Chlorotrimethylsilane mediated synthesis of 5-(2hydroxybenzoyl)pyrimidines from 3-formylchromones

Article abstract of DOI:10.3987/COM-07-11240

The recyclization of 3-formylchromones with a variety of 1,3-NCNbinucleophiles promoted by chlorotrimethylsilane was investigated. A simple and flexible general procedure for the synthesis of series of 5-(2hydroxybenzoyl)pyrimidines and their heterofused analogues was proposed. A set of pyrimidines was obtained in high preparative yields.

Full text of DOI:10.3987/COM-07-11240

HETEROCYCLES, Vol. 75, No. 3, 2008
583
HETEROCYCLES, Vol. 75, No. 3, 2008, pp. 583 - 597. © The Japan Institute of Heterocyclic Chemistry
Received, 10th October, 2007, Accepted, 3rd December, 2007, Published online, 7th December, 2007. COM-07-11240
CHLOROTRIMETHYLSILANE MEDIATED SYNTHESIS OF 5-(2-
HYDROXYBENZOYL)PYRIMIDINES FROM 3-FORMYLCHROMONES
Sergey V. Ryabukhin,a,b* Andrey S. Plaskon,a,b Dmitriy M. Volochnyuk,a,c
Sergey E. Pipko,a and Andrey A. Tolmachevb
aEnamine Ltd. 23 A. Matrosova st., 01103 Kyiv, Ukraine
bNational Taras Shevchenko University, 62 Volodymyrska st., 01033 Kyiv,
Ukraine
cInstitute of Organic Chemistry, National Academy of Sciences of Ukraine,
Murmanska 5, 02094 Kyiv, Ukraine
Fax: +380 44 5373253
E-mail: Ryabukhin@mail.enamine.net
Abstract – The recyclization of 3-formylchromones with a variety of 1,3-NCN-
binucleophiles promoted by chlorotrimethylsilane was investigated. A simple and
flexible general procedure for the synthesis of series of 5-(2-
hydroxybenzoyl)pyrimidines and their heterofused analogues was proposed. A set
of pyrimidines was obtained in high preparative yields.
INTRODUCTION
Pyrimidines are useful class of organic compounds.1,2 The pyrimidine scaffold plays an important role as
component of antiviral,3 antibacterial,4a antimicrobial,4b anti-inflammatory,4c antifungal,4d
a
antiparasitic,4e antimalarial,4f,4g antiprotozoal,5a antihypotensive,5b antiproliferative,5c anxiolytic,5d
anorectic,5e fungistatic5f agents etc. Therefore, the search for effective methods for synthesis of
pyrimidine libraries for high-throughput screening remains an actual problem. Although various methods
have been developed for pyrimidine synthesis1,2 novel methods are still desired.6 One of methods to
obtain the pyrimidine core is based on the reaction of 1,3-NCN-binucleophiles (amidines, guanidines etc)
with various 1,3-dicarbonyl compounds as 1,3-CCC-bielectrophiles.7 3-Formylchromones I were used as
1,3-CCC-bielectrophiles as well.8-10 Amidines,9a-d guanidine,9d-h nitroguanidine,9f thiourea,9f 2-
methylisothiourea sulfate,9h N-unsubstituted aminopyrazoles,10a-c 2-amino-4-aryl-6-phenyl-1,4-dihydro-
pyrimidine-5-carboxylic acid ethyl ester10d and N-triphenylphosphoranylidene benzamidine were used as
1,3-NCN-binucleophiles II in the reactions with 3-formylchromones I.10e The main problem is the fact

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HETEROCYCLES, Vol. 75, No. 3, 2008
that 3-formylchromone I possess three electrophilic centers: C-4, formyl group at C-3 and unsaturated C-
2 carbon atom, what leads to the formation of mixtures of 5-(2-hydroxybenzoyl)pyrimidines III and 5-
hydroxybenzopyrano[4,3-d]pyrimidines IV (Scheme 1) in most of cases.
R
O
O
O
OH
R = H, Me, NH2, NHNO2, SH, SMe
N
O
N
R
Ar
O
+
HN
N
+
R
CO2Et
Ph
R
N
NH2
=
NH2
N
N
R
NH2
II
HN
III
N
H
H2N
I
N
OH
H
IV
Scheme 1
During the course of our 3-formylchromone recyclization studies involving [3+3] cyclocondensation of 3-
formylchromones with acetic acid amides11a which have an electron-withdrawing group at α-position,
various π-electron-rich amino heterocycles and donor anilines,11b and various benzimidazoles, bearing
CH2-group at the 2-nd position,11c we explored the formation of 5-(2-hydroxybenzoyl) substituted
pyrimidines via coupling of 3-formylchromone 1 with various amidines and their heterocyclic analogues.
RESULTS AND DISCUSSION
We have demonstrated in our earlier studies that chlorotrimethylsilane (TMSCl) is a convenient
condensating agent for the recyclization of 3-formylchromones afford regioselective formation of 2-
hydroxybenzoyl derivatives of nitrogen heterocycles,11 as well as for other condensations of carbonyl
compounds.12 Therefore we decided to use TMSCl as a promoter and water scavenger in the reactions
with various amidines and their heterocyclic analogues.
3-Formylchromones 1 react with equimolar amount of benzamidine 2a or pyrrolidine-1-carboxamidine
sulfate 2b in DMF solution at 100 °С in the presence of 3 equivalents of chlorotrimethylsilane (TMSCl)
giving 5-(2-hydroxybenzoyl)pyrimidines 3a and 3b as single products of recyclization in preparative
yields (Scheme 2, Table 1). Aminotriazoles 4a-e react with 3-formylchromones as 1,3-NCN-
binucleophiles forming [1,2,4]triazolo[1,5-a]pyrimidines 5.13 1H-Benzimidazole-2-amine 6 and 2-amino-
1H-imidazole-4,5-dicarbonitrile 8 react similar affording pyrimido[1,2-a]benzimidazole 7b and
imidazo[1,2-a]pyrimidine 9a, respectively. 1H-Pyrazole-5-amines 10a-e containing nitrile or carbethoxy
group at 4-position which prevents the reaction with 3-formylchromone 1 on carbon atom, forming
pyrazolo[1,5-a]pyrimidines 11. Reactions of 1H-indazole-3-amine 12a with 1,3-CCC-bielectrophiles are
poorly studied; but under the conditions found both mentioned compound and its heterocyclic analogues
react with 3-formylchromone 1 forming compounds 13. The duration of the reflux (6 to 12 hours) was
found to be important for the purity of the final products.

