Synthesis of novel alkyltriazole tagged pyrido[2,3-d]pyrimidine derivatives and their anticancer activity

Article abstract of DOI:10.1016/j.ejmech.2011.05.011

A series of novel alkyltriazole tagged pyrido[2,3-d]pyrimidine derivatives 5 and 6 was prepared starting from 2,3-active functional pyridine 1 via cyclization, propargylation followed by reaction with alkyl or perfluoroalkyl azides under Sharpless conditi

Full text of DOI:10.1016/j.ejmech.2011.05.011

European Journal of Medicinal Chemistry 46 (2011) 3462e3468
Contents lists available at ScienceDirect
European Journal of Medicinal Chemistry
journal homepage: http://www.elsevier.com/locate/ejmech
Original article
Synthesis of novel alkyltriazole tagged pyrido[2,3-d]pyrimidine derivatives and
their anticancer activity
C. Kurumurthy a, P. Sambasiva Rao a, B. Veera swamy a, G. Santhosh kumar a, P. Shanthan Rao a,
,
b
b
b
B. Narsaiah a , L.R. Velatooru , R. Pamanji , J. Venkateswara Rao
*
a Fluoroorganic Division, Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500607, India
b Biology Division, Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500607, India
a r t i c l e i n f o
a b s t r a c t
Article history:
A series of novel alkyltriazole tagged pyrido[2,3-d]pyrimidine derivatives 5 and 6 was prepared starting
from 2,3-active functional pyridine 1 via cyclization, propargylation followed by reaction with alkyl or
perfluoroalkyl azides under Sharpless conditions. All the compounds 5 and 6 were screened for anti-
cancer activity against three cancer cell lines such as U937, THP-1 and Colo205. The promising compounds
5b and 5e have been identified.
Received 4 March 2011
Received in revised form
3 May 2011
Accepted 4 May 2011
Available online 12 May 2011
Ó 2011 Elsevier Masson SAS. All rights reserved.
Keywords:
Pyrido[2,3-d]pyrimidine
Cyclisation
Propargylation
Perfluoroalkyl azides
Sharpless conditions
Anticancer activity
1. Introduction
and perfluoroalkyl triazole tagged pyrido[2,3-d]pyrimidines and
screened for anticancer activity against three cancer cell lines such as
The pyrido[2,3-d]pyrimidine nucleus represents in many bio-
logically active compounds which includes antitumour [1], anti-
bacterial [2], anticonvulsant [3], antipyretic [4], analgesic [5], and
CNS depressant activity [6]. Specifically pyrido[2,3-d]pyrimidines
known to inhibit Pneumocystis carinii(pc), Toxoplasma gondii(tg)
of tumour cell lines in culture [7] and the activity is attributed to
inhibition of dihydrofolate reductase (DHFR) [8,9]. In recent past it
was found that the fluorine [10] or trifluoromethyl [11,12] group at
a strategic position of an organic molecule dramatically alters the
properties of molecule in terms of lipid solubility, oxidative thermal
stability, permeability, oral bioavailability thereby enhancement of
transport mechanism.
The perfluoroalkyl triazoles [13,14] perfluoroalkyl tetrazole [15]
and other fluoroalkyl derivatives [16e18] also found to show prom-
ising biological activity. Based on the importance and further to our
ongoing research on the synthesis of hetero ring fused pyridines as
potential molecules [19e21], we commenced our synthetic strategy
towards a series of novel pyrido[2,3-d]pyrimidines, N-/O-propargyl
U937, THP-1and Colo205. The promising compounds 5b, 5ehave been
identified and reporting here for the first time.
2. Chemistry
The 2-amino-3-cyano-4-trifluoromethyl-6-phenyl pyridine 1
[22] was reacted with various aliphatic acids in presence of catalytic
amount of sulphuric acid at 120e130 ꢀC for 12e20 h, obtained
pyrido[2,3-d]pyrimidine derivatives 2. The reaction sequence
involves acylation of amine, hydrolysis of nitrile to amide followed
by cyclization and dehydration to form products 2 in single step.
However, reaction with aromatic acids under same conditions
could not drive the reaction to the products. Alternatively
compound 1 was reacted with benzaldehyde followed by MnO2
oxidation resulted 2-phenyl pyrido[2,3-d]pyrimidine [23]. Efforts
to introduce CF3 or perfluoroalkyl group in second position of
pyrido[2,3-d]pyrimidine under different set of conditions such as
(i) CF3COOH, conc. H2SO4, reflux, 14e16 h (ii) (CF3CO)2O, PTSA,
reflux, 14e16 h (iii) CF3COOC2H5, conc. H2SO4, reflux, 20 h. (iv)
CF3CF2eCOOH, PTSA, 100 ꢀC, 15e16 h (v) CF3COOH þ (CF3CO)2O,
PTSA, 60e70 ꢀC, 15e16 h (vi) CF3CF2eCOOH, conc. H2SO4, sealed
tube, 120 ꢀC, 10e12 h (vii) (CF3CO)2O, conc. H2SO4, 100 ꢀC, sealed
* Corresponding author. Tel.: þ91 40 27193630; fax: þ91 40 27160387.
E-mail address: narsaiah_1984@yahoo.co.in (B. Narsaiah).
0223-5234/$ e see front matter Ó 2011 Elsevier Masson SAS. All rights reserved.
doi:10.1016/j.ejmech.2011.05.011

C. Kurumurthy et al. / European Journal of Medicinal Chemistry 46 (2011) 3462e3468
3463
R'
N
CF3
CF3
N
O
N
CN
Conc.H2SO4
120-130oc
12-18hrs
N
CF3
R-COOH
O
N
CF3
N
NH
O
N
N
Ph
N
NH2
DryTHF
N
N
Ph
R
R'-N3
CuI,
r.t
Ph
N
R
24hrs
Ph
R
1
2
3
5
R = H, CH3, C2H5, (CH3)2CH-, Ph, CH3-(CH2)4-CH2-
5a) R = H, R’= C8F17-CH2-CH2-, 5b) R = H, R’= CH3-(CH2)8-CH2-
CF3
N
CF3
O
CF3
O
N
O
N
5c) R = CH3, R’ = C6F13-CH2-CH2, 5d) R = CH3, R’ = C8F17-CH2-CH2-
5e) R = CH3, R’= CH3-(CH2)8-CH2-, 5f) R = CH3, R’= Ph-
N
N
Acetone
NH
Br
K2CO3, NaI
Ph
R
N
R
Ph
N
Ph
N
R
60oc
5g) R = C2H5, R’ = C6F13-CH2-CH2, 5h) R = C2H5, R’ = C8F17-CH2-CH2-
4-5hrs,
5i) R = C2H5, R’= CH3-(CH2)8-CH2-, 5j) R = (CH3) 2 CH-, R’= C8F17-CH2-CH2-
5k) R = CH3-(CH2)4-CH2-, R’ = C6F13-CH2-CH2-, 5l) R = CH3-(CH2)4-CH2-,
R’ = C8F17-CH2-CH2
2
3
4
3
:
:
1
1
3 if R = Ph
Scheme 2. Synthesis of N-alkyltriazole tagged pyrido[2,3-d]pyrimidine derivatives
(5ae5l).
