Exploration of the amine terminus in a novel series of 1,2,4-Triazolo-3-yl- azabicyclo[3.1.0]hexanes as selective dopamine D3 receptor antagonists

Article abstract of DOI:10.1021/jm100832d

A novel series of 1,2,4-triazol-3-yl-azabicyclo[3.1.0]hexanes with high affinity and selectivity for the DA D₃ receptor and excellent pharmacokinetic profiles was recently reported. We also recently discussed the role of the linker associated with the triazole moiety. In this manuscript, we are reporting a detailed exploration of the region of the receptor interacting with the amine terminus of the scaffold wherein SAR and developability data associated with these novel templates was undertaken.

Full text of DOI:10.1021/jm100832d

J. Med. Chem. 2010, 53, 7129–7139 7129
DOI: 10.1021/jm100832d
Exploration of the Amine Terminus in a Novel Series of 1,2,4-Triazolo-3-yl-azabicyclo[3.1.0]hexanes
as Selective Dopamine D3 Receptor Antagonists
Fabrizio Micheli,*,§,† Luca Arista,# Barbara Bertani,§,† Simone Braggio,§,† Anna Maria Capelli,§,‡ Susanna Cremonesi,§,†
Romano Di-Fabio,§,† Giacomo Gelardi,§,† Gabriella Gentile,§,† Carla Marchioro,§,‡ Alessandra Pasquarello,§,†
Stefano Provera,§,‡ Giovanna Tedesco,§,‡ Luca Tarsi,§,† Silvia Terreni,§,† Angela Worby, ,‡ and Christian Heidbreder^
†Neurosciences Centre of Excellence, and ‡Molecular Discovery Research, §GlaxoSmithKline Medicines Research Centre, Via Fleming 4,
37135 Verona, Italy, NFSP, Harlow, U.K., ^Reckitt Benckiser Pharmaceuticals, Richmond, Virginia 23235, and #Novartis Institute Research,
Basel, Switzerland
Received July 5, 2010
A novel series of 1,2,4-triazol-3-yl-azabicyclo[3.1.0]hexanes with high affinity and selectivity for the DA
D3 receptor and excellent pharmacokinetic profiles was recently reported. We also recently discussed the
role of the linker associated with the triazole moiety. In this manuscript, we are reporting a detailed
exploration of the region of the receptor interacting with the amine terminus of the scaffold wherein
SAR and developability data associated with these novel templates was undertaken.
Introduction
(Figure 1) was refined.14 A schematic representation of this
refined version is reported in Figure 3A with all the compounds
reported in Figure 1 fitted in the model; Figure 3B represents
only the 1,2,4-triazol-3-yl- azabicyclo[3.1.0]hexane scaffold
(1). Further details on the model construction are available
in the Supporting Information.
Growing evidence arising from preclinical models of sub-
stance dependence suggests that selective DA D3 receptor
antagonists might be a potential approach for the pharma-
cotherapeutic management of substance dependence and
addiction.1-6 The data collected thus far suggest that selective
DAD3 receptor antagonistsare efficacious in disrupting drug-
associated cue-induced craving, hence preventing reinstate-
ment of drug-seeking behavior. These findings have greatly
contributed to the interest of medicinal chemists in developing
new and highly selective ligands.
Despite the difficulty of understanding a three-dimensional
arrangement that is plotted in a two-dimensional space, it is
becoming evident that one of the hydrophobic regions was
removed from the original model and that the aromatic region
has now a slightly different positioning with respect to the
positiveionizable region. Considering that the aim ofthe work
was the identification of new amines that could potentially
replace the azabicyclo[3.1.0]hexane system of scaffold 1, it was
important to focus the modeling work on this specific area.
The first attempt was to design an “expanded” ring system
with respect to the azabicyclo[3.1.0]hexane that could, how-
ever, maintain the same distance between the basic nitrogen
and the centroid of the aromatic system. Accordingly, the
regioisomeric 1-phenyl-3-azabicyclo[4.1.0]heptane (6, Figure4A)
and 6-phenyl-3-azabicyclo[4.1.0]heptane (7, Figure 4A)
templates and the 1-phenyl-4-azabicyclo[5.1.0]octane (8,
Figure 4A) scaffold were designed. Figure 4B shows an
example of a single enantiomer of each of the fragments 6
and 7. All these structures tend to fit quite well within these
regions of the pharmacophore model in terms of key interac-
tion points. Nonetheless, it is worth reporting that for all these
new scaffolds, a portion of their structure cannot fully overlap
(in terms of van der Waal’s volumes) with the original smaller
template; therefore, a potentially forbidden region might arise
because of a steric clash within the active site of the receptor.
We have recently reported7 a new series of 1,2,4-triazol-3-
yl- azabicyclo[3.1.0]hexanes endowed with high affinity and
selectivity at the DA D3 receptor (1, Figure 1). These com-
pounds have an excellent pharmacokinetic (PKa) profile and
show efficacy in animal models of drug dependence. We have
also recently explored8 the role of the thiotriazole system by
modifying the linker (2, Figure 1) and replacing the sulfur
atom with oxygen and carbon. Also in this case, compounds
endowed with good potency and a favorable PK profile were
identified. In this rigorous exploration of selective DA D3
receptor antagonists, the next logical step was to analyze the
amine portion of the molecule. Considering that a benzazepine
(BAZ) template9 (3, Figure 1) and fused BAZ scaffolds10,11 (4,
5, Figure 1) were available in our collection and that selective
compounds were also reported by others,5 the in-house
available pharmacophore model (Figure 2) mainly based on
the structures of SB-27701112 (Figure 1) and SB-41479613
*To whom correspondence should be addressed. Phone: þ39-045-
8218515. Fax: þ39-045-8118196. E-mail: fabrizio.micheli@aptuit.com.
Address: Aptuit Verona, Medicines Research Centre, Via Fleming 4,
37135 Verona, Italy.
a Abbreviations: hERG, human ether-a go-go related gene Kþ channel;
NCE, new chemical entity; PK, pharmacokinetic; P450, cytochrome P450;
hCli, human intrinsic clearance; F%, Bioavailability; B/B, brain/blood
ratio; Clb, blood clearance; Vd, distribution volume; clogD, calculated
logD; GPCR, G-protein coupled receptor; TM, trans membrane.
