Synthesis of new derivatives of pyrazol-chromeno[2,3-d]pyrimidine-ones by a one-pot three-component reaction

Article abstract of DOI:10.1007/s13738-015-0701-1

A new three-component reaction between salicylaldehydes, barbituric acid, pyrazolones, in the presence of para-toluenesulfonic acid, efficiently provides pyrazol-chromeno[2,3-d]pyrimidine-ones derivatives in good yields in ethanol/water at 70 °C. This mul

Full text of DOI:10.1007/s13738-015-0701-1

J IRAN CHEM SOC
DOI 10.1007/s13738-015-0701-1
ORIGINAL PAPER
Synthesis of new derivatives of pyrazol‑chromeno[2,3‑d]
pyrimidine‑ones by a one‑pot three‑component reaction
Ebrahim Soleimani1,2 · Manizheh Ghanbarian · Parisa Saei · Mojtaba Taran
1
1
3
Received: 28 February 2015 / Accepted: 12 July 2015
©
Iranian Chemical Society 2015
Abstract A new three-component reaction between salic-
ylaldehydes, barbituric acid, pyrazolones, in the presence
of para-toluenesulfonic acid, efficiently provides pyrazol-
chromeno[2,3-d]pyrimidine-ones derivatives in good yields
in ethanol/water at 70 °C. This multicomponent reaction
showed high atom economy.
performed in aqueous media, have become increasingly
useful tools for the synthesis of chemically and biologically
important compounds because of their environmentally
friendly atom economy and green characteristics [1–7].
Among the wide variety of heterocycles that have been
explored for developing potential pharmacologically active
compounds, pyrazoles fused with different heterocycles that
are known to contribute to various chemotherapeutic effects
have emerged as antimicrobial [8, 9], antifungal [10], and
antiviral agents [11]. In addition, some fused pyrazole deriv-
atives were reported to induce various antileukemic [12],
antitumor [13, 14], and antiproliferative [15, 16] activities.
The benzopyrano[2,3-d]pyrimidines are organic com-
pounds which are constructed from two fused benzopyran
and pyrimidine rings which exhibit extremely diverse bio-
logical and pharmaceutical activities [17–28]. The benzo-
pyrans (4H-chromene) have shown a wide range of biologi-
cal activities such as anti-HBV, cytotoxic [17], antibacterial
Graphical Abstract
R3
N
N
2
R
O
HO
O
R2
O
CHO
OH
N
R1
NH
R3
N
PTSA
EtOH:H O, 70 C
2
R1
NH
+
+
o
O
N
H
O
O
N
H
O
Keywords Chromeno[2,3-d]pyrimidine ·
Multicomponent reactions · Salicylaldehyde · Barbituric
acid · PTSA
[
18], antioxidant [19], antigenotoxic [20], ATP sensitive
Introduction
potassium channel openers [21], and antiangiogenic activ-
ity [22]. On the other hand, pyrimidine scaffold is the base
of many bioactive molecules such as antitubercular [23],
antibacterial [24], antitumor [25], antiinflammatory [26],
antifungal [27], and antileishmanial agent [28]. Conse-
quently, synthetic methodologies for the synthesis of novel
benzopyrano[2,3-d]pyrimidine [28] are of particular inter-
ests to organic and medicinal chemists.