R = H, CH3, C2H5, (CH3)2CH-, Ph, CH3-(CH2)4-CH2-
The reaction is considered to take place via 1,3-dipolar cycloaddition
of perfluoroalkyl azide to alkyne through a preformed copper ace-
tylide complex formation under sharpless conditions [25,26]. The
product yields were tabulated in Table 2.
Scheme 1. Synthesis of 2-substituted-5-trifluoromethyl-7-phenyl pyrido[2,3-d]
pyrimidine-4(3H)-ones (2aef) and N-/O-propargyl-2-substituted-5-trifluoromethyl-7-
phenyl pyrido[2,3-d]pyrimidine-4(3H)-ones (3aef)/pyrido[2,3-d]pyrimidines (4aef).
tube, 10e12 h could not give the product and recovered the starting
material. Compound 2 when R ¼ alkyl was further reacted with
propargyl bromide in acetone using potassium carbonate as a base,
obtained two regioisomers 3 and 4 (N-propargylated and O-prop-
argylated) in definite proportion of 3:1 ratio. If R ¼ aryl, the ratio is
reversed to 1:3 and is attributed to steric hindrance as a result
O-propargylated product as major. The ratio of products was
established based on 1H NMR data in which the signal for NeCH2
3. Results and discussion
The compounds 5ael and 6aec were screened in vitro against
three cancer cell lines such as U937 (human leukemic monocytic
lymphoma), THP-1 (human acute monocytic leukemia) and Colo205
(human colourectal cancer) using MTTassay method [27]. IC50 values
of the test compound for 24 h on each cell line was calculated and
presentedin a Table 3. Compound 5band 5eexhibited decrease in cell
viabilityinallthethreetestcelllines,howevercompound5i, 5jand6a
are active only on U937 and THP-1 cells. Similarly compound 5k show
activity against U937 and Colo205 cell lines and compound 5a show
against THP-1 and Colo205. Other compounds such as 5d, 6b and 6c
showactivityonlyonU937 celllines. Theorderof toxicityover U937 cell
linesis5e>5k>5b>5j>6b>Etoposide. Structureactivityrelationship
studies revealed that the presence of hydrogen or methyl group in
second position and alkyltriazole tag in 3rd position promote high
activity as experienced in compound 5b, 5e and is better than stan-
dard Etoposide against U937 cell lines. Among all the compounds,
compound 5e with methyl in 2nd position and alkyl tag in 3rd posi-
tion found to show high activity. However, perfluoroalkyl tag on tri-
azole is considered to be detrimental to the activity. Increase in
aliphatic chain length on 2nd position has no additional advantage in
promoting activity. Thus, promising compounds 5b and 5e will be
further optimized in order to find a potential candidate for further
evaluation. The activity data is tabulated in Table 3.
appeared in the range
OeCH2 appeared in the range
d
4.71 ppme4.97 ppm, whereas signal for
5.25 ppm to 5.44 ppm. The intensity
d
of each signal is considered for estimating the ratio of each
compound. The synthetic sequence is drawn in a Scheme 1 and
products are tabulated in Table 1.
The two regioisomers such as N- and O-propargylated pyrido
[2,3-d]pyrimidines 3 and 4 were separated based on their differ-
ence in polarity and each isomer was independently reacted with
alkyl or perfluoroalkyl azide in THF, using copper(I) iodide as catalyst
[24] and resulted exclusively 1,4-disubstituted-1,2,3-triazole deriv-
atives 5 and 6 respectively as outlined in Schemes 2 and 3.
Table 1
Preparation of pyrido[2,3-d]pyrimidine derivatives 2aef, 3aef, and 4aef.
Compound no.
R
m. pt. ꢀC
Yield (%)
2a
2b
2c
2d
2e
2f
3a
4a
3b
4b
3c
4c
3d
4d
3e
4e
3f
H
CH3
C2H5
(CH3)2CH
CH3-(CH2)4-CH2
C6H5
H
H
CH3
CH3
C2H5
C2H5
(CH3)2CH
(CH3)2CH
CH3-(CH2)4-CH2
CH3-(CH2)4-CH2
C6H5
245e248
291e292
272e274
283e286
233e235
309e311
220e223
204e206
212e214
208e211
205e207
199e202
168e170
248e250
167e168
150e152
203e205
227e229
78
90
93
95
96
72
73.5
24.5
72.6
24.2
72
R'
N
CF3
N
CF3
O
N
O
N
N
N
DryTHF
r.t
N
N
R'-N3
CuI,
24hrs
Ph
N
R
Ph
R
4
6
24
71.4
23.8
70.5
23.5
24.38
73.14
6a) R = CH3, R’= C8F17-CH2-CH2-, 6b) R = C2H5, R’= C6F13-CH2-CH2-
6c) R = Ph, R’ = C8F17-CH2-CH2, 6d) R = (CH3) 2 CH-, R’ = C6F13-CH2-CH2-
4f
C6H5
Scheme 3. Synthesis of O-alkyltriazole tagged pyrido[2,3-d]pyrimidine derivatives
(6ae6d).
*All are new compounds except 2f[23].

3464
C. Kurumurthy et al. / European Journal of Medicinal Chemistry 46 (2011) 3462e3468
Table 2
5.1. Preparation of 2-substituted-5-trifluoromethyl-7-phenyl pyrido
[2,3-d]pyrimidin-4(3H)-ones (2aef)
Preparation of N-/O-alkyltriazole tagged pyrido[2,3-d]pyrimidine derivatives.
Compound no.
R
R0
m. pt. ꢀC
Yield (%)
5.1.1. General procedure
5a
5b
5c
5d
5e
5f
5g
5h
5i
5j
5k
5l
6a
6b
6c
6d
H
H
CH3
CH3
CH3
CH3
C2H5
C2H5
C8F17CH2-CH2
CH3(CH2)8-CH2
C6F13CH2-CH2
C8F17CH2-CH2
CH3(CH2)8-CH2
C6H5
C6F13CH2-CH2
C8F17CH2-CH2
CH3(CH2)8-CH2
C8F17CH2-CH2
C6F13CH2-CH2
C8F17CH2-CH2
C8F17CH2-CH2
C6F13CH2-CH2
C8F17CH2-CH2
C6F13CH2-CH2
180e182
143e144
209e212
203e206
123e124
215e217
141e144
182e185
145e147
186e188
149e151
147e148
156e159
124e126
290e293
173e175
95
92
90
89
95
96
86
90
93
91
89
87
85
88
89
86
A
mixture of 2-amino-3-cyano-4-trifluoromethyl-6-phenyl
pyridine (1) (1.9 mmol), aliphatic acids (5 ml) and a catalytic
amount of conc. sulphuric acid was heated at 120e130 ꢀC for
12e20 h. The reaction mixture was allowed to cool to room
temperature, poured into ice cold water. The separated solid was
collected by filtration, dried and recrystallized from ethanol.
C2H5
(CH3)2CH
CH3-(CH2)4-CH2
CH3-(CH2)4-CH2
CH3
C2H5
C6H5
5.1.1.1. 7-Phenyl-5-(trifluoromethyl) pyrido[2,3-d]pyrimidine-4(3H)-
one(2a). IR (KBr, cmꢁ1): 3180 (-NH-),1679 (lactam CO),1344 (-C-F);
1H NMR (DMSO, 300 MHz):
d 7.53e7.57 (m, 3H, Ar-H), 7.98 (s, 1H,
Py-HC(2) ), 8.20e8.29 (m, 3H, Ar-H), 12.72 (br, s, -NH-); MS (EI,
70 eV): m/z(%) Mþ, 291(100), 263(40) (Mþ-28), 222(25) (Mþ-69);
Anal. Calcd. for C14H8F3N3O: C 57.74, H 2.77, N 14.43%. Found: C
57.68, H 2.72, N 14.41%.
