Synthesis and Src kinase inhibitory activity of a series of 4-[(2,4-dichloro-5-methoxyphenyl)amino]-7-furyl-3-quinolinecarbonitriles

Article abstract of DOI:10.1021/jm061031t

Compound 1 (SKI-606, bosutinib), a 7-alkoxy-4-[(2,4-dichloro-5- methoxyphenyl)amino]-3-quinolinecarbonitrile, is a potent inhibitor of Src kinase activity. We previously reported that analogs of 1 with thiophene groups at C-7 retained the Src activity of

Full text of DOI:10.1021/jm061031t

7868
J. Med. Chem. 2006, 49, 7868-7876
Synthesis and Src Kinase Inhibitory Activity of a Series of
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-7-furyl-3-quinolinecarbonitriles
Diane H. Boschelli,*,† Biqi Wu,† Fei Ye,† Yan Wang,† Jennifer M. Golas,‡ Judy Lucas,‡ and Frank Boschelli‡
Chemical and Screening Sciences and Oncology, Wyeth Research, 401 North Middletown Road, Pearl RiVer, New York 10965
ReceiVed August 28, 2006
Compound 1 (SKI-606, bosutinib), a 7-alkoxy-4-[(2,4-dichloro-5-methoxyphenyl)amino]-3-quinolinecar-
bonitrile, is a potent inhibitor of Src kinase activity. We previously reported that analogs of 1 with thiophene
groups at C-7 retained the Src activity of the parent compound. The corresponding C-7 furan analogs were
prepared and it was found that the 3,5-substituted furan analog had increased activity compared to that of
the 2,5-substituted furan isomer. Addition of a methoxy group at C-6 decreased the Src inhibitory activity
of the C-7 2,5-substituted furan analog but increased the activity of the C-7 3,5-substituted furan isomer.
This compound, 10, was a more potent Src inhibitor than 1 in both enzymatic and cell-based assays. The
kinase selectivity profile of 10 was similar to that of 1, with 10 also inhibiting the activity of Abl and Lck.
When tested in a solid tumor xenograft model, 10 had comparable oral activity to that of 1.
Introduction
the Src enzyme assay, it had reduced activity in the Src cell
assay.29 The activity of the C-7 thiophene analogs led us to
pursue other heteroaryl groups at this position, including the
C-7 furan analogs presented here.
The tyrosine kinase Src is a member of a family of related
kinases known as the SFKs (Src family kinases) that function
as key regulators of signal transduction pathways. Src is the
prototype member of this family and was first exemplified by
its oncogenic viral variant v-Src. It was shown over 25 years
ago that c-Src, the cellular counterpart of v-Src, encodes a
tyrosine specific kinase, which unlike v-Src is tightly regulated.
Src has been the focus of extensive studies,1,2 and recently, there
has been an upsurge in interest in pursuing Src as an oncology
target.3,4 Some of the renewed attention in Src is a result of
studies showing its important role in tumor progression and
metastatic growth.5 Phosphorylation of focal adhesion kinase
by Src results in increased cell motility, while Src-mediated
phosphorylation of â-catenin weakens E-cadherin-associated
cell-cell contacts.6 This loosening of the tissue’s structure
allows for the movement and spreading of cancer cells. In
addition, vascular endothelial growth factor induced vascular
permeability is dependent on Src kinase activity.7,8 There are
several reports that indicate small molecule Src inhibitors
prevent tumor cell extravasation.7,9-15 Another reason for the
renewed interest in Src is the discovery that several Src inhibitors
not only inhibit Abl kinase more potently than Gleevec
(imatinib), an Abl inhibitor that is the first line of treatment for
chronic myelogenous leukemia (CML), but also block the
activity of several Gleevec-resistant Abl mutations.16-19 The Src/
Abl dual inhibitor BMS-354825 (dasatinib) was recently ap-
proved by the FDA for the treatment of CML.20-23
Compound 1 (SKI-606, bosutinib), a 7-alkoxy-3-quinolin-
ecarbonitrile, is a dual inhibitor of Src and Abl kinases that is
currently in clinical trials for the treatment of both solid tumors
and CML.24-27 It was previously disclosed that related 3-quino-
linecarbonitriles, having a 3,5- or 2,5-disubstituted thiophene
at C-7, analogs 2a and 2b, retained much of the activity of 1
when tested in both a Src enzyme assay and a cell proliferation
assay employing Src-transformed rat fibroblasts.28 While the
C-7 phenyl analog 2c had comparable activity to 2a and 2b in
Chemistry
As depicted in Scheme 1, tetrakis(triphenylphosphine)-
palladium(0)-catalyzed Suzuki coupling of the C-7 bromo
intermediate 328 with 2-formyl-4-furanboronic acid provided the
intermediate aldehyde 4. Reductive amination of 4 with 1-me-
thylpiperazine and sodium triacetoxyborohydride resulted in 5.
In a similar fashion, dichlorobis(triphenylphosphine)palladium-
(II)-catalyzed Stille coupling of 3 with tributyl[5-(1,3-dioxolan-
2-yl)-2-furanyl]stannane,30 followed by acid hydrolysis, provided
aldehyde 6. Subsequent reductive amination of 6 with 1-meth-
ylpiperazine resulted in 7. By following the reaction sequence
used to convert 3 to 5, the C-7 triflate intermediate 829 was
reacted with 2-formyl-4-furanboronic acid to provide aldehyde
* To whom correspondence should be addressed. Phone: 845-602-3567.
Fax: 845-602-5561. E-mail: bosched@wyeth.com.
† Chemical and Screening Sciences.
‡ Oncology.
10.1021/jm061031t CCC: $33.50 © 2006 American Chemical Society
Published on Web 11/11/2006

Synthesis of Inhibitors of Src Kinase ActiVity
Journal of Medicinal Chemistry, 2006, Vol. 49, No. 26 7869
Scheme 1a
a Reagents: (a) 2-formyl-4-furanboronic acid, (Ph3P)4Pd, DME, satd aq NaHCO3; (b) 1-methylpiperazine, Na(OAc)3BH, CH2Cl2, HOAc, NMP (for 5) or
DMF (for 7 and 10); (c) (1) tributyl[5-(1,3-dioxolan-2-yl)-2-furanyl]stannane, (Ph3P)2PdCl2, dioxane; (2) 2 N HCl, THF.
Scheme 2a
a Reagents: (a) cyanoacetic acid, 1,3-diisopropylcarbodiimide, THF; (b) 3-bromo or 3-iodo-4-methoxyaniline, triethylorthoformate, i-PrOH; (c) phosphorus
oxychloride, acetonitrile.
9, which was converted to 10 via reductive amination with
1-methylpiperazine.
preparation of 7-bromo-3-quinolinecarbonitrile 13b from 3-bromo-
4-methoxyaniline.