HETEROCYCLES, Vol. 75, No. 3, 2008
585
X
4, 6, 8, 10, 12
O
O
O
OH
R1
X
N
R2
N
R1
2a,b
NH2
HN
NH2
N
O
N
H
R1
TMSCl, DMF
TMSCl, DMF
N
R2
O
1a-f
3aa, 3bb
a: R1 = H
b: R1 = Me
c: R1 = OMe
d: R1 = F
e: R1 = Cl
f: R1 = Br
HO
a: R2 = Ph
b: R2 = N(CH2)4
5, 7, 9, 11, 13
N
N
N
NH2
NH2
R
N
N
H
H
X
4a-e
6
NH2
N
NH2
=
NC
R
EWG
N
Ring
H
N
R, EWG and Ring of entries 4a-e, 10a-e and 12a-c see Table 1
N
NH2
NH2
NC
N
H
N
N
H
H
12a-c
8
10a-e
Scheme 2
NMR spectra indicate the exclusive formation of 2-hydroxybenzoyl derivatives of pyrimidine; the
formation of 5-hydroxybenzopyrano[4,3-d]pyrimidines IV was not detected. This conclusion is based on
the observation of typical pyrimidine-ring shift values of δ ~ 8.0-9.0 ppm and ~9.1-9.6 ppm with coupling
constant 4JHH ~ 0.8-2.3 Hz; on the presence of signal of carbonyl carbon atom in 13C NMR spectra at δ ~
191.6-194.0 ppm; and on the appearance of signal of carbon atom bounded to hydroxyl group at δ ~
157.2-158.4 ppm in 13C NMR spectra. The indirect confirmations are the presence of wide absorption
band at 3600-3300 cm-1 in IR spectrum corresponding to valence vibrations of hydroxyl group, and
intensive peak at ~ 1630 cm-1 corresponding to valence vibrations of carbonyl group.
In the case of N-1H-benzimidazol-2-ylguanidines 2c,d and N-1,3-benzoxazol-2-ylguanidine 2e,
[5+1]cyclization takes place leading to the formation of 2-amino[1,3,5]triazin-4H-chromen-4-ones
14a(c-e) (Scheme 3). In this case 3-formylchromone 1 react as a usual aldehyde.14 N-
Arylimidodicarbonimidic diamides 15a-d and N,N-dimethylimidodicarbonimidic diamide 15e react
similar to N-1H-benzimidazol-2-ylguanidines 2c,d and N-1,3-benzoxazol-2-ylguanidine 2e forming 3-
(4,6-diamino-2,5-dihydro-1,3,5-triazin-2-yl)-4H-chromen-4-ones15 16(a-d)(a-e) (Scheme 3). It should be
noted that compound 16 have structure with exocyclic aniline fragment that was confirmed by NOESY
experiments on compound 16ab of this series.15

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HETEROCYCLES, Vol. 75, No. 3, 2008
R
O
X
R
N
N
O
R
R
N
c: R = H, X = NH (85%)
d: RR = O(CH2)3O, X = NH (81%)
e: R = H, X = O (74%)
1a
H
N
H2N
N
TMSCl, DMF
X
NH
2c-e
H2N
14a(c-e)
NH2
NH
NH2
NH
Cl
H
R''
O
O
N
R'
N
1a-f
O
O
N
H
N
R1
R'
TMSCl, DMF
N
N
NH
HN
N
N
H
Cl
R''
H2N
15a-e
a: R' = H, R'' = 2-OMeC6H4 (80%)
b: R' = H, R'' = 3,5-Cl2C6H3 (83%)
c: R' = H, R'' = 4-FC6H4 (71%)
d: R' = H, R'' = 3-Cl-4-FC6H3 (70%)
e: R' = R'' = Me (79%)
16aa, 16ab, 16cc, 16dd, 16be
16ab
NOESY
Scheme 3
The fact that N-(4-methylquinazolin-2-yl)guanidine 2f reacts with 3-formylchromone 1а on methyl group
forming N-{4-[(E)-2-(4-oxo-4H-chromen-3-yl)vinyl]quinazolin-2-yl}guanidine 17 appeared to be
surprising (Scheme 4). The similar product, namely stirile 19 is formed by the reaction of 3-
formylchromone 1а with 6-methyl-1,3,5-triazine-2,4-diamine 18.
O
N
NH
1a
O
N
HN
N
TMSCl, DMF
N
N
H
NH2
17 (72%)
2f
NH
H2N
O
H2N
N
1a
N
N
N
O
TMSCl, DMF
N
N
NH2
H2N
H2N
19 (67%)
18
Scheme 4
2-Amino-3,5-dihydro-4H-imidazol-4-one 20 does not react with 3-formylchromone 1a as 1,3-NCN-
binucleophiles but on methylene group forming 2-amino-5-[(4-oxo-4H-chromen-3-yl)methylene]-3,5-
dihydro-4H-imidazol-4-one 21 (Scheme 5).
O
O
N
HN
NH2
O
TMSCl, DMF
N
N
H
O
H2N
20
21 (81%)
Scheme 5

HETEROCYCLES, Vol. 75, No. 3, 2008
587
Table 1.
TMSCl promoted synthesis of 5-(2-hydroxybenzoyl)pyrimidines
Yield
Yield
(%)a
Entry
1
1
NCN-binucleophile Product
Entry
1
NCN-binucleophile Product
(%)a
O
OH
CN
O
OH
NH
N
N
N
1a
83
10
1a
76
71
NH2
Ph
NH2
NC
N
N
H
Ph
N
N
2a
3aa
10a
11aa
O
OH
O
OH
NH
CO2Et
N
N
EtO2C
N
N
NH2
N
N
2
3
1b
1b
72
88
11
12
1a
1a
NH2
N
N
N
H
10b
2b
3bb
11ab
O
OH
O
OH
N
N
N
N
CN
N
NC
N
NH2
N
93
90
N
N
H
N
N
NH2
N
N
N
H
4a
5ba
10c
11ac
O
OH
O
O
OH
N
N
N
N
N
CN
NC
O
N
F3C
NH2
N
N
H
N
N
4
5
1a
76
55
13
14
1a
1a
N
N
N
NH2
N
H
4b
F3C
5ab
10d
11ad
O
OH
N
O
HO
N
N
N
F
N
N
N
NC
N
NH2
N
O
N
H
HN
HN
CN
1d
95
OH
HO
N
NH2
4c
N
H
O
10e
12a
12b
5dc
11ae
O
OH
O
OH
NH2
N
N
N
N
N
Ph
NH2
N
N
N
N
6
7
1e
1f
90
81
15
16
1a
1a
91
86
H
N
N
Cl
N
H
4d
Ph
13aa
5ed
O
OH
O
OH
NH2
N
N
N
N
BnS
NH2
N
N
N
N
H
N
N
N
N
Br
N
H
4e
N
BnS
13ab
5fe
O
O
OH
OH
N
NH2
N
N
EtO2C
N
N
N
EtO2C
N
NH2
N
8
9
1b
1a
96
61
17
1a
89
N
H
N
N
O
N
H
H
O
H
6
12c
7b
O
13ac
OH
NC
N
N
N
N
NC
NH2
N
H
CN
NC
8
9a
aYields refer to pure isolated products
In summary, we have elaborated an efficient methodology for the preparation of 5-(2-
hydroxybenzoyl)pyrimidines and their heterofused analogues from 1,3-NCN-binucleophiles and 3-
formylchromones using chlorotrimethylsilane as a promoter and water scavenger. The methodology is