Results and Discussion
The synthesis of the final structures was performed through
the alkylation of the desired 3-[(3-chloropropyl)thio]-4-methyl-
5-aryl-1,2,4-triazole intermediate with the suitable amine,
r
2010 American Chemical Society
Published on Web 09/14/2010
pubs.acs.org/jmc

7130 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 19
Micheli et al.
Figure 1. Structures of the previously reported GSK selective DA D3 receptor antagonists.
Figure 2. The original pharmacophore model derived from SB-
277011 with the compound fitted. Red sphere, positive ionizable;
cyan spheres, hydrophobic; green spheres, hydrogen bond acceptor;
orange spheres, aromatic ring region.
similarly to previously reported7 reactions (a detailed syn-
thetic scheme is available in the Experimental Section). The
biological screening cascade for the progression of the new
compounds is detailed elsewhere.7 All the compounds were
assayed for their agonist and antagonist properties using a
functional GTPγS assay expressing the human DA D3 recep-
tor, the human DA D2 receptor, and the human ether-a-go-go
Kþ channel (hERG), a potential cardiovascular liability
target (using the dofetilide binding assay). The results of this
exploration are reported in Table 1.
Figure 3. (A) The new pharmacophore model with some of the
structures reported in Figure 1 fitted. Red sphere, positive ionizable;
cyan spheres, hydrophobic; green spheres, hydrogen bond acceptor;
orange spheres, aromatic ring region. (B) The new pharmacophore
model with the [3.1.0] system fitted.
This was probably due to the low lipophilicity of these
systems, similarly to some previously explored series.7 The
introduction of a 4-trifluoromethyl moiety on the phenyl
group (11, 12) achieved a more suitable ClogD profile with
good potency and selectivity. Specifically, the 1-phenyl-3-
azabicyclo[4.1.0]heptane 11 had higher DA D3 receptor affinity
compared to the regioisomeric 6-phenyl derivative 12, leading
When the racemic unsubstituted phenyl scaffolds were used
(9, 10), only poor activity was detected at the DA D3 receptor.

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Journal of Medicinal Chemistry, 2010, Vol. 53, No. 19 7131
Figure 4. (A) A series of structures which may represent potential alternative to the azabicyle[3.1.0]hexane system. (B) The fitting in the
pharmacophore model (only the positive ionizable and aromatic region are reported) of structure 6 (left panel, one enantiomer colored in
green), structure 7 (middle panel, one enantiomer colored in gold), and structure 27 (right panel, two enantiomers colored in green and gold)
with respect to the azabicyclo[3.1.0]hexane 1 (1S,5R enantiomer colored in red).
to a 60-fold selectivity vs the DA D2 receptor. When the 3
positions of the phenyl group were explored, the 6-phenyl-3-
azabicyclo[4.1.0]heptane 14 became now more potent and
selective at the DA D3 receptor compared to 13; unfortu-
nately, the activity of 14 at the hERG channel was also
relatively high and the compound was not progressed. The
increased bulkiness of the bicyclic ring moving to the 1-phenyl-
4-azabicyclo[5.1.0]octane system was not detrimental to the
DA D3 affinity (15-18), but the selectivity at the DA D2
receptor had to be fine-tuned. The slightly higher lipophilicity
of derivatives (15-17) with respect to 1 was probably the
cause of the increased affinity at the D2 receptor. The careful
design of the substituents used to decorate the right-hand-side
of this new template proved that this scaffold was worth
further investment. For example, the introduction of the
pyridazine moiety (18) achieved the same ClogD as derivative
1 and led to a molecule endowed with a 100-fold selectivity
over the D2 receptor. As previously described,7 each promis-
ing compound was profiled along the screening cascade to
ensure appropriate PK and developability characteristics.
When tested in the CYPEX bactosome P450 inhibition test
and in the rat and human in vitro clearance (Cli) in liver
microsomes, 18 showed a good profile: the IC50 values for all
major P450 isoforms tested (CYP1A2, CYP2C9, CYP2C19,
CYP2D6, and CYP3A4) were greater than 6 μM, and Cli
values both in human and rat were moderately low (0.8 and
0.5 mL/min/g of protein, respectively).
specific range of ClogD (between 2 and 4) was shown as
optimal for maximizing the DA D3 affinity. The results of the
final compounds (21-24) are reported in Table 2. Despite the
presence of a secondary amine, micromolar affinity was
achieved at the DA D3 receptor using amine 19. Taking into
consideration, however, the nonsubstituted nature of the
phenyl group and the relatively high metabolic fate of deri-
vative 21 (Cli = 2.6 and 5.4 mL/min/g of protein in human
and rat, respectively), the research focused primarily on the
4-trifluoromethyl regioisomer 20. Considering the presence of
multiple stereocenters, the strategy was to proceed with a
chiral separation of the four diastereoisomers; only three of
the latter (22-24) showed appropriate purity characteristics
for in vitro testing. Derivative 24, one of the two enantiomers
with a relative trans configuration between the secondary
amine and the phenyl group, showed a low micromolar
potency at the DA D3 receptor and a 100-fold selectivity vs
D2 target. IC50 values for all P450 isoforms tested were greater
than 4 μM and Cli values both in human and in rat were low
(<0.5 mL/min/g of protein for both targets). Accordingly,
this area was further developed and a fluorine atom was
introduced to slightly increase the ClogD value. The effect
of this substitution on the two reported trans derivatives (25
and 26) was greater on the less active enantiomer 26 at the DA
D3 receptor, leading to a more balanced profile. In contrast,
compound 25 did not show any major improvement in desired
affinity.
Another approach aimed at maintaining a bicyclic system
in the triazole scaffolds was the application of phenylbicyclo-
[3.1.0]hexane amines as the source of basic moiety in the
template. For this reason, the 1-phenylbicyclo[3.1.0]hexan-3-
amine (19, Figure 4A) and the 5-phenylbicyclo[3.1.0]hexan-2-
amine (20, Figure 4A) were selected despite a relatively
low ClogD. Actually, for previously described templates,7 a
Another innovative template was then hypothesized to sit
into the hydrophobic pocket close to the Asp110 region in the
DA D3 receptor.15 From the docking studies performed in
the receptor model and previously reported,9-11 this region
appeared relatively large because it was able to accommodate
bulky substituents like the amine portion of the BAZ systems
of derivatives 3, 4, 5. Accordingly, a series of spiro derivatives

7132 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 19
Micheli et al.