While triflate 8 readily coupled with boronic acids and
stannane derivatives, its preparation from methyl vanillate was
rather cumbersome, requiring nine steps. To facilitate the
preparation of 6-methoxy analogs, an improved route to 8 was
essential. Another option was to identify a facile route to an
alternative intermediate, and it was decided to target the C-7
aryl iodine. It was envisioned that this analog could be
synthesized by adapting methodology initially utilized for the
large-scale preparation of 4-phenylamino-3-quinolinecarboni-
triles.31 As shown in Scheme 2, reaction of 2,4-dichloro-5-
methoxyaniline with cyanoacetic acid and 1,3-diisopropylcar-
bodiimide gave the acetamide derivative 11. Treatment of 11
with 3-iodo-4-methoxyaniline and triethylorthoformate in iso-
propanol provided 12a, which upon subsequent phosphorus
oxychloride-mediated ring closure in acetonitrile resulted in
formation of the desired 7-iodo-3-quinolinecarbonitrile 13a. The
versatility of this reaction sequence is highlighted by the ready
As shown in Scheme 3, we were pleased to observe that 13a
rapidly coupled with tributyl[5-(1,3-dioxolan-2-yl)-2-furanyl]-
stannane, with subsequent acid treatment providing aldehyde 14.
Reductive amination of 14 with 1-methylpiperazine resulted in
15. The analog of 5 lacking the methoxy group at C-5 of the
aniline, namely 17, was prepared by reaction of 1628 with
2-formyl-4-furanboronic acid, followed by reductive amination
(Scheme 4). The isomer of 5 where the furan substituent is at
C-6, namely 20, was prepared from the C-6 bromo derivative
1828 by a slightly different route. Intermediate 19 was obtained
by reductive amination of 4-bromo-2-furaldehyde with 1-me-
thylpiperazine. In situ formation of the trimethylstannane deriva-
tive of 19 by reaction with hexamethylditin in the presence of
tetrakis(triphenylphosphine)palladium(0) and subsequent cou-
pling with 18 provided 20. Analogs of 10 were readily obtained
by varying the amine used in the reductive amination reaction

7870 Journal of Medicinal Chemistry, 2006, Vol. 49, No. 26
Boschelli et al.
Scheme 3a
a Reagents: (a) (1) tributyl[5-(1,3-dioxolan-2-yl)-2-furanyl]stannane, (Ph3P)2PdCl2, dioxane; (2) 2 N HCl, THF; (b) 1-methylpiperazine, Na(OAc)3BH,
CH2Cl2, NMP, HOAc.
Scheme 4a
a Reagents: (a) (1) 2-formyl-4-furanboronic acid, (Ph3P)4Pd, DME, satd aq NaHCO3; (2) 1-methylpiperazine, Na(OAc)3BH, CH2Cl2, NMP, HOAc; (b)
1-methylpiperazine, Na(OAc)3BH, CH2Cl2, HOAc; (c) (Me3Sn)2, (Ph3P)4Pd, dioxane; (d) morpholine or 2 M dimethylamine in THF or 1-phenylpiperazine,
Na(OAc)3BH, CH2Cl2, DMF, HOAc.
of 9 (Scheme 4). This route was used to prepare 21-23, the
morpholine, dimethylamine, and N-phenylpiperazine analogs.
An alternative route to 10 based on the chemistry used to
prepare 13a and 13b was investigated. To this end, as shown
in Scheme 5, palladium-catalyzed coupling of 2-iodo-4-nitroani-
sole with 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2-
furancarboxaldehyde provided 24. Reductive amination of 24
with 1-methylpiperazine led to 25, with subsequent catalytic
hydrogenation of the nitro group giving aniline 26. Intermediate
26 was also prepared by in situ conversion of 19 to the
corresponding boronic acid, followed by coupling to 3-iodo-4-
methoxyaniline. Reaction of 26 and 11 with triethylorthoformate
in iso-propanol and subsequent ring closure with phosphorus
oxychloride in butyronitrile provided 10.
10, had an IC50 of 0.78 nM in the Src enzyme assay and an
IC50 of 15 nM in the Src cell assay, making 10 a more potent
Src inhibitor than 1. This increase in activity correlated with
what was seen in a series of C-7 alkenyl and alkynyl 3-quino-
linecarbonitriles, where the C-6 methoxy analogs were consis-
tently more potent than the C-6 unsubstituted analogs.32,33
However, these results contrasted with what was observed with
the C-7 phenyl analogs where the N-ethylpiperazine analog of
2c was a more potent Src inhibitor than its C-6 methoxy
derivative.29 Interestingly, 15, the C-6 methoxy analog of 7,
had reduced activity compared to that of 7. Therefore, there is
a large disparity in the activity of 10 and its 2,5-isomer 15,
with 15 having an IC50 in the Src enzyme assay of 13 nM and
an IC50 in the Src cell assay of 550 nM.
We previously reported several examples where removal of
the methoxy group at C-5 of the aniline headpiece lead to
decreased Src activity.33-35 This analog of 5, namely 17, was
less potent than 5 in both the Src enzyme and cell assays. We
also previously showed that several C-6-substituted 3-quinoli-
necarbonitriles were less potent than their corresponding C-7-
substituted isomers, with these substituents including alkoxy,36
Results and Discussion
As shown in Table 1, the 3,5-disubstituted furan analog 5
was about 3-fold more potent than the 2,5-isomer 7 in both the
Src enzyme and cell assays. This is in contrast to what was
seen with the corresponding thiophene derivatives 2a and 2b,
which were equipotent. The 6-methoxy analog of 5, namely

Synthesis of Inhibitors of Src Kinase ActiVity
Journal of Medicinal Chemistry, 2006, Vol. 49, No. 26 7871
Scheme 5a
the most robust activity against HT29 tumors, therefore, this
colon line was chosen for an in vivo study with 10.26 The tumors
were staged to approximately 250 mg in size prior to a single
daily oral administration of 25, 50, and 150 mg/kg of 10 for 21
days. As shown in Figure 1, a dose response was observed in
this model. The 150 mg/kg dose of 10 provided a T/C of 38%
at day 21, with no toxicity seen in any of the animals.
Conclusion
Continuing optimization of the 4-[2,4-dichloro-5-methoxy-
phenyl)]amino-3-quinolinecarbonitrile series of Src inhibitors
resulted in the identification of 10, a C-7 3,5-disubstituted furan
derivative. This analog was more potent than its 2,5-disubstituted
furan isomer 15 in inhibiting Src activity in vitro. In the course
of this work, a concise synthetic route to a key intermediate
was developed that allowed for the facile preparation of 10.
The new Src kinase inhibitor reported here demonstrated in vivo
activity in a colon tumor xenograft model, and further studies
with 10 (SKI-758) are underway.
a Reagents: (a) 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2-furan-
carboxaldehyde, (Ph3P)4Pd, DME, satd aq NaHCO3; (b) 1-methylpiperazine,
Na(OAc)3BH, CH2Cl2, NMP, HOAc; (c) 10% Pd on C, H2, MeOH; (d) (1)
11, triethylorthoformate, i-PrOH; (2) phosphorus oxychloride, butyronitrile;
(e) (1) tri-iso-propyl borate, n-butyl lithium, hexane, THF; (2) [1,1′bis-
(diphenylphosphino)ferrocene]-dichloropalladium(II) complex with dichlo-
romethane, 3-iodo-4-methoxyaniline, DME, aq Na2CO3.
