine (1.25) + vehicle
Clozapine (2.5) + vehicle
1185.3 292.6
867.0 197.1
1069.0 318.9
F(2,24) = 0.363 ns
6. Experimental
6.1. Materials and methods
Vehicle + vehicle
Clozapine (5) + vehicle
1197.9 153.8
446.3 175.0a
F(1,18) = 10.405
P <0.01
Organic transformations were carried out at ambient
temperature, unless indicated otherwise. Organic solvents (from
Aldrich and Chempur) were of reagent grade and were used
without purification. All other reagents were from Aldrich and Alfa
Aesar.
a
P <0.05 versus respective vehicle + vehicle group (Bonferroni’s post-hoc test).
P <0.01 versus respective vehicle + vehicle group (Bonferroni’s post-hoc test);
ns—non-significant.
b
Purity of the synthesized compounds was confirmed by TLC
performed on Merck silica gel 60 F254 aluminium sheets (Merck,
Darmstadt, Germany). Spots were detected by their absorption un-
der UV light (k = 254 nm).
activity seems very interesting, since several antipsychotic drugs
(e.g., amisulpride, aripiprazole) with
a multi-receptor profile
decrease depression and/or obsessive–compulsive disorder
symptoms.10
Analytical HPLC were run on a Waters Alliance HPLC instru-
Thus compound 36 with a multi-receptor 5-HT2A/5-HT7/D2/D3/
D4 profile, given in doses of 5–30 mg/kg, significantly inhibited the
MK-801-evoked hyperactivity in mice (Table 6). Its effect seemed
to be specific, since 36 administered in effective doses had no influ-
ence on spontaneous the locomotor activity of mice (Table 7). On
the other hand, derivative 16 produced no effect on either the
hyperactivity induced by MK-801 or spontaneous locomotor
activity in mice (Tables 6 and 7). By comparison, haloperidol
and clozapine dose-dependently and significantly attenuated the
hyperactivity evoked by MK-801; however, only clozapine
produced specific antipsychotic-like activity in that test, while hal-
operidol produced such an effect in doses which per se decreased
spontaneous locomotor activity (Tables 6 and 7).
Some interesting results of the pharmacological studies with
quinoline- and isoquinoline-sulfonamides of the long-chain aryl-
piperazine derivatives have drawn our attention. First of all, affin-
ity for the 5-HT7R proved to be an essential component for
behavioral activity of tested compounds in the mice models of
depression and anxiety. The most potent mixed 5-HT1A/5-HT2A/5-
HT7 receptor ligand 16 and the 5-HT2A/5-HT7 receptor ligand 36
displayed potential antidepressant and anxiolytic activity in the
FST and the plus-maze test, respectively. Compound 36, which also
targeted D2, D3 and D4 sites, was found to have a major additional
effect in MK-801-induced hyperlocomotor activity test in mice, a
robust model of the negative and cognitive symptoms of schizo-
phrenia.37,38 Undoubtedly, the unique properties of compound 36
resulted from the type of the azine moiety.
ment, equipped with
a
ChromolithSpeedROD column (4.6 Â
50 mm). Standard conditions were eluent system A (water/0.1%
TFA), system B (acetonitrile/0.1% TFA). A flow rate of 5 mL/min
and a gradient of (0–100)% B over 3 min were used. Detection
was performed on a PDA detector. Retention times (tR) are given
in minutes.
1H NMR spectra were recorded at 300 MHz (Varian BB 200
spectrometer) using TMS (0.00 ppm) and chloroform-d1, J values
are in hertz (Hz), and splitting patterns are designated as follows:
s (singlet), d (doublet), t (triplet), m (multiplet).
Mass spectrometry analyses: Samples were prepared in acetoni-
trile/water (10/90 v/v) mixture. The LC/MS system consisted of a
Waters Acquity UPLC, coupled to a Waters TQD mass spectrometer
(electrospray ionization mode ESI-tandem quadrupole). All the
analyses were carried out using
a Acquity UPLC BEH C18,
50 Â 2.1 mm reversed-phase column. A flow rate of 0.3 mL/min
and a gradient of (5–95)% B over 5 min was used. Eluent A:
water/0.1% HCO2H; eluent B: acetonitrile/0.1% HCO2H. Nitrogen
was used for both nebulizing and drying gas. LC/MS data were ob-
tained by scanning the first quadrupole in 0.5 s in a mass range
from 100 to 700 m/z; 8 scans were summed up to produce the final
spectrum.
Elemental analyses were found within 0.4% of the theoretical
values.
Melting points (mp) were determined with a Büchi apparatus
and are uncorrected.
Column chromatography separations were carried out on col-
umn with Merck Kieselgel 60.
The following abbreviations were used: DIEA—diisopropyleth-
ylamine; DMF—dimethylformamide; TFA—trifluoroacetic acid.
The other abbreviations used were recommended by the IUPAC-
IUB Commission (Eur. J. Biochem. 1984, 138, 9–37).
5. Conclusions
In the present study we described the synthesis of two series of
quinoline-, isoquinoline-sulfonamides containing
a
flexible

1552
P. Zajdel et al. / Bioorg. Med. Chem. 20 (2012) 1545–1556
6.2. General procedure for the preparation of compounds 13–26
(Method A)
6.2.5. N-{4-[4-(3-Chlorophenyl)-piperazin-1-yl]-butyl}-6-
chloro-3-quinolinesulfonamide (17)
The compound was prepared by the general method A in 72%
yield as oli; tR = 1.56; MS calcd for [M+H]+: C23H26ClN4O2S m/z:
492.1, found 493.3. 1H NMR (CDCl3) d (ppm) 1.64 (br s, 4H),
2.41–2.44 (t, 2H), 2.62–2.65 (m, 4H), 3.03–3.05 (m, 2H), 3.25–
3.28 (m, 4H), 6.76–6.79 (dd, 1H), 6.84–6.89 (m, 2H), 7.16–7.21 (t,
1H) 7.76–7.80 (m, 2H), 8.09–8.12 (dd, 2H), 8.52–8.53 (d, 1H,
J = 2.1 Hz), 9.19–9.20 (dd, 1H, J = 4.1 Hz, J = 2.0 Hz). Compound
17ÁHCl mp 168.9–169.9 °C. Anal. (C23H26ClN4O2SÁHCl) C, H, N.