Table 1. Functional Activity at the Human DA D3 Receptor and Selectivity for Derivatives 9-18a
a fpKi = functional pKi obtained from the GTPγS functional assay. SEM for D3 GTPγS, and HERG data sets is (0.1 and for the D2L GTPγS data is
(0.2. * All the compounds were tested as racemates. # ACD logD 7.4. Ver 11.
were designed and one of these scaffolds (27) is reported in
Figure 4A. As it can be seen in the right panel of Figure 4B,
both the enantiomers of this structure (the green and gold
traces) fit well into the pharmacophore model when compared
to the azabicyclo[3.1.0]hexane. From a theoretical standpoint,
one of the two enantiomers (green) also seems to fit better in

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Journal of Medicinal Chemistry, 2010, Vol. 53, No. 19 7133
Table 2. Functional Activity at the Human DA D3 Receptor and Selectivity for 4 Derivatives 21-26a
a fpKi = functional pKi obtained from the GTPγS functional assay. SEM for D3 GTPγS, and HERG data sets is (0.1; SEM for the D2L GTPγS data
is (0.2. # ACD logD 7.4. Ver 11. * All the compounds were tested as racemates, unless specified (s.e. = single enantiomer). Relative stereochemistry is
shown. Figures (1 to 3 for compounds 22-24, and 1 to 2 for derivatives 25-26) are added to identify the different single enantiomers.
terms of overlap of the van der Waal’s volumes with the red
structure; a series of derivatives were prepared and the
biological results are reported in Table 3. The first part of
the exploration was performed using a 3,4-dihydro-2H-spiro-
[naphthalene-1,30-pyrrolidine] system. Despite a relatively
high ClogD, derivatives 28 and 29 were about 10-fold less
potent at the DA D3 receptor compared to1; the affinity atthe
DA D2 receptor was similarly reduced while the hERG
component remained unchanged. The reduction in lipophili-
city caused by the introduction of a methoxy group further
reduced the affinity at the desired target independent of its
position on the aromatic ring (30-32), and this caused a
decrease in the selectivity vs the DA D2 receptor because the
affinity at this target remained unchanged. The removal of the
methoxy group and the introduction of the oxygen in the six-
membered ring (33) had a positive impact on the reduction of
the D2 affinity. Improvement of desired activity at the D3
receptor was obtained with the smaller 2,3-dihydrospiro-
[indene-1,30-pyrrolidine] template (34-36). The positioning
ofthe bromineonthe aromatic ring seemedtoslightly increase
the affinity at the primary target, but unfortunately this also
went in the same direction for the secondary targets, thus
limiting the selectivity of the scaffold to about 30-fold. The use
of chlorine/fluorine together with a different heteroaromatic
group in right-hand-side of the scaffold (37-40) did not
modify the overall trend of this series. One may hypothesize
that the steric bulk of these structures is relatively well
tolerated by the DA D3 receptor in terms of affinity, but it
drastically changes the selectivity profile of this specific series,
potentially distorting other key interactions within the DA
receptors.
examples of this modification; more specifically, only the
endo derivatives results are reported based on purity criteria.
Derivative 41 showed nanomolar affinity at the DA D3
receptor and a good in vitro PK profile was good despite
the lipophilic nature of the t-Bu moiety on the aromatic ring.
The IC50 values for all major P450 isoforms tested were
greater than 5 μM and Cli values in humans were moderate
(1.9 mL/min/g of protein); Cli values in rats were however
high (7.9 mL/min/g of protein). Replacement with trifluoro-
methyl substituents (42) was performed to assess if Cli values
were associated with the nature of the t-Bu group. In this
derivative, the IC50 values for all P450 isoforms tested were
greater than 10 μM and Cli values both in human and in rat
were moderately low (0.9 and <0.5 mL/min/g of protein,
respectively). However, unexpected results were observed
around the affinity profile: while a slight decrease in the DA
D3 affinity was expected, there was no similar decrease in DA
D2 affinity but a significant increase in the hERG affinity. It
was postulated, therefore, that the decreased bulkiness of the
CF3- group allowed a different positioning of the phenyl
group in the hERG channel, while the former substituent
was bulky enough to prevent such interaction. To confirm this
working hypothesis, docking experiments in the hERG chan-
nel model were performed in agreement with previously
reported work.7 A pictorial representation of the results is
shown in Figure 5. In agreement with this model, the switch of
the CF3- group from the para to the meta position should
disfavor such interactions. This was demonstrated by com-
pound 43 with a 5-fold decrease in the hERG affinity.
Unfortunately, in these specific derivatives, the decrease in
hERG affinity was paralleled by a decreased affinity at both
the D2 and the D3 receptors. To regain DA D3 affinity in this
particular subseries, the introduction of a fluorine atom in
position ortho (44) fitted the purpose of changing both the
Finally, to conclude this part of the exploration, it was
decided to probe the region with a series of 3-phenyl-8-
azabicyclo[3.2.1]octanes. Table 4 reports some specific

7134 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 19
Micheli et al.
Table 3. Functional Activity at the Human DA D3 Receptor and Selectivity for 5-Oxazolyl Derivatives 28-40a
a fpKi = functional pKi obtained from the GTPγS functional assay. SEM for D3 GTPγS, and HERG data sets is (0.1; SEM for the D2L GTPγS data
is (0.2. # ACD logD 7.4. Ver 11. * All the compounds were tested as racemates.
stereoelectronic nature of the aromatic ring and its position
with respect to the tropane system in terms of dihedral angle,
leading to a compound with good affinity at the D3 receptor
and almost 100-fold selectivity over D2. The tropane system,
therefore, demonstrated an initial tractability as lead series
and further exploration will be performed in due course.

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Journal of Medicinal Chemistry, 2010, Vol. 53, No. 19 7135
Table 4. Functional Activity at the Human DA D3 Receptor and Selectivity for Derivatives 41-44a
a fpKi = functional pKi obtained from the GTPγS functional assay. SEM for D3 GTPγS, and HERG data sets is (0.1; SEM for the D2L GTPγS data
is (0.2. # ACD logD 7.4. Ver 11. * The relative stereochemistry represents the endo isomer.
Figure 5. Interactions of compound 42 in the hERG channel models. The backbone ribbon of the pore domain is included but that of the S5
and S6 helices has been removed for clarity. For details about the modeling techniques, please refer to ref 7.