Multicomponent reactions (MCRs), because of their pro-
ductivity, simple procedures, time-saving manner, conver-
gence, and facile execution, are one of the best tools in
combinatorial chemistry [1–7]. MCRs, particularly those
*
Ebrahim Soleimani
Recently, we described the synthesis of alkyl-
H-chromeno[2,3-d]pyrimidine-5-carboxamides via a new
e_soleimanirazi@yahoo.com
1
1
2
3
three-component reaction of isocyanide, barbituric acid,
and a salicylaldehyde in the presence of acetic acid in etha-
nol/water mixture at 75 °C [29]. Herein, we aim to expand
the versatility of the reaction using pyrazolones instead of
isocyanides. Therefore, we examined the reaction between
the salicylaldehydes 1, barbituric acid 2, and pyrazolones 3
Department of Chemistry, Razi University,
6
7149-67346 Kermanshah, Iran
Department of Chemistry, College of Sciences, Kermanshah
Branch, Islamic Azad University, Kermanshah, Iran
Department of Biology, Razi University,
6
7149-67346 Kermanshah, Iran
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J IRAN CHEM SOC
R3
N
N
2
R
HO
O
O
R2
O
CHO
OH
N
N
PTSA
NH
R1
NH
R3
R1
+
+
o
EtOH:H O, 70 C
2
O
N
H
O
O
N
H
O
4
5
3
6
EtOH
r.t., 5 min
O
O
+
R2 NH NH2
R3
OEt
1
2
Scheme 1 Synthesis of pyrazol-chromeno[2,3-d]pyrimidine-ones
Table 1 Optimization of the reaction
Ph
N
N
Me
O
HO
O
CHO
Ph
O
N
NH
N
PTSA
NH
+
+
Me
OH
O
N
H
O
O
N
H
O
Entry
Solvent
Temperature
Yield (%)
1
2
3
4
5
6
7
8
9
Water
70
70
70
70
70
70
25
70
70
70
25
50
100
80
Ethanol
30
Methanol
Ethyl acetate
Acetonitrile
Toluene
70
85
80
Trace
Trace
95
Dichloromethane
Water/ethanol (4:1)
Water/ethanol (2:1)
Water/Ethanol (1:1)
Water/ethanol (4:1)
Water/ethanol (4:1)
Water/ethanol (4:1)
80
10
11
12
13
70
40
75
95
a
The reaction was carried out by salicylaldehyde (1.0 mmol), barbituric acid (1.0 mmol) and 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one
(
1.0 mmol) catalyzed by PTSA in different solvents and temperature
b
Isolatedyiled
in the presence of PTSA in mixture of water/ethanol (4:1)
at 70 °C (Scheme 1). It should be noted that pyrazolone 3
was synthesized by the condensation between β-keto esters
For optimization reaction, we achieved effect of sol-
vents and temperature on the yield of the reaction. There-
fore, the reaction of salicylaldehyde and barbituric acid with
3-methyl-1-phenyl-1H-pyrazol-5(4H)-one in the presence
1
and hydrazines 2 in ethanol after 5 min and purified
before used in above reaction [30].
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J IRAN CHEM SOC
Table 2 Synthesis of pyrazol-chromeno[2,3-d]pyrimidine-ones derivatives
HN
N
HN
N
N
N
N
N
HO
O
HO
Me
O
Me
O
O
HO
HO
NH
Me
NH
NH
NH
O
N
H
O
O
N
H
O
O
N
H
O
O
N
H
O
OMe
6
a
6b
6c
6d
HN
N
N N
N
N
Me
Me
O
HO
HO
O
O
HO
Me
Br
NH
NH
NH
O
N
H
O
O
N
H
O
O
N
H
O
OMe
6
f
6g
6
e
Entry
R1
R2
R3
Product
Yield (%)
1
2
3
4
5
6
7
H
Pr
H
6a
6b
6c
6d
6e
6f
83
60
89
95
91
87
60
H
Pr
MeO
Me
H
Ph
Ph
Ph
H
Me
Me
Me
Pr
Br
Me
MeO
Ph
Me
6g
a
The reaction was carried out by salicylaldehydes (1.0 mmol), barbituric acid (1.0 mmol), and pyrazolones (1.0 mmol) catalyzed by PTSA in
water/ethanol (4:1) at 70 °C
b
Isolatedyiled
H
N
N
OH
O
HN N
3
HO
O
O
CHO
OH
NH
NH
NH
+
O
N
O
O
N
H
O
O
N
H
O
1
2
7
6
Scheme2 Proposed mechanism
and PTSA was selected as a model reaction. We first investi-
gated the model reaction rate in different solvents by meas-
uring the isolated yield using identical amounts of reactants
in the presence of 10 % mol of PTSA for a fixed reaction
time of 12 h at 70 °C (Table 1, entries 1–8). The desired
product was obtained in polar solvents, such as water, etha-
nol and methanol, ethyl acetate, and acetonitrile but water
can afford the product in good yield even better than other
solvents (Table 1, entry 8). It was found that addition of
ethanol to the water solution can improve the reaction
1
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J IRAN CHEM SOC
outcome and interestingly (Table 1, entries 8–10) when the
reaction was performed in water/ethanol mixture (4:1) the
corresponding product was obtained qualitatively (Table 1,
entry 8). The desired product was not obtained in non-polar
solvents, such as dichloromethane, toluene (Table 1, entries
(1 mmol) were added and stirred for 10 h at 70 °C (pyra-
zolone derivatives made of hydrazine hydrate and alkyl
acetoacetate in ethanol at room temperature in 5 min).
