Benzoazepine derivative as potent antagonists of the glycine binding site associated to the NMDA receptor

Article abstract of DOI:10.1016/S0014-827X(03)00166-6

A series of benzoazepine derivatives, bearing suitable substituents at the C-3 position, was designed and evaluated by superimposition with the pharmacophore model of the glycine binding site. To fully explore the SAR of this class of compounds and to allow the preparation of new different compounds at the C-3 position, appropriate synthetic routes were set up. The benzoazepines were evaluated in terms of in vitro affinity using [ ³H]glycine binding assay and in vivo potency by inhibition of convulsions induced by N-methyl-D-aspartate (NMDA) in mice. This further analysis confirmed the preliminary results previously reported and that compound 27 is the most promising compound (Ki=32 nM, ED₅₀=0.09 mg/kg, i.v.) in this series. Significant neuroprotective effect was observed after both pre- and post-ischaemia administration in the MCAo model. In particular, after post-ischaemia administration, it was found to be still effective when the administration was delayed up to 6 h after occlusion of the middle cerebral artery.

Full text of DOI:10.1016/S0014-827X(03)00166-6

Il Farmaco 58 (2003) 723Á738
/
www.elsevier.com/locate/farmac
Benzoazepine derivative as potent antagonists of the glycine binding
site associated to the NMDA receptor
Romano Di Fabio *, Fabrizio Micheli, Davide Baraldi, Barbara Bertani, Nadia Conti,
Giovanna Dal Forno, Aldo Feriani, Daniele Donati, Carla Marchioro,
Tommaso Messeri, Andrea Missio, Alessandra Pasquarello, Giorgio Pentassuglia,
Domenica A. Pizzi, Stefano Provera, Anna M. Quaglia, Fabio M. Sabbatini
Medicines Research Centre, GlaxoSmithKline S.p.A, Via Fleming 4, 37135 Verona, Italy
Received 4 April 2003; accepted 26 May 2003
Abstract
A series of benzoazepine derivatives, bearing suitable substituents at the C-3 position, was designed and evaluated by
superimposition with the pharmacophore model of the glycine binding site. To fully explore the SAR of this class of compounds and
to allow the preparation of new different compounds at the C-3 position, appropriate synthetic routes were set up. The
benzoazepines were evaluated in terms of in vitro affinity using [3H]glycine binding assay and in vivo potency by inhibition of
convulsions induced by N-methyl-
D-aspartate (NMDA) in mice. This further analysis confirmed the preliminary results previously
reported and that compound 27 is the most promising compound (Kiꢀ
/
32 nM, ED50 0.09 mg/kg, i.v.) in this series. Significant
ꢀ
/
neuroprotective effect was observed after both pre- and post-ischaemia administration in the MCAo model. In particular, after post-
ischaemia administration, it was found to be still effective when the administration was delayed up to 6 h after occlusion of the
middle cerebral artery.
´
# 2003 Editions scientifiques et me´dicales Elsevier SAS. All rights reserved.
Keywords: NMDA receptor; Benzoazepine derivatives; Glycine
1. Introduction
identification of several classes of glycine antagonists,
and a selected number of these derivatives is shown in
Fig. 1.
In the last decade the modulation of the NMDA
receptor has been proven, in animal models of cerebral
ischaemia, to represent a valuable biological strategy to
identify effective neuroprotective agents. In particular,
antagonists acting at the non-competitive glycine bind-
ing site were found to counteract the excitotoxic cascade
triggered by the stroke onset. These compounds, having
been associated to a clean side-effects profile, might be
able to offer similar efficacy, but greater therapeutic
opportunities with respect to both competitive NMDA
To a better understanding of the glycinergic mechan-
ism, our research was focussed on the identification of
novel classes of glycine antagonists devoid of the more
classical indole scaffold [20] but with a comparable
pharmacological profile. In particular, a class of benzo-
[b]-azepine derivatives, substituted at the C-5 position
with the same a,b-unsaturated chain present in the
indole series, was designed (Fig. 2) [26]. The super-
imposition of this template with the pharmacophore
model of the glycine binding site (Fig. 3) suggested that
the presence of H-bond donor or a negatively charged R
group at the C-3 position could be instrumental to
maximise their affinity to the glycine binding site.
Following this working hypothesis, the SAR of this
class of C-3 substituted benzazepine derivatives was
antagonists and NMDA channel blockers [1Á
Considerable effort has then been devoted to find
potent and selective ligands [16Á26], resulting in the
/
15].
/
* Corresponding author.
E-mail address: rdf26781@gsk.com (R. Di Fabio).
´
0014-827X/03/$ - see front matter # 2003 Editions scientifiques et me´dicales Elsevier SAS. All rights reserved.
doi:10.1016/S0014-827X(03)00166-6

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R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á738
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Fig. 3. Superimposition of 27 (Green) with GV150526A (Red) within
the pharmacophore model of the glycine binding site. Common
features are represented by H-bond acceptor (green), H-bond donor
(purple), Hydrophobic (cyan) and Negative inonizable (blue) spheres.
Fig. 1. Structures of various glycine antagonists.
explored in detail adding new selected derivatives with
respect to those already published in a preliminary
report [26].
Compound 27 (Table 1) confirmed to be the most
promising derivative of this series and its pharmacolo-
gical characterization confirmed the neuroprotective
effect of this glycine antagonist.
quired chemical conditions for the final deprotective
step. Thus, for the preparation of the C-3 substituted
hydroxy derivative, 2-bromo-5-chloro aniline (1) was
reacted, according to Weinreb conditions, with the
substituted butyrolactone 2 to yield the amido inter-
mediate 3. Its primary alcoholic function was masked as
tert-butyldimethylsilyl (TBDMS) ether, and the result-
ing compound 4 was protected as PMB derivative 5
generating the anion with NaH in THF and quenching
the reaction adding PMB chloride. After deprotection of
the primary alcoholic function, compound 6 was
oxidized, under Swern conditions, to obtain the alde-
hyde 7, which was submitted to a thermal Wittig-type
olefination reaction to yield compound 8 [27]. Amida-
tion reaction, according to the Weinreb’s conditions
[28], yielded compound 9, which was submitted to the
Heck-type cyclization reaction, using Pd(PPh3)4 as
catalyst. The desired compound 10a together with the
undesired isomer 10b was formed in 85/15 ratio; the
latter was then easily removed by flash chromatography
[29]. Finally, removal of the protecting groups with
anisole in H2SO4/TFA at 80 8C yielded the target
compound 11.
2. Synthesis
To prepare the derivatives reported in Table 1,
different synthetic approaches were set up, depending
on the substituents in the C-3 position. As represented in
Scheme 1, the key step of the synthetic route was
represented by Heck-type cyclization reaction (step h)
in which the E stereochemistry of the exocyclic double
bond was controlled starting from the appropriate
stereochemistry of the double bond of the acrylate
intermediate. Moreover, to increase the efficiency of
this cyclization, it was necessary to shift the cisoid/
transoid equilibrium of the amide group towards the
transoid rotamer (Fig. 4). To achieve this purpose, the
p-methoxybenzyl (PMB) group was selected as an
appropriate protecting group considering also the re-
To prepare compounds 19a and 19b (Rꢀ
/
NHSO2CH3 and NHSO2CF3, respectively) the synthetic
route shown in Scheme 2 was followed. Alkylation of
the aniline 1 with PMBCl in DMF in the presence of
NaI at 80 8C gave compound 12, which was acylated
with N-benzyloxycarbonyl-allylglycyl chloride to obtain
compound 13. Then, the allylic double bond was
transformed into the aldehyde 14 through ozonolysis.
Sequential Wittig-type olefination reaction followed by
deprotection of the t-butyl ester and amidation reaction
Fig. 2. Benzo-[b]-azepine template.

R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á
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725
Table 1
Substitution at the C-3 position
Entry
R
Ki (nM) a
NMDA induced convulsions model in mice b
11 #
19a
19b
27 #
OH
1288
NHSO2CH3
NHSO2CF3
COOH
ꢀ
105
2692
32
/
0.07 c
(0.030Á0.230)
/
28a
CONHOH
CONH2
44
39
40%
30%
30%
28b #
28c #
28d
CONHPh
CON(CH3)2
CN
72
2239
339
234
20893
3
28e #
28f
CONHSO2Ph
COPh
35
GV150526
0.06 c
(0.005Á0.42)
/
a
Inhibition of binding of [3H]-glycine.
b
c
Percentage of inhibition of convulsions at 0.1 mg/kg, i.v.
ED50 (mg/kg).
Reported also in Ref. [26].
#
a
Scheme 1. Reagents and conditions: (a) Et2AlCl 1 M Hex, CH2Cl2; (b) TBDMSCl, imidazole, 4-(dimethylamino)pyridine, DMF; (c) NaH, NaI,
4(MeO)PhCH2Cl (PMBCl), DMF, 80 8C; (d) p-toluenesulfonic acid, MeOH; (e) DMSO, (COCl)2, TEA, CH2Cl2, ꢁ
/
78Á
/
ꢁ
/
20 8C; (f) Ph3
PÄCHCOOEt, toluene, 70 8C; (g) aniline, Et2AlCl 1 M Hex, toluene, 80 8C; (h) Pd(PPh3)4, CH3CN, TEA, reflux; (i) CF3COOH, anisole, H2SO4,
/