Conclusions
Experimental Section
Biological Test Methods. In Vitro Studies. [35S] GTPγS Func-
tional Binding Assay in Cell Membranes Expressing hD3 Recep-
tors. In vitro functional studies were performed according to the
following [35S]-GTPγS protocol. Cells used in the study are
Chinese hamster ovary (CHO) cells.
Cell membranes were prepared as follows. Cell pellets were
resuspended in 10 volumes of 50 mM HEPES, 1 mM EDTA pH
7.4, using KOH. On the day following, the proteases were
added to the buffer just prior to giving the homogenization
buffer.
Starting from the potent and selective DA D3 receptor
antagonists previously reported (1-5), the present work
focused on a detailed exploration of the amine moiety of these
templates. Rational design and computational tools helped to
drive the selection of a number of compounds endowed with
high in vitro affinity and selectivity at the DA D3 receptor.
Furthermore, a better understanding of the region of the
receptor around Asp 110 was generated through these specific
compounds.

7136 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 19
Micheli et al.
10-6 M Leupeptin (Sigma L2884) - 5000 ꢀ stock = 5 mg/mL
Table 5
in buffer
25μg/mL bacitracin (Sigma B0125) - 1000 ꢀ stock = 25 mg/mL
analytical column
mobile phase
Zorbax SB-C18, 4.6 mm ꢀ 50 mm (1.8 μ)
amm acet, 5 mM þ 0.1% formic acid/acetonitrile
in buffer
þ 0.1% formic acid
1 mM PMSF - 1000 ꢀ stock = 17 mg/mL in 100% ethanol
2 ꢀ 10-6 M Pepstain A - 1000 ꢀ stock = 2 mM in 100%
DMSO
gradient
flow rate
detection
MS
97/3 f 36/64 v/v in 3.5 min f 10/90 in 3.5 min
2.0 mL/min
DAD, 210-350 nm
ESþ
The cells were homogenized by 2 ꢀ 15 s bursts in a 1 L glass
Waring blender in a class two biohazard cabinet. The resulting
suspension was spun at 500g for 20 min (Beckman T21 centri-
fuge: 1550 rpm). The supernatant was withdrawn with a 25 mL
pipet, aliquotted into prechilled centrifuge tubes, and spun at
48000g to pellet membrane fragments (Beckman T1270: 23000
rpm for 30 min). The final 48000g pellet was resuspended in
homogenization buffer, (4ꢀ the volume of the original cell
pellet). The 48000g pellet was resuspended by vortexing for 5 s
and homogenized in a dounce homogenizer 10-15 stokes. The
prep was distributed into appropriate sized aliquots (200-1000
μL) in polypropylene tubes and stored at -800 ꢀC. Protein
content in the membrane preparations was evaluated with the
Bradford protein assay.
The final top concentration of test drug was 3 μM in the assay,
and 11 points serial dilution curves 1:4 in 100% DMSO were
carried out using a Biomek FX. The test drug at 1% total assay
volume (TAV) was added to a solid, white, 384 well assay plate.
fifty percent TAV of precoupled (for 90 min at 4 ꢀC) membranes,
5 μg/well, and wheatgerm agglutinin polystyrene scintillation
proximity assay beads (RPNQ0260, Amersham), 0.25 mg/well,
in 20 mM HEPES pH 7.4, 100 mM NaCl, 10 mM MgCl2, 60 μg/mL
saponin, and 30 μM GDP was added. The third addition was a
20% TAV addition of either buffer, (agonist format) or EC80
final assay concentration of agonist, Quinelorane, prepared in
assay buffer (antagonist format). The assay was started by the
addition of 29% TAV of GTPγ[35S] 0.38 nM final
(37 MBq/mL, 1160 Ci/mmol, Amersham). After all additions ,
assay plates were spun down for 1 min at 1000 rpm. Assay plates
were counted on a Viewlux, 613/55 filter, for 5 min, between
2 and 6 h after the final addition.
each concentration of compound and converted to a percentage
of the mean control rate using Magellan (Tecan software). The
inhibition (IC50) of each compound was determined from the
slope of the plot using Grafit v5 (Erithacus software, UK).
Miconazole was added as a positive control to each plate. CYP450
isoform substrates used were ethoxyresorufin (ER; 1A2; 0.5 μM),
7-methoxy-4-triflouromethylcoumarin-3-acetic acid (FCA; 2C9;
50 μM), 3-butyryl-7-methoxycoumarin (BMC; 2C19; 10 μM),
4-methylaminomethyl-7-methoxycoumarin (MMC; 2D6; 10 μM),
diethoxyflourescein (DEF; 3A4; 1 μM), and 7-benzyloxyquinoline
(7-BQ; 3A4; 25 μM). The test was performed in three replicates.
Intrinsic Clearance (Cli) Assay. Intrinsic clearance (CLi)
values were determined in rat and human liver microsomes.
Test compounds (0.5 μM) were incubated at 37 ꢀC for 30 min in
50 mM potassium phosphate buffer (pH 7.4) containing 0.5 mg
microsomal protein/mL. The reaction was started by addition of
cofactor (NADPH; 8 mg/mL). The final concentration of
solvent was 1% of the final volume. At 0, 3, 6, 9, 15, and
30 min an aliquot (50 μL) was taken, quenched with acetonitrile
containing an appropriate internal standard, and analyzed by
HPLC-MS/MS. The intrinsic clearance (CLi) was determined
from the first-order elimination constant by nonlinear regres-
sion using Grafit v5 (Erithacus software, UK), corrected for
the volume of the incubation, and assuming 52.5 mg micro-
somal protein/g liver for all species. Values for CLi were
expressed as mL/min/g liver. The lower limit of quantification
of clearance was determined to be when <15% of the com-
pound had been metabolized by 30 min and this corresponded
to a CLi value of 0.5 mL/min/g liver. The upper limit was
50 mL/min/g liver.
Chemical Procedures. General. Experimental. NMR spectra
were obtained on Varian INOVA spectrometers (300, 400, and
500 MHz). Chemical shifts are expressed in δ (ppm) units, and
peak multiplicity are expressed as follows: singlet (s), doublet (d),
doublet of doublets (dd), triplet (t), multiplet (m), broad singlet
(br s), broad multiplet (br m). All mass spectrometric measure-
ments were performed using a Micromass Platform LCZ (Waters,
Manchester, UK) mass spectrometer operated in positive electro-
spray ionization mode. When LC/MS detection was performed,
analytical conditions were used as reported in Table 5.