Experimental Section
General Methods. Melting points were determined in open
capillary tubes on a Meltemp melting point apparatus and are
1
uncorrected. H NMR spectra were recorded using a DRX-400
spectrometer. Chemical shifts (δ) are in parts per million referenced
to Me4Si. Electrospray (ES) mass spectra were recorded in positive
mode on a Micromass Platform spectrometer. Electron impact (EI)
and high-resolution mass spectra were obtained on a Finnigan MAT-
90 spectrometer. Solvents and reagents obtained from commercial
sources were used without purification, unless noted. The reported
yields are for purified material and are not optimized. Reactions
were carried out under an inert atmosphere, either nitrogen or argon.
Flash chromatography was performed with Baker 40 µM silica gel.
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-7-(5-formyl-3-fu-
ryl)-3-quinolinecarbonitrile (4). A mixture of 328 (429 mg, 1.60
mmol), 2-formyl-4-furanboronic acid (280 mg, 2.01 mmol), and
tetrakis(triphenylphosphine)palladium(0) (20 mg) in 20 mL of
ethylene glycol dimethyl ether and 14 mL of saturated aqueous
sodium bicarbonate was heated at reflux for 2 h and then cooled to
room temperature. The reaction mixture was partitioned between
dichloromethane and water. The aqueous layer was extracted with
ethyl acetate. The organic layers were combined, dried over
magnesium sulfate, filtered, and concentrated in vacuo. Diethyl ether
was added to the residue, and the solid was collected by filtration
to provide 348 mg (78% yield) of 4 as a light yellow solid, mp
thiophene,28 along with ethenyl and ethynyl groups.32,33 As
expected based on these earlier findings, the isomer of 5 where
the furan group is at C-6, namely 20, had reduced activity
compared to 5.
The activity in the Src enzyme and cell assays of analogs of
10, wherein the 1-methylpiperazine group was replaced with
other amines, is shown in Table 1. While the morpholine analog
21 was slightly less potent than 10, the dimethylamine analog,
22, retained the activity of 10. Reduced activity was observed
with the 1-phenylpiperazine analog, 23, in both the enzyme and
cell assays (IC50 ) 3.6 and 34 nM, respectively). When tested
against a panel of kinases, 10 had IC50 values of greater than 1
µM for the inhibition of CDK4, AKT, KDR, and PDK-1 and
an IC50 of 230 nM for the inhibition of EGFR. Potent activity
was seen against Abl kinase, with 10 having an IC50 of 0.40
nM in an enzymatic Abl assay. This dual inhibition of Src and
Abl kinases was also observed with 1 and other related C-7
alkoxy 3-quinolinecarbonitriles.25,35 For the C-7 alkoxy analogs,
the magnitude of the Abl inhibition correlated with that of Src.
However, 5, 22, and 23 had comparable Abl activities, with
IC50 values in the range of 0.43 to 0.68 nM, while the Src IC50
values for these three analogs were 2.7, 0.75, and 3.6 nM,
respectively. In a cell proliferation assay with Lck-transformed
rat fibroblasts, 10 had an IC50 of 20 nM, demonstrating a lack
of selectivity for Src over another SFK.
In pharmaceutical profiling assays, 10 had a permeability of
2 ×10-6 cm/s in a PAMPA assay, with low solubility at neutral
pH. However, as expected due to the presence of the N-methyl
piperazine group, decreasing the pH to 4.5 increased the
solubility to 63 µg/mL. After a 30 min incubation with rat liver
microsomes, 72% of the compound remained unchanged. Prior
to testing in a xenograft assay, a stability study with nude mouse
liver microsomes was performed and 10 was found to have an
estimated half-life of 32 min. Nude mice were given a single
oral dose of 50 mg/kg of 10 in a vehicle consisting of 0.5%
methylcellulose and 0.4% polysorbate 80. The plasma concen-
trations of 10 at 4, 8, and 24 h were determined to be 1140,
1030, and 103 ng/mL, respectively, exposure levels that should
support once a day dosing. When administered orally in several
solid tumor xenograft models, 1 was previously shown to have
1
246-248 °C; H NMR (DMSO-d6/TFA) δ 3.90 (s, 3H), 7.61 (s,
1H), 7.89 (s, 1H), 8.19 (s, 1H), 8.25 (s, 1H), 8.34 (d, J ) 10 Hz,
1H), 8.84 (d, J ) 10 Hz, 1H), 8.98 (s, 1H), 9.23 (s, 1H), 9.76 (s,
1H); MS 438.0 (M + H)+. Anal. (C22H13Cl2N3O3‚1.75H2O) C, H,
N.
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-7-{5-[(4-methylpip-
erazin-1-yl)methyl]-3-furyl}-3-quinolinecarbonitrile (5). A mix-
ture of 4 (150 mg, 0.34 mmol) and 1-methylpiperazine (0.19 mL,
1.71 mmol) in 4 mL of dichloromethane and 1 mL of 1-methyl-
2-pyrrolidinone was cooled to 0 °C. Sodium triacetoxyborohydride
(370 mg, 1.75 mmol) was added followed by 0.08 mL of acetic
acid. The resulting mixture was stirred at 0 °C for 10 min then at
room temperature for 3 h. The mixture was partitioned between
ethyl acetate and saturated aqueous sodium bicarbonate. The organic
phase was dried over magnesium sulfate, filtered, and concentrated
in vacuo. The residue was purified by flash column chromatography,
eluting with a gradient of 10% methanol in ethyl acetate to 1%
ammonium hydroxide in 30% methanol in ethyl acetate. Trituration
with diethyl ether provided 109 mg (61% yield) of 5 as a white
solid, mp 210-212 °C; 1H NMR (DMSO-d6) δ 2.15 (s, 3H), 2.25-
2.39 (br s, 4H), 2.39-2.49 (br s, 4H), 3.54 (s, 2H), 3.86 (s, 3H),
6.98 (s, 1H), 7.30 (s, 1H), 7.71 (s, 1H), 7.91 (d, J ) 8 Hz, 1H),
8.03 (s, 1H), 8.40 (s, 1H), 8.44-8.56 (m, 2H), 10.13 (s, 1H); MS

7872 Journal of Medicinal Chemistry, 2006, Vol. 49, No. 26
Boschelli et al.
Table 1. Inhibition of Src Kinase Activity by 7-Furyl-3-quinolinecarbonitriles
Src enzyme
IC50 (nM)
Src cells
IC50 (nM)
isomer
X
Y
NRR′
1
3.835
3.8
2.3
5.0
2.7
7.5
0.78
13
11
84
1.5
0.75
3.6
10024
6928
6428
39029
46
120
15
550
260
2800
31
2a
2b
2c
5
3,5
2,5
1,4-phenyl
3,5
2,5
S
S
H
H
H
H
H
OMe
OMe
N-Me-piperazine
N-Me-piperazine
N-Me-piperazine
N-Me-piperazine
N-Me-piperazine
N-Me-piperazine
N-Me-piperazine
O
O
O
O
7
10
15
17
20
21
22
23
3,5
2,5
des 5-OMe isomer of 5
6-furyl isomer of 5
3,5
3,5
3,5
O
O
O
OMe
OMe
OMe
morpholine
NMe2
N-Ph-piperazine
21
34
(48% yield) of 6 as a yellow solid, mp > 250 °C; 1H NMR (DMSO-
d6/TFA) δ 3.87 (s, 3H), 7.43 (s, 1H), 7.67 (d, J ) 4 Hz, 1H), 7.76
(d, J ) 4 Hz, 1H), 7.79 (s, 1H), 8.26 (d, J ) 9 Hz, 1H), 8.34 (s,
1H), 8.72 (d, J ) 9 Hz, 1H), 8.87 (s, 1H), 9.72 (s, 1H); MS 438.3
(M + H+). Anal. (C22H13Cl2N3O3) C, H, N.