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R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á
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738
Fig. 4.
with aniline allowed the preparation of the key inter-
mediate 16. Heck-type cyclization reaction followed by
derivative 25 permitted shorter reaction times thus
avoiding the formation of the endo double bond isomer.
The final removal of the protecting groups in acid
medium gave the carboxyl derivative 27. This compound
removal of both NÃ
/
Cbz and NÃ/PMB protecting groups
under acid conditions yielded the amino derivative 18.
The latter was transformed into the sulfonamide deri-
vatives 19a and 19b by reaction with (CF3SO2)2O and
CH3SO2Cl, respectively.
was then smoothly transformed into derivatives 28aÁd
/
by simple activation of the carboxyl group and reaction
with hydroxylamine, secondary or tertiary amines. The
cyano derivative 28e was obtained by treatment of the
amido derivative 28b with trifluoroacetic anhydride and
pyridine in THF. The phenylsulfonylaminocarbonyl
derivative 28f, was prepared starting from the com-
pound 26. Thus, after deprotection of the t-butyl ester
with formic acid and activation of the acid function,
compound 29 was reacted with phenylsulfonylamine
sodium salt to give the compound 30; the latter was
deprotected in acid medium to yield the desired deriva-
tive 28f.
Finally, the synthesis of the C-3 benzoyl derivative is
reported in the Scheme 4. Treatment of the malonic
derivative 24 with a 1 M sodium bis(trimethylsilyl)amide
solution in THF followed by addition of benzoyl
chloride yielded the compound 31. Deprotection of the
The benzoazepine derivatives 28aÁf were synthesized
/
according to the synthetic sequence shown in Scheme 3.
Protection of the aniline derivative 20 with PMBCl
yielded the compound 21, which was reacted with
methyl malonyl chloride to give the intermediate 22.
Sequential hydrolysis of the methyl ester, activation of
the acid function and reaction with t-butanol yielded
intermediate 24 [30]. Taking advantage from the pre-
sence of the malonic moiety, treatment of the compound
24 with a 1 M sodium bis(trimethylsilyl)amide solution
in THF followed by addition of E-4-bromo-crotonani-
lide allowed to prepare the open intermediate 25 which
was submitted to the Heck-type cyclization reaction
yielding the compound 26. In this event, it is worth
underlining that the Heck-type reaction on the iodine
a
Scheme 2. Reagents and conditions: (a) NaI, 4(MeO)PhCH2Cl (PMBCl), DMF, 80 8C; (b) pyridine, CH2Cl2; (c) 1) ozone, ꢁ
/
78 8C, 2) PPh3;
(d) PH3 PÄ
/
CHCOOt-Bu, toluene, reflux; (e) HCOOH; (f) 1-hydroxybenzotriazole, dicyclohexylcarbodiimide, aniline, DMF; (g) Pd(PPh3)4, DMF,
TEA, 110 8C; (h) CF3COOH, anisole, H2SO4, 80 8C; (i) (CF3SO2)2O, TEA, THF, ꢁ
/78 8C; (j) CH3SO2Cl, TEA, THF, 0 8C.

R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á
/
738
727
a
Scheme 3. Reagents and conditions: (a) NaI, 4(MeO)PhCH2Cl (PMBCl), DMF, 80 8C; (b) ClCOCH2COOMe, pyridine, toluene, 0 8C; (c) LiOH,
THF, H2O; (d) 4-(dimethylamino)pyridine, 2-methyl-2-propanol, 1-[-3-(dimethylamino)propyl)]-3-ethylcarbodiimide HCl, CH2Cl2; (e) [(CH3)3Si]2N-
Na, BrCH2CHÄCHCONHPh, 0 8C; (f) Pd(PPh3)4, CH3CN, TEA, reflux; (g) CF3COOH, anisole, H2SO4, 80 8C; (h) 1-hydroxybenzotriazole, 1-[-3-
/
(dimethylamino)propyl)]-3-ethylcarbodiimide HCl, (CH3)3CSiONH2, TEA, CH3CN; (i) 1-hydroxybenzotriazole, 1-[-3-(dimethylamino)propyl)]-3-
ethylcarbodiimide HCl, (CH3)3SiNH2, CH3CN; (j) 1-hydroxybenzotriazole, 1-[-3-(dimethylamino)propyl)]-3-ethylcarbodiimide HCl, PhNH2; (m) 1-
hydroxybenzotriazole, 1-[-3-(dimethylamino)propyl)]-3-ethylcarbodiimide HCl, (CH3)2NH;(n) HCOOH;(o) carbonyldiimidazole, PhSO2NHNa,
DMF; (p) CF3COOH, anisole, H2SO4, 80 8C; (CF3CO)2O, pyridine, THF.
t-butyl ester with trifluoroacetic acid afforded the acid
derivative which easily decarboxylated in the reaction
medium to yield the compound 32. Sequential alkylation
of the compound 32 with E-4-bromo-crotonanilide,
Heck-type cyclization reaction and deprotection of the
PMB function yielded the desired compound 35.
3. Biology
The biological evaluation of the new chemical entities
(NCEs) was performed according to the following
screening cascade [20,31]: (a) binding assay to evaluate
the affinity for the glycine site/functional activity; (b)
a
Scheme 4. Reagents and conditions: (a) [(CH3)3Si]2NNa, PhCOCl, THF, ꢁ
/
78 8C to r.t.; (b) CF3COOH; (c) [(CH3)3Si]2NNa, BrCH2CHÄ
/
CHCONHPh, ꢁ
/
78 to 0 8C; (d) Pd(PPh3)4, DMF, TEA, 110 8C; (e) CF3COOH, anisole, H2SO4, 80 8C.

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R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á738
/
selectivity for the glutamate receptors (NMDA/AMPA/
KA); (c) in vivo anticonvulsant activity in the NMDA
induced convulsions model in CD-1 mice (i.v. and p.o.)
to assess preliminary pharmacological profile; (d) in
vivo evaluation of the neuroprotective activity in the
middle cerebral artery occlusion (MCAo) model in male
primary and secondary amides (Rꢀ
CONHPh, entry 28b and 28c, Kiꢀ39 and 72 nM,
respectively). Moreover, the corresponding tertiary
dimethylamide derivative [RꢀCON(CH3)2, entry 28d,
Kiꢀ2239] was significantly less active with respect to
both the amides 28b and 28c, suggesting that the
negatively charged carboxylate could be replaced by
an amide group able to act as H-bond donor; (d) a
significant decrease of affinity with respect to compound
27 was observed for alternative electron withdrawing
/
CONH2 and
/
/
/
SpragueÁDawley rats as described by Tamura.
/
As far as the NMDA-induced convulsions model was
concerned, to further increasing its throughput and
based on the known anticonvulsant activity of the
reference compound GV150526, all NCEs exhibiting
substituents able to act as H-bond acceptors (Rꢀ
/
suitable in vitro affinity (KiB/100 nM) were tested iv at
COPh, CN, entry 35 and 28e, Kiꢀ20893 and 339,
/
a single dose (0.1 mg/kg). Only compounds inhibiting
50% of convulsions, induced by the preemptive icv
administration of the glycine binding site agonist
NMDA, were fully characterized in terms of dose
response curve to assess the ED50. This model can be
considered a surrogate of cerebral ischaemia in the
animal that allow gathering rapid information on
pharmacological/brain penetration profile of the NCEs
in a very early phase of the screening cascade. Further,
the evaluation of the ED50 was assessed only on the
better compounds to rapidly obtain the selection the
best compounds to eventually progress into the low
throughput MCAo model in rats.
respectively), further strengthening the previous hypoth-
esis.
In summary, the presence at the position C-3 of a
carboxylic group, negatively charged at physiological
pH, (H-bond acceptor effect or coulombic interaction)
or, conversely, of a primary and secondary amide (H-
bond donor effect), seems to be crucial to maximize the
in vitro affinity to the glycine binding site. This opposite
electronic effect observed for the COOH and the
CONHR groups, was difficult to explain based on the
results available to date. However, it seems reasonable
to hypothesize that the binding of both substituents
could be mediated by H2O, responsible for a ‘bridging’
effect between the molecule and the receptor pocket.
In contrast to the indole-2-carboxylates analogues of
GV150526 [20], where the transformation of the car-
boxylic function into the amido function resulted in a
4. Results and discussion
The benzoazepine template [26], substituted at the C-5
position with the same a,b-unsaturated chain present in
the indole series, was fitted on the known pharmaco-
phore model of the glycine binding site built up in house
[20]. As shown in Fig. 3, this template was superimposed
to this model satisfying the observed pharmacophore
arrangement. In particular, as far as the key carboxyl
group present at the C-2 position of GV150526 was
concerned, we argued that either the synergistic action
of the C-2 carbonyl group with a suitable C-3 H-bond
donor or a negatively charged substituent (R) could
mimic the acid function. To test this hypothesis, the
benzoazepine derivatives shown in Table 1 were char-
acterized in vitro in terms of affinity to the glycine
binding site. From the newly reported derivatives (Table
1) and from previously reported results [26], the follow-
ing general comments can be addressed: (a) signs of
activity were observed when an H-bond donor groups
loss of affinity (Kiꢀ
and CONH2, respectively), the benzazepine derivative
27 and 28b (RꢀCOOH and CONH2) show comparable
/
3 nM and ꢀ
/
105, for Rꢀ
/COOH
/
in vitro activity. As a result, a different positioning of
the indole and the benzazepine template within the
glycine binding site pocket could be hypothesized.
5. Pharmacological characterization
The most in vitro potent benzazepine derivatives
(KiB100 nM) were tested in the NMDA-induced
/
convulsions in mice by i.v. route. The research complied
with national legislation and with company policy on
the Care and Use of Animals and with related codes of
practice.
As shown in Table 1, all the compounds selected,
(entry 27, 28a, 28b and 28c) exhibited good in vivo
activity (greater than 30% inhibition of convulsion
induced by the icv injection of NMDA). When the
most potent compound of this series, the free carboxyl
derivative 27, was tested in the range of doses between
0.001 and 3 mg/kg, a dose-dependent inhibition of
convulsions was observed reaching 80% of inhibition
(Rꢀ
/
OH and NHSO2CF3, entry 11 and 19b, Kiꢀ1288
/
and 2692 nM, respectively) were introduced in this
position; (b) a significant improvement in terms of in
vitro affinity was observed with free carboxyl group
confirming the working hypothesis (Rꢀ/COOH, entry
27, Kiꢀ32 nM); (c) notably, a comparable in vitro
/
affinity to compound 27 was observed when the free
acid was transformed into the corresponding hydro-
at 3 mg/kg, i.v. (ED50 byꢀ0.07 mg/kg). As previously
reported [26], compound 27 was further progressed
throughout the screening cascade assessing in vitro
/
xamic acid (Rꢀ
/
CONHOH, entry 28a, Kiꢀ44 nM) or
/