General Synthetic Procedures. Appropriate primary or secon-
dary amines (commercially available or prepared in analogy
to the procedures described in refs 16-18) were reacted with
appropriately decorated 3-[(3-chloropropyl)thio]-4-methyl-4H-
1,2,4-triazoles (47) prepared by the corresponding aryl acids (45)
in agreement with literature procedures.7-11 The compounds
were suspended/dissolved in dry acetonitrile or DMF reacted in
the presence of potassium carbonate according to the reaction
Scheme 1 below. Crudes were evaporated and purified by column
chromatography. The three compounds reported as single enan-
tiomer (23, 25, 26) were obtained after preparative chromatogra-
phy on chiral columns and their enantiomeric purity always
verified on analytical column. The enatiomeric excess has been
measured by means of SFC analytical techniques. Typical condi-
tions arederived from Chiralpak AD-H column (25cm ꢀ 0.46 cm)
with ethanol (þ0.1% isopropylamine) 15% as modifier, flow rate
2.5 mL/min, P = 180 bar at 35 ꢀC with detection at 220 nm.
The purity of the compounds reported in the manuscript was
established through HPLC-MS methodology. All the com-
pounds reported in the manuscript have a purity >95%.
The effect of the test drug over the basal generates EC50 value
by an iterative least-squares curve fitting program, expressed in
the table as pEC50 (i.e., -log EC50). The ratio between the
maximal effect of the test drug and the maximal effect of full
agonist, Quinelorane, generates the intrinsic activity (IA) value
(i.e., IA = 1 full agonist, IA < 1 partial agonist). fpKi values of
test drug were calculated from the IC50 generated by “antagonist
format” experiment, using Cheng and Prusoff equation: fKi =
IC50/1 þ ([A]/EC50) where: [A] is the concentration of the
agonist in the assay and EC50 is the agonist EC50 value obtained
in the same experiment. fpKi is defined as -log fKi.
hERG-3H Dofetilide Binding Assay. hERG activity was mea-
3
sured using H dofetilide binding in a scintillation proximity
assay (SPA) format. The activity was measured with a Perki-
nElmer Viewlux imager.
P450 CYPEX Assay. Inhibition (IC50) of human CYP1A2,
2C9, 2C19, 2D6, and 3A4 was determined using Cypex bacto-
somes expressing the major human P450s. A range of concen-
trations (0.1, 0.2, 0.4, 1, 2, 4, and 10 μM) of test compound were
prepared in methanol and preincubated at 37 ꢀC for 10 min in
50mM potassiumphosphatebuffer (pH 7.4) containingrecombi-
nant human CYP450 microsomal protein (0.1 mg/mL; Cypex
Limited, Dundee, UK) and probe-fluorescent substrate. The
final concentration of solvent was between 3 and 4.5% of the
final volume. Following preincubation, NADPH regenerating
system (7.8 mg of glucose 6-phosphate, 1.7 mg of NADP, and
6 units of glucose 6-phosphate dehydrogenase/mL of 2% (w/v)
NaHCO3; 25 μL) was added to each well to start the reaction.
Production of fluorescent metabolite was then measured over a
10 min time course using a Spectrafluor plus plate reader. The
rate of metabolite production (AFU/min) was determined at

Article
Journal of Medicinal Chemistry, 2010, Vol. 53, No. 19 7137
Scheme 1. General Synthetic Procedures for the Preparation of Compounds 5-105a
a (i) T3P in AcOEt; (ii) 4-methyl-3-thiosemicarbazide; (iii) NaOH; (iv) K2CO3/acetone; (v) K2CO3/DMF or CH3CN.
3-(3-{[4-Methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-
3-yl]thio}propyl)-1-phenyl-3-azabicyclo[4.1.0]heptane Hydro-
chloride (9). 1H NMR (DMSO-d6): δ 9.93 (bs,1 H), 8.54 (m,
1 H), 7.43 (d, 2 H), 7.31 (m, 2 H), 7.22 (m, 1 H), 3.65 (m, 1 H),
3.38 (m, 8 H), 2.36 (m, 3 H), 2.14 (m, 2 H), 1.49 (m, 5 H). MS (m/z):
447 [MH]þ.
2 H), 7.20-7.10 (m, 3 H), 4.07-3.87 (m, 1 H), 3.71-3.63 (s, 3 H),
3.32-3.20 (t, 2 H), 3.09-2.90 (m, 2 H), 2.74-2.61(m,1H),2.61-2.50
(m, 1 H), 2.39-2.32 (s, 3 H), 2.15-2.07 (m, 1 H), 2.10-1.94 (m, 2 H),
1.83-1.62 (m, 2 H), 1.27-1.18 (m, 1 H), 1.10-1.01 (m, 1 H).
(3-{[4-Methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-3-yl]-
thio}propyl){(1S,2R,5S)-5-[4-(trifluoromethyl)phenyl]bicyclo-
[3.1.0]hex-2-yl}amine Hydrochloride (23). 13C NMR (DMSO-d6):
δ 152.0, 151.2, 150.2, 146.0, 137.0, 134.4, 126.1, 125.7 (q, J = 31.9
Hz), 124.9 (q, J = 3.9 Hz), 124.6 (q, J= 271.6 Hz), 59.2, 46.3, 31.5,
30.9, 30.7, 30.6, 29.7, 28.9, 27.3, 15.4, 12.2.
3-(3-{[4-Methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-
3-yl]thio}propyl)-6-phenyl-3-azabicyclo[4.1.0]heptane Hydro-
chloride (10). 1H NMR (MeOD): δ 8.38 (m, 1 H), 7.44 (d, 2 H),
7.32 (t, 2 H), 4.11 (dd, 1 H), 3.81 (m, 3 H), 3.37 (m, 5 H), 3.15 (dd, 1
H), 2.91 (m, 1 H), 2.57 (m, 1 H), 2.45 (m, 4 H), 2.27 (m, 2 H), 1.66
(m, 1 H), 1.29 (m, 1 H), 1.17 (m, 1 H). MS (m/z): 447 [MH]þ.