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-7-{5-[(4-methyl-1-
piperazinyl)methyl]-2-furyl}-3-quinolinecarbonitrile (7). 1-Meth-
ylpiperazine (0.065 mL, 0.56 mmol) was added to a suspension of
6 (200 mg, 0.45 mmol) in 3 mL of dichloromethane and 1 mL of
N,N-dimethylformamide. The reaction mixture was cooled to 0 °C
and sodium triacetoxyborohydride (500 mg, 2.36 mmol) was added.
After stirring at 0 °C for 1 h, a catalytic amount of acetic acid was
added and the reaction mixture was allowed to warm to room
temperature. The reaction was quenched by the addition of water
and then partitioned between saturated aqueous sodium bicarbonate
and dichloromethane. The organic layer was dried over sodium
sulfate, filtered, and concentrated in vacuo. The residue was purified
by flash column chromatography, eluting with a gradient of 10%
methanol in dichloromethane to 20% methanol in dichloromethane
to provide 95 mg (40% yield) of 7 as a light yellow solid, mp 157-
160 °C; 1H NMR (DMSO-d6/TFA) δ 2.82 (s, 3H), 3.24 (br s, 4H),
3.49 (br s, 4H), 3.88 (s, 3H), 4.07 (s, 2H), 6.75 (d, J ) 3 Hz, 1H),
7.42 (d, J ) 3 Hz, 1H), 7.47 (s, 1H), 7.83 (s, 1H), 8.13-8.26 (m,
2H), 8.69 (d, J ) 9 Hz, 1H), 8.92 (s, 1H); MS 522.3 (M + H)+.
Anal. (C27H25Cl2N5O2‚0.9 H2O) C, H, N.
Figure 1. Antitumor activity of 10 vs an HT-29 xenograft. Tumors
were staged to approximately 250 mg in volume prior to oral dosing
at 25, 50, and 150 mg/kg once a day for 21 days, with 10 animals per
group.
522.1, 524.1 (M + H)+; HRMS calcd, 522.14581; found, 522.14558
(M + H)+. Anal. (C27H25Cl2N5O2‚0.25H2O) C, H. N: calcd, 13.29;
found, 12.81.
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-7-(5-formyl-3-fu-
ryl)-6-methoxy-3-quinolinecarbonitrile (9). A mixture of 829 (835
mg, 1.60 mmol), 2-formyl-4-furanboronic acid (446 mg, 3.21
mmol), and tetrakis(triphenylphosphine)palladium(0) (20 mg) in 40
mL of ethylene glycol dimethyl ether and 25 mL of saturated
aqueous sodium bicarbonate was heated at reflux for 3 h and then
cooled to room temperature. The reaction mixture was partitioned
between dichloromethane and water. The aqueous layer was
extracted with 10% methanol in ethyl acetate. The organic layers
were combined, dried over magnesium sulfate, filtered, and
concentrated in vacuo. Diethyl ether was added to the residue, and
the solid was collected by filtration to provide 723 mg (48% yield)
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-7-(5-formyl-2-fu-
ryl)-3-quinolinecarbonitrile (6). A mixture of 328 (200 mg, 0.42
mmol), tributyl[5-(1,3-dioxolan-2-yl)-2-furanyl]stannane30 (220 mg,
0.50 mmol), and a catalytic amount of dichlorobis(triphenylphos-
phine)palladium(II) in 5 mL of dioxane was heated at reflux for 4
h. The mixture was concentrated in vacuo and partitioned between
ethyl acetate and saturated aqueous sodium chloride. The organic
layer was washed with water, dried over sodium sulfate, and
concentrated in vacuo to provide 130 mg (64% yield) of 4-[(2,4-
dichloro-5-methoxyphenyl)amino]-7-[5-(1,3-dioxolan-2-yl)-2-furyl]-
3-quinolinecarbonitrile as a yellow solid.
1
of 9 as a light yellow solid, mp 238-241 °C; H NMR (DMSO-
d6) δ 3.88 (s, 3H), 4.09 (s, 3H), 7.38 (s, 1H), 7.76 (s, 1H), 8.01 (s,
1H), 8.29 (br s, 2H), 8.48 (s, 1H), 8.77 (s, 1H), 9.71 (s, 1H), 9.87
(s, 1H); MS 468.0 (M + H)+; HRMS calcd, 468.05124; found,
468.0511(M + H)+.
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-6-methoxy-7-{5-
[(4-methylpiperazin-1-yl)methyl]-3-furyl}-3-quinolinecarboni-
trile (10). A mixture of 9 (200 mg, 0.43 mmol) and 1-methylpip-
A solution of 4-[(2,4-dichloro-5-methoxyphenyl)amino]-7-[5-
(1,3-dioxolan-2-yl)-2-furyl]-3-quinolinecarbonitrile (90 mg, 0.19
mmol) in 2 mL of tetrahydrofuran and 1 mL of 2 N hydrochloric
acid was stirred at room temperature for 4 h. The mixture was
partitioned between ethyl acetate and saturated sodium bicarbonate.
The organic layer was dried over sodium sulfate and filtered through
silica gel. The filtrate was concentrated in vacuo to provide 40 mg

Synthesis of Inhibitors of Src Kinase ActiVity
Journal of Medicinal Chemistry, 2006, Vol. 49, No. 26 7873
erazine (0.24 mL, 2.2 mmol) in 5 mL of dichloromethane and 1
mL of N,N-dimethylformamide was cooled to 0 °C. Sodium
triacetoxyborohydride (470 mg, 2.22 mmol) was added in portions,
followed by a few drops of acetic acid. The resulting mixture was
stirred at 0 °C for 10 min then at room temperature for 5.5 h. The
mixture was partitioned between ethyl acetate and saturated aqueous
sodium bicarbonate. The organic phase was dried over magnesium
sulfate, filtered, and concentrated in vacuo. The residue was purified
by flash column chromatography, eluting with a gradient of 10%
methanol in ethyl acetate to 1% ammonium hydroxide in 20%
methanol in ethyl acetate to provide 120 mg (51% yield) of 10 as
a light yellow solid, mp 179-181 °C; 1H NMR (DMSO-d6) δ 2.15
(s, 3H), 2.23-2.36 (br s, 4H), 2.38-2.49 (br s, 4H), 3.54 (s, 2H),
3.87 (s, 3H), 4.06 (s, 3H), 7.01 (s, 1H), 7.33 (s, 1H), 7.74 (s, 1H),
7.94 (s, 1H), 8.10 (s, 1H), 8.28 (s, 1H), 8.43 (s, 1H), 9.82 (s, 1H);
MS 552.1 (M + H)+; HRMS calcd, 552.15638; found, 552.15599
(M + H)+. Anal. (C28H27Cl2N5O3‚0.25H2O) C, H, N.