(CH3)2CH
4. Conclusion
5.1.1.2. 2-Methyl-7-phenyl-5-(trifluoromethyl)
imidin-4(3H)-one(2b). IR (KBr, cmꢁ1): 3188 (-NH-), 1688 (lactam
CO), 1372 (-C-F); 1H NMR (DMSO, 300 MHz):
2.51 (s, 3H, eCH3),
7.50e7.55 (m, 3H, Ar-H), 8.10 (s, 1H, Py-HC(6)), 8.21e8.25 (m, 2H,
Ar-H), 12.68 (br, s, -NH-); MS (EI, 70eV): m/z(%) Mþ, 305(100),
277(25) (Mþ-28), 236(40) (Mþ-69); Anal. Calcd. for C15H10F3N3O: C
59.02, H 3.30, N 13.77%. Found: C 58.98, H 3.27, N 13.73%.
pyrido[2,3-d]pyr-
A series of novel pyrido[2,3-d]pyrimidine derivatives 2 were
prepared by an efficient route and subjected to alkylation to obtain
two regioisomers 3 and 4 in definite proportion. Each regioisomer
was separated based on their difference in polarity and cyclised
with various azides to obtain alkyltriazole tagged final products 5
and 6. The products 5 and 6 were screened for anticancer activity
and promising compounds 5b and 5e have been identified.
d
5.1.1.3. 2-Ethyl-7-phenyl-5-(trifluoromethyl) pyrido[2,3-d]pyrimidin-
4(3H)-one(2c). IR (KBr, cmꢁ1): 3186 (-NH-), 1690 (lactam CO), 1370
5. Experimental
(-C-F); 1H NMR (DMSO, 300 MHz):
d
1.30 (t, 3H, J ¼ 7.55 Hz, -CH3),
2.71 (q, 2H, J ¼ 7.55 Hz, -CH2-), 7.58e7.61 (m, 3H, Ar-H), 8.28e8.33
(m, 3H, Ar-H), 12.65 (br, s, -NH-); MS (EI, 70 eV): m/z(%) Mþ,
319(100), 291(15) (Mþ-28), 250(40) (Mþ-69); Anal. Calcd. for
C16H12F3N3O: C 60.19, H 3.79, N 13.16%. Found: C 60.20, H 3.77, N
13.17%.
Melting points of all the compounds was recorded on
CasiaeSiamia (VMP-AM) melting point apparatus and are uncor-
rected. IR spectra were recorded on a PerkineElmer FT-IR 240-C
spectrophotometer using KBr optics. 1H NMR spectra were recor-
ded on Bruker AV 300 MHz and INOVA 400 MHz in DMSO-d6 or
CDCl3 using TMS as internal standard. Electron impact (EI) and
chemical ionization mass spectra were recorded on a VG 7070 H
instrument at 70 eV. All high-resolution spectra were recorded on
QSTARXL hybrid MS/MS system (Applied Biosystems, USA) under
electrospray ionization. All the reactions were monitored by thin
layer chromatography (TLC) on precoated silica gel 60 F254 (mesh);
spots were visualized with UV light. Merck silica gel (60e120 mesh)
was used for column chromatography. CHN analyses were recorded
on a vario EL analyzer.
5.1.1.4. 2-Isopropyl-7-phenyl-5-(trifluoromethyl)
pyrido[2,3-d]pyr-
imidin-4(3H)-one(2d). IR (KBr, cmꢁ1): 3187 (-NH-),1677 (lactam CO),
1591 (-C¼N), 1368 (-C-F); 1H NMR (DMSO, 400 MHz):
d 1.36 (d, 6H,
J ¼ 7.168Hz, (-CH3)2), 2.99 (m,1H, -CH-), 7.53e7.57 (m, 3H, Ar-H), 8.14
(s, 1H, Py-HC(6)), 8.23e8.28 (m, 2H, Ar-H), 12.57 (br, s, -NH-); MS (EI,
70 eV): m/z(%) Mþ, 333(45), 318(100) (Mþ-15), 305(20) (Mþ-28),
264(15) (Mþ-69); Anal. Calcd. for C17H14F3N3O: C 61.26, H 4.23, N
12.61%. Found: C 61.20, H 4.19, N 12.59%.
5.1.1.5. 2-n-Hexyl-7-phenyl-5-(trifluoromethyl)
pyrido[2,3-d]pyr-
Table 3
imidin-4(3H)-one(2e). IR (KBr, cmꢁ1): 3184 (-NH-), 1683 (lactam
In vitro cytotoxicity of pyrido[2,3-d]pyrimidine derivatives against U937, THP-1 and
Colo205 cancer cell lines.
CO), 1591 (-C¼N), 1368 (-C-F); 1H NMR (DMSO, 300 MHz):
d 0.91 (t,
3H,
J
¼
6.798Hz, -CH3), 1.30e1.44 (m, 6H, -CH2-CH2-CH2-),
Compound no.
IC50 (mg/ml)
1.79e1.88 (m, 2H, -CH2-), 2.71 (t, 2H, J ¼ 7.554Hz -CH2-), 7.50e7.54
(m, 3H, Ar-H), 8.10 (s, 1H, Py-HC(6)), 8.21e8.26 (m, 2H, Ar-H), 12.60
(br, s, -NH-); MS (EI, 70 eV): m/z(%) Mþ, 375(20), 360(10) (Mþ-15),
346(25) (Mþ-29), 305(100) (Mþ-70); Anal. Calcd. for C20H20F3N3O:
C 63.99, H 5.37, N 11.19%. Found: C 64.01, H 5.29, N 11.21%.
U937
THP-1
79.12 ꢂ 2.41 162.52 ꢂ 5.62
16.91 ꢂ 1.42 19.25 ꢂ 1.46
Colo205
5a
5b
5c
5d
5e
5f
5g
5h
e
8.16 ꢂ 0.68
e
e
e
124.23 ꢂ 3.67
e
e
6.20 ꢂ 0.68
11.27 ꢂ 1.67
15.01 ꢂ 1.54
2,7-Diphenyl-5-(trifluoromethyl)
4(3H)-one(2f)[23].
pyrido[2,3-d]pyrimidine-
e
e
e
e
e
e
e
e
e
5i
5j
5k
5l
17.83 ꢂ 1.35
82.65 ꢂ 3.41
e
5.2. Preparation of N-/O-propargyl-2-substituted-5-trifluoromethyl-
7-phenyl pyrido[2,3-d]pyrimidine-4(3H)-ones (3aef/pyrido[2,3-d]
pyrimidines (4aef)
8.35 ꢂ 0.34 142.23 ꢂ 5.24
e
7.56 ꢂ 0.74
e
e
132.42 ꢂ 4.26
e
e
6a
6b
6c
22.37 ꢂ 1.73
9.22 ꢂ 0.76
44.35 ꢂ 2.14
17.94 ꢂ 1.19
107 ꢂ 4.62
2.16 ꢂ 0.15
e
5.2.1. General procedure
e
e
e
e
Quinazol-4-one 2 (0.65 mmol) was dissolved in acetone (10 ml),
K2CO3 (1.3 mmol), NaI (2 mg) was added. The propargyl bromide
(1.9 mmol) was slowly added drop wise to the above mixture over
Etoposide (positive control)
7.24 ꢂ 1.26
eindicated IC50 values are more than 200 mg/ml.