R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á
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738
729
both the degree of non-competitive antagonism and the
glutamate receptor selectivity.
was found to be still effective when its administration
was delayed up to 6 h after the occlusion of the middle
cerebral artery.
Therefore, as GV150526, compound 27 was able to
block the progression of the cerebral damage even at
delayed times from occlusion.
In vitro, this compound exhibited more than 1000-
fold receptor selectivity for the strychnine-insensitive
glycine binding site with respect to other glutamate
binding sites (Kiꢀ
105 for the NMDA, AMPA and
/
kainate binding site, respectively). Moreover, by inhibi-
tion studies of the binding of [3H]TCP in extensively
washed cortical membranes preparation, this compound
was confirmed to be a non-competitive antagonist
acting at the glycine binding site with an estimated
pA2 of 6.4.
7. Experimental
7.1. Chemistry
In the permanent MCAo model in rats, a significant
neuroprotective effect was observed after both pre- and
post-ischaemia administration. In the pre-ischaemia
protocol (compound administered 5 min prior occlu-
sion), as shown in Table 2, compound 27, show a dose-
dependent neuroprotective effect in the range between
0.1 and 3 mg/kg, i.v., with a maximal protection of 66%
In the preparations and examples, unless otherwise
stated: melting points (m.p.) were determined on a Buchi
¨
melting point apparatus and are uncorrected. All
temperatures refer to 8C. Infrared spectra were mea-
sured on a Bruker IFS 48 (FT) spectrometer in chloro-
form-d1 solutions or in Nujol mull. Proton magnetic
resonance (1H NMR) spectra were recorded either on a
Varian PFG JNOVA 400 operating at 400 MHz or on a
Varian VXRS 5000 operating at 300 MHz. Chemical
shifts are expressed as d units (part per million) down-
field from Me4Si and are assigned as singlets (s),
doublets (d), doublet of doublets (dd), or multiplets
(m). Mass spectra were recorded on a VG-4 triple
quadrupole Fisons instrument. Elemental analyses (C,
H, N) were performed by our analytical group on a
CHNS-O EA-1108 Elemental Analyser and were within
observed at 3 mg/kg (ED50ꢀ0.6 mg/kg). Post-ischae-
/
mia, a significant neuroprotective effect was seen at 2.5
mg/kg dose, when compound 27 was given as a single
bolus, up to 6 h from occlusion. In these conditions a
significant reduction of the volume of brain infarct
(41%) was observed with respect to the control animals.
6. Conclusions
90.4% of the theoretical values. TLC refers to the thin-
/
layer chromatography on silica gel plates using Merck
silica gel 60, F254 plates. Column chromatography was
A class of glycine antagonists was designed by
receptor mapping studies based on the pharmacophore
model of the glycine binding site. A number of new
derivatives were produced and new synthetic pathways
designed. Notably, the in vitro affinity of this class of
compounds was optimized by suitable modulation of the
C-3 position. In particular, it was observed that the
presence of an H-bond donor and/or a charged group in
the position C-3, was found to be crucial to maximize
the binding of the benzazepine template to the glycine
site, gathering additional information on the glycine
binding site associated to the NMDA receptor. Among
the different compounds prepared, the free carboxyl
derivative 27 confirmed [26] its outstanding neuropro-
tective profile when given both pre- and post-ischaemia
in the MCAo model in rats. Notably, post-ischaemia, it
carried out over silica gel 60 (230Á400 mesh, G60
/
Merck). Reagents were used as received unless otherwise
stated.
7.2. 2-Bromo-5-chloro-aniline (1)
Iron powder (0.944 g, 16.9 mmol) was added to a
solution of 2-bromo-5-chloronitrobenzene (1.5 g, 4.22
mmol) in AcOH/EtOH (14/14 ml) and the reaction
mixture was heated at 100 8C for 1 h. Then, a saturated
solution of NaHCO3 was added and the resulting
mixture was extracted with EtOAc. The organic phase
was washed with brine, dried and evaporated under
reduced pressure. The oil residue was purified by flash
chromatography (eluant cyclohexane/EtOAc 8:2), yield-
ing compound 1 as a brown oil (1.24 g, 97%): 1H NMR
d (CDCl3): 7.30 (d, 1H); 6.75 (d, 1H); 6.59 (dd, 1H); 4.14
(bs, 2H); IR (CDCl3) nmax. (cmꢁ1): 3493 and 3396
(NH2); MS (EI/positive): m/z 205 [M; 1Br]ꢂ. Anal.
(C6H5BrClN) C, H, N.
Table 2
Pharmacological profile of 27
27
GV150526
MCAo model
Pre-ischaemia
Post-ischaemia
ED50
0.6 mg/kg
2.5 mg/kg a
0.8 mg/kg
3 mg/kg a
7.3. a-(Diphenyl-tert-butylsilyloxy)-butyrolactone (2)
a
To a solution of a-hydroxy-butyrolactone (0.8 g, 7.84
mmol) in DMF (30 ml) were added diphenyl-tert-
Single full protective dose given 6 h after occulsion. i.v. admin-
istration.

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R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á738
/
butyldiphenylchlorosilane (4.07 ml, 15.9 mmol) and
N,N-dimethylaminopyridine (0.095 g). The reaction
mixture was stirred at room temperature (r.t.) for 12
h, then diluted with brine and extracted with EtOAc.
The organic phase was collected and washed with brine,
dried and evaporated under reduced pressure. The crude
residue was purified by flash chromatography (eluant
cyclohexane/EtOAc 95:5) to give compound 2 as colour-
(cmꢁ1): 3366 (NH), 1705 (CÄ
662 [Mꢂ
H]ꢂ. Anal. (C32H43BrClNO3Si2) C, H, N.
/
O); MS (FAB/NBA): m/z
/
7.6. N-(2-Bromo-5-chlorophenyl)-N-(4-
methoxybenzyl)-2-(diphenyl-tert-butylsilyloxy)-4-
(dimethyl-tert-butylsilyloxy)-butyramide (5)
To a solution of intermediate 4 (0.5 g, 0.76 mmol) in
DMF (20 ml) was added NaH 60% (0.04 g, 1.0 mmol)
and the reaction mixture was stirred at r.t. for 30 min.
Then, 4-methoxybenzyl chloride (0.16 g, 1 mmol) and
sodium iodide (0.12 g, 0.83 mmol) were added. The
reaction mixture was heated at 80 8C for 2 h, then
diluted with water and extracted with EtOAc. The
organic phase was washed with brine, dried and
evaporated under reduced pressure. The crude residue
was purified by flash chromatography (eluant cyclohex-
ane/EtOAc 8:2) to give compound 5 as colourless oil (0.3
1
less oil (2 g, 75%): H NMR d (DMSO-d6): 7.80 (dd,
2H); 7.69 (dd, 2H); 7.5Á
(m, 1H); 4.01 (ddd, 1H); 2.32Á
IR (Nujol) nmax. (cmꢁ1): 1790 (CÄ
m/z 283 [Mꢁ
tBu]ꢂ; 340 [Mꢂ
(C20H24O3Si) C, H.
/
7.35 (m, 6H); 4.36 (dd, 1H); 4.31
2.12 (m, 2H); 1.10 (s, 9H);
O); MS (FAB/NBA):
H] defective. Anal.
/
/
/
/
7.4. N-(2-Bromo-5-chlorophenyl)-2-(diphenyl-tert-
butylsilyloxy)-4-hydroxy-butyramide (3)
1
To a solution of intermediate 1 (25 g, 12.1 mmol) in
CH2Cl2 (80 ml) was added dropwise a 1 M solution of
Et2AlCl (18 ml, 18 mmol) in hexane. After 30 min, the
reaction mixture was cooled to 0 8C and a solution of
intermediate 2 (4.5 g, 13.3 mmol) in CH2Cl2 (40 ml) was
carefully added. The resulting solution was stirred at r.t.
for 3 h, then diluted with brine and extracted with
EtOAc. The organic phase was washed with a 1 N
solution of HCl, dried and evaporated under reduced
pressure. The crude residue was purified by flash
chromatography (eluant cyclohexane/EtOAc 8:2) to
give compound 3 as white solid (2.6 g, 40%): m.p.
g, 51%): H NMR d (CDCl3): 7.63 (dd, 2H); 7.54 (dd,
2H); 7.40 (d, 1H); 7.4Á
(d, 2H); 6.71 (d, 2H); 5.68 (d, 1H); 5.25 (d, 1H); 4.1 (dd,
1H); 4.00 (d, 1H); 3.79 (s, 3H); 3.62Á3.48 (m, 2H); 1.84
(m, 2H); 1.03 (s, 9H); 0.76 (s, 9H); ꢁ0.098 (s, 3H); ꢁ0.1
(s, 3H); IR (CDCl3) nmax. (cmꢁ1): 1674 (CÄ
(FAB/NBA): m/z 780 [Mꢂ
H]ꢂ.
(C40H51BrClNO4Si2) C, H, N.
/
7.23 (m, 6H); 7.00 (dd, 1H); 6.87
/
/
/
/
O); MS
/
Anal.
7.7. N-(2-Bromo-5-chlorophenyl)-2-(diphenyl-tert-
butylsilyloxy)-4-hydroxy-N-(4-methoxybenzyl)-
butyramide (6)
163Á
1H); 7.71 (dd, 2H); 7.63 (dd, 2H); 7.52Á
7.00 (dd, 1H); 4.47 (dd, 1H); 3.6 (m, 2H); 1.96 (dd, 1H);
2.00Á1.85 (m, 1H); 1.85Á1.7 (m, 1H); 1.2 (s, 9H); IR
(CDCl3) nmax. (cmꢁ1): 1691 (CÄ
O); MS (FAB/NBA): m/
z 456 [Mꢂ
H]ꢂ. Anal. (C26H29BrClNO3Si) C, H, N.
/
165 8C; 1H NMR d (CDCl3): 9.24 (bs, 1H); 8.44 (d,
7.32 (m, 7H);
/
To a solution of intermediate 5 (1.9 g, 2.43 mmol) in
MeOH (50 ml) was added p-toluensolphonic acid (0.278
g, 1.46 mmol) and the reaction mixture was stirred at r.t.
for 1 h. The reaction mixture was poured into a buffered
phosphate solution pH 7, the organic phase was
extracted with EtOAc, dried and evaporated under
reduced pressure. The crude residue was purified by
flash chromatography (eluant cyclohexane/EtOAc 8:2)
/
/
/
/
7.5. N-(2-Bromo-5-chlorophenyl)-2-(diphenyl-tert-
butylsilyloxy)-4-(dimethyl-tert-butylsilyloxy)-
butyramide (4)
1
to give compound 6 as white foam (1.17 g, 72%): H
NMR d (CDCl3): 7.58 (m, 2H); 7.53 (m, 2H); 7.42 (d,
To a solution of intermediate 3 (2.6 g, 4.76 mmol) in
DMF (47 ml) were added tert-butyldimethylsilylchlor-
ide (1.43 g, 9.5 mmol), imidazole (3.24 g, 47.6 mmol)
and a catalytic amount of dimethylaminopyridine (0.058
g, 0.47 mmol). The reaction mixture was stirred at r.t.
for 12 h, then diluted with brine and extracted with
EtOAc. The organic phase was washed with brine, dried
and evaporated under reduced pressure. The crude
residue was purified by flash chromatography (eluant
cyclohexane/EtOAc 9:1) to give compound 4 as colour-
less oil (3.36 g, 99%): 1H NMR d (CDCl3): 9.13 (s, 1H);
1H); 7.38 (m, 2H); 7.3Á7.2 (m, 4H); 7.03 (dd, 1H); 7.01
(m, 2H); 6.79 (m, 2H); 5.57 (d, 1H); 5.37 (d, 1H); 4.08 (t,
1H); 4.00 (d, 1H); 3.82 (s, 3H); 3.80 (m, 1H); 3.64 (m,
/
1H); 2.12 (t, 1H); 1.75 (m, 2H); 1.07Á
(FAB/NBA): m/z 666 [Mꢂ
(C34H37BrClNO4Si) C, H, N.
/
1.06 (2s, 9H); MS
/
H]ꢂ.
Anal.
7.8. N-(2-Bromo-5-chlorophenyl)-2-(diphenyl-tert-
butylsilyloxy)-N-(4-methoxybenzyl)-4-oxo-butyramide
(7)
8.50 (d, 1H); 7.70 (m, 2H); 7.61 (m, 2H); 7.5Á
7H); 6.95 (dd, 1H); 4.45 (dd, 1H); 3.72 (m, 1H); 3.58 (m,
1H); 2.00 (m, 1H); 1.62Á1.52 (m, 1H); 1.17 (s, 9H); 0.76
(s, 9H); 0.098 (s, 3H); ꢁ0.1 (s, 3H); IR (Nujol) nmax.
/
7.3 (m,
At ꢁ78 8C, oxalylchloride (0.19 ml, 2.25 mmol) was
/
added to a solution of DMSO (0.32 ml, 4.5 mmol) in
CH2Cl2 (20 ml) and the solution was stirred at the same
temperature for 20 min. Then a solution of intermediate
/
/