3H), 7.33 (s, 1H), 7.74 (s, 1H), 7.86 (s, 1H), 8.39 (s, 1H), 8.43 (s,
1H), 9.61 (s, 1H); MS 500.0 (M + H)+. Anal. (C18H12Cl2IN3O2‚
H2O) C, H, N.
7-Bromo-4-[(2,4-dichloro-5-methoxyphenyl)amino]-6-meth-
oxy-3-quinolinecarbonitrile (13b). A suspension of 12b (4.00 g,
8.50 mmol) in 200 mL of acetonitrile was heated to reflux, and
phosphorus oxychloride (5.0 mL) was added dropwise. The reaction
mixture was heated at reflux overnight, cooled to room temperature,
and concentrated in vacuo. The residue was cooled to 0 °C, and
saturated aqueous sodium bicarbonate was added. The mixture was
stirred for 1 h and then extracted with a large volume of ethyl
acetate. The organic layer was washed with saturated aqueous
sodium bicarbonate, dried over magnesium sulfate, and filtered.
The filtrate was reduced in volume until solids appeared. The solids
were collected by filtration, washing with diethyl ether and hexanes,
to provide 1.73 g (45% yield) of 13b as a light tan solid, mp >
1
250 °C. H NMR (400 MHz, DMSO-d6) δ 3.87 (s, 3H), 4.04 (s,
2-Cyano-N-(2,4-dichloro-5-methoxyphenyl)acetamide (11). A
solution of 2,4-dichloro-5-methoxyaniline (5.00 g, 26 mmol) and
cyanoacetic acid (2.28 g, 26.8 mmol) in 50 mL of tetrahydrofuran
was heated to reflux and 1,3-diisopropylcarbodiimide (4.2 mL, 26.8
mmol) was added dropwise. After 30 min, the mixture was cooled
to ∼15 °C in an ice bath. The solid was collected by filtration and
washed with tetrahydrofuran. The filtrate was slowly poured into
water and stirred for 30 min. The white solid was collected by
filtration, washing with water, and then it was dissolved in 500
mL of ethyl acetate. The solution was dried over sodium sulfate
and concentrated in vacuo to give 5.90 g (88% yield) of 11 as a
white solid, mp 180-181 °C; 1H NMR (DMSO-d6) δ 3.84 (s, 3H),
4.02 (s, 2H), 7.58 (s, 1H), 7.66 (s, 1H), 10.00 (s, 1H); MS 257.0
(M - H)-. Anal. (C10H8Cl2N2O2) C, H, N.
(2E/Z)-2-Cyano-N-(2,4-dichloro-5-methoxyphenyl)-3-[(3-iodo-
4-methoxyphenyl)amino]-2-propenamide (12a). To a suspension
of 11 (5.00 g, 19.30 mol) in 400 mL of iso-propanol was added
3-iodo-4-methoxyaniline (5.80 g, 23.16 mmol). This mixture was
heated to reflux to give a clear yellow solution. Triethylorthoformate
(8.60 mL, 52.11 mmol) was added dropwise, and the reaction
mixture was heated at reflux overnight. An additional 10 mL of
triethylorthoformate was added, and the mixture was heated at reflux
overnight. The mixture was allowed to cool to room temperature,
and the white solid collected by filtration, washing with iso-
propanol, and dried overnight at ∼40 °C under reduced pressure.
Suspension in hot ethyl acetate, followed by addition of cold
hexanes, gave 8.50 g (85% yield) of 12a as a yellow solid, mp
289-290 °C; MS 516.8 (M + H)+. Anal. (C18H14Cl2IN3O3‚0.5H2O)
C, H, N.
3H), 7.41 (s, 1H), 7.78 (s, 1H), 7.99 (s, 1H), 8.22 (s, 1H), 8.48 (s,
1H), 9.93 (s, 1H); MS 449.9 (M - H)-. Anal. (C18H12BrCl2N3O2)
C, H, N.
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-7-(5-formyl-2-fu-
ryl)-3-quinolinecarbonitrile (14). A mixture of 13a (1.20 g, 2.40
mmol), tributyl[5-(1,3-dioxolan-2-yl)-2-furanyl]stannane30 (1.50 g,
3.49 mmol), and a catalytic amount of dichlorobis(triphenylphos-
phine)palladium(II) in 50 mL of dioxane was heated at reflux for
4 h. The mixture was partitioned between ethyl acetate and brine.
The organic layer was dried over magnesium sulfate, filered, and
concentrated in vacuo. Purification by column chromatography,
eluting with a gradient of 100% hexane to 100% ethyl acetate,
provided 988 mg (80% yield) of 4-[(2,4-dichloro-5-methoxyphenyl}-
amino]-7-[5-(1,3-dioxolan-2-yl)-2-furyl]-6-methoxy-3-quinolinecar-
bonitrile as a yellow solid.
A solution of 4-[(2,4-dichloro-5-methoxyphenyl}amino]-7-[5-
(1,3-dioxolan-2-yl)-2-furyl]-6-methoxy-3-quinolinecarbonitrile (937
mg, 1.83 mmol) in 30 mL of tetrahydrofuran and 15 mL of 2 N
hydrochloric acid was stirred at room temperature overnight. The
mixture was slowly added to 80 mL of saturated sodium bicarbonate
and stirred for 40 min. The solids were collected by filtration,
washing with water, followed by ethyl acetate, to provide 649 mg
(76% yield) of 14 as a yellow solid, mp > 250 °C; 1H NMR
(DMSO-d6) δ 3.87 (s, 3H), 4.11 (s, 3H), 7.39 (s, 1H), 7.44 (d, J )
4 Hz, 1H), 7.71 (d, J ) 4 Hz, 1H), 7.76 (s, 1H), 8.05 (s, 1H), 8.33
(s, 1H), 8.49 (s, 1H), 9.72 (s, 1H), 9.92 (s, 1H); MS 468. (M +
H)+. HRMS calcd, 468.05124; found, 468.05104.
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-6-methoxy-7-{5-
[(4-methyl-1-piperazinyl)methyl]-2-furyl}-3-quinolinecarboni-
trile (15). 1-Methylpiperazine (0.24 mL, 2.16 mmol) was added
to a suspension of 14 (200 mg, 0.42 mmol) in 5 mL of
dichloromethane and 1 mL of 1-methyl-2-pyrrolidinone. The
reaction mixture was cooled to 0 °C, and sodium triacetoxyboro-
hydride (470 mg, 2.22 mmol) was added, followed by a few drops
of acetic acid. The reaction mixture was stirred at room temperature
overnight and then partitioned between saturated sodium bicarbonate
and ethyl acetate. The organic layer was dried over magnesium
sulfate, filtered, and concentrated in vacuo. The residue was purified
by flash column chromatography, eluting with a gradient of 100%
dichloromethane to 20% methanol in dichloromethane, to provide
(2E/Z)-3-[[3-Bromo-4-methoxyphenyl]amino]-2-cyano-N-(2,4-
dichloro-5-methoxyphenyl)-2-propenamide (12b). To a suspen-
sion of 11 (900 mg, 3.46 mmol) in 100 mL of iso-propanol was
added 3-bromo-4-methoxyaniline (700 mg, 3.46 mmol). The
mixture was heated to reflux and triethylorthoformate (3.3 mL, 19.8
mmol) was added dropwise. Heating at reflux was continued for 6
h. The mixture was filtered while still warm, and the white solid
was collected and washed with iso-propanol to give 376 mg (23%
yield) of 12b, mp > 250 °C; MS 467.7 (M - H)-. Anal. (C18H14-
BrCl2N3O3) C, H, N.