C. Kurumurthy et al. / European Journal of Medicinal Chemistry 46 (2011) 3462e3468
3465
a period of 15 min at room temperature. Reaction mixture was
refluxed for 3e4hrs and solvent was removed under reduced
pressure. The residue was washed with n-hexane repeatedly to
remove excess propargyl bromide, treated with distilled water to
remove excess potassium carbonate and solid product separated
was filtered, purified by eluting through column using 12% ethyl
acetate in n-hexane for N-propargylated compound 3 and 30% ethyl
acetate in n-hexane for O-propargylated compound 4.
405(100), 336(10) (Mþ-69); Anal. Calcd. for C23H14F3N3O: C 68.15, H
3.48, N 10.37%. Found: C 68.18, H 3.42, N 10.32%.
5.2.1.7. 7-Phenyl-4-(prop-2-ynyloxy)-5-(trifluoromethyl) pyrido[2,3-
d]pyrimidine(4a). IR (KBr, cmꢁ1): 2116 (-ChC-), 1658 (-C¼N), 1371
(-C-F), 1272 (C-O-C); 1H NMR (CDCl3, 400 MHz):
d 2.55 (s, 1H,
-ChCH), 5.25 (s, 2H, -CH2-O-), 7.55e7.57 (m, 3H, Ar-H), 8.20e8.22
(m, 3H, Ar-H), 8.72 (s, 1H, Py-HC(2)), MS (EI, 70 eV): m/z(%) Mþ,
329(15), 301(20) (Mþ-28),149(100); Anal. Calcd. for C17H10F3N3O: C
62.01, H 3.06, N 12.76%. Found: C 61.98, H 3.04, N 12.72%.
5.2.1.1. 7-Phenyl-3-(prop-2-ynyl)-5-(trifluoromethyl) pyrido[2,3-d]
pyrimidine-4(3H)-one(3a). IR (KBr, cmꢁ1): 2117 (-ChC-), 1696
(lactam CO), 1594 (-C¼N), 1368 (-C-F); 1H NMR (CDCl3, 300 MHz):
5.2.1.8. 2-Methyl-7-phenyl-4-(prop-2-ynyloxy)-5-(trifluoromethyl)
pyrido[2,3-d]pyrimidine(4b). IR (KBr, cmꢁ1): 2127 (-ChC-), 1667
d
2.57 (t, 1H, J ¼ 2.45 Hz, -ChCH), 4.84 (d, 2H, J ¼ 2.45 Hz, -CH2-N-),
7.52e7.55 (m, 3H, Ar-H), 8.21e8.26 (m, 3H, Ar-H), 8.63 (s, 1H, Py-
HC(2)), MS (EI, 70eV): m/z(%) Mþ, 329(100), 301(15) (Mþ-28);
Anal. Calcd. for C17H10F3N3O: C 62.01, H 3.06, N 12.76%. Found: C
61.91, H 3.02, N 12.69%.
(-C¼N), 1373 (-C-F),1262 (C-O-C); 1H NMR (CDCl3, 300 MHz):
d 2.51
(s, 1H, -ChCH), 3.13 (s, 3H, -CH3), 5.44 (s, 2H, -CH2-O-), 7.49e7.54
(m, 3H, Ar-H), 8.13 (s, 1H, Py-HC(6)), 8.20e8.26 (m, 2H, Ar-H), MS
(EI, 70eV): m/z(%) (Mþ-H), 342(29), 301(100) (Mþ-41), 273(38)
(Mþ-69); Anal. Calcd. for C18H12F3N3O: C 62.97, H 3.52, N 12.24%.
Found: C 62.99, H 3.50, N 12.23%.
5.2.1.2. 2-Methyl-7-phenyl-3-(prop-2-ynyl)-5-(trifluoromethyl) pyr-
ido[2,3-d]pyrimidine-4(3H)-one(3b). IR (KBr, cmꢁ1): 2118 (-ChC-),
1696 (lactam CO), 1593 (-C¼N), 1368 (-C-F); 1H NMR (CDCl3,
5.2.1.9. 2-Ethyl-7-phenyl-4-(prop-2-ynyloxy)-5-(trifluoromethyl)
pyrido[2,3-d]pyrimidine(4c). IR (KBr, cmꢁ1): 2128 (-ChC-), 1664
300 MHz):
d
2.32 (t, 1H, J ¼ 2.45 Hz, -ChCH), 2.88 (s, 3H, -CH3), 4.93
(d, 2H, J ¼ 2.45 Hz, -CH2-N-), 7.51e7.53 (m, 3H, Ar-H), 8.15 (s,1H, Py-
HC(6)), 8.21e8.24 (m, 2H, Ar-H), MS (EI, 70 eV): m/z(%) Mþ,
343(100), 315(20) (Mþ-28), 274(28) (Mþ-69); Anal. Calcd. for
C18H12F3N3O: C 62.97, H 3.52, N 12.24%. Found: C 63.01, H 3.49, N
12.26%.
(-C¼N),1378 (-C-F),1260 (C-O-C); 1H NMR (CDCl3, 400 MHz):
d 1.43 (t,
3H, J ¼ 7.22 Hz, -CH3), 2.54 (t, 1H, J ¼ 2.71 Hz, -ChCH), 3.08 (q, 2H,
J¼7.22 Hz, -CH2-), 5.37 (d, 2H, J ¼ 2.71 Hz, -CH2-O-), 7.55e7.58 (m, 3H,
Ar-H), 8.19e8.23 (m, 3H, Ar-H), MS (EI, 70 eV): m/z(%) (Mþ-H), 356(33),
301(100) (Mþ-55), 273(32) (Mþ-83); Anal. Calcd. for C19H14F3N3O: C
63.86, H 3.95, N 11.76%. Found: C 63.83, H 3.98, N 11.73%.
5.2.1.3. 2-Ethyl-7-phenyl-3-(prop-2-ynyl)-5-(trifluoromethyl) pyrido
[2,3-d]pyrimidine-4(3H)-one(3c). IR (KBr, cmꢁ1): 2126 (-ChC-),
1687 (lactam CO), 1595 (-C¼N), 1371 (-C-F); 1H NMR (CDCl3,
5.2.1.10. 2-Isopropyl-7-phenyl-4-(prop-2-ynyloxy)-5-(trifluoromethyl)
pyrido[2,3-d]pyrimidine(4d). IR (KBr, cmꢁ1): 2117 (-ChC-), 1664
300 MHz):
d
1.55 (t, 3H, J ¼ 7.55 Hz, -CH3), 2.30 (t, 1H, J ¼ 2.26 Hz,
(-C¼N), 1372 (-C-F), 1258 (C-O-C); 1H NMR (CDCl3, 300 MHz):
d 1.47
-ChCH), 3.11 (q, 2H, J ¼ 7.55 Hz, -CH2-), 4.94 (d, 2H, J ¼ 2.26 Hz,
-CH2-N-), 7.51e7.55 (m, 3H, Ar-H), 8.14 (s, 1H, Py-HC(6)), 8.20e8.25
(m, 2H, Ar-H), MS (EI, 70eV): m/z(%) Mþ, 357(100), 329(23) (Mþ-
28), 288(10) (Mþ-69); Anal. Calcd. for C19H14F3N3O: C 63.86, H 3.95,
N 11.76%. Found: C 63.81, H 4.01, N 11.71%.