After completion of the reaction, as indicated by TLC, the
precipitate was washed with ethanol and the products were
obtained as a white powder.
6–7). This effect can be explained by a simple acid catalysis
mechanism facilitated by the strong hydrogen bond interac-
tion at the organic-water interface, which stabilizes the reac-
tion intermediate. Next, we studied the model reaction in
water/ethanol mixture (4:1) at different temperatures (entry
5‑(5‑Hydroxy‑3‑propyl‑4, 5‑dihydro‑1H‑pyra‑
zol‑4‑yl)‑1H‑chromeno[2, 3‑d]pyrimidine‑2, 4(3H,
5H)‑dione (6a)
8
and entries 11–13). The reaction rate increased as the tem-
perature was raised. At 70 °C, the maximum yield (93 %)
was obtained in a reaction time of 12 h (entry 8).
White powder (0.28 g, yield 83 %); mp 226–228 °C. IR
−1
(KBr) (νmax/cm ): 3398 (NH), 1725 (C=O), 1647, 1597.
+
3
1
With the optimized condition established above, we next
attempted to extend the process to four different salicylalde-
hydes (3-methoxy, 5-methyl and 5-bromosalicylaldehyde and
salicylaldehyde) and various types of pyrazolones. The results
have been summarized in Table 2. The structures of the prod-
ucts were established by different spectroscopic methods (for
details see Experimental section). In all cases, good yields
were obtained, whatever the nature of the subsistent present
on the salicylaldehyde (electron donating or electron with-
MS, m/z: 340 (M ). H NMR (400 MHz, DMSO-d ): δ
6
H
(ppm) 0.9 (3H, t, J = 7.2 Hz, CH ), 1.52 (2H, m, CH )
HH
3
2
3
2.50 (2H, t, J = 7.2 Hz, CH ), 3.40 (OH exchanged with
HH
2
water of DMSO-d ), 4.77 (1H, s, CH), 7.05–7.24 (4H, m,
6
1
3
H-Ar), 10.92 (3H, s, 3NH). C NMR (100 MHz, DMSO-
d ): δ (ppm) 13.7 (CH ), 22.0 (CH ), 25.6 (CH ), 26.3
6
C
3
2
2
(CH), 87.3 (C=C–OH), 115.7 (C=C–O), 124.6, 125.1,
125.3, 127.6, 129.6, 129.7, 142.0, 148.5, 153.6, 158.91,
163.2. Anal. Calcd for C H N O : C, 59.99; H, 4.74; N,
1
7
16
4
4
1
drawing). The structure of the products was deduced from H
16.46. Found: C, 59.96; H, 4.73; N, 16.44.
13
NMR and C NMR spectra (see the experimental section).
To explore the scope and limitations of this process,
we further examined the reactions of various withdrawing
groups of salicylaldehydes such as 5-nitrosalicylaldehyde,
5‑(5‑Hydroxy‑3‑propyl‑1H‑pyrazol‑4‑yl)‑9‑meth‑
oxy‑1H‑chromeno[2,3‑d]pyrimidine‑2, 4(3H, 5H)‑dione
(6b)
3-nitrosalicylaldehyde, 5-fluorosalicylaldehyde, and 3,5-dif-
luorosalicylaldehyde under reaction condition. However, in
all these cases, the desired products 6 were not formed.
Mechanistically, it is conceivable that the reaction
involves the initial formation of the activated alkene (ben-
zopyran ring) 7 through a Knoevenagel condensation of
salicylaldehydes 1 and barbituric acid 2. Benzopyran ring 7
undergoes nucleophilic addition with the pyrazolone 3 fol-
lowed tautomerization to afford 4 (Scheme 2).