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HETEROCYCLES, Vol. 75, No. 3, 2008
applicable to a wide variety of amidines, guanidines and their heterocyclic analogues and delivers target
products in good yields.
EXPERIMENTAL
General Data: All chemicals were obtained from commercially available sources (Aldrich, Fluka,
Enamine Ltd.) and used without further purification. DMF was freshly distilled and dried by standard
methods; monitoring of water concentration in solvents (the solvent contained < 0.05%, usually 0.02% of
water) was performed using Mettler Toledo DL31 KF Titrator. All solvents for the crystallizations were
used without additional purification.
Melting points were measured with a Buchi melting points apparatus and are uncorrected. 1H NMR (400
MHz and 500 MHz) were recorded on a Varian Mercury-400 and Bruker Avance DRX-500
spectrometers with TMS as an internal standard. 13С NMR (125 MHz) were recorded on a Bruker Avance
DRX-500 spectrometer with TMS as an internal standard. NOESY experiments were recorded on a
Bruker Avance drx 500 spectrometer. LC/MS spectra were recorded using chromatography/mass
spectrometric system that consists of high-performance liquid chromatograph “Agilent 1100 Series”
equipped with diode-matrix and mass-selective detector “Agilent LC/MSD SL”. According to HPLC MS
data all the synthesized compounds have purity > 95%. IR spectra were recorded on a Nexus-470
spectrometer for samples in KBr discs. Microanalyses were performed in the Microanalytical Laboratory
of the Institute of Organic Chemistry, National Academy of Sciences of Ukraine. A Branson 2510E-MT
ultrasonic bath was used.
General procedure for the preparation of pyrimidines
An appropriate amidines 2a-f, 4a-e, 6, 8, 10a-e, 12a-c, 15a-e, 18, 20 (2 mmol) and an appropriate 3-
formylchromone 1a-f (2 mmol) were placed in 15 mL pressure tube and dissolved in DMF (3 mL).
Chlorotrimethylsilane (652 mg, 6 mmol) was added dropwise to the solution. The tube was thoroughly
sealed and heated on a water-bath for 6-12 h. After cooling the flask was opened (caution! Excessive
pressure inside); the reaction mixture was poured into water (15 mL) and allowed to stand at 20 °C in
ultrasonic bath for 1h. The precipitate formed was filtered and washed with small amount of i-PrOH (2
mL). Recrystallization from an appropriate solvent yielded the target compounds 3, 5, 7, 9, 11, 13, 14, 16,
17, 19, 21.
(2-Hydroxyphenyl)(2-phenylpyrimidin-5-yl)methanone (3aa)
1
Mp 131-132 °C (i-PrOH). H NMR (400 MHz, DMSO-d6) δ 7.01 (m, 2H, CH), 7.50-7.63 (m, 5H, CH),
8.47 (d, 3JHH = 8.2 Hz, 2H, CH), 9.11 (s, 2H, CH), 10.58 (s, 1H, OH). 13C NMR (125 MHz, DMSO-d6) δ
117.6, 120.1, 124.0, 128.9, 129.4, 129.5, 131.6, 132.4, 135.2, 136.8, 157.8, 158.4, 165.5, 194.0. IR (KBr):
ν = 3650-3200 (br, OH), 3070, 3030, 2926, 1626 (C=O), 1578, 1533, 1439, 1335, 1311, 1254, 1151, 933,

HETEROCYCLES, Vol. 75, No. 3, 2008
589
769, 752, 694. APSI MS: M++1 = 277. Anal. Calcd for C17H12N2O2: C, 73.90; H, 4.38; N, 10.14. Found:
C, 73.78; H, 4.49; N, 10.18.
(2-Hydroxy-5-methylphenyl)(2-pyrrolidin-1-ylpyrimidin-5-yl)methanone (3bb)
Mp 170-171 °C (i-PrOH). 1H NMR (500 MHz, DMSO-d6) δ 1.94 (m, 4H, 2CH2), 2.23 (s, 3H, CH3), 3.56
(m, 4H, 2NCH2), 6.85 (d, 3JHH = 8.4 Hz, 1H, CH), 7.15 (s, 1H, CH), 7.22 (d, 3JHH = 8.4 Hz, 1H, CH), 7.94
(s, 1H, CH), 8.59 (s, 1H, CH), 10.10 (br. s, 1H, OH). 13C NMR (125 MHz, DMSO-d6) δ 20.4, 25.3, 47.3,
117.1, 119.9, 124.8, 128.5, 130.6, 134.3, 154.7, 160.4, 160.5, 193.1. APSI MS: M++1 = 284. IR (KBr): ν
= 3650-3270 (br, OH), 3032, 2964, 2920, 1626 (C=O), 1587, 1541, 1485, 1331, 1290, 1234, 1144, 1109,
951, 806, 785, 613. Anal. Calcd for C16H17N3O2: C, 67.83; H, 6.05; N, 14.83. Found: C, 67.97; H, 5.91; N,
14.75.
(2-Hydroxy-5-methylphenyl)([1,2,4]triazolo[1,5-a]pyrimidin-6-yl)methanone (5ba)
Mp 180-181 °C (EtOH). 1H NMR (500 MHz, DMSO-d6) δ 2.26 (s, 3H, CH3), 6.92 (d, 3JHH = 8.2 Hz, 1H,
CH), 7.33 (d, 3JHH = 8.2 Hz, 1H, CH), 7.63 (s, 1H, CH), 8.83 (s, 1H, CH), 9.08 (d, 4JHH = 1.7 Hz, 1H, CH),
9.64 (d, 4JHH = 1.7 Hz, 1H, CH), 10.34 (s, 1H, OH). APSI MS: M++1 = 255. Anal. Calcd for C13H10N4O2:
C, 61.41; H, 3.96; N, 22.04. Found: C, 61.60; H, 3.84; N, 21.95.
(2-Hydroxyphenyl)[2-(trifluoromethyl)[1,2,4]triazolo[1,5-a]pyrimidin-6-yl]methanone (5ab)
Mp 169-170 °C (EtOH). 1H NMR (400 MHz, DMSO-d6) δ 7.03 (t, 3JHH = 8.0 Hz, 1H, CH), 7.17 (d, 3JHH
3
3
4
= 8.0 Hz, 1H, CH), 7.55 (d, JHH = 8.0 Hz, 1H, CH), 7.66 (t, JHH = 8.0 Hz, 1H, CH), 9.24 (d, JHH = 1.4
Hz, 1H, CH), 9.89 (d, 4JHH = 1.4 Hz, 1H, CH), 10.67 (br. s, 1H, OH). 13C NMR (125 MHz, DMSO-d6) δ
117.3 (q, 1JCF = 289.2 Hz), 117.8, 120.2, 123.0, 124.5, 129.1, 131.9, 135.5, 140.8 (q, 3JCF = 6.6 Hz), 152.4
(q, 2JCF = 38.9 Hz), 155.6, 158.1, 191.5. APSI MS: M++1 = 309. Anal. Calcd for C13H7F3N4O2: C, 50.66;
H, 2.29; N, 18.18. Found: C, 50.44; H, 2.40; N, 18.27.
(5-Fluoro-2-hydroxyphenyl)[2-(3-hydroxypropyl)[1,2,4]triazolo[1,5-a]pyrimidin-6-yl]methanone
(5dc)
1
3
Mp 170-171 °C (i-PrOH-hexane). H NMR (500 MHz, DMSO-d6) δ 1.93 (quintet, JHH = 6.8 Hz, 2H,
CH2), 2.90 (t, 3JHH = 6.8 Hz, 2H, NCH2), 3.46 (m, 1H, OH), 3.50 (m, 2H, OCH2), 7.02 (m, 1H, CH), 7.35
(m, 2H, CH), 9.03 (d, 4JHH = 2.3 Hz, 1H, CH), 9.58 (d, 4JHH = 2.3 Hz, 1H, CH), 10.42 (s, 1H, OH). APSI
MS: M++1 = 317. Anal. Calcd for C15H13FN4O3: C, 56.96; H, 4.14; N, 17.71. Found: C, 56.82; H, 4.26; N,
17.75.
(5-Chloro-2-hydroxyphenyl)(2-phenyl[1,2,4]triazolo[1,5-a]pyrimidin-6-yl)methanone (5ed)
Mp 244-245 °C (EtOH). 1H NMR (500 MHz, DMSO-d6) δ 7.04 (d, 3JHH = 8.3 Hz, 1H, CH), 7.52-7.56 (m,
4
4
2H, CH), 7.58 (m, 3H, CH), 8.24 (m, 2H, CH), 9.09 (d, JHH = 2.0 Hz, 1H, CH), 9.71 (d, JHH = 2.0 Hz,
1H, CH), 10.74 (s, 1H, OH). 13C NMR (125 MHz, DMSO-d6) δ 119.6, 121.9, 123.7, 125.8, 127.5, 129.5,