The starting N-(
10) and N-( -aminoalkyl)-4-chlorophenylpiperazines (11, 12)
were synthesized according to the Gabriel method. A mixture of
the appropriate N-( -aminoalkyl)-3-chlorophenylpiperazine or
N-( -aminoalkyl)-4-chlorophenylpiperazine (1.2 mmol) in CH2Cl2
(7 mL), and DIEA (2.4 mmol) was cooled down (ice bath), and
azinesulfonyl (1–6) or naphthalenesulfonyl chloride (7, 8)
(1.3 mmol) was added at 0 °C in one portion. The reaction mixture
was stirred for 2–6 h under cooling. Then, the solvent was evapo-
rated and the sulfonamides were separated by column chromatog-
raphy using SiO2 and a mixture of CH2Cl2/MeOH = 9/1 or 9/0.7, as
an eluting system. Free bases were then converted into the hydro-
chloride salts by treatment of their solution in anhydrous ethanol
with 4 M HCl in dioxane.
x-aminoalkyl)-3-chlorophenylpiperazines (9,
x
x
x
6.2.6. N-{4-[4-(3-Chlorophenyl)-piperazin-1-yl]-butyl}-6-
quinolinesulfonamide (18)
The compound was prepared by the general method A in 72%
yield as yellow oil; tR = 1.19; MS calcd for [M+H]+: C23H27ClN4O2S
m/z: 458.2, found 459.3. 1H NMR (CDCl3) d (ppm) 1.63 (br s, 4H),
2.39–2.43 (t, 2H), 2.60–2.64 (m, 4H), 3.03–3.07 (m, 2H), 3.24–
3.27 (m, 4H), 6.77–6.83 (td, 1H, J = 6.2 Hz, J = 1.1 Hz), 6.86–6.87
(m, 1H), 7.15–7.2 (t, 1H) 7.63–7.68 (m, 1H), 7.82–7.89 (m, 2H),
8.16–8.19 (d, 1H), 8.55 (br s, 1H), 8.63–8.64 (d, 1H), 9.22–9.23 (d,
1H, J = 2.3 Hz). Compound 18ÁHCl mp 205.2–206.6 °C. Anal.
(C23H27ClN4O2SÁHCl) C, H, N.
6.2.1. N-{3-[4-(3-Chlorophenyl)-piperazin-1-yl]-propyl}-3-
quinolinesulfonamide (13)
The compound was prepared by the general method A in 72%
yield as yellow oil; tR = 1.21; MS calcd for [M+H]+:
C22H25ClN4O2S m/z: 444.2, found 445.2. 1H NMR (CDCl3)
d
(ppm) 1.63 (br s, 4H), 2.60–2.63 (m, 4H), 3.02–3.06 (m, 2H),
3.23–3.26 (m, 4H), 6.77–6.83 (td, 1H), 6.86–6.87 (m, 1H), 7.15–
7.19 (t, 1H) 7.63–7.68 (m, 1H), 7.82–7.89 (m, 2H), 8.16–8.19
(d, 1H), 8.55 (br s, 1H), 8.63–8.64 (d, 1H), 9.22–9.23 (d, 1H).
Compound 13ÁHCl mp 172.1–174.2 °C. Anal. (C22H25ClN4O2SÁHCl)
C, H, N.
6.2.7. N-{4-[4-(3-Chlorophenyl)-piperazin-1-yl]-butyl}-8-
quinolinesulfonamide (19)
The compound was prepared by the general method A in 72%
yield as yellow oil; tR = 1.40; MS calcd for [M+H]+: C23H27ClN4O2S
m/z: 458.2, found 459.3. 1H NMR (CDCl3) d (ppm) 1.48–1.52 (m,
4H), 2.26–2.31 (t, 2H), 2.48–2.50 (m, 4H), 2.91–2.92 (m, 2H),
3.12–3.15 (m, 4H), 6.46 (br s, 1H), 6.74–6.85 (m, 3H), 7.13–7.18
(t, 1H, J = 8.2 Hz), 7.54–7.58 (q, 1H), 7.64–7.69 (q, 1H), 8.04–8.08
(dd, 1H, J = 8.2 Hz, J = 1.5 Hz), 8.27–8.30 (d, 1H, J = 8.2 Hz,
J = 1.8 Hz), 8.43–8.46 (dd, 1H, J = 7.4 Hz, J = 1.3 Hz), 9.01–9.03 (dd,
1H, J = 4.4 Hz, J = 1.8 Hz). Compound 19ÁHCl mp 212.4–213.2 °C.
Anal. (C23H27ClN4O2SÁHCl) C, H, N.
6.2.2. N-{3-[4-(4-Chlorophenyl)-piperazin-1-yl]-propyl}-3-
quinolinesulfonamide (14)
The compound was prepared by the general method A in 77%
yield as white powder, mp 190.6–191.5 °C; tR = 1.23; MS calcd
for [M+H]+: C22H25ClN4O2S m/z: 444.2, found 445.2. 1H NMR
(CDCl3) d (ppm) 1.68–1.76 (m, 2H), 2.48–2.52 (m, 2H), 2.58–2.61
(m, 4H), 3.15–3.21 (m, 6H), 6.81–6.87 (m, 2H), 7.19–7.26 (m,
3H), 7.19–7.67 (m, 1H), 7.86–7.96 (m, 2H), 8.18–8.21 (d, J = 8.46,
1H), 8.68–8.69 (d, J = 2.31, 1H), 9.23–9.24 (d, J = 2.31, 1H).
Compound 14ÁHCl mp 186–187 °C. Anal. (C22H25ClN4O2SÁHCl) C,
H, N.
