Optimized N-phenyl-N′-(2-chloroethyl)ureas as potential antineoplastic agents: Synthesis and growth inhibition activity

Article abstract of DOI:10.1016/j.bmc.2005.07.048

In our ongoing research program aimed at the optimization of microtubule-self-assembly disrupting agents, we have prepared three series of phenylurea analogues (CEU), derived from N-(3-ω-hydroxyalkyl or 4-ω-hydroxyalkyl or 3-ω-hydroxyalkynyl)-phenyl-N′-(2

Full text of DOI:10.1016/j.bmc.2005.07.048

Bioorganic & Medicinal Chemistry 13 (2005) 6703–6712
Optimized N-phenyl-N0-(2-chloroethyl)ureas as
potential antineoplastic agents: Synthesis and
growth inhibition activity
a,ꢀ
Emmanuel Moreau,a, ,ꢀ Sebastien Fortin, Michel Desjardins,b,ꢁ Jean L. C. Rousseau,b
*
´
Eric Petitclerc and Rene C.-Gaudreault
a
a,
*
´
´
a
´ ´ ˆ
Unite de biotechnologie et de bioingenierie, 10, rue de L’Espinay, C.H.U.Q., Hopital Saint-Franc¸ois d’Assise,
´
´
Universite Laval, Quebec, QC, Canada G1L 3L5
ˆ ´
IMOTEP inc., 86, Cote-de-la-Montagne, suite #3, Quebec, QC, Canada G1K 4E3
b
Received 4 October 2004; accepted 20 July 2005
Available online 13 September 2005
Abstract—In our ongoing research program aimed at the optimization of microtubule-self-assembly disrupting agents, we have pre-
pared three series of phenylurea analogues (CEU), derived from N-(3-x-hydroxyalkyl or 4-x-hydroxyalkyl or 3-x-hydroxyalkynyl)-
phenyl-N0-(2-chloroethyl)ureas. Most compounds exhibit potent growth inhibitory activity on human colon carcinoma HT-29,
human skin melanoma M21, and human breast carcinoma MCF-7 tumor cell lines, with a GI50 ranging from 250 nM to 8 lM.
Among these new molecules, three CEUs exhibit GI50 in the nanomolar range. They are more potent by approximately an order
of magnitude than previously described CEU analogues. As such, they are attractive hit compounds for the development of potent
new alkylating antitubulin drugs.
ꢀ 2005 Elsevier Ltd. All rights reserved.
1. Introduction
anticancer agents developed in the past decades, mole-
cules acting on the cellular microtubule dynamics form
one of the largest group of effective chemotherapeutics.
Cancers are a group of malignant diseases responsible
for tremendous health costs associated with high level
of mortality and morbidity. As a result, numerous che-
motherapeutic agents have been developed to impede
the progression of malignant tumors or prevent their
recurrence. Chemotherapeutic treatments are largely
palliative and are useful for limited periods of time.1
Chemotherapeutic agents often fail when drug resistant
tumor cells become predominant, when the dose-related
toxicity is too high to obtain optimal anticancer activity
or when side effects are simply unbearable. Amongst the
Microtubules are heterodimers composed of a- and b-
tubulin isoforms. Microtubulesꢂ assembly forms cyto-
skeleton components, present in all eukaryotic cells.2
During mitosis, microtubules are highly dynamic and
are constantly reshaping in fast polymerization–depoly-
merization processes. When natural or synthetic ligands
interact with microtubule dynamics, they disrupt the
cytoskeleton and block mitosis into the G2/M phase.
Cells then initiate an apoptotic program. Tubulin cellu-
lar importance still makes it an attractive target for the
development of potent anticancer drugs.3
Keywords: Aryl chloroethylureas; Antitubulin agents; Antimicrotubule
agents; Alkylating agents; Anticancer drugs; Colchicine-binding site
agents.
Antitubulin agents4 bind to tubulin according to four
different modes.5 In the first mode, drugs bind preferen-
tially to polymerized tubulin. It includes the well-known
paclitaxel and other members, such as epothilone B, dis-
codermolide, and dyctyostatin.4,5 For the three other
modes, agents either form a covalent link to tubulin cys-
teine residues, bind to the colchicine site, or bind in the
vinca domain. Vinblastine, vincristine, and peptides,
*
Corresponding authors. Tel.: +1 418 525 4444x52363; fax: +1 418 525
4372 (R.C.G.); tel.: +33 47 317 80 00; fax: +33 47 317 80 12 (E.M.);
e-mail addresses: moreaumanu@yahoo.fr; rene.c-gaudreault@crsfa.
ulaval.ca
ꢀ
ꢁ
These authors contributed equally to this work.
Present address: OmegaChem inc., 8800, Boulevard de la Rive-Sud,
Le´vis, QC, Canada G6V 9H1.
0968-0896/$ - see front matter ꢀ 2005 Elsevier Ltd. All rights reserved.
doi:10.1016/j.bmc.2005.07.048

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E. Moreau et al. / Bioorg. Med. Chem. 13 (2005) 6703–6712
such as dolastatins and hemiasterlins, are agents acting
on the vinca domain.4,5 Colchicine,6 combretastatin,7
and podophyllotoxins8 interact with the colchicine-bind-
ing site. The site is located on b-tubulin at the interface
between a- and b-tubulins, close to the T7 loop and the
H8 helix.9 Ligand interactions with the colchicine-bind-
ing site are mainly electrostatic in nature (docking) and
thus reversible for most compounds. N-Phenyl-N0-(2-
chloroethyl)ureas (CEUs)10 form a covalent link with
cysteine residue within the colchicine-binding site. Orig-
inally developed by our laboratory, CEUs react specifi-
cally with a few proteins, including b-tubulin.10 We
demonstrated that CEUs substituted at the 4-position
of the phenyl ring by hydrophobic moieties are potent
tumor cell growth inhibitors. They act as angiogenesis
inhibitors both in vitro and in vivo.11 They also inhibit
tumor cell growth in vivo on the murine colon
carcinoma CT-26 model.12 Interestingly, some CEU
derivatives have been shown to be orally bioavailable.13
The antimicrotubule activity of many CEUs is based
on the alkylation of an amino acid within the colchi-
cine-binding site. We showed that CEU-022, that is,
N-[4-(1,1-dimethylethyl)-phenyl]-N0-(2-chloroethyl) urea,
alkylates specifically the cysteine 239 residue of b-tubu-
lin.10 b-Tubulin alkylation by CEUs can be detected in
an electrophoretic shift assay.14
macokinetics and metabolism studies. We describe here
the synthesis and growth inhibition activity of three
different series of derivatives designed as N-(3-x-
hydroxyalkyl or 4-x-hydroxyalkyl or 3-x-hydroxyalky-
nyl)phenyl-N0-(2-chloroethyl)ureas.
2. Results and discussion
2.1. Synthesis of N-phenyl-N0-(2-chloroethyl)ureas
(CEUs)
2.1.1. Synthesis of 3-substituted derivatives. Schemes 1
and 2 depict the synthetic procedure used for the prepa-
ration of N-(3-x-hydroxyalkylphenyl)-N0-(2-chloroeth-
yl)ureas. The preparation of CEUs 1a to n was
straightforward, which involved the nucleophilic addi-
tion of 3-hydroxyaniline and aniline derivatives 215
and 316 to 2-chloroethylisocyanate.
Therefore, commercially available 3-hydroxyaniline was
converted into the corresponding N-(hydroxyphenyl)-
N0-(2-chloroethyl)urea (1a). Compounds 1b and c were
also obtained by direct addition of the respective ani-
lines 2 and 3 to 2-chloroethylisocyanate in dry dichloro-
methane. Anilines 2 and 3 were obtained through the
reduction of the nitro group of commercially available
3-nitrobenzylalcohol and 2-(3-nitrophenyl)-1-ethanol
using metallic reduction with SnCl2Æ2H2O in ethanol.