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-7-iodo-6-methoxy-
3-quinolinecarbonitrile (13a). To a suspension of 12a (720 mg,
1.39 mmol) in 40 mL of acetonitrile was added 0.2 mL of methanol.
The mixture was heated to reflux, and phosphorus oxychloride (1.24
mL, 13.9 mmol) was added dropwise. This solution was heated at
reflux overnight. After 24 h, the mixture was cooled in an ice bath,
and the solid was collected by filtration, washing with cold
acetonitrile (40 mL) and then suspended in tetrahydrofuran (100
mL). To both the acetonitrile filtrate and the tetrahydrofuran
suspension was added concentrated ammonium hydroxide, and the
mixtures were stirred for 1 h. Water was added, and stirring was
continued for 2 h. The resulting solids were combined, washed with
hot water, and dried under reduced pressure at ∼40 °C, overnight,
to provide 200 mg (29% yield) of 13a, as a yellow solid, mp 253-
1
164 mg (69% yield) of 15 as a yellow solid, mp 225-227 °C; H
NMR (DMSO-d6/TFA) δ 2.82 (s, 3H), 3.19 (br s, 4H), 3.49 (br s,
4H), 3.89 (s, 3H), 4.04 (s, 2H), 4.14 (s, 3H), 6.74 (d, J ) 3 Hz,
1H), 7.35 (d, J ) 3 Hz, 1H), 7.53 (s, 1H), 7.88 (s, 1H), 8.18 (s,
1H), 8.33 (s, 1H), 8.96 (s, 1H); MS 552.2 (M + H)+. Anal. (C28H27-
Cl2N5O3‚0.5H2O) C, H, N.
4-[(2,4-Dichlorophenyl)amino]-7-{5-[(4-methylpiperazin-1-
yl)methyl]-3-furyl}-3-quinolinecarbonitrile (17). A mixture of
1628 (310 mg, 0.78 mmol), 2-formyl-4-furanboronic acid (220 mg,
1.58 mmol), and tetrakis(triphenylphosphine)palladium(0) (20 mg)
in 15 mL of ethylene glycol dimethyl ether and 10 mL of saturated
aqueous sodium bicarbonate was heated at reflux for 1 h and then
cooled to room temperature. The reaction mixture was partitioned
1
254 °C; H NMR (400 MHz, DMSO-d6) δ 3.86 (s, 3H), 4.00 (s,

7874 Journal of Medicinal Chemistry, 2006, Vol. 49, No. 26
Boschelli et al.
between 10% methanol in ethyl acetate and water. The organic layer
was dried over magnesium sulfate, filtered and concentrated in
Vacuo. Diethyl ether was added to the residue and the solid was
collected by filtration to provide 130 mg (41% yield) of the
intermediate aldehyde derivative as a yellow-orange solid.
8.30 (s, 1H), 8.44 (s, 1H), 9.81 (s, 1H); MS 539.1 (M + H)+. Anal.
(C27H24Cl2N4O4‚0.50H2O) C, H, N.
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-6-methoxy-7-{5-
[(dimethylamino)methyl]-3-furyl}-3-quinolinecarbonitrile (22).
Compound 22 was prepared from 9 according to the route used to
prepare 10: mp 133-138 °C; 1H NMR (DMSO-d6) δ 2.20 (s, 6H),
3.49 (s, 2H), 3.87 (s, 3H), 4.07 (s, 3H), 7.03 (s, 1H), 7.38 (s, 1H),
7.76 (s, 1H), 7.95 (s, 1H), 8.13 (s, 1H), 8.30 (s, 1H), 8.45 (s, 1H),
9.82 (s, 1H); MS 497.1 (M + H)+; HRMS calcd, 497.11418; found,
497.11291 (M + H)+. Anal. (C25H22Cl2N4O3‚1.50H2O) C, H. N:
calcd, 10.68; found, 10.11.
A mixture of this aldehyde (106 mg, 0.26 mmol) and 1-meth-
ylpiperazine (0.15 mL, 1.35 mmol) in 4 mL of dichloromethane
and 1 mL of 1-methyl-2-pyrrolidinone was cooled to 0 °C. Sodium
triacetoxyborohydride (300 mg, 1.42 mmol) was added, followed
by a few drops of acetic acid. The resulting mixture was stirred at
0 °C for 10 min and then at room temperature for 2 h. The mixture
was partitioned between ethyl acetate and water. The organic phase
was dried over magnesium sulfate, filtered, and concentrated in
vacuo. The residue was purified by flash column chromatography,
eluting with a gradient of 10% methanol in ethyl acetate to 1%
ammonium hydroxide in 25% methanol in ethyl acetate. Trituration
with diethyl ether provided 48 mg (38% yield) of 17 as a light
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-6-methoxy-7-{5-
[(4-phenylpiperazin-1-yl)methyl]-3-furyl}-3-quinolinecarboni-
trile (23). Compound 23 was prepared from 9 according to the
1
route used to prepare 10: mp 201-203 °C; H NMR (DMSO-d6)
δ 2.52-2.62 (br s, 4H), 3.09-3.19 (br s, 4H), 3.34 (s, 2H), 3.87
(s, 3H), 4.07 (s, 3H), 6.77 (t, J ) 7 Hz, 1H), 6.92 (d, J ) 8 Hz,
2H), 7.09 (s, 1H), 7.20 (t, J ) 8 Hz, 2H), 7.38 (s, 1H), 7.76 (s,
1H), 7.95 (s, 1H), 8.14 (s, 1H), 8.32 (s, 1H), 8.45 (s, 1H), 9.83 (s,
1H); MS 614.1 (M + H)+; HRMS calcd, 614.17203; found,
614.17153 (M + H)+. Anal. (C33H29Cl2N5O3‚0.50H2O) C, N. H:
calcd, 4.85; found, 4.37.
1
yellow solid, mp 183-186 °C; H NMR (DMSO-d6/TFA) δ 2.84
(s, 3H), 3.06-3.62 (br s, 8H), 4.13 (s, 2H), 7.19 (s, 1H), 7.61 (dd,
J ) 8, 2 Hz, 1H), 7.68 (d, J ) 8 Hz, 1H), 7.90 (d, J ) 2 Hz, 1H),
8.12 (s, 1H), 8.16 (d, J ) 9 Hz, 1H), 8.64 (s, 1H), 8.69 (d, J ) 9
Hz, 1H), 9.01 (s, 1H); MS 492.0 (M + H)+. Anal. (C26H23-
Cl2N5O‚1.20H2O) C, H, N.