6.2.8. N-{4-[4-(4-Chlorophenyl)-piperazin-1-yl]-butyl}-3-
quinolinesulfonamide (20)
The compound was prepared by the general method A in 69%
yield as yellow oil; tR = 1.39; MS calcd for [M+H]+: C23H27ClN4O2S
m/z: 458.2, found 459.3. Compound 20ÁHCl: 1H NMR (DMSO) d
(ppm) 1.42–1.47 (m, 2H), 1.70 (br s, 2H), 2.82–2.88 (m, 2H),
2.99–3.07 (m, 4H), 3.41–3.47 (m, 2H), 3.69–3.74 (m, 4H), 6.97–
7.00 (m, 2H), 7.25–7.28 (m, 2H), 7.75–7.80 (td, 1H), 7.93–7.99
(td, 1H), 8.07–8.15 (dd, 1H), 8.24–8.26 (dd, 1H), 8.89–8.90 (dd,
1H), 9.20–9.21 (dd, 1H), 10.82 (br s, 1H). Compound 20ÁHCl Mp
190.1–192.3 °C. Anal. (C23H27ClN4O2SÁHCl) C, H, N.
6.2.3. N-{3-[4-(4-Chlorophenyl)-piperazin-1-yl]-propyl}-4-
isoquinolinesulfonamide (15)
The compound was prepared by the general method A in 72%
yield as white powder, mp 170.3–171.7 °C; tR = 1.09; MS calcd for
[M+H]+: C22H25ClN4O2S m/z: 444.2, found 445.3. 1H NMR (CDCl3)
d (ppm) 1.67–1.73 (m, 2H), 2.46–2.50 (m, 2H), 2.56–2.59 (t,
J = 4,87, 4H), 3.16–3.20 (m, 7H), 6.81–6.86 (m, 2H), 7.18–7.23 (m,
2H), 7.53–7.57 (m, 1H), 7.92–7.98 (m, 2H), 8.21–8.25 (m, 1H),
8.64 (s, 1H), 9.03–9.05 (m, 1H). Compound 15ÁHCl mp 145.2–
145.7 °C. Anal. (C22H25ClN4O2SÁHCl) C, H, N.
6.2.9. N-{4-[4-(4-Chlorophenyl)-piperazin-1-yl]-butyl}-6-
quinolinesulfonamide (21)
The compound was prepared by the general method A in 68%
yield as yellow oil; tR = 1.20; MS calcd for [M+H]+: C23H27ClN4O2S
m/z: 458.2, found 459.3. 1H NMR (CDCl3) d (ppm) 1.57–1.65 (br s,
4H), 2.37–2.42 (t, 2H), 2.59–2.63 (m, 4H), 3.02–3.06 (m, 2H),
3.16–3.20 (m, 4H), 6.79–6.85 (dt, 2H), 7.19–7.24 (dt, 2H), 7.47–
7.51 (q, 1H), 8.01–8.04 (dd, 1H), 8.09–8.12 (dd, 1H), 8.17 (s, 1H),
8.20 (s, 1H), 8.35–8.36 (d, 1H), 9.02–9.04 (dd, 1H). Compound
21ÁHCl mp 204.1–205.4 °C. Anal. (C23H27ClN4O2SÁHCl) C, H, N.
6.2.4. N-{4-[4-(3-Chlorophenyl)-piperazin-1-yl]-butyl}-3-
quinolinesulfonamide (16)
The compound was prepared by the general method A in 72%
yield as white oil, which solids upon standing; tR = 1.41; MS
calcd for [M+H]+: C23H27ClN4O2S m/z: 458.2, found 459.3. 1H
NMR (CDCl3) d (ppm) 1.63 (br s, 4H), 2.39–2.43 (t, 2H), 2.60–
2.64 (m, 4H), 3.03–3.07 (m, 2H), 3.24–3.27 (m, 4H), 6.77–6.83
(td, 1H, J = 6.2 Hz, J = 1.1 Hz), 6.86–6.87 (m, 1H), 7.15–7.2 (t,
1H) 7.63–7.68 (m, 1H), 7.82–7.89 (m, 2H), 8.16–8.19 (d, 1H),
8.55 (br s, 1H), 8.63–8.64 (d, 1H), 9.22–9.23 (d, 1H, J = 2.3 Hz).
Compound 16ÁHCl mp 183.5–185.0 °C. Anal. (C23H27ClN4O2SÁHCl)
C, H, N.
6.2.10. N-{4-[4-(4-Chlorophenyl)-piperazin-1-yl]-butyl}-7-
quinolinesulfonamide (22)
The compound was prepared by the general method A in 68%
yield as pale yellow oil; tR = 1.24; MS calcd for [M+H]+:
C
23H27ClN4O2S m/z: 458.2, found 459.3. 1H NMR (CDCl3) d (ppm)
1.60–1.62 (m, 4H), 2.38–2.42 (t, 2H), 2.60–2.64 (m, 4H), 3.04–

P. Zajdel et al. / Bioorg. Med. Chem. 20 (2012) 1545–1556
1553
3.08 (t, 2H), 3.19–3.23 (m, 4H), 6.80–6.85 (dt, 2H), 7.17–7.23 (dt,
2H), 7.51–7.55 (q, 1H), 7.88–7.94 (m, 1H), 8.19–8.23 (m, 1H),
8.61 (s, 1H), 9.01–9.03 (dd, 1H). Compound 22ÁHCl mp 223.9–
224.6 °C. Anal. (C23H27ClN4O2SÁHCl) C, H, N.
presence of TEA (21.5 mmol) the boiling mixture of THF/toluene
(5 mL/10 mL) for 20 h. After solvent evaporation the crude product
was purified on silica gel column chromatography (CH2Cl2/MeOH
9/0.5, v/v) to yield Boc-protected piperidine 31 and 32. For the next
stage the products were converted into their TFA salts and were iso-
lated as white foams.
6.2.11. N-{4-[4-(4-Chlorophenyl)-piperazin-1-yl]-butyl}-4-
isoquinolinesulfonamide (23)
The compound was prepared by the general method A in 66%
yield as white powder, mp 132.8–133.2 °C; tR = 1.19; MS calcd
for [M+H]+: C23H27ClN4O2S m/z: 458.2, found 459.3. 1H NMR
(CDCl3) d (ppm) 1.60–1.62 (s, 4H), 2.41–2.43 (m, 2H), 2.64–2.67
(m, 4H), 3.03 (s, 2H), 3.25–3.28 (m, 4H), 6.83–6.88 (m, 2H), 7.19–
7.27 (m, 2H), 7.68–7.78 (m, 2H), 8.06–8.09 (m, 1H), 8.50 (s, 1H),
8.64–8.67 (m, 1H), 9.09 (s, 1H), 9.38 (s, 1H). Compound 23ÁHCl
mp 198.1–198.8 °C. Anal. (C23H27ClN4O2SÁHCl) C, H, N.