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HETEROCYCLES, Vol. 75, No. 3, 2008
129.6, 130.3, 131.7, 134.3, 140.2, 153.3, 155.9, 156.6, 167.1, 190.4. IR (KBr): ν = 3640-3300 (br, NH),
3057, 3026, 2962, 1616 (C=O), 1595, 1473, 1448, 1348, 1244, 1190, 930, 816, 719, 688. APSI MS:
M++1 = 351. Anal. Calcd for C18H11ClN4O2: C, 61.64; H, 3.16; Cl, 10.11; N, 15.97. Found: C, 61.50; H,
3.27; Cl, 10.15; N, 15.99.
[2-(Benzylthio)[1,2,4]triazolo[1,5-a]pyrimidin-6-yl](5-bromo-2-hydroxyphenyl)methanone (5fe)
Mp 225-226 °C (EtOH). 1H NMR (500 MHz, DMSO-d6) δ 4.60 (s, 2H, CH2), 6.75 (d, 3JHH = 8.3 Hz, 1H,
CH), 7.25 (d, 3JHH = 8.1 Hz, 2H, CH), 7.32 (t, 3JHH = 8.1 Hz, 2H, CH), 7.56 (s, 1H, CH), 7.58 (s, 1H, CH),
3
3
7.82 (d, JHH = 8.3 Hz, 1H, CH), 8.04 (t, JHH = 8.1 Hz, 1H, CH), 8.89 (s, 1H, CH), 9.34 (s, 1H, OH).
APSI MS: M++1 = 441. Anal. Calcd for C19H13BrN4O2S: C, 51.71; H, 2.97; Br, 18.11; N, 12.70; S, 7.27.
Found: C, 51.58; H, 3.09; Br, 18.19; N, 12.74; S, 7.33.
(2-Hydroxy-5-methylphenyl)(pyrimido[1,2-a]benzimidazol-3-yl)methanone (7b)
1
3
Mp 255-256 °C (EtOH-DMF). H NMR (400 MHz, DMSO-d6) δ 2.32 (s, 3H, CH3), 7.08 (d, JHH = 8.4
3
4
3
Hz, 1H, CH), 7.22-7.30 (m, 2H, CH), 7.44 (dd, JHH = 8.4 Hz, JHH = 2.0 Hz, 1H, CH), 7.51 (dd, JHH
8.4 Hz, 4JHH = 2.0 Hz, 1H, CH), 7.62-7.69 (m, 2H, CH), 8.97 (d, 4JHH = 1.2 Hz, 1H, CH), 9.89 (d, 4JHH
=
=
1.2 Hz, 1H, CH), 10.26 (br. s, 1H, OH). APSI MS: M++1 = 304. Anal. Calcd for C18H13N3O2: C, 71.28; H,
4.32; N, 13.85. Found: C, 71.10; H, 4.45; N, 13.93.
6-(2-Hydroxybenzoyl)imidazo[1,2-a]pyrimidine-2,3-dicarbonitrile (9a)
1
3
Mp 269-270 °C (i-PrOH). H NMR (400 MHz, DMSO-d6) δ 7.10 (d, JHH = 8.4 Hz, 1H, CH), 7.24 (t,
3JHH = 8.4 Hz, 1H, CH), 7.67 (t, 3JHH = 8.4 Hz, 1H, CH), 7.87 (d, 3JHH = 8.4 Hz, 1H, CH), 9.14 (d, 4JHH
=
4
1.4 Hz, 1H, CH), 9.42 (d, JHH = 1.4 Hz, 1H, CH), 10.73 (s, 1H, OH). APSI MS: M++1 = 290. Anal.
Calcd for C15H7N5O2: C, 62.29; H, 2.44; N, 24.21. Found: C, 62.13; H, 2.62; N, 24.13.
6-(2-Hydroxybenzoyl)pyrazolo[1,5-a]pyrimidine-3-carbonitrile (11aa)
Mp 155-156 °C (i-PrOH). 1H NMR (500 MHz, DMSO-d6) δ 7.01 (m, 2H, CH), 7.52 (t, 3JHH = 8.0 Hz, 1H,
CH), 7.56 (d, 3JHH = 8.0 Hz, 1H, CH), 8.97 (s, 1H, CH), 9.03 (d, 4JHH = 1.4 Hz, 1H, CH), 9.57 (d, 4JHH
=
1.4 Hz, 1H, CH), 10.58 (s, 1H, OH). 13C NMR (125 MHz, DMSO-d6) δ 82.6, 113.3, 117.7, 120.2, 122.7,
123.9, 131.7, 135.3, 140.5, 150.3, 150.6, 154.2, 157.7, 191.7. IR (KBr): ν = 3640-3280 (br, OH), 3097,
3037, 2904, 2227 (C≡N), 1674 (C=O), 1585, 1522, 1462, 1373, 1333, 1271, 1215, 1138, 1009, 891, 768.
APSI MS: M++1 = 265. Anal. Calcd for C14H8N4O2: C, 63.64; H, 3.05; N, 21.20. Found: C, 63.50; H,
3.18; N, 21.23.
Ethyl 6-(2-hydroxybenzoyl)pyrazolo[1,5-a]pyrimidine-3-carboxylate (11ab)
Mp 156-157 °C (i-PrOH-hexane). 1H NMR (500 MHz, DMSO-d6) δ 1.30 (t, 3JHH = 7.0 Hz, 3H, CH2CH3),
3
3
4.29 (m, 2H, CH2CH3), 7.01 (m, 2H, CH), 7.52 (t, JHH = 8.0 Hz, 1H, CH), 7.56 (d, JHH = 8.0 Hz, 1H,
4
4
CH), 8.78 (s, 1H, CH), 9.02 (d, JHH = 1.5 Hz, 1H, CH), 9.45 (d, JHH = 1.5 Hz, 1H, CH), 10.79 (s, 1H,