White powder (0.22 g, yield 60 %); mp 279 °C. IR (KBr)
−1
(νmax/cm ): 3397 (NH), 1720 (C=O), 1643, 1596. MS,
m/z: 370 (M ). H NMR (400 MHz, DMSO-d ): δ (ppm)
+
3
1
6
H
0.86 (3H, t, J = 7.2 Hz, CH ), 1.50 (2H, m, CH ),
HH
3
2
3
2.50 (2H, t, J = 7.2 Hz, CH ), 3.40 (OH exchanged
HH
2
with water of DMSO-d ), 3.83 (3H, s, OCH ), 4.74 (1H,
6
3
s, CH), 6.67–7.06 (3H, m, H-Ar), 10.88, 11.69, 11.78 (3H,
1
3
3s, 3NH). C NMR (100 MHz, DMSO-d ): δ (ppm) 13.9
6
C
In conclusion, we have developed a new pyrazolone-
based MCRs for the synthesis of a wide range of pyrazol-
chromeno[2,3-d]pyrimidine-ones from salicylaldehydes
and barbituric acid with pyrazolones. This high yielding
reaction has been shown to display a good functional group
tolerance, while the product isolation is very straightfor-
ward. We hope that this approach may be valuable to others
seeking for novel synthetic fragments with unique proper-
ties for medicinal chemistry programs.
(CH ), 22.2 (CH ), 25.7 (CH ), 26.3 (CH), 55.7 (OCH ),
3 2 2 3
87.2 (C=C–OH), 110.2 (C=C–O), 120.7, 123.2, 124.8,
125.4, 129.3, 138.1, 146.9, 149.5, 153.8, 161.2, 163.3.
Anal. Calcd for C H N O : C, 58.37; H, 4.90; N, 15.13.
1
8
18
4
5
Found: C, 58.38; H, 4.91; N, 15.16.
5‑(5‑Hydroxy‑3‑methyl‑1‑phenyl‑1H‑pyra‑
zol‑4‑yl)‑7‑methyl‑1H‑chromeno[2,3‑d]pyrimidine‑2,
4(3H, 5H)‑dione (6c)
White powder (0.35 g, yield 89 %); mp 245 °C. IR (KBr)
−
1
General procedure for synthesis
of pyrazol‑chromeno[2,3‑d]pyrimidine‑ones (6a–g)
(νmax/cm ): 3397 (NH), 1727 (C=O), 1641, 1594. MS,
+
1
m/z: 402 (M ). H NMR (400 MHz, DMSO-d ): δ (ppm)
6
H
1
.74 (3H, s, CH ), 2.22 (3H, s, CH ), 4.69 (1H, s, CH),
3 3
A solution of salicylaldehyde (1 mmol) and barbituric
acid (1 mmol) in ethanol/water (1:4) (5 mL) was stirred
at 70 °C. After 2 h, PTSA (0.1 mmol) and pyrazolones
6.93–7.63 (8H, m, H-Ar), 10.70, 10.90, 11.76 (3H, 3s, OH,
1
3
2NH). C NMR (100 MHz, DMSO-d ): δ (ppm) 20.2
6
C
(CH ), 26.1 (CH ), 29.5 (CH), 80.2 (C=C–OH), 114.8
3
3
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J IRAN CHEM SOC
(
1
C=C–O), 115.5, 117.9, 123.0, 124.3, 128.8, 129.5, 135.4,
38.9, 146.9, 149.6, 152.7, 154.4, 154.4, 163.3, 165.1.
Anal. Calcd for C H N O : C, 65.66; H, 4.51; N, 13.92.
5‑(5‑Hydroxy‑3‑methyl‑1‑phenyl‑1H‑pyra‑
zol‑4‑yl)‑9‑methoxy‑1H‑chromeno[2,3‑d]pyrimi‑
dine‑2,4(3H,5H)‑dione (6g)
2
2
18
4
4
Found: C, 65.65; H, 4.53; N, 13.94.