6.3.1. 4-(Toluene-4-sulfonyloxymethyl)-piperidine-1-carboxylic
acid tert-butyl ester (29)
The compound was prepared in 65% yield as white powder;
tR = 1.95; MS calcd for [M+H]+: C18H27NO5S m/z: 370.2, found
370.4; mp 84.0–84.2 °C. 1H NMR (CDCl3) d (ppm) 1.02–1.16 (m,
2H), 1.43 (s, 9H), 1.62–1.66 (m, 2H), 1.77–1.86 (m, 1H), 2.45 (s,
3H), 2.60–2.69 (t, J = 12.6 Hz, 2H), 3.84–3.86 (d, J = 6.41 Hz, 2H),
4.06–4.10 (d, J = 11.8 Hz, 2H), 7.36–7.73 (d, J = 7.9 Hz, 2H), 7.76–
7.79 (dd, J = 6.7 Hz, 2H).
6.2.12. N-{5-[4-(4-Chlorophenyl)-piperazin-1-yl]-pentyl}-3-
quinolinesulfonamide (24)
6.3.2. 4-[2-(Toluene-4-sulfonyloxy)-ethyl]-piperidine-1-
carboxylic acid tert-butyl ester (30)
The compound was prepared by the general method A in 72%
yield as a pale oil; tR = 1.31; MS calcd for [M+H]+: C24H29ClN4O2S
m/z: 472.2, found 473.3. 1H NMR (CDCl3) d (ppm) 1.25–1.38 (m,
4H), 1.42–1.59 (m, 4H), 2.29–2.36 (m, 2H), 2.51–2.54 (m, 4H),
3.06–3.15 (m, 5H), 6.79–6.84 (m, 2H), 7.16–7.22 (m, 2H), 7.67–
7.72 (m, 1H), 7.86–7.95 (m, 2H), 8.18–8.21 (d, 1H, J = 8.72), 8.69–
8.70 (d, 1H, J = 2.05), 9.25–9.26 (d, 1H, J = 2.31). Compound 24ÁHCl
mp 145.3–146.0 °C. Anal. (C24H29ClN4O2SÁHCl) C, H, N.
The compound was prepared in 65% yield as white powder;
tR = 1.99; MS calcd for [M+H]+: C19H29NO5S m/z: 383.2, found
384.1; mp 61.2–61.6 °C. 1H NMR (CDCl3) d (ppm) 0.97–1.09 (m,
2H), 1.44 (s, 9H), 1.46–1.60 (m, 5H), 2.45 (s, 3H), 2.60–2.65 (m,
2H), 4.01–4.09 (m, 4H), 7.34–7.36 (d, J = 9.2 Hz, 2H), 7.78–7.81
(dd, J = 6.7 Hz, J = 1.79 Hz, 2H).
6.3.3. 4-[4-(4-Chloro-phenyl)-piperazin-1-ylmethyl]-piperidine-
1-carboxylic acid tert-butyl ester (31)
6.2.13. N-{4-[4-(4-Chlorophenyl)-piperazin-1-yl]-butyl}-1-
naphthalenesulfonamide (25)
The compound was prepared in 64% yield as white powder;
tR = 1.34; MS calcd for [M+H]+: C21H32ClN3O2 m/z: 393.2, found
394.4; mp 115.9–116.2 °C. 1H NMR (CDCl3) d (ppm) 1.02–1.15
(m, 2H), 1.45 (s, 9H), 1.60–1.67 (m, 1H), 1.69–176 (m, 2H), 2.21–
2.31 (d, J = 6.9 Hz, 2H), 2.53–2.56 (m, 4H), 2.65–2.74 (m, 2H),
3.12–3.16 (m, 4H), 4.08–4.11 (d, J = 9.7 Hz, 2H), 6.80–6.85 (m,
2H), 7.17–7.22 (m, 2H). Anal. (C21H32ClN3O2) C, H, N.
The compound was prepared by the general method A in 78%
yield as pale yellow oil; tR = 1.57; MS calcd for [M+H]+:
C
24H28ClN3O2S m/z: 457.2, found 458.4. 1H NMR (CDCl3)
d
(ppm) 1.39–1.44 (m, 2H), 1.67 (b s, 2H), 2.76–2.83 (m, 2H),
3.01–3.10 (m, 6H), 3.41–3.35 (m, 2H), 3.81–3.85 (m, 2H), 6.84–
6.87 (dd, 1H), 6.91–6.95 (dd, 1H), 7.01–7.03 (br, 1H), 7.22–7.27
(t, 1H), 7.64–7.73 (m, 2H), 7.79–7.84 (m, 2H), 8.03–8.06 (dd,
1H), 8.12–8.17 (m, 2H), 8.43 (dd, 1H). Compound 25ÁHCl mp
199.7–200.4 °C. Anal. (C24H28ClN3O2SÁHCl) C, H, N.
6.3.4. 4-[4-(4-Chloro-phenyl)-piperazin-1-ylethyl]-piperidine-1-
carboxylic acid tert-butyl ester (32)
The compound was prepared in 67% yield as white powder;
tR = 1.36; MS calcd for [M+H]+: C22H34ClN3O2 m/z: 407.2, found
408.3; mp 92.2–92.4 °C. 1H NMR (CDCl3) d (ppm) 1.12–1.18 (m,
2H), 1.20–1.32 (m, 1H), 1.45 (s, 11H), 1.64–1.68 (d, J = 12.3 Hz,
2H), 2.41–2.45 (m, 2H), 2.60–2.72 (m, 6H), 3.15–3.18 (m, 4H),
4.05–4.23 (m, 2H), 6.81–6.85 (d, J = 8.9 Hz, 2H), 7.18–7.26 (m,
2H) Anal. (C22H34ClN3O2) C, H, N.