(d, 6H, J ¼ 6.79 Hz, (-CH3)2), 2.34 (t, 1H, J ¼ 2.26 Hz, -ChCH), 3.39 (m,
1H, -CH-), 5.34 (d, 2H, J ¼ 2.26 Hz, -CH2-O-), 7.54e7.57 (m, 3H, Ar-H),
8.11e8.15 (m, 3H, Ar-H); MS (EI, 70 eV): m/z(%) (Mþ-H), 370(22),
356(68) (Mþ-14), 301(100) (Mþ-69); Anal. Calcd. for C20H16F3N3O: C
64.69, H 4.34, N 11.32%. Found: C 64.67, H 4.32, N 11.30%.
5.2.1.4. 2-Isopropyl-7-phenyl-3-(prop-2-ynyl)-5-(trifluoromethyl)
pyrido[2,3-d]pyrimidine-4(3H)one(3d). IR (KBr, cmꢁ1): 2127 (-ChC-),
1698 (lactam CO), 1590 (-C¼N), 1371 (-C-F); 1H NMR (CDCl3,
5.2.1.11. 2-n-Hexyl-7-phenyl-4-(prop-2-ynyloxy)-5-(trifluoromethyl)
pyrido[2,3-d] pyrimidine(4e). IR (KBr, cmꢁ1): 2128 (-ChC-), 1665
(-C¼N),1367 (-C-F),1267 (C-O-C); 1H NMR (CDCl3, 400 MHz):
d 0.92
300 MHz):
d
1.52 (d, 6H, J ¼ 6.04 Hz, (-CH3)2), 2.31 (t, 1H, J ¼ 2.26 Hz,
(t, 3H, J ¼ 6.59Hz, -CH3), 1.34e1.53 (m, 6H, -CH2-CH2-CH2-), 1.94
(pentet, 2H, J ¼ 7.32 Hz,-CH2), 2.34 (s, 1H, -ChCH), 2.95 (t, 2H,
J ¼ 7.32 Hz,-CH2), 5.29 (s, 2H, -CH2-O-), 7.53e7.58 (m, 3H, Ar-H),
8.11e8.15 (m, 3H, Ar-H); MS (EI, 70 eV): m/z(%) (Mþ-H), 412(12),
342(100) (Mþ-70); Anal. Calcd. for C23H22F3N3O: C 66.82, H 5.36, N
10.16%. Found: C 66.79, H 5.37, N 10.14%.
-ChCH), 3.44 (m, 1H, -CH-), 4.97 (d, 2H, J ¼ 2.26 Hz, -CH2-N-),
7.50e7.53 (m, 3H, Ar-H), 8.12 (s, 1H, Py-HC(6)), 8.19e8.23 (m, 2H, Ar-
H), MS (EI, 70eV): m/z(%) Mþ, 371(48), 356(100) (Mþ-15); Anal.
Calcd. for C20H16F3N3O: C 64.69, H 4.34, N 11.32%. Found: C 64.70, H
4.31, N 11.29%.
5.2.1.5. 2-n-Hexyl-7-phenyl-3-(prop-2-ynyl)-5-(trifluoromethyl) pyr-
ido[2,3-d]pyrimidine-4(3H)-one(3e). IR (KBr, cmꢁ1): 2113 (-ChC-),
1701 (lactam CO), 1593 (-C¼N), 1370 (-C-F); 1H NMR (CDCl3,
5.2.1.12. 2,7-Diphenyl -4-(prop-2-ynyloxy)-5-(trifluoromethyl) pyr-
ido[2,3-d]pyrimidine(4f). IR (KBr, cmꢁ1): 2124 (-ChC-), 1577
(-C¼N), 1321 (-C-F); 1258 (C-O-C); 1H NMR (CDCl3, 300 MHz):
300 MHz):
d
0.93 (t, 3H, J ¼ 6.79 Hz, -CH3), 1.36e1.42 (m, 4H, -CH2-
d
2.52 (t, 1H, J ¼ 2.26 Hz, -ChCH), 5.39 (d, 2H, J ¼ 2.26 Hz, -CH2-O-),
CH2-), 1.49e1.57 (m, 2H, -CH2-), 1.99 (pentet, 2H, J ¼ 8.31 Hz, -CH2-),
2.31 (t,1H, J ¼ 2.26 Hz, -ChCH), 3.04 (t, 2H, J ¼ 8.31 Hz, -CH2-), 4.93 (d,
2H, J ¼ 2.26 Hz, -CH2-N-), 7.50e7.54 (m, 3H, Ar-H), 8.14 (s, 1H, Py-
HC(6)), 8.20e8.25 (m, 2H, Ar-H), MS (EI, 70 eV): m/z(%) Mþ, 413(10),
342(100) (Mþ-71); Anal. Calcd. for C23H22F3N3O: C 66.82, H 5.36, N
10.16%. Found: C 66.79, H 5.32, N 10.13%.
7.51e7.58 (m, 6H, Ar-H), 8.26e8.34 (m, 3H, Ar-H), 8.67e8.72 (m, 2H,
Ar-H), MS (EI, 70 eV): m/z(%) (Mþ-H), 404(100), 368(12); Anal.
Calcd. for C23H14F3N3O: C 68.15, H 3.48, N 10.37%. Found: C 68.16, H
3.45, N 10.35%.
5.3. Preparation of N-/O-alkyltriazole-5-trifluoromethyl-7-phenyl
pyrido[2,3-d]pyrimidin-4(3H)-ones (5a-l/pyrido[2,3-d]pyrimidines
(6aed)
5.2.1.6. 2,7-Diphenyl-3-(prop-2-ynyl)-5-(trifluoromethyl)
pyrido
[2,3-d]pyrimidine-4(3H)-one(3f). IR (KBr, cmꢁ1): 2117 (-ChC-),
1685 (lactam CO), 1583 (-C¼N), 1372 (-C-F); 1H NMR (CDCl3,
5.3.1. General procedure
300 MHz):
d
2.34 (t, 1H, J ¼ 2.26 Hz, -ChCH), 4.71 (d, 2H,
The propargylated quinazoline 3 or 4 (0.36 mmol) was dissolved
in dry THF (5 ml) and catalytic amount of CuI was added. Then
alkyl/perfluoroalkyl/aryl azides in dry THF was slowly added at
J ¼ 2.26 Hz, -CH2-N-), 7.50e7.58 (m, 6H, Ar-H), 7.82e7.86 (m, 2H,
Ar-H), 8.20e8.27 (m, 3H, Ar-H); MS (EI, 70 eV): m/z(%) Mþ,

3466
C. Kurumurthy et al. / European Journal of Medicinal Chemistry 46 (2011) 3462e3468
room temperature under nitrogen atmosphere and continued
stirring for 24 h. The solvent was removed under reduced pressure,
the residue was diluted with distilled water and extracted twice
with ethyl acetate. The combined organic layer was dried over
anhydrous Na2SO4 and concentrated to get the product. The crude
product was purified by column chromatography.