In the context of pharmacomodulating the properties of
N-phenyl-N0-(2-chloroethyl)ureas, we prepared mole-
cules with phenyl ring substituents bearing terminal
functional group that are more hydrophilic to alter the
moleculeꢂs biodistribution and toxicity in animal phar-
Scheme 2 describes the approach used to introduce long-
er hydroxyalkyl chains in compounds 1d–k. We under-
OH
OH
i
HN
O
H N
2
NH
CH CH Cl
2
2
1a
CH OH
2
CH OH
2
CH OH
2
i
ii
HN
O N
2
H N
2
NH
2
O
CH CH Cl
2
2
1b
CH CH OH
2
2
CH CH OH
CH CH OH
ii
i
2
2
2
2
HN
O N
2
H N
2
NH
3
O
CH CH Cl
2
2
1c
Scheme 1. Reagents: (i) 2-chloroethylisocyanate, CH2Cl2; (ii) SnCl2Æ2H2O, EtOH.

E. Moreau et al. / Bioorg. Med. Chem. 13 (2005) 6703–6712
6705
I
O2N
i
(CH2)nOH
n = 1 to 5
4d-h
O2N
ii
iv
(CH2)nOH
(CH2)nOH
5d-h
H2N
6d-f
iii
H2N
iii
(CH2)nOH
(CH2)nOH
HN
O
HN
O
NH
CH2CH2Cl
1i-k
NH
CH2CH2Cl
1d-h
Scheme 2. Reagents: (i) alkyne, CuI, K2CO3, PPh3, Pd/C, DME/H2O; (ii) H2, Pd/C, EtOH; (iii) 2-chloroethylisocyanate, CH2Cl2; (iv) Fe/HCl, EtOH/
H2O.
took a Sonogashira-like17,18 addition with propargyl
alcohol, 3-butyn-1-ol, 4-pentyn-1-ol, 5-hexyn-1-ol19 or
6-heptyn-1-ol, mixed with 1-iodo-3-nitrobenzene (8),
using Pd(0)/PPh3 as catalyst. The reactions proceeded
smoothly to afford the corresponding x-hydroxyalkynyl
derivatives 4d–h20 in yields ranging from 43% to 88%.
Compounds 4d–h20 were then converted into the corre-
sponding anilino-x-hydroxyalkyl derivatives 5d–h21 by
hydrogenation in ethanol using palladium on carbon
as catalyst. Compounds 5d–h21 were obtained in yields
ranging from 80% to 100%. Afterwards, the latter prod-
ucts were converted into their corresponding 2-chloro-
ethylureas 1d–h by addition of 2-chloroethylisocyanate
to anilines 5d–h21 in dry dichloromethane with 28% to
51% urea yields.
alkyne produced 7d–f with 32%–73% yields. Catalytic
hydrogenation of 7d–f using palladium on carbon, fol-
lowed by condensation of the aniline 8d–f with 2-chlo-
roethylisocyanate, gave 1l–n in good yields (36–96%).
2.2. Growth inhibition activity
The growth inhibition assays22 were conducted twice in
triplicate on three human tumor cell lines of different tis-
sue origin. The tumor cell lines used were HT-29 (human
colon carcinoma), M21 (human skin melanoma), and
MCF-7 (human breast carcinoma), respectively. Growth
inhibition activity is expressed in terms of GI50 value
(lM), which is the drug concentration required to inhib-
it tumor cell growth by 50%.
Compounds 6d–f were prepared by chemoselective
reduction of the aromatic nitro group of compounds
4d–f by catalytic reduction using iron in a mixture of
concentrated hydrochloric acid and ethanol to obtain
6d–f in fair to good yields. Finally, compounds 6d–f
were converted into 1i to 1k by addition of 2-chloroethy-
lisocyanate with 51% to 63% yields.
Table 1 summarizes the ability of 1a–h to inhibit tumor
cell growth. After two days of treatment, the GI50 value
was determined using the NIH sulforhodamine assay.
Compounds 1a–c bearing short saturated x-hydroxy-
alkyl side chains (n < 3) were inactive at the concentra-
tions tested. Interestingly, compounds 1d–h bearing
longer x-hydroxyalkyl side chains had a significant
impact on growth inhibition activity in all tumor cells
tested as the side chain increased, reaching the best
GI50 value at five carbon atoms.
2.1.2. Synthesis of 4-substituted CEUs. Scheme 3 shows
the preparation of 4-substituted CEUs 1l–n. The last
series of compounds was prepared using conditions
similar to those described previously for compounds
1d–f. Starting from 4-iodoaniline, introduction of the
The growth inhibition potency of compounds 1d–f
inspired us to prepare compounds 1l–n, substituted in

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E. Moreau et al. / Bioorg. Med. Chem. 13 (2005) 6703–6712
Table 2. Growth inhibition activity of compounds (1l–m) on three
different human cancer cell lines
H2N
I
i
Compound
n
GI50 (lM)
(CH2) nOH
H2N
HT-29
M21
MCF-7
7d-f
ii
1l
3
4
5
>10
>10
>10
>10
>10
>10
>10
>10
>10
n = 1 to 3
1m
1n
(CH2)nOH
The impact of substituents in position 3 was evaluated
further by increasing the rigidity of the x-hydroxyalkyl
side chain with the introduction of a triple bond. It
seems to abrogate the growth inhibition activity (see
Table 4).
H2N
8d-f
iii
We are contemplating two hypotheses to explain the in-
crease in cell growth inhibition activity due to: (i) the
three isomeric form, (ii) less rigid forms of potent
CEU, and (iii) the effect of x-hydroxyalkyl side chains
in position 3 as opposed to position 4. The first hypoth-
esis is based on a model of colchicine interactions—that
we are developing—to its own b-tubulin binding site
where a hydrogen or p-bond interaction could take
place between an oxygen atom on the colchicine C ring
and a key amino acid in tubulin.24 In that context and
based on previous alkylation results of b-tubulin by a
CEU moiety,10 CEUs substituted in position 3 with 4-
to 7-carbon atom x-hydroxyalkyl groups might be able
to interact similarly to colchicine by generating either a
hydrogen bond or a p-bond with amino acids located
into the colchicine-binding site. The oxygen atom on
the x-hydroxyalkyl chain would stabilize, the molecules
in a proper spatial configuration favoring the alkylation
of cysteine 239 residue by the chloroethylurea moiety of
the molecule. Such a configuration seems to be unfavor-
able for the 4-isomers composed of hydroxyalkenyl
homologues and 3-isomers hydroxyalkyl chains shorter
than four carbon atoms. A second hypothesis points
toward an intrinsic role of the five-carbon chain in
position 3 and nature of the end-chain substituent. To
explore this possibility, several CEU compounds are
being synthesized to evaluate the relative impact
of chain length and end-chain functional groups. Struc-
ture–activity relationships will determine if the five-car-
bon chain with a terminal hydroxyl group is the cause of
an increase in potency and optimal combination.