6.2.14. N-{4-[4-(4-Chlorophenyl)-piperazin-1-yl]-butyl}-2-
naphthalenesulfonamide (26)
The compound was prepared by the general method A in 72%
yield as yellow oil; tR = 1.55; MS calcd for [M+H]+: C24H28ClN3O2S
m/z: 457.2, found 457.9. 1H NMR (CDCl3) d (ppm) 1.35–1.38 (m,
2H), 1.53–1.56 (m, 2H), 2.77–2.83 (m, 2H), 2.98 (b s, 4H), 3.06–
3.10 (m, 2H), 3.38–3.46 (m, 2H), 3.81–3.85 (m, 2H), 6.84–6.87
(dd, 1H), 6.92–6.97 (dd, 1H), 7.02–7.04 (t, 1H), 7.21–7.28 (t, 1H),
7.62–7.75 (m, 2H), 8.02–8.13 (m, 4H), 8.21–8.27 (dd, 1H), 8.62–
8.66 (dd, 1H). Compound 26ÁHCl mp 218.6–219.9 °C. Anal.
(C24H28ClN3O2SÁHCl) C, H, N.
6.4. General procedure for the preparation of compounds and
33–36 (Method B)
A mixture of 1-(4-chlorophenyl)-4-piperidin-4-ylmethyl-piper-
azine (31) or 1-(4-chloro-phenyl)-4-piperidin-4-ylethyl-piperazine
(32) (1.2 mmol) in CH2Cl2 (7 mL), and DIEA (3.6 mmol) was cooled
down (ice bath), and azinesulfonyl (1.3 mmol) was added at 0 °C in
one portion. The reaction mixture was stirred for 2–6 h under cool-
ing. Then, the solvent was evaporated and the sulfonamides were
separated by column chromatography using SiO2 and a mixture
of CH2Cl2/MeOH = 9/0.5, as an eluting system. Free bases were then
converted into the hydrochloride salts by treatment of their solu-
tion in anhydrous ethanol with 4 M HCl in dioxane.
6.3. Synthesis of 1-(4-chloro-phenyl)-4-piperidin-4-ylmethyl-
piperazine (31) and 1-(4-chlorophenyl)-4-piperidin-4-ylethyl-
piperazine (32)
Boc-piperidinemethanol (27) or Boc-piperidineethanol (28)
(23 mmol) dissolved in pyridine (50 mL) and cooled down under
nitrogen. Then a tosyl chloride (27,87 mmol) was added portion-
wise. The was carried out for 3 h on bath-ice, then warm to room
temperature and stirred for additional 10 h. The reaction mixture
was extracted with CH2Cl2 (150 mL) and the organic phase was
washed with 1 M KHSO4 (4 Â 50 mL), water, brine and dried over
Na2SO4. The tosyl derivatives (29, 30) were separated by column
chromatography using SiO2 and CH2Cl2 followed by CH2Cl2/
MeOH = 9/0.1. Next tosyl derivatives (2.44 mmol) were reacted
with 4-chlorophenylpiperazine (2 mmol) by heating them in the
6.4.1. 3-{4-[4-(4-Chlorophenyl)-piperazin-1-ylmethyl]-
piperidine-1-sulfonyl}-quinoline (33)
The compound was prepared by the general method B starting
from 31 in 62% yield as white powder mp 179.5–180.2 °C;
tR = 1.30; MS calcd for [M+H]+: C25H29ClN4O 2S
484.2, found
m/z:
485.3. 1H NMR (CDCl3) d (ppm) 1.26–1.42 (m, 3H), 1.84–1.88 (d,

1554
P. Zajdel et al. / Bioorg. Med. Chem. 20 (2012) 1545–1556
2H), 2.18–2.20 (d, 2H), 2.34–2.42 (m, 2H), 2.47–2.49 (m, 4H), 3.01–
3.07 (t, 4H), 3.90–3.94 (d, 2H), 6.78–6.81 (m, 2H), 7.16–7.19 (m,
2H), 7.68–7.73 (m, 1H), 7.88–7.99 (m, 2H), 8.20–8.22 (d, 1H),
8.61–8.62 (d, J = 2.1 Hz, 1H), 9.18–9.19 (d, J = 2.3 Hz, 1H). Com-
pound 33ÁHCl mp 244.2–254.8 °C. Anal. (C25H29ClN4O2SÁHCl) C, H,
N.
were tested in 5 concentrations at 10À4–10À9 in the h5-HT7 antag-
onist effect. For the antagonists, the apparent dissociation constants
(KB) were calculated using the modified Cheng Prusoff equation
(KB = IC50/(1+(A/EC50A)), where A = concentration of reference ago-
nist in the assay, and EC50A = EC50 value of the reference agonist).
6.6. In vivo pharmacology
6.4.2. 7-{4-[4-(4-Chlorophenyl)-piperazin-1-ylmethyl]-
piperidine-1-sulfonyl}-quinoline (34)
6.6.1. Subjects
The compound was prepared by the general method B starting
from amine 31 in 71% yield as white powder mp 134.5–135.0 °C;
tR = 1.26; MS calcd for [M+H]+: C25H29ClN4O2S m/z: 484.2, found
485.3. 1H NMR (CDCl3) d (ppm) 1.19–1.43 (m, 3H), 1.81–1.85 (d,
J = 11.54, 2H), 2.17–2.20 (d, J = 6.41, 2H), 2.31–2.39 (m, 2H), 2.47
(s, 4H), 3.08 (s, 4H), 3.89–3.93 (d, J = 12.0 Hz, 2H), 7.15–7.19 (m,
2H), 7.26–7.27 (m, 2H), 7.55–7.59 (m, 1H), 7.85–7.89 (m, 1H),
7.97–8.00 (d, J = 8.72, 1H), 8.24–8.27 (d, J = 7.7 Hz, 1H), 8.60 (s,
1H), 9.05–9.07 (m, 1H). Compound 34ÁHCl mp 251.2–252.0 °C.
Anal. (C25H29ClN4O2SÁHCl) C, H, N.