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591
OH). APSI MS: M++1 = 312. Anal. Calcd for C16H13N3O4: C, 61.73; H, 4.21; N, 13.50. Found: C, 61.89;
H, 4.05; N, 13.44.
6-(2-Hydroxybenzoyl)-2-pyrrolidin-1-ylpyrazolo[1,5-a]pyrimidine-3-carbonitrile (11ac)
1
Mp 173-174 °C (EtOH-DMF). H NMR (500 MHz, DMSO-d6) δ 1.97 (m, 4H, 2CH2), 3.57 (m, 4H,
2NCH2), 6.99 (m, 2H, CH), 7.48 (m, 2H, CH), 8.74 (d, 4JHH = 1.0 Hz, 1H, CH), 9.08 (d, 4JHH = 1.0 Hz, 1H,
CH), 10.45 (s, 1H, OH). APSI MS: M++1 = 334. Anal. Calcd for C18H15N5O2: C, 64.86; H, 4.54; N, 21.01.
Found: C, 64.68; H, 4.65; N, 21.08.
6-(2-Hydroxybenzoyl)-2-morpholin-4-ylpyrazolo[1,5-a]pyrimidine-3-carbonitrile (11ad)
1
3
Mp 183-184 °C (EtOH-DMF). H NMR (400 MHz, DMSO-d6) δ 3.59 (t, JHH = 5.0 Hz, 4H, 2NCH2),
3.76 (t, 3JHH = 5.0 Hz, 4H, 2OCH2), 6.96-7.03 (m, 2H, CH), 7.49 (m, 2H, CH), 8.81 (d, 4JHH = 0.8 Hz, 1H,
4
13
CH), 9.15 (d, JHH = 0.8 Hz, 1H, CH), 10.50 (s, 1H, OH). C NMR (125 MHz, DMSO-d6) δ 46.9, 65.9,
68.9, 114.7, 117.6, 120.1, 121.4, 124.2, 131.4, 134.8, 138.4, 152.6, 153.1, 157.2, 162.3, 191.6. IR (KBr):
ν = 3650-3280 (br, OH), 3084, 2987, 2968, 2926, 2220 (C≡N), 1620 (C=O), 1578, 1481, 1448, 1335,
1252, 1157, 1113, 993, 866, 812, 760, 658. APSI MS: M++1 = 350. Anal. Calcd for C18H15N5O3: C,
61.89; H, 4.33; N, 20.05. Found: C, 61.98; H, 4.20; N, 20.11.
6-(2-Hydroxybenzoyl)-2-[(4-methoxyphenyl)amino]pyrazolo[1,5-a]pyrimidine-3-carbonitrile (11ae)
Mp 232-233 °C (EtOH-DMF). 1H NMR (400 MHz, DMSO-d6) δ 3.73 (s, 3H, OCH3), 6.91 (d, 3JHH = 8.2
3
4
Hz, 2H, CH), 7.01 (m, 2H, CH), 7.50 (m, 2H, CH), 7.63 (d, JHH = 8.2 Hz, 2H, CH), 8.82 (d, JHH = 1.7
4
Hz, 1H, CH), 9.17 (d, JHH = 1.7 Hz, 1H, CH), 9.58 (s, 1H, NH), 10.49 (s, 1H, OH). APSI MS: M++1 =
386. Anal. Calcd for C21H15N5O3: C, 65.45; H, 3.92; N, 18.17. Found: C, 65.31; H, 4.03; N, 18.25.
(2-Hydroxyphenyl)(pyrimido[1,2-b]indazol-3-yl)methanone (13aa)
Mp 160-161 °C (EtOH). 1H NMR (400 MHz, DMSO-d6) δ 7.04 (m, 2H, CH), 7.36 (t, 3JHH = 8.5 Hz, 1H,
3
3
3
CH), 7.54 (t, JHH = 7.8 Hz, 1H, CH), 7.60 (d, JHH = 7.8 Hz, 1H, CH), 7.70 (t, JHH = 8.5 Hz, 1H, CH),
7.85 (d, 3JHH = 8.5 Hz, 1H, CH), 8.28 (d, 3JHH = 8.5 Hz, 1H, CH), 8.96 (d, 4JHH = 1.9 Hz, 1H, CH), 9.56 (d,
4JHH = 1.9 Hz, 1H, CH), 10.54 (s, 1H, OH). 13C NMR (125 MHz, DMSO-d6) δ 113.0, 116.8, 117.7, 120.1,
121.2, 122.1, 123.5, 124.3, 131.1, 131.6, 135.1, 137.4, 143.8, 146.3, 152.8, 157.6, 192.8. IR (KBr): ν =
3650-3140 (br, OH), 3057, 1641 (C=O), 1624, 1581, 1502, 1479, 1443, 1377, 1333, 1306, 1248, 1219,
1178, 1155, 1119, 1022, 881, 758, 723. APSI MS: M++1 = 290. Anal. Calcd for C17H11N3O2: C, 70.58; H,
3.83; N, 14.52. Found: C, 70.45; H, 3.96; N, 14.47.
(2-Hydroxyphenyl)(pyrido[2’,3’:3,4]pyrazolo[1,5-a]pyrimidin-3-yl)methanone (13ab)
Mp 234-235 °C (EtOH). 1H NMR (400 MHz, DMSO-d6) δ 7.04 (m, 2H, CH), 7.40 (m, 1H, CH), 7.55 (t,
3
3
3JHH = 7.9 Hz, 1H, CH), 7.61 (d, JHH = 7.9 Hz, 1H, CH), 8.76 (d, JHH = 8.5 Hz, 1H, CH), 8.97 (m, 1H,
CH), 9.05 (d, 4JHH = 2.0 Hz, 1H, CH), 9.66 (d, 4JHH = 2.0 Hz, 1H, CH), 10.59 (s, 1H, OH). 13C NMR (125