R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á
/
738
731
6 (0.6 g, 0.9 mmol) in CH2Cl2 (15 ml) and TEA (0.62 ml,
4.5 mmol) were added and the solution was warmed to
7.11. 2-[8-Chloro-(4-methoxybenzyl)-2-oxo-3-
(diphenyl-tert-butylsilyloxy)-1,2,3,4-tetrahydro-benzo-
[b]-azepin-5-ylidene)]-N-phenyl-acetamide (10a)
ꢁ20 8C. After 30 min a 3 N solution of HCl (20 ml) was
/
added. The organic phase was extracted with CH2Cl2,
dried and evaporated under reduced pressure. The crude
residue was purified by flash chromatography (eluant
cyclohexane/EtOAc 8:2) to give compound 7 as colour-
less oil (0.45 g, 75%): 1H NMR d (CDCl3): 9.77 (m, 1H);
To a suspension of intermediate 9 (0.25 g, 3.02 mmol)
in MeCN (90 ml) was added TEA (0.84 ml, 6.04 mmol)
and Pd(PPh3)4 (0.17 g, 0.15 mmol). The reaction mixture
was heated at reflux for 24 h, then poured into saturated
solution of ammonium chloride and extracted with
EtOAc. The organic phase was washed with brine, dried
and evaporated under reduced pressure. The crude
material was purified by flash chromatography (eluant
cyclohexane/EtOAc 7:3) to obtain compound 10a as
7.58 (d, 2H); 7.45 (d, 2H); 7.42Á7.2 (m, 7H); 7.02 (dd,
/
1H); 7.00 (m, 2H); 6.78 (d, 2H); 5.71 (d, 1H); 5.19 (d,
1H); 4.25 (t, 1H); 4.11 (d, 1H); 3.81 (s, 3H); 2.67 (ddd,
1H); 2.52 (ddd, 1H); 1.003 (s, 9H); MS (FAB/NBA): m/z
664 [Mꢂ
H]ꢂ. Anal. (C34H35BrClNO4Si) C, H, N.
/
white foam (0.52 g, 77%): 1H NMR d (CDCl3): 7.6Á
(m, 4H); 7.55Á7.3 (m, 10H); 7.21 (d, 1H); 7.16Á7.1 (m,
1H); 7.07 (d, 2H); 6.97 (d, 2H); 6.78 (d, 1H); 6.73 (d,
2H); 6.69 (d, 2H); 6.62 (bs, 1H); 5.44Á5.40 (d, 1H); 5.05
(d, 1H); 4.91 (d, 1H); 4.56 (dd, 1H); 4.30 (dd, 1H); 4.22Á
4.02 (m, 3H); 3.89 (d, 1H); 3.69Á3.66 (s, 3H); 2.95 (tt,
1H); 2.74 (tt, 1H); 1.10/0.82 (s, 9H); IR (CDCl3) nmax.
(cmꢁ1): 1682 (CÄ
O); MS (FAB/NBA): m/z 700 [Mꢂ
H]ꢂ. Anal. (C42H41ClN2O4Si) C, H, N.
/
7.57
/
/
7.9. 6-[(2-Bromo-5-chlorophenyl)-(4-methoxybenzyl)-
carbamoyl)-5-(diphenyl-tert-butylsilyloxy)-(E)-hex-2-
enoic acid ethyl ester (8)
/
/
To a solution of intermediate 7 (0.4 g, 0.6 mmol) in
toluene (20 ml) was added (ethoxycarbonylmethylen)-
triphenylphosphorane (0.21 g, 0.6 mmol). The reaction
mixture was heated at 70 8C for 2 h, then the solvent was
evaporated and the crude residue was purified by flash
chromatography (eluant cyclohexane/EtOAc 9:1) to
/
/
/
The endo isomer 10b was also isolated as white foam
(0.087 g, 13%).1H NMR d (CDCl3): 7.69 (m, 3H); 7.6
1
afford compound 8 as colourless oil (0.35 g, 80%): H
(d, 2H); 7.44Á7.12 (m, 12H); 7.06 (dd, 1H); 7.00 (d, 1H);
/
NMR d (CDCl3): 7.55 (dd, 2H); 7.45 (dd, 2H); 7.4Á7.2
/
6.84 (d, 2H); 6.65 (d, 2H); 6.21 (d, 1H); 4.82 (m, 2H);
(m, 7H); 7.03 (dd); 7.00 (d, 2H); 6.77 (d, 2H); 6.67 (dt,
1H); 5.71 (d, 1H); 5.70 (d, 1H); 5.23 (d, 1H); 4.15 (q,
2H); 4.07 (d, 1H); 3.87 (m, 1H); 3.81 (s, 3H); 2.56 (m,
2H); 1.28 (t, 3H); 1.02 (s, 9H); MS (FAB/NBA): m/z 734
4.32 (d, 1H); 3.69 (s, 3H); 3.52 (d, 1H); 3.34 (d, 1H); 1.13
(s, 9H); IR (Nujol) nmax. (cmꢁ1): 1691 and 1664 (CÄ
MS (FAB/NBA): m/z 700 [Mꢂ
H]ꢂ. Anal.
(C42H41ClN2O4Si) C, H, N.
/
O);
/
[Mꢂ
H]ꢂ. Anal. (C38H41BrClNO5Si) C, H, N.
/
7.10. (E)-Hex-2-enedioic acid, 6-[(2-bromo-5-
chlorophenyl)-(4-methoxybenzyl)-amide]-5 (diphenyl-
tert-butylsilyloxy)-1-phenylamide (9)
7.12. 2-[6-Chloro-2-oxo-3-hydroxy-1,2,3,4-tetrahydro-
benzo-[b]-azepin-5-ylidene)]-N-phenyl-acetamide (11)
To a solution of intermediate 10a (0.1 g, 0.22 mmol)
in CF3COOH (8.6 ml) were added anisole (234 ml) and
12 N H2SO4 (359 ml). The reaction mixture was heated
at 80 8C for 1 h, then poured into crushed ice. Saturated
solution of NaHCO3 was added until pH 7 and the
resulting solution was extracted with EtOAc, washed
with brine, dried and evaporated under reduced pres-
sure. The crude residue was purified by flash chromato-
graphy (eluant cyclohexane/EtOAc) to obtain
To a solution of aniline (0.22 ml, 2.44 mmol) in
CH2Cl2 (10 ml) was added Et2AlCl (1 M solution in
hexane, 3.67 ml, 3.67 mmol). The reaction mixture was
stirred at r.t. for 30 min, then a solution of intermediate
8 (0.9 g, 1.22 mmol) in toluene (20 ml) was added and
the resulting solution was heated at 80 8C for 1 h. A 1 M
solution of HCl (20 ml) was added and the mixture was
extracted with CH2Cl2; the organic phase was washed
with brine, dried and evaporated under reduced pres-
sure. The crude material was purified by flash chroma-
tography (eluant cyclohexane/EtOAc 8:2) to give
compound 11 as white solid (0.05 g, 67%): m.p. 243Á
/
1
245 8C; H NMR d (acetone-d6): 9.33 (bs, 2H); 7.72 (d,
2H); 7.44 (d, 1H); 7.34Á7.23 (m, 3H); 7.22 (d, 1H); 7.06
(t, 1H); 6.1 (dd, 1H); 4.45 (m, 1H); 3.98 (d, 1H); 3.79
(ddd, 1H); 3.60 (ddd, 1H); IR (Nujol) nmax. (cmꢁ1)
3441Á3198 (NH), 1670 and 1661 (CÄO); MS (FAB/
NBA): m/z 343 [Mꢂ
H]ꢂ. Anal. (C18H15ClN2O3) C, H,
N.
1
compound 9 as colourless oil (0.744 g, 78%): H NMR
/
d (CDCl3): 7.6Á7.06 (m, 18H); 7.03 (d, 2H); 6.79 (d,
/
2H); 6.53 (m, 1H); 5.83 (d, 1H); 5.79 (d, 1H); 5.30 (d,
1H); 4.06 (d, 1H); 3.92 (t, 1H); 3.81 (s, 3H); 2.56 (m,
2H); 1.02 (s, 9H); IR (CDCl3) nmax. (cmꢁ1): 1678 and
:
/
/
1603 (CÄ
/
O); MS (FAB/NBA): m/z 781 [Mꢂ
H]ꢂ. Anal.
/
/
(C42H42BrClN2O4Si) C, H, N.