4-(2-Methoxy-5-nitrophenyl)-2-furaldehyde (24). To a mixture
of 2-iodo-4-nitroanisole (565 mg, 2.02 mmol) and 4-(4,4,5,5-
tetramethyl-1,3,2-dioxaborolan-2-yl)-2-furancarboxaldehyde (670
mg, 3.03 mmol) in 20 mL of ethylene glycol dimethyl ether and
12 mL of aqueous saturated sodium bicarbonate was added 80 mg
of tetrakis(triphenylphosphine)palladium(0). The mixture was heated
to reflux overnight then allowed to cool to room temperature. An
attempt to partition the reaction mixture between 10% methanol in
ethyl acetate and water led to a large amount of insoluble material.
These solids were collected by filtration and washed with water
and ethyl acetate to provide 259 mg (52% yield) of 24 as a light
1-[(4-Bromo-2-furyl)methyl]-4-methylpiperazine (19). To a
solution of 4-bromo-2-furaldehyde (500 mg, 2.86 mmol) in 20 mL
of dichloromethane was added 1-methylpiperazine (1.58 mL, 14.3
mmol). The solution was cooled to 0 °C, and sodium triacetoxy-
borohydride (3.03 g, 14.3 mmol) was added in portions, followed
by 0.07 mL of acetic acid. The reaction mixture was stirred at room
temperature overnight. Saturated aqueous sodium bicarbonate was
added, and the mixture was stirred for 2 h. The reaction mixture
was extracted with dichloromethane, and the organic phase was
washed with brine and dried over sodium sulfate. Filtration and
concentration in vacuo, followed by flash column chromatography,
eluting with a gradient of methanol in dichloromethane (0% to
20%), with a second flash column chromatography, eluting with a
gradient of methanol in ethyl acetate (0% to 15%) to 1%
concentrated ammonium hydroxide in 20% methanol in ethyl
1
brown solid; H NMR (DMSO-d6) δ 4.07 (s, 3H), 7.37 (d, J ) 9
Hz, 1H), 8.20-8.29 (m, 2H), 8.55 (d, J ) 3 Hz, 1H), 8.69 (s, 1H),
9.68 (s, 1H); MS 247.1 (M - H)-.
1-{[4-(2-Methoxy-5-nitrophenyl)-2-furyl]methyl}-4-methylpip-
erazine (25). A mixture of 24 (230 mg, 0.93 mmol) and 1-meth-
ylpiperazine (0.90 mL, 8.1 mmol) in 20 mL of dichloromethane
and 2 mL of 1-methylpyrrolidinone was cooled to 0 °C. Sodium
triacetoxyborohydride (1.21 g, 5.7 mmol) was added in portions,
followed by a few drops of acetic acid. The resulting mixture was
stirred at 0 °C for 10 min then at room temperature for 1.5 h. The
mixture was partitioned between ethyl acetate and saturated aqueous
sodium bicarbonate. The organic phase was dried over magnesium
sulfate, filtered, and concentrated in vacuo. The residue was purified
by flash column chromatography, eluting with a gradient of 20%
methanol in ethyl acetate to 1% ammonium hydroxide in 20%
methanol in ethyl acetate. Trituration with diethyl ether and hexane
provided 57 mg (18% yield) of 25 as a light yellow solid; 1H NMR
(DMSO-d6) δ 2.14 (s, 3H), 2.25-2.36 (br s, 4H), 2.38-2.46 (br s,
4H), 3.52 (s, 2H), 4.04 (s, 3H), 6.96 (s, 1H), 7.31 (d, J ) 8 Hz,
1H), 8.14-8.20 (m, 2H), 8.38 (d, J ) 3 Hz, 1H); MS 332.1 (M +
H)+. Anal. (C17H21N3O4) C, H, N.
1
acetate, provided 426 mg of 19 (58% yield) as a yellow oil; H
NMR (DMSO-d6) δ 2.13 (s, 3H), 2.29 (br s, 4H), 2.54 (br s, 4H),
3.46 (s, 2H), 6.48 (s, 1H), 7.82 (s, 1H); MS 259.0 (M +H)+.
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-6-{5-[(4-methyl-1-
piperazinyl)methyl]-3-furyl}-3-quinolinecarbonitrile (20). A mix-
ture of 19 (135 mg, 0.52 mmol), hexamethylditin (170 mg, 0.52
mmol), and tetrakis(triphenylphosphine)palladium(0) (42 mg) in 6
mL of 1,4-dioxane was heated at 103 °C for 3 h. To the reaction
mixture was added 1828 (200 mg, 0.47 mmol) and tetrakis-
(triphenylphosphine)palladium (0) (16 mg). The temperature was
increased to 110 °C, and the reaction mixture was kept at this
temperature for 20 h. After cooling to room temperature, the
reaction mixture was partitioned between dichloromethane and
saturated aqueous sodium bicarbonate. The organic phase was dried
over sodium sulfate, filtered, and concentrated in vacuo. The residue
was purified by flash column chromatography, eluting with a
gradient of dichloromethane to 10% methanol in dichloromethane.
The resultant oil was purified by preparative thin layer chroma-
tography, developing with 10% methanol in dichloromethane.
Trituration with hexane and ethyl acetate provided 24 mg of 20
(10% yield) as a yellow solid, mp 192-195 °C; 1H NMR (DMSO-
d6/TFA) δ 2.89 (s, 3H), 3.21-3.72 (br s, 8H), 3.91 (s, 3H), 4.43
(s, 2H), 7.32 (s, 1H), 7.62 (s, 1H), 7.92 (s, 1H), 8.09 (d, J ) 8 Hz,
1H), 8.43 (d, J ) 8 Hz, 1H), 8.58 (s, 1H), 8.99 (s, 1H), 9.22 (s,
1H); MS 522.1 (M + H)+. Anal. (C27H25Cl2N5O2‚1.30H2O) C, H,
N.
(4-Methoxy-3-{5-[(4-methylpiperazin-1-yl)methyl]-3-furyl}-
phenyl)amine (26). To a solution of 25 (396 mg, 1.19 mmol) in
20 mL of methanol was added 10% palladium on carbon (40 mg).
The resulting mixture was treated with hydrogen in a Parr shaker
until hydrogen uptake ceased. The reaction mixture was filtered
through Celite and the filtrate concentrated in vacuo to give 358
1
mg (100% yield) of 26 as a brown oil; H NMR (DMSO-d6) δ
2.14 (s, 3H), 2.29 (br s, 4H), 2.40 (br s, 4H), 3.49 (s, 2H), 3.72 (s,
3H), 4.61 (s, 2H), 6.47 (d, J ) 8 Hz, 1H), 6.58 (s, 1H), 6.78 (d, J
) 9 Hz, 1H), 6.80 (s, 1H), 7.91 (s, 1H); MS 302.1 (M + H)+.