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MHz, DMSO-d6) δ 106.2, 118.0, 118.4, 120.5, 124.4, 124.7, 131.5, 132.0, 135.6, 138.3, 143.5, 148.1,
156.0, 158.0, 161.7, 192.8. IR (KBr): ν = 3650-3100 (br, OH), 3074, 3030, 2924, 1633 (C=O), 1620,
1585, 1485, 1400, 1338, 1296, 1246, 1157, 816, 775. APSI MS: M++1 = 291. Anal. Calcd for
C16H10N4O2: C, 66.20; H 3.47; N 19.30. Found: C, 66.32; H, 3.40; N, 19.21.
Ethyl
3-(2-hydroxybenzoyl)-8-oxo-7,8-dihydropyrido[2’,3’:3,4]pyrazolo[1,5-a]pyrimidine-9-
carboxylate (13ac)
1
3
Mp 291-292 °C (DMF-MeOH). H NMR (400 MHz, DMSO-d6) δ 1.30 (t, JHH = 7.1 Hz, 3H, CH2CH3),
4.24 (q, 3JHH = 7.1 Hz, 2H, CH2CH3), 6.98-7.06 (m, 2H, CH), 7.53 (m, 2H, CH), 8.63 (s, 1H, CH), 8.93 (d,
4JHH = 1.8 Hz, 1H, CH), 9.44 (d, 4JHH = 1.8 Hz, 1H, CH), 10.54 (s, 1H, OH), 12.56 (s, 1H, NH). 13C NMR
(125 MHz, DMSO-d6) δ 14.6, 60.9, 95.3, 117.6, 118.1, 120.1, 122.2, 124.2, 131.5, 135.0, 136.6, 139.5,
145.1, 151.7, 156.0, 157.4, 160.7, 164.6, 191.8. IR (KBr): ν = 3454 (br, OH, NH), 3064, 3018, 2985,
2962, 1740 (C=Oester), 1674, 1649, 1624, 1605, 1518, 1483, 1450, 1425, 1340, 1308, 1250, 1211, 1153,
1074, 903, 800, 766, 675. APSI MS: M++1 = 379. Anal. Calcd for C19H14N4O5: C, 60.32; H, 3.73; N,
14.81. Found: C, 60.49; H, 3.60; N, 14.85.
3-(2-Amino-4,10-dihydro[1,3,5]triazino[1,2-a]benzimidazol-4-yl)-4H-chromen-4-one (14ac)
Mp 295-296 °C (EtOH-DMF). 1H NMR (400 MHz, DMSO-d6) δ 6.89 (s, 1H, CH), 7.15 (t, 3JHH = 7.8 Hz,
3
3
3
1H, CH), 7.22 (t, JHH = 7.8 Hz, 1H, CH), 7.31 (d, JHH = 7.8 Hz, 1H, CH), 7.35 (d, JHH = 7.8 Hz, 1H,
CH), 7.50 (t, 3JHH = 8.5 Hz, 1H, CH), 7.64 (br. s, 2H, NH2), 7.72 (d, 3JHH = 8.5 Hz, 1H, CH), 7.85 (t, 3JHH
3
13
= 8.5 Hz, 1H, CH), 7.96 (d, JHH = 8.5 Hz, 1H, CH), 8.95 (s, 1H, CH), 13.07 (br. s, 1H, NH). C NMR
(125 MHz, DMSO-d6) δ 62.6, 110.8, 112.0, 119.2, 119.4, 123.3, 124.0, 124.2, 125.3, 126.7, 128.0, 129.6,
135.5, 151.6, 156.1, 157.5, 158.3, 175.3. IR (KBr): ν = 3383 (NH), 3140 (br, NH), 2987, 2929, 1687,
1655, 1606, 1527, 1466, 1363, 1296, 762, 634. APSI MS: M++1 = 332. Anal. Calcd for C18H13N5O2: C,
65.25; H, 3.95; N, 21.14. Found: C, 65.11; H, 4.11; N, 21.06.
3-(2-Amino-4,9,10,13-tetrahydro-8H-[1,4]dioxepino[2,3-f][1,3,5]triazino[1,2-a]benzimidazol-4-yl)-
4H-chromen-4-one (14ad)
Mp >300 °C (EtOH-DMF). 1H NMR (500 MHz, DMSO-d6) δ 2.02 (m, 2H, CH2), 4.02 (m, 4H, 2OCH2),
6.73 (s, 1H, CH), 6.93 (d, 4JHH = 1.7 Hz, 1H, CH), 6.99 (d, 4JHH = 1.7 Hz, 1H, CH), 7.31 (br. s, 1H, NH),
7.50 (t, 3JHH = 8.3 Hz, 1H, CH), 7.72 (d, 3JHH = 8.3 Hz, 1H, CH), 7.84 (t, 3JHH = 8.3 Hz, 1H, CH), 7.96 (d,
3JHH = 8.3 Hz, 1H, CH), 8.76 (s, 1H, NH), 8.91 (s, 1H, CH), 12.88 (br. s, 1H, NH). 13C NMR (125 MHz,
DMSO-d6) δ 32.3, 62.6, 71.57, 71.62, 104.0, 105.0, 119.2, 119.3, 123.7, 124.1, 125.3, 125.4, 126.7, 135.6,
148.6, 149.3, 152.1, 156.2, 157.2, 158.2, 175.3. APSI MS: M++1 = 404. Anal. Calcd for C21H17N5O4: C,
62.53; H, 4.25; N, 17.36. Found: C, 62.65; H, 4.14; N, 17.31.