732
R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á738
/
7.13. N-(4-Methoxy-benzyl)-2-bromo-5-chloro aniline
(12)
(m, 1H); MS (FAB/NBA): m/z 559 [Mꢂ
(C26H24BrClN2O5) C, H, N.
/
H]ꢂ. Anal.
To a solution of intermediate 1 (2 g, 9.7 mmol) in
DMF (35 ml) were added 4-methoxybenzylchloride
(1.45 ml, 10.68 mmol) and NaI (1.6 g, 10.68 mmol).
The reaction mixture was heated at 80 8C for 2 h, then
diluted with water and extracted with EtOAc. The
organic phase was washed with brine, dried and
evaporated under reduced pressure. The crude residue
was purified by flash chromatography (eluant petro-
7.16. (E)-5-Benzyloxycarbonylamino-5-[(2-bromo-5-
chloro-phenyl)-(4-methoxy-benzyl)-carbamoyl]-pent-2-
enoic acid tert-butyl ester (15)
To a solution of intermediate 14 (1.4 g, 2.5 mmol) in
toluene (25 ml) was added (tert-butoxycarbonyl meth-
ylene)-triphenyl phosphorane (1.035 g, 2.75 mmol) and
the reaction mixture was heated at reflux for 2 h. The
solvent was evaporated under reduced pressure and the
crude residue was purified by flash chromatography
(eluant cyclohexane/EtOAc 80:20) to give the title
compound 15 as pale yellow oil (1.5 g, 92%); 1H
leum/Et2O 98:2) to give compound 12 as yellow oil (2.2
1
g, 70%): m.p. 67Á
/
69 8C; H NMR d (CDCl3): 7.32 (d,
1H); 7.28 (d, 2H); 6.90 (d, 2H); 6.60 (d, 1H); 6.55 (dd,
1H); 4.69 (t, 1H); 4.29 (d, 2H); 3.82 (s, 3H); IR (Nujol)
nmax. (cmꢁ1): 3408 (NH); MS (EI/positive): m/z 325 [M,
1Br]ꢂ. Anal. (C14H13BrClNO) C, H, N.
NMR d (acetone-d6): 7.8 (d, 1H); 7.4Á
7.14 (m, 2H); 6.80 (m, 3H); 6.68 (m, 1H); 5.75 (dt, 1H);
5.51 (d, 1H); 5.03 (s, 2H); 4.3Á4.1 (m, 2H); 3.77 (s, 3H);
2.66 (m, 1H); 2.53 (m, 1H); 1.45 (s, 9H); MS (FAB/
NBA): m/z 657 [Mꢂ
H]ꢂ. Anal. (C32H34BrClN2O6) C,
H, N.
/7.28 (m, 6H);
/
7.14. {1-[(2-Bromo-5-chloro-phenyl)-(4-methoxy-
benzyl)-carbamoyl]-but-3-enyl}-carbamic acid benzyl
ester (13)
/
To a solution of N-benzyloxycarbonyl-allylglycyl
7.17. (E)-{1-[(2-Bromo-5-chloro-phenyl)-(4-methoxy-
benzyl)-carbamoyl]-4-phenylcarbamoyl-but-3-enyl}-
carbamic acid benzyl ester (16)
chloride (1.85 g, 6.9 mmol) in CH2Cl2, cooled to ꢁ
/
40 8C, were added a solution of intermediate 12 (1.5 g,
4.6 mmol) in THF (25 ml) and Py (560 ml, 6.9 mmol).
The reaction mixture was slowly warmed to r.t. and
stirred for 12 h, then diluted with a saturated solution of
NaHCO3 and extracted with EtOAc. The organic phase
was washed with brine, dried and evaporated under
reduced pressure. The crude residue was purified by
flash chromatography (eluant cyclohexane/EtOAc
80:20) to give compound 13 as white foam (2 g, 78%):
To a solution of intermediate 15 (1.5 g, 2.3 mmol) was
added HCOOH (16 ml) and the reaction mixture stirred
at r.t. for 2 h. The solvent was evaporated under reduced
pressure and the crude residue was diluted with CH2Cl2,
washed with brine, dried and evaporated under reduced
pressure. The crude residue (1.3 g, 2.1 mmol) was
dissolved in DMF (20 ml), then 1-hydroxybenzotriazole
(0.315 g, 2.6 mmol), dicyclohexylcarbodiimide (0.54 g,
2.6 mmol) and aniline (0.236 ml, 2.6 mmol) were added.
The reaction mixture was stirred at r.t. for 12 h then
diluted with EtOAc, washed with a 1 N solution of HCl
dried and evaporated under reduced pressure. The crude
compound was triturated with Et2O/petroleum (8/8 ml)
1H NMR d (acetone-d6): 7.8 (d, 1H); 7.4Á
7.18 (m, 2H); 6.85 (d, 1H); 6.61 (d, 1H); 5.76Á
1H); 5.55 (d, 1H); 5.6Á4.94 (m, 4H); 4.20 (d, 1H); 4.16
(m, 1H); 3.77 (s, 3H); 2.48 (m, 1H); 2.32 (m, 1H); IR
(CDCl3) nmax. (cmꢁ1): 1682 (CÄ
O); MS (FAB/NBA): m/
z 557 [Mꢂ
H]ꢂ. Anal. (C27H26BrClN2O4) C, H, N.
/
7.3 (m, 6H);
5.60 (m,
/
/
/
/
1
to give compound 16 as white solid (1.13 g, 80%): H
7.15. {1-[(2-Bromo-5-chloro-phenyl)-(4-methoxy-
benzyl)-carbamoyl]-3-oxo-propyl}-carbamic acid benzyl
ester (14)
NMR d (acetone-d6): 9.22 (s, 1H); 7.8Á
7.40Á7.0 (m, 12H); 6.84Á6.7 (m, 4H); 6.13 (d, 1H); 5.53
(d, 1H); 5.03 (s, 2H); 4.15 (m, 2H); 3.76 (s, 3H); 2.8Á2.4
(m, 2H); IR (Nujol) nmax. (cmꢁ1): 3323 (NH), 1720
and1661 (CÄO); MS (FAB/NBA): m/z 676 [Mꢂ
H]ꢂ.
Anal. (C34H31BrClN3O5) C, H, N.
/7.6 (m, 3H);
/
/
/
Ozone was bubbled through a cooled (ꢁ78 8C)
/
/
/
solution of intermediate 12 (2 g, 3.6 mmol) in CH2Cl2
(40 ml) until a pale blue color appeared (approximately
30 min). Then, PPh3 (1.4 g, 5.4 mmol) was added and
the reaction mixture stirred at r.t. for 2 h. The solvent
was evaporated under reduced pressure and the crude
residue was purified by flash chromatography (eluant
cyclohexane/EtOAc 80:20) to give compound 14 as
7.18. (E)-[8-Chloro-1-(4-methoxy-benzyl)-2-oxo-5-
phenylcarbamoylmethylene-2,3,4,5-tetrahydro-1H-
benzo[b]azepin-3-yl]-carbamic acid benzyl ester (17)
1
white foam (1.5 g, 74%): H NMR d (CDCl3): 9.71 (s,
To a solution of intermediate 16 (1.1 g, 1.6 mmol) in
DMF (15 ml) were added Pd(PPh3)4 (0.093 g, 0.08
mmol) and TEA (0.45 ml, 3.2 mmol). The reaction
mixture was heated at 110 8C for 2 h, then diluted with
1H); 7.8 (d, 1H); 7.45Á
/
7.3 (m, 6H); 7.22Á7.1 (m, 2H);
/
6.94 (d, 1H); 6.9 (d, 1H); 5.53 (d, 1H); 4.9 (m, 2H); 4.74
(m, 1H); 4.15 (d, 1H); 3.79 (s, 3H); 3.13 (dd, 1H); 2.69