(nm): 334, 256; 1H NMR (CDCl3, 300 MHz):
d 3.13 (s, 3H, -CH3), 5.44
(s, 2H, -CH2-N-), 7.42 (m, 1H, Ar-H), 7.48e7.54 (m, 5H, Ar-H), 7.73 (d,
2H, J ¼ 7.74 Hz, Ar-H), 8.14 (s, 1H, Py-HC(6)), 8.20e8.26 (m, 3H, Ar-H);
13C NMR (CDCl3, 75 MHz):
d 23.91, 40.11, 109.68, 116.79, 120.49,
122.54, 127.92, 128.94, 129.70, 131.35, 136.47, 136.67, 142.57, 159.19,
159.71, 163.45; HRMS m/z Calcd. for C24H18F3N6O ([M þ H]þ):
463.1494, Found 463.1496.
5.3.1.1. 3-((1-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorodecyl)-
1H-1,2,3-triazol-4-yl)methyl)-7-phenyl-5-(trifluoromethyl) pyrido[2,3-
d]pyrimidine-4(3H)-one(5a). IR (KBr, cmꢁ1): 1696 (lactam CO), 1599
(-C¼N), 1369 (-C-F); UV lmax (nm): 334, 258; 1H NMR (CDCl3,
5.3.1.7. 2-Ethyl-7-phenyl-3-((1-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-
octyl)-1H-1,2,3-triazol-4-yl)methyl)- 5-(trifluoromethyl) pyrido[2,3-d]
pyrimidin-4(3H)-one(5g). IR (KBr, cmꢁ1): 1690 (lactam CO), 1596
(-C¼N), 1373 (-C-F); UV lmax (nm): 335, 258; 1H NMR (CDCl3,
400 MHz):
d
2.76e2.87 (m, 2H, -CH2-CF2), 4.66 (t, 2H, J ¼ 6.83 Hz,
-CH2-), 5.27 (s, 2H, -CH2-N-), 7.51e7.54 (m, 3H, Ar-H), 7.88 (s, 1H,
400 MHz):
d
1.56 (t, 3H, J ¼ 7.36Hz, -CH3), 2.73e2.90 (m, 2H, -CH2-CF2),
Triazol-H), 8.18e8.24 (m, 2H, Ar-H), 8.67 (s, 1H, Py-HC(2)); 13C NMR
3.36 (q, 2H, J ¼ 7.36Hz, -CH2-), 4.65 (t, 2H, J ¼ 7.74 Hz, -CH2-N-), 5.36 (s,
(CDCl3, 75 MHz):
d 31.67, 42.09, 42.53, 117.44, 117.53, 120.29, 122.13,
2H, -CH2-N-), 7.50e7.53(m, 3H, Ar-H), 7.87(s,1H, Triazol-H), 8.12 (s,1H,
124.62, 124.70, 127.96, 129.11, 131.58, 136.32, 139.17, 141.70, 150.19,
150.46, 163.17, 163.30, 163.52; HRMS m/z Calcd. for C27H14F20N6ONa
([M þ Na]þ): 841.0807, Found 841.0835.
Py-HC(6)), 8.19e8.23 (m, 2H, Ar-H); 13C NMR (CDCl3, 75 MHz):
d 11.26,
28.90, 31.63, 39.27, 42.38, 109.62,116.90, 124.95, 127.99,128.94, 131.29,
136.63,138.38,138.89,142.53,159.35,159.43,163.13,163.65; HRMS m/z
Calcd. for C27H18F16N6ONa ([M þ Na]þ): 769.1184, Found 769.1176.
5.3.1.2. 3-((1-Decyl-1H-1,2,3-triazol-4-yl)methyl)-7-phenyl-5-(tri-
fluoromethyl)
pyrido[2,3-d]pyrimidine-4(3H)-one(5b). IR
(KBr,
5.3.1.8. 2-Ethyl-3-((1-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecaflu-
orodecyl)-1H-1,2,3-triazol-4-yl)methyl)- 7-phenyl-5-(trifluoromethyl)
pyrido[2,3-d]pyrimidin-4(3H)-one(5h). IR (KBr, cmꢁ1): 1691 (lactam
CO),1592 (-C¼N),1369 (-C-F); UV lmax (nm): 334, 258;1HNMR(CDCl3,
cmꢁ1): 1690(lactam CO),1594 (-C¼N),1366 (-C-F); UV lmax (nm): 334,
258; 1H NMR (CDCl3, 300 MHz):
d
0.87 (t, 3H, J ¼ 6.79 Hz, -CH3),
1.21e1.33 (m,16H, -(CH2)7-),1.89(m, 2H, -CH2-), 4.32 (t, 2H, J¼ 7.55 Hz,
-CH2-N-), 5.27 (s, 2H, -CH2-N-), 7.50e7.55 (m, 3H, Ar-H), 7.76 (s, 1H,
Triazol-H), 8.17e8.25 (m, 3H, Ar-H), 8.70 (s, 1H, Py-HC(2)); HRMS m/z
Calcd. for C27H31F3 N6ONa ([M þ Na]þ): 535.2409, Found 535.2412.
300 MHz):
d
1.56 (t, 3H, J ¼ 7.17 Hz, -CH3), 2.81 (m, 2H, -CH2-CF2), 3.36
(q, 2H, J ¼ 7.17 Hz, -CH2-), 4.65 (t, 2H, J ¼ 7.17 Hz, -CH2-N), 5.35 (s, 2H,
-CH2-N-), 7.48e7.53 (m, 3H, Ar-H), 7.87 (s, 1H, Triazol-H), 8.11 (s, 1H,
Py-HC(6)), 8.18e8.24 (m, 2H, Ar-H); 13C NMR (CDCl3, 75 MHz):
d 11.29,
5.3.1.3. 2-Methyl-7-phenyl-3-((1-(3,3,4,4,5,5,6,6,7,7,8,8,8-trideca-
fluorooctyl)-1H-1,2,3-triazol-4-yl)methyl)-5-(trifluoromethyl) pyrido
[2,3-d]pyrimidine-4(3H)-one(5c). IR (KBr, cmꢁ1): 1694 (lactam CO),
1592 (-C¼N), 1368 (-C-F); UV lmax (nm): 334, 258; 1H NMR (CDCl3,
28.94, 31.68, 39.30,42.40,109.65,116.94,124.96,128.02,128.96,131.32,
136.67,138.41,138.91,142.56,159.37,159.46,163.16,163.70; HRMS m/z
Calcd. for C29H18F20N6ONa ([M þ Na]þ): 869.1120, Found 869.1158.
400 MHz):
d
2.77e2.86 (m, 2H, -CH2-CF2), 3.07 (s, 3H, -CH3), 4.65 (t,
5.3.1.9. 3-((1-Decyl-1H-1,2,3-triazol-4-yl)methyl)-2-ethyl-7-phenyl-
5-(trifluoromethyl) pyrido[2,3-d]pyrimidin-4(3H)-one(5i). IR (KBr,
cmꢁ1): 1684 (lactam CO), 1588 (-C¼N), 1368 (-C-F); UV lmax (nm):
2H, J ¼ 6.86Hz, -CH2-CH2-), 5.34 (s, 2H, -CH2-N-), 7.50e7.52 (m, 3H,
Ar-H), 7.86 (s, 1H, Triazol-H), 8.13 (s, 1H, Py-HC(6)), 8.20e8.23 (m,
2H, Ar-H); 13C NMR (CDCl3, 75 MHz):
d
23.86, 31.65, 40.07, 42.39,
335, 275, 259; 1H NMR (CDCl3, 300 MHz):
d
0.87 (t, 3H, J ¼ 6.04 Hz,
109.65, 116.80, 120.38, 123.90, 124.92, 127.93, 128.98, 131.41, 136.48,
142.34, 159.22, 159.65, 163.53; HRMS m/z Calcd. for C26H17F16N6O
([M þ H]þ): 733.1123, Found 733.1125.