The experiments were performed on male Swiss albino mice
(22–26 g) purchased from a licensed breeder Staniszewska (Ilkow-
ice, Poland) or male CD-1 mice (accredited animal facility Jagiello-
nian University Medical College Kraków, Poland) and mice were
kept in groups of ten to Makrolon type 3 cages (dimensions
26.5 Â 15 Â 42 cm). Male Wistar rats weighing 205–225 g ob-
tained from accredited animal facility Jagiellonian University Med-
ical College (Kraków, Poland) were housed in polycarbonate
Makrolon type 3 cages (dimensions 26.5 Â 15 Â 42 cm) in groups
of four. All animals were kept in an environmentally controlled
rooms (ambient temperature 22 2 °C; relative humidity 50–
60%; 12:12 light–dark cycle, lights on at 8:00). They were allowed
to acclimatize with the environment for one week before com-
mencement of the experiments. Standard laboratory food (Ssniff
M-Z) and filtered water were freely available. All the experimental
procedures were approved by the I Local Ethics Commission at the
Jagiellonian University in Kraków.
6.4.3. 3-(4-{2-[4-(4-Chlorophenyl)-piperazin-1-yl]-ethyl}-
piperidine-1-sulfonyl)-quinoline (35)
The compound was prepared by the general method B starting
from amine 32 in 71% yield as white powder mp 174.0–174.9 °C;
tR = 1.34; MS calcd for [M+H]+: C26H31ClN4O2S m/z: 498.2, found
499.3. 1H NMR (CDCl3) d (ppm) 1.25–1.48 (m, 4H), 1.69 (s, 1H),
1.76–1.79 (m, 2H), 2.32–2.40 (m, 4H), 2.51–2.54 (t, J = 4.8 Hz,
4H), 3.10–3.13 (m, 4H), 3.87–3.91 (d, J = 11.8 Hz, 2H), 6.78–6.83
(m, 2H), 7.15–7.25 (m, 2H), 7.68–7.73 (m, 1H), 7.87–7.98 (m,
2H), 8.19–8.22 (d, J = 8.21, 1H), 8.60–8.61 (d, J = 2.0 Hz, 1H),
9.17–9.18 (d, J = 2.0 Hz, 1H). Compound 35ÁHCl mp 251.3–
252.0 °C. Anal. (C26H31ClN4O2SÁHCl) C, H, N.
6.6.2. Experimental procedures
All the experiments were conducted in the light phase between
09.00 and 14.00 h. Each experimental group consisted of 5–10 ani-
mals/dose, and the animals were used only once in each test. The
experiments were performed by an observer unaware of the treat-
ment administered.
6.4.4. 4-(4-{2-[4-(4-Chlorophenyl)-piperazin-1-yl]-ethyl}-
piperidine-1-sulfonyl)-isoquinoline (36)
6.6.3. Lower lip retraction (LLR) in rats
The compound was prepared by the general method B starting
from amine 32 in 73% yield as white powder mp 144.5–145.3 °C;
tR = 1.31; MS calcd for [M+H]+: C26H31ClN4O2S m/z: 498.2, found
499.3. 1H NMR (CDCl3) d (ppm) 1.25–1.32 (m, 4H), 1.40–1.45 (m,
2H), 1.65 (s, 1H), 1.72–1.76 (d, J = 10.3 Hz, 2H), 2.32–2.37 (m,
2H), 2.51–2.56 (m, 4H), 3.10–3.13 (m, 4H), 3.89–3.93 (d,
J = 12.0 Hz, 2H), 6.78–6.83 (m, 2H), 7.16–7.21 (m, 2H), 7.72–7.77
(m, 1H), 7.85–7.91 (m, 1H), 8.08–8.11 (d, J = 8.2 Hz, 1H), 8.70–
8.73 (d, J = 8.7 Hz, 1H), 9.07 (s, 1H), 9.40 (s, 1H). Compound 36ÁHCl
mp 221.8–222.3 °C. Anal. (C26H31ClN4O2SÁHCl) C, H, N.
The LLR was assessed according to the method of Berendsen
et al.28 The rats were individually placed in cages
(30 Â 25 Â 25 cm) and were scored three times (at 15, 30 and
45 min after the tested compound or 8-OH-DPAT administration
as follows: 0 = lower incisors not visible, 0.5 = partly visible,
1 = completely visible. The sum at maximum score, amounted to
3 for each rat. The effect of the investigated compound on the
LLR induced by 8-OH-DPAT (1 mg/kg) was assessed in a separate
experiment. The investigated compound was administered
45 min before 8-OH-DPAT, and the animals were scored at 15, 30
and 45 min after 8-OH-DPAT administration.
6.5. In vitro pharmacology
6.6.4. Head twitch response in Swiss albino mice
6.5.1. Radioligand binding experiments
In order to habituate mice to the experimental environment,
each animal was randomly transferred to a 12 (diameter  20 cm
(height) glass cage, lined with sawdust 20 min before the treat-
ment. Head twitches in mice were induced by ( )DOI (2.5 mg/
kg). Immediately after treatment, the number of head twitches
was counted during 20 min.29 ID50 (the dose inhibiting the head
twitches in mice by 50%) was calculated using Graph Pad Prism 5
Software.
Compounds were tested in competition binding experiments
for native 5-HT1A, 5-HT2A receptors, and dopamine D2 as well as
for cloned human 5-HT6 and 5-HT7 receptors, according to the pre-
viously published procedures.20,22,23,27 The binding parameters are
summarized in Table 1-SM. Following incubation, the receptor
preparations were rapidly filtered under vacuum through GF/B
glass fiber filters; the filters were washed extensively with an ice
cold buffer using a harvester. Bound radioactivity was measured
by scintillation counting using a liquid scintillation cocktail. Com-
pounds (7–9 concentrations) were tested in triplicate. The inhibi-
tion constants (Ki) were calculated from the Cheng–Prushoff
equation.39 Results are expressed as means of at least three sepa-
rate experiments.
6.6.5. Apomorphine-induced climbing behavior in Swiss albino
mice
For observation, mice were placed in separate cages with walls
made of metal bars. Apomorphine (3 mg/kg) was injected 10 min
after the drugs. Twenty minutes after injection of apomorphine,
time of climbing was determined for 2 min. Climbing time was de-
fined as the period during which the animal held the 2, 3 or 4 paws
on the wall. ID50 (the dose inhibiting climbing behavior in mice by
50%) was calculated using Graph Pad Prism 5 Software.
6.5.2. Effects on adenylate cyclase activity
Adenylate cyclase activity is expressed as the percentage of the
maximal effect obtained with 300 nM serotonin. The compounds

P. Zajdel et al. / Bioorg. Med. Chem. 20 (2012) 1545–1556
1555
6.6.6. Forced swim test in Swiss albino mice
ing. Control animals received a vehicle injection according to the
same schedule.