3-(3-{[4-Methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-
3-yl]thio}propyl)-1-[4-(trifluoromethyl)phenyl]-3-azabicyclo-
[4.1.0]heptane Hydrochloride (11). 1H NMR (DMSO-d6): δ 9.97
(bs,1 H), 8.57 (m, 1 H), 7.65 (m, 4 H), 3.89 (m, 1 H), 3.68 (m, 3 H),
3.24 (m, 6 H), 2.85 (m, 1 H), 2.54 (m, 1 H), 2.38 (s, 3 H), 2.19 (m,
2 H), 2.07 (m, 1 H), 1.38 (m, 3 H). MS (m/z): 478 [MH]þ.
3-(3-{[4-Methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-
3-yl]thio}propyl)-6-[4-(trifluoromethyl)phenyl]-3-azabicyclo-
[4.1.0]heptane Hydrochloride (12). 13C NMR (DMSO-d6): δ
152.1, 150.7, 149.9, 146.2, 137.2, 134.3, 128.9, 127.8, 127.1 (q,
J = 30.9 Hz), 125.3, 125.1 (q, J = 3.9 Hz), 124.3 (q, J = 271.6 Hz),
54.0, 50.2, 46.4, 31.7, 30.0, 27.2, 23.4, 22.8, 16.8, 15.3, 12.3.
3-(3-{[4-Methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-
3-yl]thio}propyl)-6-[3-(trifluoromethyl)phenyl]-3-azabicyclo-
[4.1.0]heptane Hydrochloride (14). 13C NMR (DMSO-d6): δ 152.1,
150.7, 146.6, 146.2, 137.1, 134.4, 132.5, 129.3, 129.1 (q, J = 31.9
Hz), 124.9, 124.1 (q, J = 272.6 Hz), 123.2, 54.0, 50.3, 46.4, 31.7,
30.0, 27.7, 23.4, 22.9, 16.4, 15.1, 12.3.
4-(3-{[5-(2,4-Dimethyl-1,3-oxazol-5-yl)-4-methyl-4H-1,2,4-triazol-
3-yl]thio}propyl)-1-[4-(trifluoromethyl)phenyl]-4-azabicyclo-
[5.1.0]octane Hydrochloride (16). 13C NMR (DMSO-d6): δ 161.4,
150.6, 149.6, 146.2, 138.1, 133.7, 128.4, 126.6 (q, J = 30.9 Hz),
125.2 (q, J = 3.9 Hz), 124.4 (q, J = 271.6 Hz), 55.7, 55.6, 53.3,
31.8, 31.0, 30.2, 27.2, 26.9, 25.8, 23.8, 23.2, 13.6, 12.3.
4-(3-{[5-(2,4-Dimethyl-1,3-thiazol-5-yl)-4-methyl-4H-1,2,4-triazol-
3-yl]thio}propyl)-1-[4-(trifluoromethyl)phenyl]-4-azabicyclo[5.1.0]-
octane Hydrochloride (17). 13C NMR (DMSO-d6): δ 167.6, 153.6,
151.1, 149.5, 148.1, 128.3, 126.6 (q, J = 31.9 Hz), 125.2, 125.1 (q,
J = 3.9 Hz), 124.0 (q, J = 271.8 Hz), 55.7, 55.6, 53.3, 31.6, 30.9,
30.0, 27.1, 26.9, 25.8, 23.9, 23.2, 18.8, 16.1.
{5-[2-Fluoro-4-(trifluoromethyl)phenyl]bicyclo[3.1.0]hex-2-yl}-
(3-{[4-methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-3-yl]-
thio}propyl)amine Hydrochloride (25). 13C NMR (DMSO-d6): δ
161.2 (d, J = 247.4 Hz), 152.1, 150.8, 146.2, 137.1, 134.5 (d, J =
13.5 Hz), 134.3, 131.8 (d, J = 3.9 Hz), 129.1, 123.4 (q, J = 274.5
Hz), 121.3, 112.9 (dq, J = 25.1 Hz, 3.9 Hz), 59.1, 44.5, 31.7, 30.8,
29.8, 28.6, 25.9, 24.0, 23.8, 12.2, 12.0.
5-[2-Fluoro-4-(trifluoromethyl)phenyl]bicyclo[3.1.0]hex-2-yl}-
(3-{[4-methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-3-yl]-
thio}propyl)amine Hydrochloride (26). 13C NMR (DMSO-d6): δ
161.2 (d, J = 247.4 Hz), 152.1, 150.8, 146.2, 137.1, 134.5 (d, J =
13.5 Hz), 134.3, 131.8 (d, J = 3.9 Hz), 129.1, 123.4 (q, J = 274.5
Hz), 121.3, 112.9 (dq, J = 25.1 Hz, 3.9 Hz), 59.1, 44.5, 31.7, 30.8,
29.8, 28.6, 25.9, 24.0, 23.8, 12.2, 12.0.
6-Bromo-10-(3-{[4-methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-
1,2,4-triazol-3-yl]thio}propyl)-3,4-dihydro-2H-spiro[naphthalene-
1,30-pyrrolidine] Hydrochloride (28). 1H NMR (DMSO-d6) δ ppm
10.44 (br s, 1 H), 8.55-8.58 (m, 1 H), 7.56 (d, 1 H), 7.34-7.43 (m,
1 H), 7.29-7.32 (m, 1 H), 3.70-3.82 (m, 2 H), 3.65-3.71 (m, 3 H),
3.22-3.48 (m, 5 H), 3.10-3.21 (m, 1 H), 2.67-2.76 (m, 2 H),
2.32-2.41 (m, 4 H), 1.78-2.27 (m, 7 H), 1.64-1.76 (m, 2 H).
7-Bromo-10-(3-{[4-methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-
1,2,4-triazol-3-yl]thio}propyl)-3,4-dihydro-2H-spiro[naphthalene-
1,30-pyrrolidine] Hydrochloride (29). 1H NMR (DMSO-d6) δ ppm
10.48(brs, 1H), 8.55-8.58 (m, 1 H), 7.80-7.89(m, 1H), 7.28-7.36
(m, 1 H), 7.00-7.08 (m, 1 H), 3.70-3.87 (m, 2 H), 3.67-3.70 (m,
3 H), 3.34-3.41 (m, 2 H), 3.25-3.32 (m, 2 H), 3.11-3.26 (m, 2 H),
2.67-2.68 (m, 2 H), 2.35-2.38 (m, 3 H), 2.34-2.44 (m, 1 H),
2.02-2.29 (m, 3 H), 1.63-2.03 (m, 4 H).