White powder (0.25 g, yield 60 %); mp 269 °C. IR (KBr)
−1
5
‑(5‑Hydroxy‑3‑methoxy‑1‑phenyl‑1H‑pyra‑
(νmax/cm ): 3398 (NH), 1722 (C=O), 1630, 1591. MS,
m/z: 418 (M ). H NMR (400 MHz, DMSO-d ): δ (ppm)
+
1
zol‑4‑yl)‑1H‑chromeno[2,3‑d]pyrimidine‑2, 4(3H, 5H)‑
6
H
dione (6d)
2.32 (3H, s, CH ), 3.34 (OH exchanged with water of
3
DMSO-d ), 3.83 (3H, s, OCH ), 4.73 (1H, s, CH), 6.76–
6
3
1
3
White powder (0.37 g, yield 95 %); mp 285–288 °C. IR
7.63 (8H, m, H-Ar), 10.79, 10.95 (2H, 2s, 2NH). C NMR
−
1
(
KBr) (νmax/cm ): 3389 (NH), 1788 (C=O), 1486, 1644.
(100 MHz, DMSO-d ): δ (ppm) 14.3 (CH ), 26.2 (CH),
6
C
3
+
1
MS, m/z: 388 (M ). H NMR (400 MHz, DMSO-d ): δ
ppm) 2.34 (3H, s, CH ), 3.35 (OH exchanged with water
of DMSO-d ), 4.72 (1H, s, CH), 7.04–7.67 (9H, m, H-Ar),
0.80, 10.93 (2H, 2s, 2NH). C NMR (100 MHz, DMSO-
55.7 (OCH ), 87.0 (C=C–OH), 106.0 (C=C–O), 106.5,
6
H
3
(
110.6, 110.7, 119.0, 120.7, 124.1, 124.4, 124.5, 128.8,
146.9, 149.5, 151.7, 154.3, 163.6, 165.9. Anal. Calcd for
C H N O : C, 63.15; H, 4.34; N, 13.39. Found: C, 63.14;
3
6
1
3
1
2
2
18
4
5
d6): δC (ppm) 12.8 (CH ), 26.3 (CH), 87.3 (C=C–OH),
H, 4.34; N, 13.37.
3
1
1
1
1
09.5 (C=C–O), 115.6, 117.8, 120.6, 123.3, 124.0, 128.1,
25.1, 127.8, 128.7, 129.5, 137.1, 146.9, 149.6, 154.4,
63.2. Anal. Calcd for C H N O : C, 64.94; H, 4.15; N,
Acknowledgments We gratefully acknowledge financial support
from the Iran National Science Foundation (INSF) and Research
Council of Razi University.
2
1
16
4
4
4.43. Found: C, 64.95; H, 4.16; N, 14.44.
7
‑Bromo‑5‑(5‑hydroxy‑3‑methyl‑1‑phenyl‑1H‑pyra‑
References
zol‑4‑yl)‑1H‑chromeno[2,3‑d]pyrimidine‑2, 4(3H, 5H)‑
dione (6e)
1.
2.
3.
Multicomponent Reactions ed. by J. Zhu, H. Bienaymé (Wiley,
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White powder (0.35 g, yield 91 %); mp 282 °C. IR (KBr)
−
1
(
4
ν
/cm ): 3389 (NH), 1716 (C=O), 1662, 1075. MS, m/z:
max
+
67 (M ). H NMR (400 MHz, DMSO-d ): δ (ppm) 2.38
6 H
1
(
1
3H, s, CH ), 4.76 (1H, s, CH), 6.99–7.72 (H-Ar), 10.84,
0.98 (2H, 2s, NH), 11.67 (1H, s, OH). C NMR (100 MHz,
4. E. Soleimani, M.M. Khodaei, N. Batooie, M. Baghbanzadeh,
3
13
Green Chem. 13, 566–569 (2011)
5
6
.
.
E. Soleimani, M. Zainali, J. Org. Chem. 76, 10306–10311 (2011)
E. Soleimani, M. Zainali, S. Samadi, Tetrahedron Lett. 52, 4186–
DMSO-d ): δ (ppm) 10.8 (CH ), 26.2 (CH), 84.8 (C=C–
6
C
3
OH), 107.5 (C=C–O), 115.0, 117.9 108.7, 124.2, 126.3,
4
188 (2011)
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9, 9832–9838 (2013)
1
1
1
28.8, 130.7, 131.8, 140.1, 143.4, 149.5, 154.1, 158.8, 163.4,
6
68.4. Anal. Calcd for C H BrN O : C, 53.98; H, 3.24; N,
21
15
4
4
8
.