R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á
/
738
733
brine and extracted with EtOAc. The organic layer was
dried, evaporated and the crude residue was purified by
flash chromatography (eluant cyclohexane/EtOAc
80:20) to give compound 17 as white solid (0.57 g,
2H); 8.52 (s, 1H); 7.8 (d, 1H); 7.74 (d, 2H); 7.50 (d, 1H);
7.37 (dd, 1H); 7.35 (t, 2H); 7.30 (d, 1H); 7.11 (t, 1H);
6.20 (t, 1H); 4.60 (dd, 1H); 4.26 (dd, 1H); 3.59 (m, 1H);
MS (FAB/NBA): m/z 474 [Mꢂ
/
H]ꢂ. Anal.
1
60%): H NMR d (acetone-d6): 9.21 (s, 1H); 7.73 (d,
(C19H15ClF3N3O4S) C, H, N.
2H); 7.57 (d, 1H); 7.4Á7.2 (m, 9H); 7.09 (d, 2H); 7.08 (t,
/
1H); 6.74 (d, 2H); 6.67 (d, 1H); 5.83 (dd, 1H); 5.48 (d,
1H); 5.08 (s, 2H); 4.6 (d, 1H); 4.60 (m, 1H); 4.11(dd,
7.22. (5-Chloro-2-iodo-phenyl)-(4-methoxy-benzyl)-
amine (21)
1H); 3.66 (s, 3H); 3.30 (m, 1H); IR (Nujol) nmax. (cmꢁ1)
:
O); MS (FAB/NBA): m/z 596
3325 (NH), 1720 (CÄ
/
Compound 21 was prepared using the same methods
as compound 12 and obtained, after purification by
flash column chromatography (eluant petroleum/Et2O
98:2), as colourless oil (3.37 g, 66%): 1H NMR d
(CDCl3): 7.55 (1H, d); 7.27 (2H, d); 6.90 (2H, d); 6.52
(1H, d); 6.45 (1H, dd); 4.55 (1H, t); 4.28 (2H, d); 3.81
[Mꢂ
/
H]ꢂ. Anal. (C34H30ClN3O5) C, H, N.
7.19. (E)-2-(3-Amino-8-chloro-2-oxo-1,2,3,4-
tetrahydro-benzo[b]azepin-5-ylidene)-N-phenyl-
acetamide (18)
(3H, s); MS (FAB/NBA): m/z 373 [Mꢂ
/
H]ꢂ. Anal.
Compound 18 was prepared using the same methods
as compound 11 and used without further purification:
(C14H13ClINO) C, H, N.
MS (FAB/NBA): m/z 342 [Mꢂ
H]ꢂ.
/
7.23. N-(5-Chloro-2-iodo-phenyl)-N-(4-methoxy-
benzyl)-malonamic acid methyl ester (22)
7.20. (E)-2-(8-Chloro-3-methanesulfonylamino-2-oxo-
1,2,3,4-tetrahydro-benzo[b]azepin-5-ylidene)-N-phenyl-
acetamide (19a)
To a solution of intermediate 21 (3.37 g, 8.61 mmol)
in toluene (60 ml), cooled to 0 8C, were added Py (0.91
ml, 11.5 mmol) and methyl malonyl chloride (1.2 ml,
11.19 mmol). The solution was stirred at 0 8C for 45
min, then poured into brine and extracted with EtOAc.
The organic phase was washed with 0.5 N solution of
HCl, dried and evaporated under reduced pressure. The
crude residue was purified by flash column chromato-
To a solution of intermediate 18 (0.1 g, 0.29 mmol) in
THF (10 ml) was added TEA (0.061 ml, 0.44 mmol) and
the reaction mixture was cooled to ꢁ78 8C. Trifluor-
/
omethanesulphonic anhydride (0.137 ml, 0.29 mmol)
was added and the mixture stirred for 1 h, then diluted
with a saturated solution of NH4Cl and extracted with
EtOAc. The organic layer was washed with brine, dried
and evaporated under reduced pressure. The crude
residue was purified by flash chromatography (eluant
cyclohexane/EtOAc 80:20) to give compound 19a as
graphy (eluant cyclohexane/EtOAc 9:1Á8:2) to afford
/
compound 22 as colourless solid (4.0 g, 97%): 1H NMR
d (CDCl3): 7.84 (1H, d); 7.13 (2H, d); 7.06 (1H, dd); 6.82
(2H, d); 6.75 (1H, d); 5.52 (1H, d); 3.96 (1H, d); 3.79
(3H, s); 3.68 (3H, s); 3.18 (1H, d); 3.04 (1H, d); IR
white solid (0.103 g, 75%): m.p. 225Á
227 8C; 1H NMR d
/
(Nujol): nmax. (cmꢁ1): 1734 and 1664 (CÄ
Thiogly.): m/z 474 [Mꢂ
H]ꢂ. Anal. (C18H17ClINO4) C,
H, N.
/O); MS (FAB/
(acetone-d6): 9.33 (s, 1H); 9.30 (s, 1H); 7.71 (d, 2H); 7.45
(d, 1H); 7.32 (m, 2H); 7.30 (dd, 1H), 7.22 (d, 1H); 7.07
(m, 1H); 6.43 (d, 1H); 6.13 (m, 1H); 4.49 (m, 1H); 4.04
(m, 1H); 3.57 (m, 1H); 2.93 (s, 3H); MS (FAB/NBA): m/
/
z 420 [Mꢂ
/
H]ꢂ. Anal. (C19H18ClN3O4S) C, H, N.
7.24. N-(5-Chloro-2-iodo-phenyl)-N-(4-methoxy-
benzyl)-malonamic acid (23)
7.21. (E)-2-(8-Chloro-2-oxo-3-
trifluoromethanesulfonylamino-1,2,3,4-tetrahydro-
benzo[b]azepin-5-ylidene)-N-phenyl-acetamide (19b)
To a solution of intermediate 22 (3.99 g, 8.42 mmol)
in THF (85 ml) was added 1 M solution of LiOH in
water (16.85 ml, 16.5 mmol). The reaction was stirred at
r.t. for 18 h, then poured into a saturated solution of
NH4Cl and acidified to pH 2 with 2 M solution of HCl.
The solution was extracted with EtOAc and the organic
phase was washed with brine, dried and evaporated
under reduced pressure, obtaining compound 23 as
To a solution of intermediate 18 (0.1 g, 0.29 mmol) in
THF (10 ml) was added TEA (0.061 ml, 0.44 mmol) and
the reaction mixture was cooled to 0 8C. CH3SO2Cl
(0.025 ml, 0.319 mmol) was added and the mixture
stirred for 1 h, then diluted with a saturated solution of
NH4Cl and extracted with EtOAc. The organic layer
was washed with brine, dried and evaporated under
reduced pressure. The crude residue was purified by
flash chromatography (eluant cyclohexane/EtOAc
50:50) to give compound 19b as white solid (0.06 g,
colourless solid (3.56 g, 92%): m.p. 132Á
133 8C; 1H
/
NMR d (CDCl3): 7.87 (1H, d); 7.14 (1H, dd), 7.09 (2H,
d); 6.84 (2H, d); 6.69 (1H, d); 5.50 (1H, d); 4.03 (1H, d);
3.81 (3H, s); 3.02 (2H, s); IR (Nujol) nmax. (cmꢁ1): 1738
(CÄ
/
O); MS (EI/positive): m/z 459 [M]ꢂ. Anal.
80%): m.p. 240Á
242 8C;1H NMR d (acetone-d6): 9.40 (s,
/
(C17H15ClINO4) C, H, N.

734
R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á738
/
7.25. N-(5-Chloro-2-iodo-phenyl)-N-(4-methoxy-
benzyl)-malonamic acid tert-butyl ester (24)
d); 4.82 (1H, d); 3.88 (1H, bs); 3.71 (1H, t); 3.64 (3H, s);
3.5 (1H, bs); 1.4 (9H, bs); IR (Nujol) nmax. (cmꢁ1): 3290
and 3130 (NH); 1736 (CÄ
/
O); MS (FAB/NBA): m/z 547
A solution of intermediate 23 (2.30 g, 5.00 mmol) in
CH2Cl2 (75 ml) was cooled to 0 8C, then were added 4-
(dimethylamino)pyridine (0.30 g, 2.45 mmol), 2-methyl-
2-propanol (0.93 g, 12.54 mmol) and 1-[-3-(dimethyla-
mino)propyl]-3-ethylcarbodiimide hydrochloride (1.29
g, 6.72 mmol). The mixture was stirred for 15 min at
0 8C and then at r.t. for 1 h. The reaction mixture was
diluted with EtOAc, washed with 5% solution of
NaHCO3 and brine, dried and concentrated. The crude
residue was purified by flash column chromatography
[Mꢂ
/
H]ꢂ. Anal. (C31H31ClN2O5) C, H, N.
7.28. (E)-8-Chloro-2-oxo-5-phenylcarbamoylmethylene-
1,2,3,4-tetrahydro-1H-benzo[b]azepine 3-carboxylic acid
(27)
Compound 27 was prepared using the same methods
as compound 11 and obtained as white solid (0.03 g,
1
74%): H NMR (DMSO-d6): 12.59 (1H, bs); 10.16 (1H,
(eluant cyclohexane/EtOAc 9:1Á8:2) obtaining com-
/
s); 10.06 (1H, s); 7.65 (2H, d); 7.38 (1H, d); 7.32 (2H, t);
7.29 (1H, dd); 7.08 (1H, d); 7.07 (1H, t); 6.08 (1H, t);
3.87 (1H, m); 3.65 (1H, dd); 3.47 (1H, m); IR (Nujol)
pound 24 as colourless solid (1.67 g, 65%): m.p. 83Á
/
1
85 8C; H NMR d (CDCl3): 7.84 (1H, d); 7.14 (2H, d);
7.05 (1H, dd); 6.82 (2H, d); 6.78 (1H, d); 5.57 (1H, d);
nmax. (cmꢁ1): 3242 (NH), 1747, 1676 and 1651 (CÄ
/
O);
H]ꢂ. Anal.
3.91 (1H, d); 3.79 (3H, s); 3.11 (1H, d); 2.94 (1H, d); 1.41
(9H, s); IR (Nujol) nmax. (cmꢁ1): 1728 and 1645 (CÄ
MS (FAB/Thiogly.): m/z 371 [Mꢂ
/
/
O);
H]ꢂ. Anal.
(C19H15ClN2O4) C, H, N.
MS (FAB/NBA): m/z
(C21H23ClINO4) C, H, N.
516 [Mꢂ
/
7.29. General procedure for the synthesis of the
compounds 28aÁ
7.26. (E)-2-[(5-Chloro-2-iodo-phenyl)-(4-methoxy-
benzyl)-carbamoyl]-5-phenylcarbamoyl-pent-4-enoic acid
tert-butyl ester (25)
/
c
To a suspension of compound 27 (1 equiv.) in MeCN
were added 1-hydroxybenzotriazole (1.2 equiv.) and 1-
[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydro-
chloride (1.5 equiv.) and the reaction mixture was stirred
for 1 h. The desired amine (1.5 equiv.) was added, the
reaction mixture was stirred for 2 h then extracted with
EtOAc. The organic layer was washed saturated
NaHCO3, brine, dried and evaporated under reduced
pressure. The crude residue was purified by flash
chromatography (eluant cyclohexane/EtOAc) or by
trituration to give the desired compounds.
To a solution of intermediate 24 (0.26 g, 0.50 mmol)
in THF (5 ml), cooled to ꢁ50 8C, was added a 1 M
/
solution of [(CH3)3Si]2NNa in THF (0.62 ml, 0.62
mmol). The reaction mixture was stirred at 0 8C for 1
h, then a solution of the bromocrotonate derivative
(0.12 g, 0.50 mmol) in THF (10 ml) was added dropwise.
The reaction mixture was stirred at 0 8C for 1 h then the
resulting solution was poured into brine and extracted
with EtOAc. The organic phase was dried, evaporated
and purified by flash column chromatography (eluant
cyclohexane/EtOAc 9:1Á
colourless solid (0.27 g, 80%): m.p. 63Á
/
7:3) affording compound 25 as
1
/
65 8C; H NMR
(acetone-d6): 9.19 (1H, bs); 8.05 (1H, d); 7.69 (2H, d);
7.28 (2H, t); 7.25 (1H, dd); 7.21 (2H, d); 7.03 (1H, t);
6.88 (4H, m); 6.14 (1H, d); 5.60 (1H, d); 3.92 (1H, d);
3.78 (3H, s); 3.07 (1H, t); 2.80 (2H, m); 1.38 (9H, s); IR
7.30. (E)-8-Chloro-2-oxo-5-phenylcarbamoylmethylene-
2,3,4,5-tetrahydro-1H-benzo[b]azepine-3-carboxylic
acid hydroxyamide (28a)
(Nujol) nmax. (cmꢁ1): 1700, 1670 and 1643 (CÄ
(FAB/NBA): m/z 675 [Mꢂ
H]ꢂ.
(C31H32ClIN2O5) C, H, N.
/
O); MS
Anal.
Compound 28a was prepared from 27 (0.13 g, 0.35
mmol) in MeCN (15 ml), then adding a solution of Et3N
(0.1 ml, 0.7 mmol) and O-(tert-butyldimethylsilyl)-
hydroxylamine in MeCN (5 ml), according to the
general procedure. Compound 28a was isolated by
trituration in CH2Cl2 as white solid (0.04 g, 30%). In
the mother liquor was recovered the O-silylated com-
pound (0.04 g), which can be deprotected using tetra-
butylammonium fluoride and AcOH to yield compound
28a (0.028 g, 90%): 1H NMR (DMSO-d6): 10.28 (1H, d);
10.12 (1H, s); 10.00 (1H, s); 8.86 (1H, d); 7.62 (2H, d);
7.38 (1H, d); 7.30 (2H, t); 7.07 (1H, d); 6.06 (1H, bs);
/
7.27. (E)-8-Chloro-1-(4-methoxy-benzyl)-2-oxo-5-
phenylcarbamoylmethylene-2,3,4,5-tetrahydro-1H-
benzo[b]azepine-3-carboxylic acid tert-butyl ester (26)
Compound 26 was prepared using the same methods
as compound 10a (refluxing for 2 h) and obtained as
1
white solid (0.77 g, 93%): m.p. 188Á
/
191 8C; H NMR
(DMSO-d6/70 8C): 9.86 (1H, bs); 7.63 (2H, d); 7.48 (1H,
bs); 7.35Á7.30 (1H, m); 7.31 (2H, t); 7.22 (1H, d); 7.05
(1H, t); 7.03 (2H, d); 6.75 (2H, d); 5.86 (1H, s); 5.09 (1H,
/
3.93 (1H, d); 3.5Á
/
3.3 (2H, m); MS (FAB/NBA): m/z 386
[Mꢂ
/
H]ꢂ. Anal. (C19H16ClN3O4) C, H, N.