(CH2)nOH
H
N
H
N
ClH2CH2C
O
1l-n
Scheme 3. Reagents: (i) alkyne, CuI, K2CO3, PPh3, Pd/C, DME/H2O;
(ii) H2, Pd/C, EtOH; (iii) 2-chloroethylisocyanate, CH2Cl2.
position 4 of the aromatic ring, instead of position 3
with identical hydroxyalkyl chains (see Table 2). There
was no impact on growth inhibition activity by com-
pounds 1l–n at the concentration tested, as opposed to
compounds 1d–f. However, CEUs substituted by alkyl
moieties in 4-position or an iodine atom (see Table
3)23 demonstrated a much better growth inhibition
activity. The switch from 4- to 3-position with hydrox-
yalkyl chains generated CEU compounds 1d–f with a
growth inhibition activity improved by an order of mag-
nitude compared to the previous CEUs with the best
growth inhibition activity (see Table 3).
Table 1. Growth inhibition activity of compounds (1a–h) on three
different human cancer cell lines
Compound
n
GI50 (lM)
3. Conclusion
HT-29
M21
MCF-7
In summary, compounds 1f–h appear to be essentially
equivalent with GI50 in the nanomolar range if we con-
sider structure–activity relationships. These three CEUs
are approximately 1 order of magnitude more potent
than all hydrophobic CEUs tested so far (see Table 3).
These findings demonstrate that the growth inhibition
activities of N-(3-x-hydroxyalkyl, 4-x-hydroxyalkyl,
and 3-x-hydroxyalkynyl)phenyl-N0-(2-chloroethyl)urea
1a
1b
1c
1d
1e
1f
0
1
2
3
4
5
6
7
>10
>10
>10
5.2
>10
>10
>10
6.0
>10
>10
>10
7.9
1.1
1.7
2.5
0.25
0.47
0.53
0.39
0.52
0.54
0.49
0.55
0.58
1g
1h

E. Moreau et al. / Bioorg. Med. Chem. 13 (2005) 6703–6712
6707
23
Table 3. Previously synthesized compounds with the best growth inhibition activity
Compound Names
GI50 (lM)
HT-29 MCF-7
CEU-071
N-4-(1-Methylpropyl)phenyl-N0-(2-chloroethyl)urea
1.8
1.9
2.3
1.0
1.3
5.2
4.8
4.7
2.9
3.2
CEU-087(R) N-4-(1-Methylpropyl)phenyl-N0-[(1R)-2-chloro-1-methylethyl]urea
CEU-070
N-4-(1-Methylethyl)phenyl-N0-(2-chloroethyl)urea
CEU-085(R) N-4-(1-Methylethyl)phenyl-N0-[(1R)-2-chloro-1-methylethyl]urea
CEU-107(R) N-(4-Iodophenyl)-N0-[(1R)-2-chloro-1-methylethyl]urea
Table 4. Growth inhibition activity of compounds (1i–k) on three
different human cancer cell lines
in fresh medium and aliquots of 100 lL containing
sequential dilution of drugs were added. Final drug con-
centrations ranged from 100 to 0.3 lM. DMSO concen-
tration was maintained lower than 0.5% so to avoid
solvent’s cytotoxicity. Plates were incubated for 48 h.
Assays were stopped by addition of cold trichloroacetic
acid to the wells (final concentration being 10%), fol-
lowed by incubation for 60 min at 4 ꢁC. Plates were
washed five times with tap water. Sulforhodamine B
solution (50 lL) at 0.1 % (w/v) in 1% acetic acid was
added to each well, and plates were incubated for
15 min at room temperature. After staining, unbound
dye was removed by washing five times with 1% acetic
acid. Bound stain was solubilized with 10 mM Tris base,
and the absorbance was read using a lQuant Universal
Microplate Spectrophotometer (Biotek, Winooski, VT)
at 585 nm. The results were compared with those of a
control reference plate fixed on the treatment day and
the growth inhibition percentage was calculated for each
drug contact period. The experiments were performed at
least twice in triplicate. The GI50 assay was considered
valid when the variability among data for a given set
of conditions, within the same experiment, was less than
10% with respect to the mean value. For that reason,
data are reported with two significant figures.
Compound
n
GI50 (lM)
HT-29
M21
MCF-7
1i
1
2
3
>10
>10
>10
>10
>10
>10
>10
>10
>10
1j
1k
series are not equivalent. Growth inhibition by CEUs
tested here requires substitution in position 3, a chain
length clearly defined between 4 and 7 carbon atoms,
without the rigidity induced by a triple bond, and a ter-
minal hydroxyl group. The ability of these compounds
to alkylate b-tubulin is currently under way. It will then
be possible to determine if the degree of b-tubulin alkyl-
ation and growth inhibition values are related. CEUs’
computer modelization within the recently available
cocrystallized colchicine-a- and b-tubulin coordinates27
will be used to test the stabilizing effect of 3-x-hydrox-
yalkyl substituents.
4.2. Experimental procedures
4.2.1. Chemistry and chemical methods. Proton NMR
spectra were recorded on a Bruker AM-300 spectrome-
ter (Bruker, Germany). Chemical shifts (d) are reported
in parts per million, relative to the internal tetrameth-
ylsilane standard. IR spectra were recorded on a Uni-
cam spectrometer. Uncorrected melting points were
determined on an electrothermal melting point appara-
tus. All reactions were conducted under a dried nitrogen
atmosphere. Chemicals were supplied by Aldrich Chem-
ical (Milwaukee, WI). Liquid flash chromatography was
performed on silica gel 60 A (American Chemicals Ltd.,
Montreal, Canada), using the indicated solvent mixture
4. Experimental
4.1. Cell growth inhibition assay
The growth inhibition potency of CEUs was assessed
using the procedure described by the National Cancer
Institute for its drug screening program.22 Ninety-six
well tissue culture plates were seeded with 100 lL tumor
cell lines suspended in high glucose DMEM supplement-
ed with 5% (v/v) defined bovine calf serum iron
(Hyclone). Plates were incubated at 37 ꢁC, 5% CO2 for
24 h. Freshly solubilized drugs in DMSO were diluted

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E. Moreau et al. / Bioorg. Med. Chem. 13 (2005) 6703–6712
expressed as volume/volume ratios. Solvents and re-
agents were used without purification unless specified
otherwise. The progress of all reactions was monitored
using TLC on precoated silica gel plates (Merck Silica
Gel 60 F254). The chromatograms were viewed under
UV light at 254 nm. For column chromatography,
Merck Silica Gel (70–230 mesh) was used.
CH2); 13C NMR (CDCl3) d: 146.6, 139.8, 129.5, 119.3,
115.9, 113.4, 63.5, 39.2.
4.3.3. 3-(3-Aminophenyl)-2-propyn-1-ol (6d). Compound
6d was synthesized from 4d using general method B.
The crude product was purified by flash chromatogra-
phy (silica gel, hexanes/ethyl acetate 4:6). Yield 75%;
IR (NaCl) m: 3375 (OH, NH), 2229 (C„C), 1287 (C–
1
4.3. General preparation of compounds 2, 3, 5d–h, 6d–f,
and 8d–f
O) cmꢀ1; H NMR (CDCl3) d: 7.08 (t, 1H, J = 7.9 Hz,
Ar), 6.83 (d, 1H, J = 7.7 Hz, Ar), 6.75 (s, 1H, Ar),
6.64 (d, 1H, J = 8.0 Hz, Ar), 4.46 (s, 2H, CH2); 13C
NMR (CDCl3): 146.2, 19.3, 122.1, 118.0, 115.6, 86.7,
85.9, 51.6.
Method A: The 3-nitro group of 3-nitrobenzylalcohol or
2-(3-nitrophenyl)-1-ethanol (1.00 mmol) was reduced by
catalytic reduction using SnCl2Æ2H2O (6 mmol) in ethyl
alcohol (10 mL) and refluxed for 6 h. After cooling
and evaporation of the solvent, the residue was taken
up in 1 N NaOH (20 mL) and extracted with ether
(3 · 15 mL). The combined organic extracts were
washed with brine and dried (Na2SO4). Evaporation of
the solvent and purification of the residue by flash chro-
matography on silica gel provided anilines 2 or 3.