B.S. Holla, M. Mahalinga, M.S. Karthikeyan, P.M. Akberali,
1.99. Found: C, 53.94; H, 3.24; N, 11.96.
N.S. Shetty, Bioorg. Med. Chem. 14, 2040–2047 (2006)
9
.
A.H. Shamroukh, M.E.A. Zaki, E.M.H. Morsy, F.M. Abdel-
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5
‑(5‑hydroxy‑3‑propyl‑1H‑pyrazol‑4‑yl)‑7‑me‑
3
40–345 (2007)
thyl‑1H‑chromeno[2,3‑d]pyrimidine‑2, 4(3H, 5H)‑dione
6f)
1
1
0. E. Akbas, I. Berber, Eur. J. Med. Chem. 40, 401–405 (2005)
1. R.Z. Yan, X.Y. Liu, W.F. Xu, C. Pannecouque, M. Witvrouw, E.
DeClercq, Arch. Pharm. Res. 29, 957–962 (2006)
(
White powder (0.31 g, yield 87 %); mp 246 °C. IR (KBr)
12. L.C. Chou, L.J. Huang, J.S. Yang, F.Y. Lee, C.M. Teng, S.C.
−1
Kuo, Bioorg. Med. Chem. 15, 1732–1740 (2007)
13. J. Li, Y.F. Zhao, X.L. Zhao, X.Y. Yuan, P. Gong, Arch. Pharm.
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(
ν
/cm ): 3399 (NH), 1721 (C=O), 1643, 1591. MS,
max
+
1
m/z: 354 (M ). H NMR (400 MHz, DMSO-d ): δ (ppm)
0
(
exchanged with water of DMSO-d ), 4.72 (1H, s, CH),
6
6
H
3
.98 (3H, t, J = 7.2 Hz, CH ), 1.49 (2H, m, CH ), 2.20
HH
3
2
14. V. Krystof, D. Moravcova, M. Paprskarova, P. Barbier, V. Peyrot,
3
3H, s, CH ), 2.50 (2H, t, J = 7.2 Hz, CH ), 3.34 (OH
A. Hlobilkova, L. Havlicek, M. Strnad, Eur. J. Med. Chem. 41,
3
HH
2
1
405–1411 (2006)
6
1
3
15. S. Schenone, O. Bruno, A. Ranise, F. Bondavalli, C. Brullo, P.
Fossa, L. Mosti, G. Menozzi, F. Carraro, A. Naldini, C. Bernini,
F. Manettic, M. Botta, Bioorg. Med. Chem. Lett. 14, 2511–2517
(2004)
.91–7.03 (3H, m, H-Ar), 10.00 (3H, s, 3NH). C NMR
(
100 MHz, DMSO-d ): δ (ppm) 13.9 (CH ), 20.3 (CH ),
6
C
3
3
2
2.0 (CH ), 25.7 (CH), 26.4 (CH ), 87.3 (C=C–OH), 104.9
2
2
1
6. G. Daidone, D. Raffa, B. Maggio, M.V. Raimondi, F. Plescia, D.
Schillaci, Eur. J. Med. Chem. 39, 219–224 (2004)
(
C=C–O), 115.5, 124.3, 128.1, 129.7, 129.8, 134.0, 146.6,
1
49.6, 153.9, 163.3, 164.0. Anal. Calcd for C H N O :
1
8
18
4
4
1
7. S.C. Ren, F.Y. Sheau, M.L. Chih, G. Amooru, T.K. Damu, C.P.
Cheng, F.B. Kenneth, L.K. Hsiung, W.T. Shung, Bioorg. Med.
Chem. 17, 6137–6143 (2009)
C, 61.01; H, 5.12; N, 15.81. Found: C, 61.07; H, 5.10; N,
5.82.
1
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J IRAN CHEM SOC
1
1
2
2
2
2
2
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