R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á
/
738
735
7.31. (E)-8-Chloro-2-oxo-5-phenylcarbamoylmethylene-
2,3,4,5-tetrahydro-1H-benzo[b]azepine-3-carboxylic
acid amide (28b)
with EtOAc, washed with a 1 N solution of HCl and
brine, then dried and evaporated. The crude compound
was purified by flash column chromatography (eluant
cyclohexane/EtOAc 7:3) affording compound 28e as
1
Compound 28b was prepared from 27 (0.37 g, 1.0
mmol) in MeCN (40 ml), then adding [(CH3)3Si]2NH,
according to the general procedure. Compound 28b was
isolated by trituration in Et2O as white solid (0.17 g,
white solid (0.09 g, 60%): H NMR (DMSO-d6): 9.40
(1H, bs); 9.32 (1H, bs); 7.72 (2H, d); 7.46 (1H, d); 7.36Á
/
7.30 (3H, m); 7.23 (1H, d); 7.08 (1H, tt); 6.19 (1H, dd);
4.41 (1H, dd); 4.31 (1H, ddd); 3.79 (1H, ddd); IR (Nujol)
1
nmax. (cmꢁ1): 3196Á
Thiogly.): m/z 352 [Mꢂ
H, N.
/
3111 (NH); 1686 (CÄ
/
O); MS (FAB/
46%): m.p. decomp.; H NMR (DMSO-d6): 10.10 (1H,
/
H]ꢂ. Anal. (C19H14ClN3O2) C,
s); 9.96 (1H, s); 7.63 (2H, d); 7.38 (1H, d); 7.32 (1H, bs);
7.30 (2H, t); 7.28 (1H, dd); 7.05 (1H, d); 7.04 (1H, t);
6.94 (1H, bs); 6.05 (1H, s); 3.91 (1H, dd); 3.54 (1H, dd);
3.3 (1H, m); IR (Nujol) nmax. (cmꢁ1): 3200Á
NH2), 1690 and 1660 (CÄ
[Mꢂ
H]ꢂ. Anal. (C19H16ClN3O3) C, H, N.
/
3315 (NHꢂ
/
/
O); MS (FAB/NBA): m/z 370
7.35. (E)-8-Chloro-1-(4-methoxy-benzyl)-2-oxo-5-
phenylcarbamoylmethylene-2,3,4,5-tetrahydro-1H-
benzo[b]azepine-3-carboxylic acid (29)
/
7.32. (E)-8-Chloro-2-oxo-5-phenylcarbamoylmethylene-
2,3,4,5-tetrahydro-1H-benzo[b]azepine-3-carboxylic
acid phenylamide (28c)
A suspension of compound 26 (0.054 g, 0.1 mmol) in
formic acid (1 ml) was stirred for 1 h, then the acid was
evaporated and the crude material was triturated in
Compound 28c was prepared from 27 (0.03 g, 0.08
mmol) in MeCN (5 ml), then adding aniline, according
to the general procedure. Compound 28c was isolated
Et2O/petroleum (1.5/1.5 ml) to yield compound 29 as
1
white solid (0.04 g, 82%): m.p. 225Á
/
227 8C; H NMR
(acetone-d6): 11.50 (1H, bs); 9.20 (1H, bs); 7.74 (2H, d);
7.56 (1H, m); 7.32 (2H, m); 7.30 (1H, m); 7.24 (1H, d);
7.10 (2H, d); 7.08 (1H, t); 6.74 (2H, d); 5.83 (1H, s); 5.40
(1H, bm); 4.714 (1H, bm); 3.85 (1H, m); 3.40 (1H, m);
IR (Nujol) nmax. (cmꢁ1): 2730 (COOH), 1724 and 1643
by flash chromatography as white solid (0.018 g, 50%):
1
m.p. 229Á
/
230 8C; H NMR (DMSO-d6): 10.12 (1H, s);
10.08 (1H, s); 9.90 (1H, s); 7.63 (2H, dd); 7.53 (2H, dd);
7.41 (1H, d); 7.35Á7.25 (5H, m); 7.11 (1H, d); 7.06Á7.00
/
/
(2H, tt); 6.08 (1H, t); 4.07 (1H, ddd); 3.81 (1H, dd); 3.35
(1H, ddd); IR (Nujol) nmax. (cmꢁ1): 3319 (NH); 1691
(CÄ
/
O); MS (FAB/NBA): m/z 491 [Mꢂ
H]ꢂ. Anal.
(C27H23ClN2O5) C, H, N.
/
and 1678 (CÄ
/
O); MS (FAB/NBA): m/z 446 [Mꢂ
H]ꢂ.
/
Anal. (C25H20ClN3O3) C, H, N.
7.33. (E)-8-Chloro-2-oxo-5-phenylcarbamoylmethylene-
2,3,4,5-tetrahydro-1H-benzo[b]azepine-3-carboxylic
acid dimethylamide (28d)
7.36. (E)-2-[3-Benzenesulfonylaminocarbonyl-8-chloro-
1-(4-methoxy-benzyl)-2-oxo-1,2,3,4-tetrahydro-
benzo[b]azepin-5-ylidene]-N-phenyl-acetamide (30)
Compound 28d was prepared from 27 (0.13 g, 0.35
mmol) in MeCN (15 ml), then adding a 2 M solution of
(CH3)2NH in THF, according to the general procedure.
Compound 28d was isolated by trituration in Et2O as
white solid (0.1 g, 70%): H NMR (DMSO-d6): 10.14
(1H, s); 10.13 (1H, s); 7.64 (2H, d); 7.40 (1H, d); 7.30
To a solution of 29 (0.035 g, 0.07 mmol) in DMF (2
ml) was added carbonyldiimidazole (0.024 g, 0.15 mmol)
and the reaction mixture was stirred at 70 8C for 1 h.
The solution was cooled to 0 8C, then was added a
suspension of phenylsulphonylamine sodium salt in
DMF (prepared from phenylsulphonyl amine (0.036 g,
0.24 mmol) and NaH 80% (0.01 g, 0.24 mmol) in DMF
(2 ml)). The reaction mixture was stirred at r.t. for 4 h,
then EtOAc was added and the organic phase was
washed with 1 M solution of HCl and brine, dried and
evaporated. The crude product was purified by flash
column chromatography (eluant CH2Cl2/MeOH 9:1),
affording compound 30 as white solid (14 mg, 30%): 1H
NMR (DMSO-d6): 12.10 (1H, bs); 9.98 (1H, bs); 7.90
1
(3H, m); 7.11 (1H, d); 7.05 (1H, tt); 6.08 (1H, m); 4.04Á
3.93 (2H, m); 3.21 (1H, m); 2.81 (3H, s); 2.76 (3H, s); IR
(Nujol) nmax. (cmꢁ1): 3452, 3190 (NH), 1676 (CÄ
O); MS
(FAB/NBA): m/z 398 [Mꢂ
H]ꢂ. Anal. (C21H20ClN3O3)
C, H, N.
/
/
/
7.34. (E)-2-(8-Chloro-3-cyano-2-oxo-1,2,3,4-
tetrahydro-benzo[b]azepin-5-ylidene)-N-phenyl-
acetamide (28e)
(1H, bs); 7.8Á
/
7.5 (3H, m); 7.36Á7.26 (2H, m); 7.18 (1H,
/
m); 7.04 (1H, t); 6.98 (2H, bm); 6.70 (2H, m); 5.77 (1H,
s); 5.30 (1H, d); 4.62 (1H, d); 4.08 (1H, m); 3.60 (3H, s);
At 0 8C, trifluoroacetic anhydride (0.023 ml, 0.165
mmol) was added to a solution of compound 28b (0.055
g, 0.15 mmol) and Py (0.024 ml, 0.30 mmol) in THF (5
ml). The solution was stirred for 1 h at r.t., then diluted
2.94 (1H, m); MS (FAB/NBA): m/z 630 [Mꢂ
/
H]ꢂ.
Anal. (C33H28ClN3O6S) C, H, N.