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3-(2-Amino-4H-[1,3,5]triazino[2,1-b][1,3]benzoxazol-4-yl)-4H-chromen-4-one (14ae)
1
Mp 257-258 °C (EtOH-DMF). H NMR (500 MHz, DMSO-d6) δ 6.93 (s, 1H, CH), 7.32 (m, 2H, CH),
3
3
7.39 (m, 1H, CH), 7.51 (t, JHH = 8.3 Hz, 1H, CH), 7.70 (m, 1H, CH), 7.75 (d, JHH = 8.3 Hz, 1H, CH),
7.86 (t, 3JHH = 8.3 Hz, 1H, CH), 7.97 (d, 3JHH = 8.3 Hz, 1H, CH), 8.74 (s, 1H, NH), 9.05 (s, 1H, CH), 9.64
13
(s, 1H, NH). C NMR (125 MHz, DMSO-d6) δ 63.7, 110.6, 111.6, 118.1, 119.4, 120.5, 123.8, 125.3,
125.8, 126.9, 127.2, 135.7, 144.1, 156.2, 158.2, 159.3, 164.0, 175.4. IR (KBr): ν = 3346 (NH), 3238 (NH),
3128, 2968, 2929, 1678, 1649, 1614, 1508, 1460, 1365, 1313, 1173, 1078, 827, 773, 741. APSI MS:
M++1 = 333. Anal. Calcd for C18H12N4O3: C, 65.06; H, 3.64; N, 16.86. Found: C, 64.92; H, 3.81; N,
16.79.
3-{4-Amino-6-[(2-methoxyphenyl)amino]-2,5-dihydro-1,3,5-triazin-2-yl}-4H-chromen-4-one (16aa)
1
Mp 259-260 °C (EtOH). H NMR (400 MHz, DMSO-d6) δ 3.91 (s, 3H, OCH3), 5.75 (s, 1H, CH), 6.81-
7.09 (m, 2H, CH), 7.20 (d, 3JHH = 8.2 Hz, 1H, CH), 7.30 (br. s, 1H, NH), 7.37 (t, 3JHH = 8.2 Hz, 1H, CH),
7.54 (t, 3JHH = 8.2 Hz, 1H, CH), 7.64 (d, 3JHH = 8.2 Hz, 1H, CH), 7.83 (t, 3JHH = 8.2 Hz, 1H, CH), 8.07 (d,
3JHH = 8.2 Hz, 1H, CH), 8.13 (br. s, 1H, NH), 8.38 (s, 1H, CH), 8.86 (br. s, 2H, NH). 13C NMR (125 MHz,
DMSO-d6) δ 56.6, 65.1, 113.7, 119.0, 120.7, 121.6, 124.0, 124.8, 125.5, 126.6, 130.2, 131.0, 131.6, 135.3,
155.4, 156.0, 157.4, 157.8, 175.3. APSI MS: M++1 = 364. Anal. Calcd for C19H17N5O3: C, 62.80; H,
4.72; N, 19.27. Found: C, 62.93; H, 4.61; N, 19.21.
3-{4-Amino-6-[(3,5-dichlorophenyl)amino]-2,5-dihydro-1,3,5-triazin-2-yl}-4H-chromen-4-one
(16ab)
Mp 266-267 °C (MeOH). 1H NMR (400 MHz, DMSO-d6) δ 5.99 (s, 1H, CH), 7.31 (t, 4JHH = 2.0 Hz, 1H,
CH), 7.45 (br. s, 1H, NH), 7.56 (t, 3JHH = 8.3 Hz, 1H, CH), 7.66 (d, 4JHH = 2.0 Hz, 2H, CH), 7.73 (d, 3JHH
= 8.3 Hz, 1H, CH), 7.88 (td, 3JHH = 8.3 Hz, 4JHH = 1.5 Hz, 1H, CH), 8.10 (dd, 3JHH = 8.3 Hz, 4JHH = 1.5 Hz,
1H, CH), 8.17 (br. s, 1H, NH), 8.48 (s, 1H, CH), 8.71 (s, 1H, NH), 8.88 (s, 1H, NH). 13C NMR (125 MHz,
DMSO-d6) δ 58.6, 119.1, 119.7, 122.5, 123.4, 123.9, 125.4, 126.6, 134.5, 135.4, 140.8, 155.5, 156.0,
156.3, 158.0, 175.8. IR (KBr): ν = 3367 (NH), 3153 (NH), 3089, 3026, 2976, 1647, 1620, 1599, 1572,
1556, 1531, 1466, 1406, 1315, 764. APSI MS: M++1 = 402. APSI MS: M++1 = 364. Anal. Calcd for
C18H13Cl2N5O2: C, 53.75; H, 3.26; Cl, 17.63; N, 17.41. Found: C, 53.88; H, 3.40; Cl, 17.52; N, 17.37.
3-{4-Amino-6-[(4-fluorophenyl)amino]-2,5-dihydro-1,3,5-triazin-2-yl}-6-methoxy-4H-chromen-4-
one (16cc)
Mp 272-273 °C (EtOH). 1H NMR (400 MHz, DMSO-d6) δ 3.87 (s, 3H, OCH3), 5.95 (s, 1H, CH), 7.18 (t,
3JHF = 9.0 Hz, 2H, CH), 7.35 (br. s, 1H, NH), 7.45-7.49 (m, 2H, CH), 7.55 (m, 2H, CH), 7.70 (m, 1H,
13
CH), 8.43 (s, 1H, CH), 8.53 (s, 1H, NH), 8.75 (s, 1H, NH), 10.11 (s, 1H, NH). C NMR (125 MHz,
2
3
DMSO-d6) δ 56.3, 58.6, 105.2, 115.9 (d, JCF = 22.1 Hz), 120.8, 121.9, 124.4 (d, JCF = 7.5 Hz), 124.5,