10-(3-{[4-Methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-
3-yl]thio}propyl)-6-(methyloxy)-3,4-dihydro-2H-spiro[naphthalene-
1,30-pyrrolidine] Hydrochloride (30). 1H NMR (DMSO-d6) δ ppm
10.34 (br s, 1 H), 8.49-8.60 (m, 1 H), 7.48 (d, 1 H), 6.72-6.84 (m,
1 H), 6.54-6.65 (m, 1 H), 3.63-3.79 (m, 8 H), 3.05-3.50 (m, 6 H),
2.61-2.77 (m, 2 H), 2.32-2.40 (m, 3 H), 2.25-2.44 (m, 1 H),
2.08-2.22 (m, 2 H), 1.55-2.07 (m, 5 H).
4-(3-{[4-Methyl-5-(4-pyridazinyl)-4H-1,2,4-triazol-3-yl]thio}-
propyl)-1-[4-(trifluoromethyl)phenyl]-4-azabicyclo[5.1.0]octane
(18). 1H NMR (DMSO-d6): δ 9.65 (d, 1 H), 9.4 (d, 1 H), 7.90 (d,
1 H), 7.70 (d, 2 H), 7.42 (d, 2 H), 3.75 (s, 3 H), 3.45 (t, 2 H), 2.96 (m,
1 H), 2.77 (m, 1 H), 2.65 (t, 2 H), 2.54 (m, 2 H), 2.35 (m, 2 H), 2.19
(m, 2 H), 1.8 (m, 1 H), 1.65 (s, 3 H), 1.40 (m,1 H), 1.09 (d, 1 H), 0.95
(m, 1 H). MS (m/z): 489.2 [MH]þ.
10-(3-{[4-Methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-
3-yl]thio}propyl)-5-(methyloxy)-3,4-dihydro-2H-spiro[naphthalene-
1,30-pyrrolidine] Hydrochloride (31). 1H NMR (DMSO-d6) δ ppm
10.54 (br s, 1 H), 8.52-8.61 (m, 1 H), 7.11-7.29 (m, 2 H), 6.75-6.85
(m, 1 H), 3.74-3.75 (m, 3 H), 3.71-3.81 (m, 2 H), 3.66-3.70 (m,
3 H), 3.34-3.49 (m, 3 H), 3.24-3.32 (m, 2 H), 3.11-3.22 (m, 1 H),
2.56-2.65 (m, 1 H), 2.43-2.54 (m, 1 H), 2.35-2.37 (m, 3 H),
2.32-2.41 (m, 1 H), 2.09-2.25 (m, 2 H), 1.92-2.09 (m, 1 H),
1.60-1.92 (m, 4 H).
13C NMR (DMSO-d6): δ 152.6, 151.8, 151.1, 149.5, 149.1, 128.3,
126.6 (q, J = 31.9 Hz), 125.7, 125.2 (q, J = 3.9 Hz), 124.5 (q, J =
271.6 Hz), 55.8, 55.6, 53.3, 32.1, 31.0, 29.9, 27.1, 27.0, 25.8, 24.0, 23.2.
(3-{[4-Methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-3-yl]-
thio}propyl)-1-phenylbicyclo[3.1.0]hexan-3-amine Hydrochloride
(21). 1H NMR (DMSO-d6): δ 8.60-8.51 (m, 1 H), 7.31-7.22 (m,

7138 Journal of Medicinal Chemistry, 2010, Vol. 53, No. 19
Micheli et al.
10-(3-{[4-Methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-
3-yl]thio}propyl)-7-(methyloxy)-3,4-dihydro-2H-spiro[naphthalene-
1,30-pyrrolidine] Hydrochloride (32). 1H NMR (DMSO-d6) δ ppm
10.12-11.03 (m, 1 H), 8.50-8.62 (m, 1 H), 7.04-7.28 (m, 1 H),
6.91-7.04 (m, 1 H), 6.66-6.82 (m, 1 H), 3.73-3.76 (m, 3 H), 3.69-
3.87 (m, 2 H), 3.66-3.70 (m, 3 H), 3.23-3.51 (m, 5 H), 3.10-3.24
(m, 1 H), 2.59-2.68 (m, 2 H), 2.36-2.47 (m, 1 H), 2.34-2.37 (m,
3 H), 1.62-2.23 (m, 7 H).
137.0, 134.4, 128.0, 126.3 (q, J = 31.9 Hz), 124.8 (q, J = 3.9 Hz),
124.3(q, J = 271.6 Hz), 57.1, 50.1, 38.2, 32.6, 31.6, 30.9, 28.6, 28.3,
12.2.
8-(3-{[4-Methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-
3-yl]thio}propyl)-3-[3-(trifluoromethyl)phenyl]-8-azabicyclo[3.2.1]-
octane (43). 13C NMR (DMSO-d6): δ 152.0, 151.4, 147.7, 146.0,
137.0, 134.4, 131.5, 129.0, 128.8 (q, J = 31.9 Hz), 124.4 (q, J =
272.6 Hz), 123.6 (q, J = 3.9 Hz), 122.3 (q, J = 3.9 Hz), 57.0, 50.2,
38.6, 32.5, 31.5, 30.9, 28.7, 28.5, 12.2.
3-[2-Fluoro-4-(trifluoromethyl)phenyl]-8-(3-{[4-methyl-5-(4-methyl-
1,3-oxazol-5-yl)-4H-1,2,4-triazol-3-yl]thio}propyl)-8-azabicyclo[3.2.1]-
octane (44). 13C NMR (DMSO-d6): δ 160.1 (d, J = 246.5 Hz),
152.0, 151.4, 146.0, 137.9 (d, J = 13.5 Hz), 137.0, 134.4, 130.2 (d,
J = 4.9 Hz), 128.2 (dq, J = 32.9 Hz, 8.7 Hz), 123.4 (q, J = 271.6
Hz), 121.2, 112.5 (dq, J = 27.1 Hz, 3.9 Hz), 56.7, 50.3, 37.9, 31.5,
31.0, 29.1, 28.7, 26.4, 12.2.
10-(3-{[4-Methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,4-triazol-
3-yl]thio}propyl)-2,3-dihydrospiro[chromene-4,30-pyrrolidine] Hydro-
chloride (33). 1H NMR (DMSO-d6) δ ppm 10.60 (br s, 1 H), 8.54-
8.59 (m, 1 H), 7.53-7.61 (m, 1 H), 7.09-7.17 (m, 1 H), 6.91-6.97
(m, 1 H), 6.73-6.79 (m, 1 H), 4.07-4.21 (m, 2 H), 3.73-3.85 (m, 2
H), 3.66-3.70 (m, 3 H), 3.26-3.31 (m, 2 H), 3.22-3.50 (m, 4 H),
2.39-2.47 (m, 1 H), 2.35-2.38 (m, 3 H), 1.93-2.28 (m, 5 H).