4.3.4. 4-(3-Aminophenyl)-3-butyn-1-ol (6e). Compound
6e was synthesized from 4e using general method B.
The crude product was purified by flash chromatogra-
phy (silica gel, hexane/ethyl acetate 6:4). Yield 49%;
IR (NaCl) m: 3348 (OH, NH), 2228 (C„C), 1285 (C–
1
O) cmꢀ1; H NMR (CDCl3) d: 7.03 (t, 1H, J = 7.9 Hz,
Ar), 6.80 (d, 1H, J = 7.5 Hz, Ar), 6.70 (s, 1H, Ar),
6.57 (d, 1H, J = 8.0 Hz, Ar), 3.73 (t, 2H, J = 6.4 Hz,
CH2), 3.45 (br s, 2H, NH2), 2.60 (t, 2H, J = 6.4 Hz,
CH2); 13C NMR (CDCl3) d: 146.3, 129.3, 124.1, 122.1,
118.2, 115.2, 86.2, 82.4, 61.1, 23.7.
Method B: The appropriate nitro compound 4d–f
(1.00 mmol) was dissolved in a mixture (10:1) of ethanol
and water (22 mL). Powdered iron (7.28 mmol) and five
drops of concentrated hydrochloric acid were added.
The mixture was refluxed for 4 h. After cooling, the mix-
ture was evaporated to dryness. A saturated solution of
Na2CO3 (20 mL) was added, and the mixture was
extracted with dichloromethane (3 · 15 mL). The organ-
ic portions were pooled, dried over Na2SO4, and con-
centrated under reduced pressure. The solid residue
was then purified by flash chromatography on silica
gel to afford 6d–f.
4.3.5. 5-(3-Aminophenyl)-4-pentyn-1-ol (6f). Compound
6f was synthesized from 4f using general method B.
The crude product was purified by flash chromatogra-
phy (silica gel, hexane/ethyl acetate 6:4). Yield 75%;
IR (NaCl) m: 3354 (OH, NH), 2232 (C„C), 1289 (C–
1
O) cmꢀ1; H NMR (CDCl3) d: 7.03 (t, 1H, J = 7.7 Hz,
Ar), 6.77 (d, 1H, J = 7.7 Hz, Ar), 6.69 (s, 1H, Ar),
6.57 (d, 1H, J = 7.7 Hz, Ar), 3.76 (t, 2H, J = 6.0 Hz,
CH2), 3.25 (br s, 2H, NH2), 2.47 (t, 2H, J = 6.0 Hz,
CH2), 1.81 (t, 2H, J = 6.0 Hz, CH2); 13C NMR (CDCl3)
d: 146.3, 129.2, 124.4, 122.0, 118.0, 114.9, 88.9, 81.3,
61.6, 31.4, 16.0.
Method C: A mixture of the appropriate alkenyl deriva-
tives 4d–h or 7d–f (0.43 mmol), Pd/C 10% in ethanol
(30 mL) was reduced under hydrogen atmosphere
(38 psi) overnight. The catalyst was removed by filtra-
tion on Celite and the filtrate was evaporated to dryness.
The residue was purified by flash chromatography on
silica gel to afford 5d–h or 8d–f.
4.3.6. 3-(3-Aminophenyl)-1-propanol (5d).21c Compound
5d was synthesized from 4d using general method C. The
crude product was purified by flash chromatography
(silica gel, ether/hexanes 90:10). Yield 85%; IR (NaCl)
1
4.3.1. 3-Aminobenzyl alcohol (2).15 Compound 2 was
synthesized from 3-nitrobenzylalcohol using general
method A. The crude product was purified by flash
chromatography (silica gel, dichloromethane/methanol
98:2). Yield 100%; mp 89–92 ꢁC; IR (KBr) m: 3364
(OH), 2913 (NH), 1030 (C–O) cmꢀ1; 1H NMR (CDCl3)
d: 7.15 (m, Ar, 1H), 6.74 (m, Ar, 2H), 6.62 (m, Ar, 1H),
4.60 (s, CH2, 2H), 2.90 (br s, OH, NH2, 3H); 13C NMR
(CDCl3) d: 146.7, 139.9, 129.5, 117.1, 114.4, 113.6, 65.4.
m: 3351 (OH), 2927 (NH), 1057 (C–O) cmꢀ1. H NMR
(CDCl3) d: 7.08 (t, 1H, J = 7.5 Hz, Ar), 6.61 (d, 1H,
J = 7.0 Hz, Ar), 6.52 (s, 2H, Ar), 3.62 (t, 2H,
J = 7.0 Hz, CH2), 3.29 (br s, 2H, NH2), 2.59 (t, 2H,
J = 7.0 Hz, CH2), 1.84 (t, 2H, J = 7.0 Hz, CH2); 13C
NMR (CDCl3) d: 147.8, 131.3, 129.3, 118.8, 115.3,
112.8, 62.4, 34.1, 32.1.
4.3.7. 4-(3-Aminophenyl)-1-butanol (5e).21a Compound
5e was synthesized from 4e using general method C.
The crude product was purified by flash chromatogra-
phy (silica gel, dichloromethane/methanol 95:5). Yield
100%; IR (NaCl) m: 3363 (OH), 2934 (NH), 1167 (C–
4.3.2. 2-(3-Aminophenyl)-1-ethanol (3).16 Compound 3
was synthesized from 2-(3-nitrophenyl)-1-ethanol using
general method A. The crude product was purified by
flash chromatography (silica gel, dichloromethane/
methanol 98:2). Yield 49%; mp 51–53 ꢁC; IR (KBr) m:
1
O) cmꢀ1; H NMR (CDCl3) d: 7.06 (m, 1H, Ar), 6.59
(d, 1H, J = 7.5 Hz, Ar), 6.50 (m, 2H, Ar), 3.59 (t, 2H,
J = 6.0 Hz, CH2), 3.17 (s, 2H, NH2), 2.53 (t, 2H,
J = 7.5 Hz, CH2), 1.62 (m, 4H, CH2); 13C NMR
(CDCl3); d: 146.4, 143.7, 129.2, 118.9, 115.4, 112.8,
62.6, 35.6, 32.3, 27.4.
1
3303 (OH), 2917 (NH), 1057 (C–O) cmꢀ1; H NMR
(CDCl3) d: 7.10 (m, Ar, 1H), 6.62 (d, Ar, 1H,
J = 7.5 Hz), 6.55 (m, Ar, 2H), 3.81 (t, 2H, J = 7.3 Hz,
CH2), 3.04 (s, OH, NH2, 3H), 2.76 (t, 2H, J = 7.3 Hz,

E. Moreau et al. / Bioorg. Med. Chem. 13 (2005) 6703–6712
6709
4.3.8. 5-(3-Aminophenyl)-1-pentanol (5f). Compound 5f
was synthesized from 4f using general method C. The
crude product was purified by flash chromatography
(silica gel, hexanes/ethyl acetate 70:30). Yield 85%; IR
s, 2H, NH2), 2.51 (t, 2H, J = 6.5 Hz, CH2), 1.58 (m,
4H, CH2), 1.38 (t, 2H, J = 6.5 Hz, CH2); 13C NMR
(CDCl3) d: 143.9, 132.9, 128.9, 115.3, 62.9, 35.0, 32.7,
31.6, 25.4.