-CH3), 1.22e1.33 (m, 14H, -(CH2)7-), 1.56 (t, 3H, J ¼ 7.55 Hz, -CH3),
1.89 (m, 2H, -CH2-),3.38 (q, 2H, J ¼ 7.55 Hz, -CH2-), 4.30 (t, 2H,
J ¼ 6.79 Hz, -CH2-N-), 5.35 (s, 2H, -CH2-N), 7.49e7.54 (m, 3H, Ar-H),
7.76 (s, 1H, Triazol-H), 8.11 (s, 1H, Py-HC(6)), 8.19e8.24 (m, 2H, Ar-
5.3.1.4. 3-((1-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorodecyl)-
1H-1,2,3-triazol-4-yl)methyl)-2-methyl-7-phenyl-5-(trifluoromethyl)
pyrido[2,3-d]pyrimidine-4(3H)-one(5d). IR (KBr, cmꢁ1): 1692 (lactam
CO), 1598 (-C¼N), 1372 (-C-F); UV lmax (nm): 334, 258; 1H NMR
H); 13C NMR (CDCl3, 75 MHz):
d 11.34, 14.04, 22.59, 26.42, 28.90,
28.94, 29.17, 29.28, 29.38, 30.13, 31.77, 39.43, 50.47, 109.28, 116.89,
124.12, 128.02, 128.95, 131.26, 136.71, 138.48, 138.93, 142.05, 159.40,
159.45, 163.35, 163.60; HRMS m/z Calcd. for C29H35F3N6ONa
([M þ Na]þ): 563.2722, Found 563.2747.
(CDCl3, 400 MHz):
d 2.77e2.88 (m, 2H, -CH2-CF2), 3.07 (s, 3H, -CH3),
4.65 (t, 2H, J ¼ 7.45Hz, -CH2-CH2-), 5.34 (s, 2H, -CH2-N-), 7.49e7.53
(m, 3H, Ar-H), 7.87 (s, 1H, Triazol-H), 8.13 (s, 1H, Py-HC(6)), 8.20e8.23
5.3.1.10. 3-((1-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorod-
ecyl)-1H-1,2,3-triazol-4-yl)methyl)-2-isopropyl-7-phenyl-5-(trifluoro-
methyl) pyrido[2,3-d]pyrimidin-4(3H)-one(5j). IR (KBr, cmꢁ1): 1698
(lactam CO), 1591 (-C¼N), 1371 (-C-F); UV lmax (nm): 335, 275, 258;
(m, 2H, Ar-H); 13C NMR (CDCl3, 75 MHz):
d 23.91, 31.70, 40.10, 42.43,
109.69, 116.86, 120.40, 124.01, 124.95, 127.97, 129.02, 131.44, 136.53,
142.36, 159.22, 159.67, 163.58; HRMS m/z Calcd. for C28H17F20N6O
([M þ H]þ): 833.1144, Found 833.1136.
1H NMR (CDCl3, 300 MHz):
d
1.52 (d, 6H, J ¼ 6.61 Hz, -(CH3)2),
2.73e2.90 (m, 2H, -CH2-CF2), 3.90e3.98 (m, 1H, -CH-), 4.65 (t, 2H,
J ¼ 7.55 Hz, -CH2-CH2-), 5.40 (s, 2H, -CH2-N-), 7.49e7.54 (m, 3H, Ar-
H), 7.87 (s, 1H, Triazol-H), 8.11 (s, 1H, Py-HC(6)), 8.18e8.23 (m, 2H,
5.3.1.5. 3-((1-Decyl-1H-1,2,3-triazol-4-yl)methyl)-2-methyl-7-phenyl-
5-(trifluoromethyl) pyrido[2,3-d]pyrimidin-4(3H)-one(5e). IR (KBr,
cmꢁ1): 1688 (lactam CO), 1587 (-C¼N), 1366 (-C-F); UV lmax (nm):
Ar-H); 13C NMR (CDCl3, 75 MHz):
d 21.02, 31.67, 32.35, 38.99, 42.41,
334, 258; 1H NMR (CDCl3, 400 MHz):
d
0.87 (t, 3H, J ¼ 6.21Hz, -CH3),
109.64, 117.02, 117.10, 120.44, 124.20, 124.85, 128.12, 128.95, 131.23,
136.85, 142.79, 159.53, 159.72, 163.89, 166.75; HRMS m/z Calcd. for
C30H20F20N6ONa ([M þ Na]þ): 883.1276, Found 883.1314.
1.22e1.32 (m, 14H, -(CH2)7-), 1.90 (m, 2H, -CH2-), 3.08 (s, 3H, -CH3),
4.31 (t, 2H, J ¼ 7.10Hz, -CH2-N-), 5.34 (s, 2H, -CH2-N-), 7.50e7.54
(m, 3H, Ar-H), 7.77 (s,1H, Triazol-H), 8.13 (s,1H, Py-HC(6)), 8.21e8.24
(m, 2H, Ar-H); HRMS m/z Calcd. for C28H33F3N6ONa ([M þ Na]þ):
549.2565, Found 549.2561.
5.3.1.11. 2-n-Hexyl-7-phenyl-3-((1-(3,3,4,4,5,5,6,6,7,7,8,8,8-trideca-
fluorooctyl)-1H-1,2,3-triazol-4-yl)methyl)- 5-(trifluoromethyl) pyrido
[2,3-d]pyrimidin-4(3H)-one(5k). IR (KBr, cmꢁ1): 1691 (lactam CO),
1590 (-C¼N), 1371 (-C-F); UV lmax (nm): 335, 276, 258; 1H NMR
5.3.1.6. 2-Methyl-7-phenyl-3-((1-phenyl-1H-1,2,3-triazol-4-yl)
methyl)- 5-(trifluoromethyl) pyrido[2,3-d]pyrimidin-4(3H)-one(5f). IR
(KBr, cmꢁ1): 1683 (lactam CO), 1591 (-C¼N), 1370 (-C-F); UV lmax
(CDCl3, 300 MHz):
-(CH2)2-), 1.53e1.63 (m, 2H, -CH2-), 1.93e2.03 (m, 2H, -CH2-),
d
0.93 (t, 3H, J ¼ 6.79 Hz, -CH3),1.35e1.44 (m, 4H,

C. Kurumurthy et al. / European Journal of Medicinal Chemistry 46 (2011) 3462e3468
3467
2.73e2.90 (m, 2H, -CH2-CF2-), 3.30 (t, 2H, J ¼ 7.93 Hz, -CH2-), 4.65 (t,
2H, J ¼ 7.55 Hz, -CH2-CH2-), 5.35 (s, 2H, -CH2-N-), 7.49e7.58 (m, 3H,
Ar-H), 7.87 (s, 1H, Triazol-H), 8.11 (s, 1H, Py-HC(6)), 8.18e8.23 (m,
colourectal cancer) cell lines were obtained from the National
Centre for Cellular Sciences (NCCS), Pune, India. Cells were cultured
in RPMI-1640 media, supplemented with 10% heat-inactivated fetal
2H, Ar-H); 13C NMR (CDCl3, 75 MHz):
d
13.99, 22.49, 27.44, 29.12,
bovine serum (FBS),1 mM NaHCO3, 2 mM L-glutamine,100 units/ml
31.52, 35.73, 39.54, 42.41, 116.92, 124.91, 128.05, 128.98, 131.34,
136.68, 142.62, 159.40, 159.53, 162.68, 162.89, 163.71; HRMS m/z
Calcd. for C31H27F16N6O ([M þ H]þ): 803.1913, Found 803.1915.
penicillin and 100 mg/ml streptomycin. All cell lines were main-
tained in culture at 37 ꢀC in an atmosphere of 5% CO2.