The experiment was carried out according to the method of Por-
solt et al.30 Briefly, mice were individually placed in a glass cylinder
(25 cm high; 10 cm in diameter) containing 6 cm of water main-
tained at 23–25 °C, and were left there for 6 min. A mouse was re-
garded as immobile when it remained floating on the water,
making only small movements to keep its head above it. The total
duration of immobility was recorded during the last 4 min of a 6-
min test session.
6.6.12. Statistics
All the data are presented as the mean SEM. The statistical sig-
nificance of the results was evaluated by a one-way ANOVA, fol-
lowed by Bonferroni Comparison Test.
Acknowledgments
´
6.6.7. Locomotor activity in mice
The authors wish to thank Mr. Andrzej Miodonski for his tech-
The locomotor activity was recorded with an Opto M3 multi-
channel activity monitor (MultiDevice Software v.1.3, Columbus
Instruments). The Swiss albino mice were individually placed in
plastic cages (22 Â 12 Â 13 cm), and then the crossings of each
channel (ambulation) were counted from 2 to 6 min, that is the
time equal to the observation period in the forced swim test and
during 30-min experimental sessions. The CD-1 mice were individ-
ually placed in plastic cages (22 Â 12 Â 13 cm) for 30 min habitua-
tion period, and then ambulation were counted during 1 h with
data recording every 5 min. The cages were cleaned up with 70%
ethanol after each mouse.
nical assistance. This study was partly supported by the Polish
Ministry of Science and Higher Education (MNiSW), Grant No.
N N405 378437 and Funds for Statutory Activity of Jagiellonian
University Medical College. Radioligand binding experiments were
financially supported by the Norwegian Financial Mechanism as
part of the Polish–Norwegian Research Fund, Grant No. PNRF–
103–AI-1/07.
Supplementary data
Supplementary data associated with this article can be found, in
the online version, at doi:10.1016/j.bmc.2011.12.039.
6.6.8. MK-801-induced hyperlocomotor in CD-1 mice
The locomotor activity was recorded according to the method
described above.
References and notes
1. Carr, G. V.; Lucky, I. Psychopharmacology 2011, 213, 265.
2. Hedlund, P. B.; Sutcliffe, J. G. Trends Pharmacol. Sci. 2004, 25, 418.
3. Roth, B. L.; Craigo, S. C.; Choudhary, M. S.; Uluer, A.; Monsma, F. J., Jr.; Shen, Y.;
Meltzer, H. Y.; Sibley, D. R. J. Pharmacol. Exp. Ther. 1994, 268, 1403.
4. Hedlund, P. B. Psychopharmacology 2009, 206, 345.
5. Roberts, A. J.; Hedlund, P. B. Hippocampus 2011. doi:10.1002/hipo.20938.
6. Wesołowska, A.; Nikiforuk, A.; Stachowicz, K.; Tatarczyn´ ska, E.
Neuropharmacology 2006, 51, 578.
7. Hedlund, P. B.; Huitron-Resendiz, S.; Henriksen, S. J.; Sutcliffe, J. G. Biol.
Psychiatry 2005, 58, 831.
8. Abbas, A. I.; Hedlund, P. B.; Huang, X. P.; Tran, T. B.; Meltzer, H. Y.; Roth, B. L.
Psychopharmacology 2009, 205, 119.
9. Sarkisyan, G.; Roberts, A. J.; Hedlund, P. B. Behav. Brain Res. 2010, 209, 99.
10. Leucht, S.; Corves, C.; Arbter, D.; Engel, R. R.; Li, C.; Davis, J. M. Lancet 2009, 373,
31.
11. Lovell, P. J.; Bromidge, S. M.; Dabbs, S.; Duckworth, D. M.; Forbes, I. T.; Jennings,
A. J.; King, F. D.; Middlemiss, D. N.; Rahman, S. K.; Saunders, D. V.; Collin, L. L.;
Hagan, J. J.; Riley, G. J.; Thomas, D. R. J. Med. Chem. 2000, 43, 342.
12. Raubo, P.; Beer, M. S.; Hunt, P. A.; Huscroft, I. T.; London, C.; Stanton, J. A.;
Kulagowski, J. J. Bioorg. Med. Chem. Lett. 2006, 16, 1255.
13. Kikuchi, C.; Ando, T.; Watanabe, T.; Nagaso, H.; Okuno, M.; Hiranuma, T.;
Koyama, M. J. Med. Chem. 2002, 45, 2197.
14. Vermeulen, E. S.; van Smeden, M.; Schmidt, A. W.; Sprouse, J. S.; Wikström, H.
V.; Grol, C. J. J. Med. Chem. 2004, 47, 5451.
6.6.9. Elevated plus-maze in rats
Plus-maze apparatus (an automated device produced by Camp-
den Instruments Ltd, UK) made of durable, high density, non por-
ous black plastic, elevated to a height of 50 cm, consisted of two
open arms (50 Â 10 cm) and two closed arms (50 Â 10 cm, and
30 cm high walls), arranged so that the two arms of each type were
opposite each other. Floor of the plus-maze was made of infrared
transparent material what means that there are no visible sensors.
The plus-maze was placed in a darkened room, and the center of
the apparatus was illuminated with a 25 W electric bulb hanging
100 cm above. Plus-maze apparatus was connected to PC software
by control chassis. Each rat was gently placed in the center of the
plus-maze, facing one of the closed arms, immediately after a 5-
min adaptation period in a plastic black box (60 Â 60 Â 35 cm).
During a 5-min test period, automated Motor Monitor System re-
corded the number of entries into the closed and open arms, the
time spent in either type of the arms. After each trial the maze
was wiped clean.
15. Leopoldo, M.; Lacivita, E.; Berardi, F.; Perrone, R.; Hedlund, P. B. Pharmacol.
Ther. 2011, 129, 120.
´
16. Zajdel, P.; Subra, G.; Bojarski, A. J.; Duszynska, B.; Pawłowski, M.; Martinez, J.
6.6.10. General locomotor activity in rats
Bioorg. Med. Chem. 2005, 13, 3029.