(NaCl) m: 3357 (OH), 2934 (NH), 1167 (C–O) cmꢀ1
;
1H NMR (CDCl3) d: 7.07 (m, 1H, Ar), 6.60 (d, 1H,
J = 7.5 Hz, Ar), 6.52 (m, 2H, Ar), 3.59 (t, 2H,
J = 7.0 Hz, CH2), 3.23 (s, 3H, NH2OH), 2.53 (t, 2H,
J = 7.0 Hz, CH2), 1.57 (m, 4H, 2 · CH2), 1.38 (m, 2H,
CH2); 13C NMR (CDCl3) d: 146.3, 143.9, 129.2, 118.9,
115.5, 112.8, 62.7, 35.9, 32.6, 31.1, 25.5.
4.4. Typical synthesis procedure for the preparation of
compounds 4d–h and 7d–f
To a mixture of the appropriate iodinated compound (3-
iodonitrobenzene or 4-iodoaniline) (4.56 mmol), K2CO3
(1.57 g, 11.4 mmol) in a mixture of 1,2-DME/water
(1:1; 30 mL) were successively added CuI (34 mg,
0.18 mmol), PPh3 (95.80 mg, 0.36 mmol), and Pd/C
10% (97.05 mg, 0.09 mmol). The mixture was stirred at
room temperature for 1 h. Afterwards, the x-hydrox-
yalkenyl derivative (14.40 mmol) was added, and the
mixture was refluxed overnight. After cooling, the mix-
ture was filtered on Celite and the solvent was evaporat-
ed under reduced pressure. An aqueous solution of 1 N
HCl (20 mL) was then added to the residue and extract-
ed with ethyl acetate (3 · 15 mL). The organic extracts
were combined, washed with brine, dried (Na2SO4),
and evaporated under reduced pressure. The residue
was purified by flash chromatography on silica gel.
4.3.9. 6-(3-Aminophenyl)-1-hexanol (5g). Compound 5g
was synthesized from 4g using general method C. The
crude product was purified by flash chromatography
(silica gel, dichloromethane/methanol 97:3). Yield 91%;
IR (NaCl) m: 3384 (OH), 2917 (NH), 1059 (C–O)
cmꢀ1 1H NMR (CDCl3) d: 7.09 (t, 1H, J = 6.0 Hz,
;
Ar), 6.55 (m, 3H, Ar), 3.59 (t, 2H, J = 6.6 Hz, CH2),
3.14 (s, 2H, NH2), 2.52 (t, 2H, J = 7.0 Hz, CH2), 1.67
(m, 4H, CH2), 1.34 (m, 4H, CH2); 13C NMR (CDCl3)
d: 147.0, 144.0, 129.1, 119.0, 115.5, 112.8, 62.8, 35.9,
32.7, 31.3, 29.1, 25.7.
4.3.10. 7-(3-Aminophenyl)-1-heptanol (5h).21a Com-
pound 5h was synthesized from 4h using general method
C. The crude product was purified by flash chromatogra-
phy (silica gel, hexanes/ethyl acetate 70:30). Yield 65%; IR
4.4.1. 3-(3-Nitrophenyl)-2-propyn-1-ol (4d). Compound
4d was synthesized from 3-iodonitrobenzene and prop-
argyl alcohol. The crude product was purified by flash
chromatography (silica gel, hexanes/ethyl acetate
75:25). Yield 43%; mp 46–48 ꢁC; IR (KBr) m: 3263
(OH), 1529 (NO2), 1023 (C–O) cmꢀ1; 1H NMR (CDCl3)
d: 8.29 (s, 1H, Ar), 8.17 (m, 1H, Ar), 7.74 (d, 1H,
J = 7.8 Hz, Ar), 7.51 (t, 1H, J = 8.0 Hz, Ar), 4.53 (s,
2H, CH2); 13C NMR (CDCl3) d: 148.1, 137.4, 129.4,
126.5, 124.4, 123.2, 90.0, 83.2, 51.4.
1
(NaCl) m: 3359 (OH), 2928 (NH), 1056 (C–O) cmꢀ1; H
NMR (CDCl3) d: 7.09 (m, Ar, 1H), 6.69 (m, Ar, 3H),
3.62 (t, 2H, J = 6.6 Hz, CH2), 2.53 (t, 2H, J = 6.6 Hz,
CH2), 1.57 (m, 4H, 2· CH2), 1.33 (m, 6H, 3· CH2)
NMR 13C (CDCl3) d: 142.2, 129.3, 124.3, 121.4, 117.3,
114.5, 63.0, 35.7, 32.7, 31.0, 29.1, 29.0, 25.6.
4.3.11. 3-(4-Aminophenyl)-1-propanol (8d).25 Compound
8d was synthesized from 7d using general method C. The
crude product was purified by flash chromatography
(silica gel, dichloromethane/methanol 95:5). Yield 63%;
4.4.2. 4-(3-Nitrophenyl)-3-butyn-1-ol (4e). Compound 4e
was synthesized from 3-iodonitrobenzene and 3-butyn-
1-ol. The crude product was purified by flash chroma-
tography (silica gel, hexanes/ethyl acetate 65:35). Yield
65%; mp 72–74 ꢁC; IR (KBr) m: 3323 (OH), 1524
1
IR (NaCl) m: 3366 (OH), 2916 (NH) cmꢀ1; H NMR
(acetone-d6) d: 7.01 (d, 2H, J = 7.6 Hz, Ar), 6.71 (d,
2H, J = 7.6 Hz, Ar), 3.73 (t, 2H, J = 6.0 Hz, CH2),
2.83 (t, 2H, J = 6.0 Hz, CH2), 2.71 (br s, 2H, NH2),
1.71 (t, 2H, J = 6.0 Hz, CH2); 13C NMR (acetone-d6)
d: 146.8, 131.2, 120.2, 115.2, 61.6, 35.8, 31.9.
1
(NO2) cmꢀ1; H NMR (CDCl3) d: 8.26 (m, 1H, Ar),
8.14 (m, 1H, Ar), 7.71 (m, 1H, Ar), 7.48 (t, 1H,
J = 8.0 Hz, Ar), 3.87 (m, 2H, CH2), 2.73 (m, 2H,
CH2); 13C NMR (CDCl3) d: 148.1, 137.4, 129.3, 126.5,
125.2, 122.7, 89.7, 80.1, 61.0, 23.7.
4.3.12. 4-(4-Aminophenyl)-1-butanol (8e).21a Compound
8e was synthesized from 7e using general method C. The
crude product was purified by flash chromatography
(silica gel, dichloromethane/methanol 95:5). Yield 50%;
4.4.3. 5-(3-Nitrophenyl)-4-pentyn-1-ol (4f). Compound 4f
was synthesized from 3-iodonitrobenzene and 4-pentyn-
1-ol. The crude product was purified by flash chroma-
tography (silica gel, hexanes/ethyl acetate 70:30). Yield
1
IR (NaCl) m: 3349 (OH), 2926 (NH) cmꢀ1; H NMR
1
(CDCl3) d: 7.04 (d, 2H, J = 7.7 Hz, Ar), 6.68 (d, 2H,
J = 7.7 Hz, Ar), 3.61 (t, 2H, J = 6.0 Hz, CH2), 2.78 (br
s, 2H, NH2), 1.69 (m, 4H, CH2); 13C NMR (CDCl3) d:
143.8, 132.3, 128.4, 114.9, 62.6, 35.3, 31.9, 25.9.