736
R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á738
/
7.37. (E)-2-(3-Benzenesulfonylaminocarbonyl-8-chloro-
2-oxo-1,2,3,4-tetrahydro-benzo[b]azepin-5-ylidene)-N-
phenyl-acetamide (28f)
stirred 2 h at 0 8C, then diluted with brine and extracted
with EtOAc. The organic layer was dried and evapo-
rated. The crude compound was purified by flash
chromatography (cyclohexane/EtOAc 8:2) to obtain
1
Compound 28f was prepared using the same methods
as compound 11 and obtained as white solid (0.006 g,
1
63%): H NMR (acetone-d6): 10.96 (1H, bs); 9.33 (1H,
bs); 9.17 (1H, bs); 8.06 (2H, d); 7.73 (2H, m); 7.70 (1H,
compound 33 (0.17 g, 98%) as white foam: H NMR
(CDCl3) d 7.76 (d, 1H), 7.52Á
/
7.44 (m, 5H), 7.33Á7.3 (m,
/
4H), 7.22 (bs, 1H), 7.2Á7.1 (m, 3H), 6.95 (m, 1H), 6.82
/
(m, 2H), 6.74 (dd, 1H), 6.32 (d, 1H), 6.06 (m, 1H), 5.56
(d, 1H), 4.16 (dd, 1H), 3.95 (d, 1H), 3.79 (s, 3H), 3.20
m); 7.63 (2H, t); 7.44 (1H, d); 7.36Á7.29 (3H, m); 7.20
/
(1H, d); 7.08 (1H, m); 6.15 (1H, t); 4.16 (1H, m); 3.95
(1H, dd); 3.50 (1H, m); IR (Nujol) nmax. (cmꢁ1): 1668
(m, 1H). IR (Nujol) nmax. (cmꢁ1): 1686 and 1601 (CÄ
/
O);
H]ꢂ. Anal.
MS (FAB/NBA): m/z 679 [Mꢂ
/
and 1597 (CÄ
/
O); MS (FAB/NBA): m/z 510 [Mꢂ
H]ꢂ.
/
(C33H28ClIN2O4) C, H, N.
Anal. (C25H20ClN3O5S) C, H, N.
7.41. 2-[3-Benzoyl-8-chloro-1-(4-methoxy-phenyl)-2-
oxo-1,2,3,4,-tetrahydro-benzo[b]azepin-5-ylidene]-N-
phenyl-acetamide (34)
7.38. 2-Benzoyl-N-(5-chloro-2-iodo-phenyl)-N-(4-
methoxy-phenyl)-malonamic acid tert-butyl ester (31)
A solution of 24 (0.6 g, 1.2 mmol) in THF (25 ml) was
Compound 34 was prepared using the same methods
as compound 17, heating at 110 8C for 5 h and obtained,
after purification by flash column chromatography
cooled at ꢁ78 8C then [(CH3)3Si]2NNa 1 M in THF (1.8
/
ml, 1.8 mmol) was added and the reaction warmed to
0 8C. Benzoyl chloride (0.42 ml, 3.6 mmol) was added
and the reaction mixture stirred at r.t. for 15 min. The
solution was diluted with brine, extracted with EtOAc
and the organic layer was dried and evaporated. The
crude compound was purified by flash column chroma-
tography (cyclohexane/EtOAc 8:2) to obtain compound
31 (0.39 g, 52%) as yellow oil: 1H NMR (CDCl3) d 7.98
(d, 2H); 7.81 (d, 1H); 7.62 (t, 1H); 7.56 (d, 2H); 7.45 (t,
2H); 7.16 (d, 1H); 7.05 (d, 2H); 7.02 (dd, 1H); 5.59 (d,
1H), 4.19 (d, 1H); 3.79 (s, 1H); 3.72 (s, 3H); 1.03 (s, 9H);
(cyclohexane/EtOAc 7:3), as white foam (0.175 g,
1
70%): H NMR (CDCl3) d 10.05 (bs, 1H), 7.8Á
/7.5 (m,
8H), 7.4Á
/
7.25 (4H), 7.06 (t, 1H), 6.97 (d, 2H), 6.72 (d,
2H), 5.86 (s, 1H), 5.2 (m, 1H), 4.8 (m, 1H), 4.7 (m, 1H),
4.4 (m, 1H), 3.2 (m, 1H), 3.61 (s, 3H); MS (FAB/NBA):
m/z 551 [Mꢂ
H]ꢂ. Anal. (C33H27ClN2O4) C, H, N.
/
7.42. 2-(3-Benzoyl-8-chloro-2-oxo-1,2,3,4-tetrahydro-
benzo[b]azepin-5-ylidene)-N-phenyl-acetamide (35)
IR (Nujol) nmax. (cmꢁ1): 1734, 1703 and 1660 (CÄ
/
O);
H]ꢂ. Anal.
Compound 35 was prepared using the same methods
as compound 11, and obtained, after purification by
flash column chromatography (cyclohexane/EtOAc 6:4),
MS (FAB/NBA): m/z
(C28H27ClINO5) C, H, N.
620 [Mꢂ
/
1
as a white solid (0.011 g, 50%): H NMR (CDCl3) d
7.39. N-(5-Chloro-2-iodo-phenyl)-N-(4-methoxy-
phenyl)-3-oxo-3-phenyl-propionamide (32)
10.20 (bs, 1H), 10.14 (bs, 1H), 7.78 (d, 2H), 7.65 (d, 2H),
7.59 (t, 1H), 7.47 (t, 2H), 7.43 (d, 1H), 7.32 (t, 2H), 7.17
(d, 1H), 7.06 (t, 1H), 6.12 (bs, 1H), 4.79 (dd, 1H), 4.12
Compound 31 (0.39 g, 0.63 mmol) was dissolved in
CF3COOH (25 ml) and the solution was stirred for 30
min, then concentrated, diluted with EtOAc (30 ml) and
concentrated. The crude compound was purified by
flash chromatography (cyclohexane/EtOAc 8:2) to ob-
(m, 1H), 3.41 (m, 1H); MS (FAB/NBA): m/z 431 [Mꢂ
/
H]ꢂ. Anal. (C25H19ClN2O3) C, H, N.
1
Acknowledgements
tain compound 32 (0.31 g, 95%) as yellow oil: H NMR
(CDCl3) d 7.9Á
3.92 (d, 1H); 3.80 (s, 3H); 3.58 (d, 1H); IR (Nujol) nmax.
(cmꢁ1): 1691, 1661 and 1624 (CÄ
O); MS (FAB/NBA):
m/z 520 [Mꢂ
H]ꢂ. Anal. (C23H19ClINO3) C, H, N.
/
6.77 (m, 12H); 5.56 (d, 1H); 4.00 (d, 1H);
The authors thank the spectroscopy group for NMR
and IR spectra, Dr M. Hamdan’s group for mass
spectra data and Dr A. Garofalo for elemental analysis.
Thanks are due to Dr C. Pietra, S. Costa and E. Valerio
for the in vivo characterization in the NMDA-induced
convulsion model in mice and in the MCAo model in
rats.
/
/
7.40. 5-Benzoyl-hex-2-enedioic acid 6-[(5-chloro-2-iodo-
phenyl)-(4-methoxy-phenyl)-amide] 1-phenylamide (33)
To a solution of compound 32 (0.25 g, 0.48 mmol) in
THF, at ꢁ78 8C, [(CH3)3Si]2NK 0.5 M in toluene (1.3
/
ml, 0.67 mmol) was added and the solution was warmed
to 0 8C in 1 h. 4-Bromo-but-2-enoic acid phenylamide
(0.174 g, 0.72 mmol) was added and the reaction was
Appendix A

R. Di Fabio et al. / Il Farmaco 58 (2003) 723Á
/
738
737
Comp.
Theor. (%)
Found (%)
1
2
C 34.90; H 2.44; N 6.78
C 77.50; H 7.10
C 35.01; H 2.42; N 6.71
C 76.99; H 7.12
3
4
5
6
7
8
9
C 57.09; H 5.34; N 2.56
C 58.13; H 6.55; N 2.12
C 61.49; H 6.58; N 1.79
C 61.22; H 5.59; N 2.10
C 61.40; H 5.30; N 2.11
C 62.08; H 5.62; N 1.91
C 64.49; H 5.41; N 3.58
C 71.93; H 5.89; N 3.99
C 71.93; H 5.89; N 3.99
C 63.07; H 4.41; N 8.17
C 51.48; H 4.01; N 4.29
C 58.13; H 4.70; N 5.02
C 55.78; H 4.32; N 5.00
C 58.41; H 5.21; N 4.26
C 60.32; H 4.62; N 6.21
C 68.51; H 5.07; N 7.05
C 54.35; H 4.32; N 10.01
C 48.16; H 3.19; N 8.87
C 45.01; H 3.51; N 3.75
C 45.64; H 3.62; N 2.96
C 44.42; H 3.29; N 3.05
C 48.90; H 4.49; N 2.72
C 55.16; H 4.78; N 4.15
C 68.06; H 5.71; N 5.12
C 61.55; H 4.08; N 7.55
C 59.15; H 4.18; N 10.89
C 61.71; H 4.36; N 11.36
C 67.34; H 4.52; N 9.42
C 63.40; H 5.07; N 10.56
C 64.87; H 4.01; N 11.94
C 66.06; H 4.72; N 5.71
C 62.90; H 4.48; N 6.67
C 58.88; H 3.95; N 8.24
C 54.25; H 4.39; N 2.26
C 53.15; H 3.68; N 2.69
C 58.38; H 4.16; N 4.13
C 71.93; H 4.94; N 5.08
C 69.69; H 4.44; N 6.50
C 57.11; H 5.33; N 2.58
C 58.10; H 6.52; N 2.14
C 61.52; H 6.60; N 1.78
C 61.21; H 5.57; N 2.07
C 61.44; H 5.29; N 2.13
C 62.00; H 5.58; N 1.88
C 64.39; H 5.43; N 3.62
C 71.85; H 5.87; N 4.02
C 72.00; H 5.92; N 3.93
C 63.10; H 4.38; N 8.16
C 51.50; H 4.00; N 4.29
C 58.08; H 4.76; N 5.05
C 55.83; H 4.30; N 4.96
C 58.53; H 5.19; N 4.29
C 60.40; H 4.61; N 6.23
C 68.48; H 5.05; N 7.09
C 54.31; H 4.29; N 9.98
C 48.18; H 3.17; N 8.91
C 44.98; H 3.54; N 3.77
C 45.68; H 3.60; N 3.00
C 44.44; H 3.29; N 3.03
C 48.95; H 4.51; N 2.71
C 55.19; H 4.80; N 4.12
C 68.11; H 5.77; N 5.10
C 61.57; H 4.09; N 7.53
C 59.19; H 4.20; N 10.83
C 61.76; H 4.33; N 11.41
C 67.37; H 4.50; N 9.39
C 63.41; H 5.06; N 10.53
C 64.91; H 3.99; N 11.98
C 66.01; H 4.68; N 5.67
C 62.96; H 4.52; N 6.65
C 58.94; H 3.92; N 8.19
C 54.19; H 4.41; N 2.29
C 53.10; H 3.69; N 2.74
C 58.33; H 4.15; N 4.11
C 72.12; H 4.99; N 4.97
C 69.91; H 4.48; N 6.54
10a
10b
11
12
13
14
15
16
17
19a
19b
21
22
23
24
25
26
27
28a
28b
28c
28d
28e
29
30
28f
31
32
33
34
35
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