17. Medina, R. A.; Sallander, J.; Benhamu, B.; Porras, E.; Campillo, M.; Pardo, L.;
Lopez-Rodriguez, M. L. J. Med. Chem. 2009, 52, 2384.
The experiment was performed using plus-maze apparatus (an
automated device produced by Campden Instruments Ltd, UK)
(please see above). During a 5-min test period (i.e., the time equal
to the observation period in the elevated plus-maze test), auto-
mated Motor Monitor System recorded the total entries, the total
distance, X and Y ambulations; all parameters giving evidence to
general locomotor activity, competing behavior which should be
excluded in case of effective anxiolytic doses.
18. Zajdel, P.; Subra, G.; Bojarski, A. J.; Duszyn
´ ska, B.; Martinez, J.; Pawłowski, M.
Bioorg. Med. Chem. Lett. 2009, 19, 4827.
}
19. Volk, B.; Barkóczy, J.; Hegedus, E.; Udvari, S. Z.; Gacsályi, I.; Mezei, T.; Pallagi,
K.; Kompagne, H.; Lévay, G.; Egyed, A.; Hársing, L. G., Jr.; Spedding, M.; Simig, G.
J. Med. Chem. 2008, 51, 2522.
20. Zajdel, P.; Marciniec, K.; Mas´lankiewicz, A.; Paluchowska, M.; Satała, G.;
Partyka, A.; Jastrzebska-Wie˛sek, M.; Wróbel, M.; Wesołowska, A.; Duszyn´ ska,
B.; Bojarski, A. J.; Pawłowski, M. Bioorg. Med. Chem. 2011, 19, 6750.
´
21. Marciniec, K.; Maslankiewicz, A.; Pawłowski, M.; Zajdel, P. Heterocycles 2007,
71, 1975.
6.6.11. Drugs
´
22. Bojarski, A. J.; Cegła, M. T.; Charakchieva-Minol, S.; Mokrosz, M. J.; Mackowiak,
The following drugs were used: imipramine (hydrochloride,
Sigma), diazepam (Polfa, Poland), MK-801 (hydrogen maleate, Sig-
ma) and tested compounds: 16, 17, 20, 35, 36. Imipramine and MK-
801 were dissolved in distilled water; remaining compounds were
suspended in a 1% aqueous solution of Tween 80 immediately be-
fore administration. All the compounds were administered intra-
peritoneally at a volume of 10 ml/kg (mice) or 2 ml/kg (rats) and
were given 30 min before the test, excluding diazepam and MK-
801 which were injected 60 and 15 min, respectively, before test-
M.; Misztal, S.; Mokrosz, J. L. Pharmazie 1993, 48, 289.
23. Bojarski, A. J.; Paluchowska, M. H.; Duszyn´ ska, B.; Kłodzin´ ska, A.; Tatarczyn´ ska,
E.; Chojnacka-Wójcik, E. Bioorg. Med. Chem. 2005, 13, 2293.
24. Paluchowska, M. H.; Bugno, R.; Tatarczyn´ ska, E.; Nikiforuk, A.; Lenda, T.;
Chojnacka-Wójcik, E. Bioorg. Med. Chem. 2007, 15, 7116.
25. MacKenzie, R. G.; VanLeeuwen, D.; Pugsley, T. A.; Shih, Y. H.; Demattos, S.;
Tang, L.; Todd, R. D.; O’Malley, K. L. Eur. J. Pharmacol. 1994, 266, 79.
26. Van Tol, H. H.; Wu, C. M.; Guan, H. C.; Ohara, K.; Bunzow, J. R.; Civelli, O.;
Kennedy, J.; Seeman, P.; Niznik, H. B.; Jovanovic, V. Nature 1992, 358, 149.
27. Adham, N.; Zgombick, J. M.; Bard, J.; Branchek, T. A. J. Pharmacol. Exp. Ther.
1998, 287, 508.

1556
P. Zajdel et al. / Bioorg. Med. Chem. 20 (2012) 1545–1556
28. Berendsen, H. H.; Jenck, F.; Broekkamp, C. L. Pharmacol. Biochem. Behav. 1989,
33, 821.
29. Darmani, N. A.; Martin, B. R.; Pandey, U.; Glennon, R. A. Pharmacol. Biochem.
Behav. 1990, 36, 901.
30. Porsolt, R. D.; Bertin, A.; Jalfre, M. Arch. Int. Pharmacodyn. Ther. 1977, 229, 327.
31. Chen, J.; Ding, K.; Levant, B.; Wang, S. Bioorg. Med. Chem. Lett. 2006, 16, 443.
32. Graulich, A.; Leonard, M.; Resimont, M.; Huang, X.-P.; Roth, B. L.; Liegeois, J.-F.
Aust. J. Chem. 2010, 63, 56.
33. Lober, S.; Hubner, H.; Tschammer, N.; Gmeiner, P. Trends Pharmacol. Sci. 2011,
32, 148.
V.; Fiorini, I.; Novellino, E.; Cagnotto, A.; Mennini, T.; Sandager-Nielsen, K.;
Andreasen, J. T.; Scheel-Kruger, J.; Mikkelsen, J. D.; Fattorusso, C. J. Med. Chem.
2009, 52, 151.
35. Zajdel, P.; Subra, G.; Bojarski, A. J.; Duszyn´ ska, B.; Tatarczyn´ ska, E.; Nikiforuk,
A.; Chojnacka-Wójcik, E.; Pawłowski, M.; Martinez, J. Bioorg. Med. Chem. 2007,
15, 2907.
36. Wesołowska, A. Pharmacol. Rep. 2010, 62, 564.
37. Carlsson, M.; Carlsson, A. Trends Neurosci. 1990, 13, 272.
38. Jentsch, J. D.; Roth, R. H. Neuropsychopharmacology 1999, 20, 201.
39. Cheng, Y.; Prusoff, W. H. Biochem. Pharmacol. 1973, 22, 3099.
34. Butini, S.; Gemma, S.; Campiani, G.; Franceschini, S.; Trotta, F.; Borriello, M.;
Ceres, N.; Ros, S.; Coccone, S. S.; Bernetti, M.; De Angelis, M.; Brindisi, M.; Nacci,