77%; IR (NaCl) m: 3357 (OH), 1530 (NO2) cmꢀ1; H
NMR (CDCl3) d: 8.24 (s, 1H, Ar), 8.13 (d, 1H,
J = 8.0 Hz, Ar), 7.68 (d, 1H, J = 7.0 Hz, Ar), 7.46 (t,
1H, J = 8.0 Hz, Ar), 3.83 (t, 2H, J = 6.0 Hz, CH2),
2.58 (t, 2H, J = 6.0 Hz, CH2), 1.89 (m, 2H, CH2); 13C
NMR (CDCl3) d: 148.0, 137.3, 129.2, 126.3, 125.6,
122.3, 92.6, 78.8, 61.4, 31.1, 15.9.
4.3.13. 5-(4-Aminophenyl)-1-pentanol (8f). Compound 8f
was synthesized from 7f using general method C. The
crude product was purified by flash chromatography
(silica gel, dichloromethane/ethanol 95:5). Yield 63%;
4.4.4. 6-(3-Nitrophenyl)-5-hexyn-1-ol (4g). Compound 4g
was synthesized from 3-iodonitrobenzene and 5-hexyn-
1-ol. The crude product was purified by flash chroma-
tography (silica gel, hexanes/ethyl acetate 75:25). Yield
1
IR (NaCl) m: 3349 (OH), 2930 (NH) cmꢀ1; H NMR
(CDCl3) d: 6.96 (d, 2H, J = 7.7 Hz, Ar), 6.61 (d, 2H,
J = 7.7 Hz, Ar), 3.61 (t, 2H, J = 6.5 Hz, CH2), 2.82 (br

6710
E. Moreau et al. / Bioorg. Med. Chem. 13 (2005) 6703–6712
88%; IR (NaCl) m: 3354 (OH), 1530 (NO2), 1063 (C–O)
cmꢀ1; 1H NMR (CDCl3) d: 8.05 (s, 1H, Ar), 7.98 (d, 1H,
J = 8.0 Hz, Ar), 7.55 (d, 1H, J = 7.7 Hz, Ar), 7.34 (t, 1H,
J = 8.0 Hz, Ar), 3.61 (t, 2H, J = 6.0 Hz, CH2), 3.07 (br s,
2H, NH2), 2.37 (t, 2H, J = 6.0 Hz, CH2), 1.63 (m, 4H,
CH2); 13C NMR (CDCl3) d: 147.9, 137.3, 129.2, 126.1,
125.7, 122.2, 93.1, 78.7, 61.9, 31.7, 24.8, 19.1.
4.5.1. N-(3-Hydroxyphenyl)-N0-(2-chloroethyl)urea (1a).
Compound 1a was synthesized from 3-hydroxyaniline
and 2-chloroethylisocyanate. The crude product was
purified by flash chromatography (silica gel, dichloro-
methane/methanol 99:1). Yield 96%; mp 117–119 ꢁC;
IR (KBr) m: 3310 (NH, OH), 1633 (C@O), 1250 (C–O)
1
cmꢀ1; H NMR (acetone-d6) d: 8.57 (s, Ph, 1H), 8.23
(s, 1H, NH), 7.25 (s, 1H, OH), 7.06 (m, 1H, Ar), 6.80
(m, 1H, Ar), 6.50 (m, 1H, Ar), 6.35 (m, NH, 1H), 3.64
(m, 2H, CH2), 3.55 (m, 2H, CH2); 13C NMR (acetone-
d6) d: 158.7, 156.8, 141.7, 130.4, 110.9, 110.3, 107.0,
44.8, 42.6.
4.4.5. 7-(3-Nitrophenyl)-6-heptyn-1-ol (4h). Compound
4h was synthesized from 3-iodonitrobenzene and 6-hep-
tyn-1-ol. The crude product was purified by flash chro-
matography (silica gel, hexanes/ethyl acetate 75:25).
Yield 77%; IR (NaCl) m: 3378 (OH), 1529 (NO2), 1049
(C–O) cmꢀ1
;
1H NMR (CDCl3) d: 8.17 (s, 1H, Ar),
4.5.2. N-(3-Hydroxybenzyl)-N0-(2-chloroethyl)urea (1b).
Compound 1b was synthesized from 2 and 2-chloroethy-
lisocyanate. The crude product was purified by flash
chromatography (silica gel, dichloromethane/methanol
95:5). Yield 56%; mp 106–109 ꢁC; IR (KBr) m: 3326
8.07 (m, 1H, Ar), 7.65 (m, 1H, Ar), 7.43 (m, 1H, Ar),
3.64 (m, 2H, CH2), 2.42 (m, 2H, CH2), 2.12 (m, 1H,
OH), 1.53 (m, 6H, CH2); 13C NMR (CDCl3) d: 148.0,
137.3, 129.2, 126.3, 125.8, 122.2, 93.3, 78.7, 62.6, 32.2,
28.2, 25.1, 19.3.
1
(NH, OH), 1636 (C@O), 1242 (C–O) cmꢀ1; H NMR
(acetone-d6) d: 8.09 (s, NH, 1H), 7.46 (s, 1H, Ar), 7.37
(m, 1H, Ar), 7.18 (t, 1H, J = 8.0 Hz, Ar), 6.95 (d, 1H,
J = 7.4 Hz, Ar), 6.15 (s, 1H, NH), 4.57 (s, 2H, CH2),
4.23 (br s, 1H, OH), 3.67 (m, 2H, CH2), 3.53 (m, 2H,
CH2); 13C NMR (acetone-d6) d: 156.0, 143.9, 141.0,
129.2, 120.7, 117.6, 117.3, 64.6, 44.8, 42.4.
4.4.6. 3-(4-Aminophenyl)-2-propyn-1-ol (7d).25 Com-
pound 7d was synthesized from 4-iodoaniline and prop-
argyl alcohol. The crude product was purified by flash
chromatography (silica gel, dichloromethane/ethanol
95:5). Yield 76%; mp 84–86 ꢁC; IR (KBr) m: 3374 (OH,
1
NH2), 2233 (C„C) cmꢀ1; H NMR (CDCl3) d: 7.24
(d, 2H, J = 7.0 Hz, Ar), 6.60 (d, 2H, J = 7.0 Hz, Ar),
4.57 (s, 2H, CH2), 3.69 (br s, NH2); 13C NMR (CDCl3)
d: 146.9, 133.1, 114.7, 113.1, 86.4, 85.1, 51.8.
4.5.3. N-[3-(2-Hydroxyethyl)phenyl]-N0-(2-chloroethyl)
urea (1c). Compound 1c was synthesized from 3 and
2-chloroethylisocyanate. The crude product was purified
by flash chromatography (silica gel, dichloromethane/
methanol 95:5). Yield 41%; mp 109–111 ꢁC; IR (KBr)
4.4.7. 4-(4-Aminophenyl)-2-butyn-1-ol (7e). Compound
7e was synthesized from 4-iodoaniline and 3-butyn-1-
ol. The crude product was purified by flash chromatog-
raphy (silica gel, dichloromethane/ethanol 95:5). Yield
1
m: 3330 (NH, OH), 1636 (C@O) 1246 (C–O) cmꢀ1; H
NMR (acetone-d6) d: 8.08 (s, 1H, NH), 7.33 (m, 2H,
Ar), 7.13 (m, 1H, Ar), 6.82 (d, 1H, J = 7.5 Hz, Ar),
6.15 (s, 1H, NH), 3.69 (m, 4H, CH2), 3.53 (m, 2H,
CH2), 2.93 (br s, 1H, OH), 2.74 (t, 2H, J = 7.0 Hz,
CH2); 13C NMR (acetone-d6) d: 177.3, 155.9, 140.9,
129.2, 123.1, 119.5, 116.7, 63.7, 44.8, 42.4, 40.3.