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124.6, 134.2, 151.1, 152.0, 155.6, 155.7, 156.5 (d, 1JCF = 238.4 Hz), 158.2, 175.6. APSI MS: M++1 = 382.
Anal. Calcd for C19H16FN5O3: C, 59.84; H, 4.23; N, 18.36. Found: C, 60.01; H, 4.09; N, 18.30.
3-{4-Amino-6-[(3-chloro-4-fluorophenyl)amino]-2,5-dihydro-1,3,5-triazin-2-yl}-6-fluoro-4H-
chromen-4-one (16dd)
Mp 273-274 °C (EtOH). 1H NMR (500 MHz, DMSO-d6) δ 5.96 (s, 1H, CH), 7.37 (m, 1H, CH), 7.43 (m,
1H, CH), 7.78 (m, 2H, CH), 7.84 (m, 2H, CH), 8.03 (br. s, 1H, NH), 8.49 (s, 1H, CH), 8.62 (s, 1H, NH),
13
2
8.83 (s, 1H, NH), 10.33 (s, 1H, NH). C NMR (125 MHz, DMSO-d6) δ 58.5, 110.0 (d, JCF = 23.9 Hz),
3
116.9 (d, 2JCF = 22.6 Hz), 117.3 (d, 2JCF = 22.2 Hz), 119.8 (d, 2JCF = 18.6 Hz), 121.4, 122.0 (d, JCF = 9.2
Hz), 122.4 (d, 3JCF = 8.4 Hz), 123.4, 123.7 (d, 3JCF = 7.1 Hz), 125.1 (d, 3JCF = 6.2 Hz), 135.3, 152.8, 154.3
(d, 1JCF = 243.2 Hz), 155.6, 157.2 (d, 1JCF = 242.4 Hz), 166.4, 175.2. APSI MS: M++1 = 404. Anal. Calcd
for C18H12ClF2N5O2: C, 53.54; H, 3.00; Cl, 8.78; N, 17.34. Found: C, 53.72; H, 3.11; Cl, 8.67; N, 17.27.
3-[4-Amino-6-(dimethylamino)-2,5-dihydro-1,3,5-triazin-2-yl]-6-methyl-4H-chromen-4-one (16be)
Mp 232-233 °C (EtOH). 1H NMR (400 MHz, DMSO-d6) δ 2.44 (s, 3H, CH3), 3.04 (s, 6H, N(CH3)2), 5.84
(s, 1H, CH), 7.28 (br. s, 1H, NH), 7.61 (d, 3JHH = 8.5 Hz, 1H, CH), 7.68 (dd, 3JHH = 8.5 Hz, 4JHH = 1.7 Hz,
4
13
1H, CH), 7.87 (d, JHH = 1.7 Hz, 1H, CH), 8.35 (s, 1H, CH), 8.43 (s, 1H, NH), 8.54 (s, 1H, NH). C
NMR (125 MHz, DMSO-d6) δ 21.0, 37.4, 58.2, 118.9, 122.4, 123.6, 124.6, 136.1, 136.3, 154.6, 155.6,
156.4, 157.8, 175.8. IR (KBr): ν = 3311 (br, NH), 1682, 1632, 1481, 1354, 1292, 1171, 1117, 1063, 833,
802. APSI MS: M++1 = 300. Anal. Calcd for C15H17N5O2: C, 60.19; H, 5.72; N, 23.40. Found: C, 60.33;
H, 5.57; N, 23.29.
N-{4-[(E)-2-(4-Oxo-4H-chromen-3-yl)vinyl]quinazolin-2-yl}guanidine hydrochloride (17)
Mp 259-260 °C (MeCN). 1H NMR (500 MHz, DMSO-d6) δ 7.56 (t, 3JHH = 8.1 Hz, 1H, CH), 7.69 (m, 1H,
3
3
3
CH), 7.74 (d, JHH = 8.1 Hz, 1H, CH), 7.86 (t, JHH = 8.1 Hz, 1H, CH), 7.99 (s, 2H, CH), 8.09 (d, JHH
=
15.4 Hz, 1H, CH), 8.17 (d, 3JHH = 8.1 Hz, 1H, CH), 8.44 (br. s, 4H, NH), 8.47 (d, 3JHH = 8.1 Hz, 1H, CH),
8.66 (d, 3JHH = 15.4 Hz, 1H, CH), 9.14 (s, 1H, CH), 11.07 (br. s, 1H, NH). 13C NMR (125 MHz, DMSO-
d6) δ 119.0, 119.6, 120.2, 121.7, 123.8, 125.4, 125.9, 126.6, 127.1, 127.3, 132.3, 135.1, 135.8, 150.5,
153.9, 155.7, 156.0, 159.5, 164.9, 175.8. IR (KBr): ν = 3277 (br, NH), 3047, 2929, 1697, 1655, 1630,
1612, 1541, 1500, 1466, 1319, 775, 760. APSI MS: M++1 = 358. Anal. Calcd for C20H16ClN5O2: C,
61.00; H, 4.09; Cl, 9.00; N, 17.78. Found: C, 61.16; H, 3.97; Cl, 8.88; N, 17.72.
3-[(E)-2-(4,6-Diamino-1,3,5-triazin-2-yl)vinyl]-4H-chromen-4-one (19)
Mp 243-244 °C (EtOH). 1H NMR (500 MHz, DMSO-d6) δ 7.54 (t, 3JHH = 8.5 Hz, 1H, CH), 7.68 (d, 3JHH
3
3
3
= 15.6 Hz, 1H, CH), 7.75 (d, JHH = 8.5 Hz, 1H, CH), 7.81 (d, JHH = 15.6 Hz, 1H, CH), 7.88 (td, JHH
=
4
3
4
8.5 Hz, JHH = 1.5 Hz, 1H, CH), 7.89 (br. s, 2H, NH2), 8.17 (dd, JHH = 8.5 Hz, JHH = 1.5 Hz, 1H, CH),
13
8.31 (br. s, 2H, NH2), 8.90 (s, 1H, CH). C NMR (125 MHz, DMSO-d6) δ 118.9, 119.0, 124.0, 125.5,

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126.0, 126.6, 134.1, 135.1, 155.6, 160.4, 162.8, 163.5, 175.8. IR (KBr): ν = 3354 (NH), 3319 (NH), 3151,
3078, 1686, 1649, 1630, 1578, 1460, 1348, 1300, 978, 791, 758, 704. APSI MS: M++1 = 282. Anal.
Calcd for C14H11N5O2: C, 59.78; H, 3.94; N, 24.90. Found: C, 59.98; H, 3.81; N, 24.78.
2-Amino-5-[(4-oxo-4H-chromen-3-yl)methylene]-3,5-dihydro-4H-imidazol-4-one (21)
Mp >300 °C. 1H NMR (500 MHz, DMSO-d6) δ 6.33 (s, 1H, CH), 7.52 (t, 3JHH = 8.3 Hz, 1H, CH), 7.68 (d,
3JHH = 8.3 Hz, 1H, CH), 7.74 (br. s, 2H, NH2), 7.83 (t, 3JHH = 8.3 Hz, 1H, CH), 8.12 (d, 3JHH = 8.3 Hz, 1H,
13
CH), 9.24 (s, 1H, CH), 10.77 (br. s, 1H, NH). C NMR (125 MHz, DMSO-d6) δ 100.5, 119.0, 119.1,
120.0, 123.4, 125.9, 126.4, 135.1, 155.9, 159.1, 161.0, 171.1, 175.9. IR (KBr): ν = 3396 (br, NH), 3219
(NH), 3153, 3021, 2927, 1707, 1660, 1632, 1612, 1558, 1464, 1387, 1252, 1144, 764. APSI MS: M++1 =
256. Anal. Calcd for C13H9N3O3: C, 61.18; H, 3.55; N, 16.46. Found: C, 61.07; H, 3.69; N, 16.40.
ACKNOWLEDGEMENTS
The authors acknowledge S. A. Alekseev (Department of Chemistry of Kyiv National Taras Shevchenko
University) and V. V. Polovinko (“Enamine Ltd.”) for spectral measurements and D. Dontsova for
helpful discussions upon preparation of the manuscript.
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