Alternative Preparation of 4-[(2,4-Dichloro-5-methoxyphen-
yl)amino]-6-methoxy-7-{5-[(4-methylpiperazin-1-yl)methyl]-3-
furyl}-3-quinolinecarbonitrile (10). To a suspension of 11 (261
mg, 1.01 mmol) in 5 mL of iso-propanol was added triethylortho-
formate (0.504 mL, 3.03 mmol). The mixture was heated to reflux
and 26 (320 mg, 1.06 mmol) in 9 mL of iso-propanol was added
dropwise. This mixture was heated at reflux for 25 h. The mixture
4-[(2,4-Dichloro-5-methoxyphenyl)amino]-6-methoxy-7-[5-
(morpholin-4-ylmethyl)-3-furyl]-3-quinolinecarbonitrile (21). Com-
pound 21 was prepared from 9 according to the route used to
prepare 10: mp 164-166 °C; 1H NMR ((DMSO-d6) δ 2.39-2.46
(br s, 4H), 3.50-3.60 (complex m, 6H), 3.87 (s, 3H), 4.06 (s, 3H),
7.05 (s, 1H), 7.36 (s, 1H), 7.75 (s, 1H), 7.94 (s, 1H), 8.12 (s, 1H),

Synthesis of Inhibitors of Src Kinase ActiVity
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was allowed to cool to room temperature, and the solid was
collected by filtration, washing with iso-propanol, to provide 465
mg (81% yield) of (2E/Z)-2-cyano-N-(2,4-dichloro-5-methoxyphe-
nyl)-3-[(4-methoxy-3-{5-[(4-methyl-1-piperazinyl)methyl]-3-furanyl}-
phenyl)amino]-2-propenamide as a gray solid.
A suspension of (2E/Z)-2-cyano-N-(2,4-dichloro-5-methoxyphe-
nyl)-3-[(4-methoxy-3-{5-[(4-methyl-1-piperazinyl)methyl]-3-furanyl}-
phenyl)amino]-2-propenamide (196 mg, 0.34 mmol) in 3.3 mL of
butyronitrile was heated to 105 °C, and phosphorus oxychloride
(0.192 mL, 2.1 mmol) was added dropwise. The resultant mixture
was heated at 120 °C for 24 h. After cooling, the reaction mixture
was concentrated in vacuo, and the residue was treated with
saturated aqueous sodium carbonate, followed by extraction into
dichloromethane. The organic phase was dried over sodium sulfate,
filtered, and concentrated in vacuo. The residue was purified by
flash column chromatography, eluting with a gradient of dichlo-
romethane to 20% methanol in dichloromethane. Trituration with
diethyl ether gave 46 mg (24% yield) of 10 as a yellow solid.
Alternative Preparation of (4-Methoxy-3-{5-[(4-methylpip-
erazin-1-yl)methyl]-3-furyl}phenyl)amine (26). To a solution of
19 (1.43 g, 5.52 mmol) and tri-iso-propyl borate (1.76 g, 9.38 mmol)
in 20 mL of tetrahydrofuran at -78 °C was added 1.6 M n-butyl
lithium in hexane (5.38 mL, 8.61 mmol) over 10 min. After stirring
at -78 °C for 10 min, the temperature of the reaction mixture was
allowed to rise to room temperature. Water (1.0 mL) was added,
and the solvents were removed in vacuo. The residue was dissolved
in 20 mL of ethylene glycol dimethyl ether and 3-iodo-4-
methoxyaniline (1.06 mg, 4.25 mmol), and [1,1′-bis(diphenylphos-
phino)ferrocene]dichloropalladium(II) complex with dichloromethane
(1:1; 87 mg, 0.11 mol) were added. A solution of 2.25 g of sodium
carbonate in 6.5 mL of water was added, and the resulting mixture
was heated at reflux for 3 h. The mixture was cooled to room
temperature and partitioned between ethyl acetate and water. The
aqueous layer was further extracted with ethyl acetate, and the
organic layers were combined, washed with brine, dried over
sodium sulfate, filtered, and concentrated in vacuo. The residue
was purified by flash column chromatography, eluting with a
gradient of 5% methanol in dichloromethane to 10% to provide
900 mg (70% yield) of 26 as a dark red oil.
(15) Rucci, N.; Recchia, I.; Angelucci, A.; Alamanou, M.; Del Fattore,
A.; Fortunati, D.; Susa, M.; Fabbro, D.; Bologna, M.; Teti, A.
Inhibition of protein kinase c-Src reduces the incidence of breast
cancer metastases and increases survival in mice: Implications for
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Drug Des. ReV.sOnline 2004, 1, 203-214.
(17) Cortes, J.; Kantarjian, H. New targeted approaches in chronic myeloid
leukemia. J. Clin. Oncol. 2005, 23, 6316-6324.
Assay Protocols
The Src enzyme,35 Src cell,36 Abl enzyme,35 and Lck cell37
assays were performed as previously reported. The protocol used
for the HT29 xenograft study was also reported previously.26
Acknowledgment. The authors acknowledge the Wyeth
Analytical Chemical Technology Department for the spectral
data and pharmaceutical profiling results, the Wyeth Drug Safety
and Metabolism Department for the nude mouse microsome
stability and plasma level determinations, members of the Wyeth
Oncology Department for the kinase profiling data, and Carlo
Etienne for assistance with the xenograft study. We also thank
Drs. Dennis Powell, Kim Arndt, Jay Gibbons, Phil Frost, and
Tarek Mansour for their support.
(18) Manley, P. W.; Cowan-Jacob, S. W.; Mestan, J. Advances in the
structural biology, design and clinical development of Bcr-Abl kinase
inhibitors for the treatment of chronic myeloid leukaemia. Biochim.
Biophys. Acta 2005, 1754, 3-13.
(19) Martinelli, G.; Soverini, S.; Rosti, G.; Baccarani, M. Dual tyrosine
kinase inhibitors in chronic myeloid leukemia. Leukemia 2005, 19,
1872-1879.
(20) Shah, N. P.; Tran, C.; Lee, F. Y.; Chen, P.; Norris, D.; Sawyers, C.
L. Overriding Imatinib resistance with a novel ABL kinase inhibitor.
Science 2004, 305, 399-402.
(21) Lombardo, L. J.; Lee, F. Y.; Chen, P.; Norris, D.; Barrish, J. C.;
Behnia, K.; Castaneda, S.; Cornelius, L. A. M.; Das, J.; Doweyko,
A. M.; Fairchild, C.; Hunt, J. T.; Inigo, I.; Johnston, K.; Kamath,
A.; Kan, D.; Klei, H.; Marathe, P.; Pang, S.; Peterson, R.; Pitt, S.;
Schieven, G. L.; Schmidt, R. J.; Tokarski, J.; Wen, M.-L.; Wityak,
J.; Borzilleri, R. M. Discovery of N-(2-chloro-6-methyl-phenyl)-2-
(6-(4-(2-hydroxyethyl)-piperazin-1-yl)-2-methylpyrimidin-4-ylami-
no)thiazole-5-carboxamide (BMS-354825), a dual Src/Abl kinase
inhibitor with potent antitumor activity in preclinical assays. J. Med.
Chem. 2004, 47, 6658-6661.
(22) Talpaz, M.; Shah, N. P.; Kantarjian, H.; Donato, N.; Nicoll, J.;
Paquette, R.; Cortes, J.; O’Brien, S.; Nicaise, C.; Bleickardt, E.;
Blackwood-Chirchir, M. A.; Iyer, V.; Chen, T. T.; Huang, F.; Decillis,
A. P.; Sawyers, C. L. Dasatinib in imatinib-resistant Philadelphia
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2541.
Supporting Information Available: Elemental analysis data
for compounds 4-7, 10-13b, 15, 17, 20-23, and 25 and standard
deviations for Src inhibition data are shown in Table 1 (2 pages).
This material is available free of charge via the Internet at http://
pubs.acs.org.
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