32%; IR (KBr) m: 3347 (OH, NH2), 2213 (C„C) cmꢀ1
;
1H NMR (CDCl3) d: 7.19 (d, 2H, J = 7.0 Hz, Ar), 6.54
(d, 2H; J = 7.0 Hz, Ar), 3.72 (t, 2H, J = 6.5 Hz, CH2),
2.62 (t, 2H, J = 6.5 Hz, CH2); 13C NMR (CDCl3) d:
146.4, 132.7, 114.8, 113.4, 83.9, 82.8, 61.3, 23.9.
4.5.4. N-[3-(3-Hydroxypropyl)phenyl]-N0-(2-chloroethyl)
urea (1d). Compound 1d was synthesized from 5d and
2-chloroethylisocyanate. The crude product was purified
by flash chromatography (silica gel, dichloromethane/
ethyl acetate 80:20). Yield 51%; mp 96–98 ꢁC; IR
(KBr) m: 3320 (NH, OH), 1636 (C@O), 1249 (C–O)
4.4.8. 5-(4-Aminophenyl)-2-pentyn-1-ol (7f).26 Com-
pound 7f was synthesized from 4-iodoaniline and 4-pen-
tyn-1-ol. The crude product was purified by flash
chromatography (silica gel, dichloromethane/ethanol
95:5). Yield 73%; mp 99–100 ꢁC; IR (KBr) m: 3443
1
1
(OH, NH2) cmꢀ1; H NMR (CDCl3) d: 7.17 (d, 2H,
cmꢀ1; H NMR (acetone-d6) d: 8.00 (s, 1H, NH), 7.36
J = 7.0 Hz, Ar), 6.54 (d, 2H, J = 7.0 Hz, Ar), 3.73 (t,
2H, J = 7.0 Hz, CH2), 3.18 (br s, 2H, NH2), 2.30 (t,
2H, J = 7.0 Hz, CH2), 1.81 (t, 2H, J = 7.0 Hz, CH2);
13C NMR (CDCl3) d: 146.2, 132.8, 114.9, 113.2, 86.9,
81.5, 61.8, 31.2, 16.0.
(s, 1H, Ar), 7.29 (m, 1H, Ar), 7.13 (t, 1H, J = 8.0 Hz,
Ar), 6.80 (d, 1H, J = 7.4 Hz, Ar), 6.09 (br s, NH, 1H),
3.68 (m, 2H, CH2), 3.55 (m, 4H, CH2), 2.63 (m, 2H,
CH2), 1.79 (m, 2H, CH2); 13C NMR (acetone-d6) d:
155.9, 143.8, 141.2, 129.2, 122.6, 119.1, 116.5, 61.7,
44.8, 42.5, 35.3, 32.8.
4.5. Typical synthesis of 2-chloroethylureas 1a–n
4.5.5. N-[3-(4-Hydroxybutyl)phenyl]-N0-(2-chloroethyl)
urea (1e). Compound 1e was synthesized from 5e and
2-chloroethylisocyanate. The crude product was purified
by flash chromatography (silica gel, dichloromethane/
methanol 97:3). Yield 41%; mp 72–74 ꢁC; IR (KBr): m:
2-Chloroethylisocyanate (1.640 mmol) was added drop-
wise to a cold solution (ice bath) of the appropriate ani-
line (1.370 mmol) in dry dichloromethane (15 mL/g of
aniline). The ice bath was then removed and the reac-
tion mixture was stirred at room temperature for 20 h.
After completion of the reaction, the solvent was evap-
orated under reduced pressure to give an off-white solid,
which was purified by flash chromatography on silica
gel.
1
3323 (NH, OH), 1635 (C@O), 1249 (C–O) cmꢀ1; H
NMR (CDCl3 et CD3OD) d: 7.83 (br s, 1H, NH), 7.15
(m, 3H, Ar), 6.75 (d, 1H, J = 6.8 Hz, Ar), 6.06 (br s,
1H, NH), 3.43 (m, 8H, CH2), 2.50 (t, 2H, J = 7.5 Hz,
CH2), 1.51 (m, 2H, CH2); 13C NMR (CDCl3 and

E. Moreau et al. / Bioorg. Med. Chem. 13 (2005) 6703–6712
6711
CD3OD) d: 156.3, 143.3, 138.9, 128.8, 123.1, 119.6,
116.9, 62.1, 44.4, 41.7, 35.5, 31.9, 27.2.
ethyl acetate 60/40). Yield 51%; IR (NaCl) m: 3351
1
(NH, OH), 1701 (C@O), 1248 (C–O) cmꢀ1; H NMR
(acetone-d6) d: 8.21 (br s, 1H, NH), 7.03 (m, 1H, Ar),
6.79 (d, 1H, J = 7.0 Hz, Ar), 6.71 (s, 1H, Ar), 6.57 (d,
1H, J = 7.9 Hz, Ar), 6.23 (br s, 1H, NH), 3.71 (m, 4H,
CH2), 3.45 (m, 2H, CH2) 2.60 (t, 2H, J = 7.0 Hz,
CH2); 13C NMR (acetone-d6) d: 155.8, 146.3, 129.3,
124.1, 122.1, 118.2, 115.2, 86.2, 82.5, 61.1, 44.7, 42.3,
23.7.
4.5.6. N-[3-(5-Hydroxypentyl)phenyl]-N0-(2-chloroethyl)
urea (1f). Compound 1f was synthesized from 5f and
2-chloroethylisocyanate. The crude product was purified
by flash chromatography (silica gel, dichloromethane/
methanol 97:3). Yield 31%; mp 92–95 ꢁC; IR (KBr): m:
3318 (NH, OH), 1641 (C@O), 1055 (C–O) cmꢀ1 1H
;
NMR (acetone-d6) d: 8.05 (s, 1H, NH), 7.31 (m, 2H,
Ar), 7.12 (t, 1H, J = 8.9 Hz, Ar), 6.78 (d, 1H,
J = 7.4 Hz, Ar), 6.13 (s, 1H, NH), 3.67 (t, 2H,
J = 7.0 Hz, CH2), 3.51 (m, 4H, CH2), 2.90 (s, 1H,
OH), 2.57 (t, 2H, J = 7.7 Hz, CH2) 1.56 (m, 4H, CH2),
1.40 (m, 2H, CH2); 13C NMR (acetone-d6) d: 155.8,
143.9, 141.1, 129.2, 122.5, 119.0, 116.4, 62.3, 44.8,
42.5, 36.5, 33.5, 32.0, 26.2.
4.5.11. N-[3-(5-Hydroxy-1-pentynyl)phenyl]-N0-(2-chloro-
ethyl) urea (1k). Compound 1k was synthesized from 6f
and 2-chloroethylisocyanate. The crude product was
purified by flash chromatography (silica gel, ethanol/ethyl
acetate 2/98). Yield 63%; mp: 86–88 ꢁC; IR (KBr) m: 3302
1
(NH, OH), 1684 (C@O), 1272 (C–O) cmꢀ1; H NMR
(acetone-d6) d: 8.12 (br s, 1H, NH), 7.03 (m, 1H, Ar),
6.79 (d, 1H, J = 7.0 Hz, Ar), 6.69 (s, 1H, Ar), 6.57 (d,
1H, J = 8.0 Hz, Ar), 3.74 (t, 2H, J = 7.0 Hz, CH2), 3.49
(m, 4H, CH2), 2.47 (t, 2H, J = 7.0 Hz, CH2), 1.23 (t, 2H,
J = 7.0 Hz, CH2); 13C NMR (acetone-d6) d: 156.1,
146.3, 129.2, 125.3, 124.4, 122.0, 118.0, 88.9, 81.3, 61.6,
45.1, 42.8, 37.3, 31.4, 16.0.