5.5. Test concentrations
5.3.1.12. 3-((1-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorodec-
yl)-1H-1,2,3-triazol-4-yl)methyl)-2-hexyl-7-phenyl-5-(trifluoromethyl)
pyrido[2,3-d]pyrimidine-4(3H)-one(5l). IR (KBr, cmꢁ1): 1691 (lactam
CO), 1590 (-C¼N), 1370 (-C-F); UV lmax (nm): 336, 276, 259; 1H NMR
Initially, the test compound was dissolved in DMSO (8 mg/ml),
from which 50
obtain experimental stock concentration of 400
aliquots of experimental stock were added to the cultured cells in
ml of stock was diluted to 1 ml in culture medium to
mg/ml. Different
(CDCl3, 300 MHz):
d
0.94 (t, 3H, J ¼ 6.73 Hz, -CH3), 1.36e1.44 (m, 4H,
-(CH2)2-), 1.55e1.61 (m, 2H, -CH2-), 1.95e2.02 (m, 2H, -CH2-),
2.76e2.87 (m, 2H, -CH2-CF2-), 3.30 (t, 2H, J ¼ 7.69 Hz, -CH2-), 4.65 (t,
2H, J ¼ 7.55 Hz, -CH2-CH2-), 5.35 (s, 2H, -CH2-N-), 7.50e7.53 (m, 3H,
Ar-H), 7.86 (s,1H, Triazol-H), 8.12 (s,1H, Py-HC(6)), 8.20e8.23 (m, 2H,
the medium (final volume of 200
ml) to attain the required
concentrations.
5.6. Cytotoxicity
Ar-H); 13C NMR (CDCl3, 75 MHz):
d 13.95, 22.47, 27.40, 29.10, 31.47,
35.63, 39.61, 42.47, 116.79, 124.63, 128.12, 129.08, 131.43, 136.78,
142.73, 159.38, 159.62, 162.71, 162.94, 163.83; HRMS m/z Calcd. for
C33H26F20N6ONa ([M þ Na]þ): 925.1746, Found 925.1779.
In all experiments, different cell lines were seeded at a final
density of 2 ꢃ 104 cells/well, in 96 well microtiter plates. Cytotox-
icty was measured using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,
5-diphenyl tetrazolium bromide] assay, according to the method of
Mosmann (1983) [27]. Briefly, the cells (2 ꢃ 104) were seeded in
each well containing 0.1 ml of medium in 96 well plates. After
overnight incubation, the cells were treated with different test
5.3.1.13. 4-((1-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorodec-
yl)-1H-1,2,3-triazol-4yl)methoxy)-2-methyl-7-phenyl-5-(trifluorome-
thyl) pyrido[2,3-d]pyrimidine(6a). IR (KBr, cmꢁ1): 1658 (-C¼N), 1372
(-C-F), 1205 (C-O-C); UV lmax (nm): 341, 251; 1H NMR (CDCl3,
concentrations of test compounds (5e200
mg/ml) at identical
400 MHz):
d 2.78e2.89 (m, 2H, -CH2-CF2), 3.10 (s, 3H, -CH3), 4.63 (t,
conditions with five replicates each. The cell viability was assessed
2H, J ¼ 7.56Hz, -CH2-N-), 5.89 (s, 2H, -CH2-O-), 7.53e7.57(m, 3H, Ar-
H), 7.68 (s,1H, Triazol-H), 7.98 (s,1H, Py-HC(6)), 8.14e8.19 (m, 2H, Ar-
H); HRMS m/z Calcd. for C28H16F20N6ONa ([M þ Na]þ): 855.0963,
Found 855.0985.
after 24 h, by adding 10 ml of MTT (5 mg/ml) per well. The plates
were incubated at 37 ꢀC for additional 3 h. The medium was dis-
carded and the formazan blue, which formed in the cells, was
dissolved with 100 ml of DMSO. The rate of colour production was
measured at 570 nm in a spectrophotometer (Spectra MAX Plus;
Molecular Devices; supported by SOFTmax PRO-5.4). The percent
inhibition of cell viability was determined with reference to the
control values (without test compound). The data were subjected to
linear regression analysis and the regression lines were plotted for
the best straight-line fit. The IC50 (inhibition of cell viability)
concentrations were calculated using the respective regression
equation.
5.3.1.14. 2-Ethyl-7-phenyl-4-((1-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-
octyl)-1H-1,2,3-triazol-4-yl)methoxy)- 5-(trifluoromethyl) pyrido[2,3-d]
pyrimidine(6b). IR (KBr, cmꢁ1): 1672 (-C¼N), 1373 (-C-F), 1206 (C-O-
C); UV lmax (nm): 342, 252; 1H NMR (CDCl3, 300 MHz):
d 1.40 (t, 3H,
J ¼ 7.17 Hz, -CH3), 2.68e2.85 (m, 2H, -CH2-CF2), 3.15 (q, 2H,
J ¼ 7.17 Hz, -CH2-), 4.62 (t, 2H, J ¼ 7.36Hz, -CH2-N-), 5.87 (s, 2H, -CH2-
O-), 7.52e7.56 (m, 3H, Ar-H), 7.67 (s, 1H, Triazol-H), 7.97 (s, 1H, Py-
HC(6)), 8.13e8.18 (m, 2H, Ar-H); HRMS m/z Calcd. for C27H19F16N6O
([M þ H]þ): 747.1312, Found 747.1315.
Acknowledgements
5.3.1.15. 4-((1-(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorode-
cyl)-1H-1,2,3-triazol-4yl)methoxy)-2,7-diphenyl-5-(trifluoromethyl)
pyrido[2,3-d]pyrimidine(6c). IR (KBr, cmꢁ1): 1670 (-C¼N),1369 (-C-F),
1203 (C-O-C); UV lmax (nm): 340, 275; 1H NMR (CDCl3, 300 MHz):
Authors are thankful to Director, IICT for his constant encour-
agement and authors (C. Kurumurthy, P. Sambasiva Rao, B. Veer-
aswamy and G. Santhosh kumar) are thankful to Council of
Scientific and Industrial Research(CSIR), India for providing finan-
cial assistance in the form of Junior Research Fellowship.
d
2.76e2.95 (m, 2H, -CH2-CF2-), 4.71 (t, 2H, J ¼ 7.29 Hz, -CH2-N-), 6.00
(s, 2H, -CH2-O-), 7.51e7.58 (m, 6H, Ar-H), 7.78 (s, 1H, Triazol-H),
8.24e8.32 (m, 3H, Ar-H), 8.68e8.72 (m, 2H, Ar-H); HRMS m/z
Calcd. for C33H19F20N6O ([M þ H]þ): 895.1300, Found 895.1326.
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