13C NMR (DMSO-d6): δ 153.5, 152.0, 151.3, 146.0, 137.0,
134.4, 130.9, 127.8, 126.9, 120.6, 116.1, 69.0, 63.6, 53.7, 53.6,
41.7, 40.6, 35.6, 31.5, 30.9, 28.1, 12.2.
Acknowledgment. We thank Dr. Stefano Fontana,
Dr. Chiara Savoia, Dr. Francesca Cardullo, Dr. Elettra Fazzolari,
and Silvia Tomelleri for the management of some of the com-
pounds reported in this manuscript. We also thank Dr. Daniele
Donati, Dr. Tino Rossi, and Dr. Jim Hagan for the fruitful
discussions during the life of the programme.
5-Bromo-10-(3-{[3-(4-methyl-1,3-oxazol-5-yl)-1H-1,2,4-triazol-
5-yl]thio}propyl)-2,3-dihydrospiro[indene-1,30-pyrrolidine] Hydro-
chloride (34). 1H NMR (DMSO-d6) δ ppm 1.82-2.39 (m, 6 H),
2.29-2.35 (m, 3 H), 2.76-2.92 (m, 2 H), 3.04-3.49 (m, 6 H),
3.57-3.80 (m, 2 H), 3.64 (s, 3 H), 7.30-7.50 (m, 3 H), 8.44-8.58
(m, 1 H), 10.70 (br s, 1 H).
4-Bromo-10-(3-{[4-methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,
4-triazol-3-yl]thio}propyl)-2,3-dihydrospiro[indene-1,30-pyrrolidine]
Hydrochloride (35). 13C NMR (DMSO-d6): δ 152.9, 152.0, 151.3,
146.0, 142.9, 137.0, 134.4, 129.2, 129.0, 121.9, 118.9, 66.5, 54.7,
53.7, 53.6, 39.4, 39.0, 31.6, 31.5, 30.8, 28.2, 12.3.
6-Bromo-10-(3-{[4-methyl-5-(4-methyl-1,3-oxazol-5-yl)-4H-1,2,
4-triazol-3-yl]thio}propyl)-2,3-dihydrospiro[indene-1,30-pyrrolidine]
Hydrochloride (36). 13C NMR (DMSO-d6): δ 153.6, 152.0, 151.3,
146.1, 142.2, 137.0, 134.4, 129.1, 126.2, 125.6, 119.3, 66.2, 53.7,
53.5, 53.4, 40.4, 38.5, 31.5, 30.9, 29.7, 28.2, 12.3.
6-Chloro-10-(3-{[5-(2,4-dimethyl-1,3-thiazol-5-yl)-4-methyl-4H-
1,2,4-triazol-3-yl]thio}propyl)-2,3-dihydrospiro[indene-1,30-pyrrolidine]
Hydrochloride (37). 13C NMR (DMSO-d6): δ 166.8, 153.2, 153.1,
151.2, 148.2, 141.7, 130.9, 126.3, 125.7, 122.6, 114.8, 66.2, 53.7, 53.5,
53.4, 40.5, 38.5, 31.2, 30.7, 29.6, 28.2, 18.8, 16.1.
5-Chloro-10-(3-{[5-(2,4-dimethyl-1,3-thiazol-5-yl)-4-methyl-4H-
1,2,4-triazol-3-yl]thio}propyl)-2,3-dihydrospiro[indene-1,30-pyrrolidine]
Hydrochloride (38). 13C NMR (DMSO-d6): δ 166.8, 153.2, 151.1,
148.2, 145.4, 143.9, 133.9, 126.5, 124.3, 124.1, 114.8, 62.8, 53.7,
53.6, 52.9, 40.3, 38.4, 31.2, 30.5, 30.0, 27.8, 18.8, 16.1.
10-(3-{[5-(2,4-Dimethyl-1,3-thiazol-5-yl)-4-methyl-4H-1,2,4-triazol-
3-yl]thio}propyl)-5-fluoro-2,3-dihydrospiro[indene-1,30-pyrrolidine]
Hydrochloride (39). 13C NMR (DMSO-d6): δ 166.8, 161.4 (d, J =
239.7 Hz), 153.2, 151.2, 148.2, 146.4, 145.3 (d, J = 8.7 Hz), 123.8
(d, J = 8.7 Hz), 114.8, 113.2 (d, J = 22.2 Hz), 110.9 (d, J = 21.3
Hz), 66.4, 53.8, 53.6, 52.6, 40.9, 38.8, 31.2, 30.7, 30.1, 28.3, 18.8,
16.1.
10-(3-{[5-(2,4-Dimethyl-1,3-thiazol-5-yl)-4-methyl-4H-1,2,4-triazol-
3-yl]thio}propyl)-6-fluoro-2,3-dihydrospiro[indene-1,30-pyrrolidine]
Hydrochloride (40). 13C NMR (DMSO-d6): δ 166.8, 161.7 (d, J =
240.7 Hz), 153.2, 153.1 (d, J = 7.7 Hz), 151.2, 148.2, 138.4, 125.3
(d, J = 8.7 Hz), 114.8, 113.1 (d, J = 22.2 Hz), 109.5 (d, J = 22.2
Hz), 66.1, 53.8, 53.6, 53.5, 40.9, 38.5, 31.2, 30.7, 29.4, 28.2, 18.8,
16.1.
Supporting Information Available: Computational chemistry
details and additional pharmacophore fitting with the new
model. This material is available free of charge via the Internet
at http://pubs.acs.org.
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[3.2.1]octane Hydrochloride (41). 1H NMR (MeOD): δ ppm 8.43
(s, 1 H) 7.42 (d, 2 H) 7.37 (d, 2 H) 4.04 (m, 2 H) 3.77 (s, 3 H) 3,23
(t, 2 H) 3,3 (br. s, 1 H) 3.18 (t, 2 H) 2.62 (m, 4 H) 2.42 (s, 3 H), 2.24
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(9) Micheli, F.; Bonanomi, G.; Blaney, F. E.; Braggio, S.; Capelli,
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