4.5.7. N-[3-(6-Hydroxyhexyl)phenyl]-N0-(2-chloroethyl)
urea (1g). Compound 1g was synthesized from 5g and
2-chloroethylisocyanate. The crude product was purified
by flash chromatography (silica gel, dichloromethane/
methanol 97:3). Yield 52%; mp 83–84 ꢁC; IR (KBr) m:
3323 (NH, OH), 1636 (C@O), 1245 (C–O) cmꢀ1 1H
;
(NMR CDCl3 and CD3OD) d: 8.16 (br s, 1H, NH),
7.32 (m, 3H, Ar), 6.70 (t, 1H, J = 6.5 Hz, Ar), 6.25 (br
s, 1H, NH), 3.66 (m, 6H, CH2), 2.55 (t, 2H,
J = 7.5 Hz, CH2), 1.45 (m, 4H, CH2), 1.23 (m, 4H,
CH2); 13C NMR (CDCl3 and CD3OD) d: 156.2, 144.1,
141.0, 129.2, 122.7, 119.2, 116.6, 62.4, 44.8, 42.5, 36.5,
33.6, 32.1, 29.7, 26.4.
4.5.12. N-[4-(3-Hydroxypropyl)phenyl]-N0-(2-chloroeth-
yl) urea (1l). Compound 1l was synthesized from 8d
and 2-chloroethylisocyanate. The crude product was
purified by flash chromatography (silica gel, hexanes/
ethyl acetate 60/40). Yield 51%; mp 113–115 ꢁC; IR
(KBr) m: 3323 (NH, OH), 1630 (C@O), 1268 (C–O)
1
cmꢀ1; H NMR (CDCl3) d: 8.23 (br s, 1H, NH), 7.30
(d, 1H, J = 7.9 Hz, Ar), 7.06 (d, 1H, J = 8.0 Hz, Ar),
6.36 (br s, 1H, NH), 3.58 (m, 4H, CH2), 3.42 (m, 2H,
CH2), 2.47 (m, 2H, CH2), 1.81 (m, 2H, CH2); 13C
NMR (CDCl3) d: 155.2, 138.2, 134.0, 128.5, 118.0,
63.3, 44.5, 43.1, 35.7, 30.4.
4.5.8. N-[3-(7-Hydroxyheptyl)phenyl]-N0-(2-chloroethyl)
urea (1h). Compound 1h was synthesized from 5h
and 2-chloroethylisocyanate. The crude product was
purified by flash chromatography (silica gel, dichloro-
methane/methanol 98:2). Yield 36%; mp 86–88 ꢁC; IR
(KBr) m: 3336 (NH, OH), 1656 (C@O), 1243 (C–O)
4.5.13. N-[4-(4-Hydroxybutyl)phenyl]-N0-(2-chloroethyl)
urea (1m). Compound 1m was synthesized from 8e and
2-chloroethylisocyanate. The crude product was purified
by flash chromatography (silica gel, hexanes/ethyl ace-
tate 60/40). Yield 87%; mp 143–146 ꢁC; IR (KBr) m:
cmꢀ1 1H NMR (acetone-d6) d: 8.01 (s, 1H, NH),
;
7.29 (m, 3H, Ar), 6.78 (m, 1H, Ar), 6.09 (s, 1H,
NH), 3.67 (m, 2H, CH2), 3.52 (m, 4H, CH2), 2.87
(m, 4H, CH2), 2.54 (m, 2H, CH2), 1.35 (m, 6H,
CH2); 13C NMR (acetone-d6) d: 156.9, 144.3, 138.2,
129.1, 124.3, 121.2, 118.5, 63, 44.7, 42.0, 35.8, 32.6,
31.1, 29.1, 29.0, 25.6.
1
3312 (NH), 1639 (C@O), 1244 (C–O) cmꢀ1; H NMR
(acetone-d6) d: 8.00 (br s, 1H, NH), 7.39 (d, 2H,
J = 8.0 Hz, Ar), 7.07 (d, 2H, J = 8.0 Hz, Ar), 6.50 (br
s, 1H, NH), 3.51 (m, 8H, CH2), 2.57 (t, 2H,
J = 7.5 Hz, CH2), 1.58 (m, 2H, CH2); 13C NMR (ace-
tone-d6) d: 155.9, 139.0, 136.3, 130.0, 119.2, 64.8, 42.8,
42.5, 42.4, 35.2, 19.7.
4.5.9. N-[3-(3-Hydroxy-1-propynyl)phenyl]-N0-(2-chloro-
ethyl) urea (1i). Compound 1i was synthesized from 6d
and 2-chloroethylisocyanate. The crude product was
purified by flash chromatography (silica gel, hexanes/
ethyl acetate 60/40). Yield 63%; IR (KBr) m: 3315
(NH, OH), 2229 (C„C), 1686 (C@O), 1243 (C–O)
4.5.14. N-[4-(5-Hydroxypentyl)phenyl]-N0-(2-chloroethyl)
urea (1n). Compound 1n was synthesized from 8f and 2-
chloroethylisocyanate. The crude product was purified
by flash chromatography (silica gel, ethanol/ethyl ace-
tate 2:98). Yield 67%; mp 124–126 ꢁC; IR (KBr) m:
1
cmꢀ1; H (NMR acetone-d6) d: 8.06 (br s, 1H, NH),
7.08 (m, 1H, Ar), 6.83 (d, 1H, J = 7.5 Hz, Ar), 6.75 (s,
1H, Ar), 6.63 (d, 1H, J = 7.9 Hz, Ar), 3.57 (m, 4H,
CH2), 2.04 (s, 2H, CH2); 13C NMR (acetone-d6) d:
155.2, 129.8, 123.3, 123.1, 118.0, 115.6, 86.7, 85.9,
51.6, 44.8, 42.3.
1
3320 (NH), 1627 (C@O), 1268 (C–O) cmꢀ1; H NMR
(CDCl3) d: 8.63 (br s, 1H, NH), 7.36 (d, 2H,
J = 7.9 Hz, Ar), 7.13 (d, 2H, J = 7.9 Hz, Ar), 6.43 (br
s, 1H, NH), 3.96 (t, 2H, J = 6.5 Hz, CH2), 3.57 (m,
6H, CH2), 2.57 (t, 2H, J = 7.5 Hz, CH2), 1.54 (m, 2H,
CH2), 1.42 (m, 2H, CH2); 13C NMR (CDCl3) d: 155.2,
129.5, 128.4, 123.2, 117.9, 60.6, 43.4, 40.9, 34.4, 32.7,
25.0, 19.2.
4.5.10. N-[3-(4-Hydroxy-1-butynyl)phenyl]-N0-(2-chloro-
ethyl)urea (1j). Compound 1j was synthesized from 6e
and 2-chloroethylisocyanate. The crude product was
purified by flash chromatography (silica gel, hexanes/

6712
E. Moreau et al. / Bioorg. Med. Chem. 13 (2005) 6703–6712
13. Maurizis, J.-C.; Rapp, M.; Azim, E.-M.; Gaudreault, R.
Acknowledgments
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1998, 26, 146–151.
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431–436.
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16. Amanomiya, Y.; Amano, S.; Wakabayashi, K. Jpn. Kokai
Tokkyo Koho JP 2003128639, 2003, p 49.
This research program has been realized under research
grants from the National Institute of Health Research
(Grants No. MOP-67782 and MOP-53078), the Cancer
Research Society Inc., a sponsorship from IMOTEP
ˆ
inc. and the Centre de Recherche de lꢂHopital Saint-
Franc¸ois dꢂAssise (studentship to S.F.). The technical
expertise of Jacques Lacroix for tumor cell inhibition
assays is also sincerely acknowledged.
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