Synthesis and reactions of 2-amino-6-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-phenylpyridine-3- carbonitrile

Article abstract of DOI:10.1002/jhet.5570390211

2-Amino-6-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-phenylpyridine-3- carbonitrile (1) obtained by the reaction of 4-(1-iminoethyl)-3-methyl-1-phenyl-2-pyrazolin-5-one with benzylidenemalononitrile, was reacted with triethyl orthoformate followed by hydrazine hydrate, acetic anhydride, acetyl chloride, alkyl halides, benzoyl chloride, sulphuric acid followed by formamide, phenyl isothiocyanate, carbon disulphide followed by ethyl iodide, formamide, trichloroacetonitrile, nitrous acid, giving new oxopyrazolinylpyridines (2,3,5,6,8,9,10) and related pyridopyrimidines (11-17) and pyridotriazine (18).

Full text of DOI:10.1002/jhet.5570390211

Mar-Apr 2002
Synthesis and Reactions of 2-Amino-6-(3-methyl-5-oxo-1-phenyl-2-
pyrazolin-4-yl)-4-phenylpyridine-3-carbonitrile [1]
309
R. A. Ahmed, M. M. Kandeel, M. S. Abbady and M. S. K. Youssef*
Department of Chemistry, Faculty of Science, Assiut University, Assiut, Egypt.
Received June 25, 2001
2-Amino-6-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-phenylpyridine-3-carbonitrile (1) obtained by
the reaction of 4-(1-iminoethyl)-3-methyl-1-phenyl-2-pyrazolin-5-one with benzylidenemalononitrile, was
reacted with triethyl orthoformate followed by hydrazine hydrate, acetic anhydride, acetyl chloride, alkyl
halides, benzoyl chloride, sulphuric acid followed by formamide, phenyl isothiocyanate, carbon disulphide
followed by ethyl iodide, formamide, trichloroacetonitrile, nitrous acid, giving new oxopyrazolinylpyridines
(2,3,5,6,8,9,10) and related pyridopyrimidines (11-17) and pyridotriazine (18).
J. Heterocyclic Chem., 39, 309 (2002).
As a continuation of our previous work [2,3] about the
The o-aminonitrile function of 1 was exploited to synthe-
size some new oxopyrazolinylpyridines and related pyri-
dopyrimidines and pyridotriazine. Thus, the reaction of 1
with excess triethyl orthoformate led to the formation of 2-
(ethoxymethyleneamino)-6-(3-methyl-5-oxo-1-phenyl-2-
pyrazolin-4-yl)-4-phenylpyridine-3-carbonitrile (2), whose
reaction with hydrazine hydrate gave 2-(hydrazinomethyle-
neamino)-6-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-
4-phenylpyridine-3-carbonitrile (3). Attempts to cyclize 3
by refluxing in ethanol containing piperidine and/or pyri-
dine to afford 4 were unsuccessful.
chemistry of 5-pyrazolone derivatives and their wide
applications in different industrial, biological and medici-
nal fields [4-6], we report in this paper the synthesis of
oxopyrazolinylpyridines and some related pyridopyrim-
idines and pyridotriazine. For this purpose 2-amino-6-(3-
methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-phenylpyri-
dine-3-carbonitrile (1) was prepared by the reaction of 4-
(1-iminoethyl)-3-methyl-1-phenyl-2-pyrazolin-5-one [7]
with benzylidenemalononitrile in ethanol in the presence
of piperidine as a catalyst (Scheme 1).
The reaction of compound 1 with acetic anhydride pro-
vided two products, which were identified as 2-acety-
lamino-6-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-
phenylpyridine-3-carbonitrile (5) and 2-diacetylamino-6-
(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-phenyl-
pyridine-3-carbonitrile (6), however the cyclized com-
pound 7 was not obtained.
Scheme 1
Compound 5 was also prepared by an alternative route
via the reaction of 1 with acetyl chloride in the presence of
pyridine as a catalyst (Scheme 2).
Scheme 2

310
R. A. Ahmed, M. M. Kandeel, M. S. Abbady and M. S. K. Youssef
Vol. 39
Treatment of 1 with benzylchloride or ethyl chloroac-
yl]benzamide (9). Moreover, hydrolysis of 1 with con-
centrated sulphuric acid gave 2-amino-6-(3-methyl-5-
oxo-1-phenyl-2-pyrazolin-4-yl)-4-phenylpyridine-3-car-
boxamide (10). Treatment of 10 with formamide
afforded 7-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-
5-phenylpyrido[2,3-d]-pyrimidin-4(3H)-one (11), while
the reaction of 1 with phenyl isothiocyanate in pyridine
provided 4-phenylamino-7-(3-methyl-5-oxo-1-phenyl-2-
etate led to the formation of 2-(benzylamino)-6-(3-
methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-phenylpyri-
dine-3-carbonitrile (8a) or ethyl 2-[3-cyano-6-(3-methyl-
5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-phenylpyridin-2-
yl]aminoacetate (8b) respectively, while benzoylation of
the amino group of 1 produced N-[3-cyano-6-(3-methyl-
5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-phenylpyridin-2-
Scheme 3
Scheme 4

Mar-Apr 2002
Synthesis and Reactions of 2-Amino-6-(3-methyl-5-oxo-1-phenyl-
2-pyrazolin-4-yl)-4-phenylpyridine-3-carbonitrile
311
pyrazolin-4-yl)-5-phenylpyrido[2,3-d]pyrimidine-2(1H)-
thione (12) (Scheme 3).
phenyl-2-pyrazolin-4-yl)-5-phenylpyrido[2,3-d]pyrimi-
dine (16). The trichloromethyl moiety in 16 could be sub-
stituted by hydroxyl group on refluxing with aqueous
sodium hydroxide solution and by ethoxy group on boiling
with sodium ethoxide in ethanol solution giving 4-amino-
2-(hydroxy)- and 2-(ethoxy)-7-(3-methyl-5-oxo-1-phenyl-
2-pyrazolin-4-yl)-5-phenylpyrido[2,3-d]pyrimidines
(17a,b) respectively. Reaction of nitrous acid with 1 under
ordinary conditions afforded 4-chloro-7-(3-methyl-5-oxo-
1-phenyl-2-pyrazolin-4-yl)-5-phenylpyrido[2,3-d][1,2,3]-
triazine (18) (Scheme 4).
Carbon disulphide reacted with 1 in alcoholic sodium
hydroxide solution to give 7-(3-methyl-5-oxo-1-phenyl-2-
pyrazolin-4-yl)-5-phenylpyrido[2,3-d]pyrimidine-
2,4(1H,3H)-dithione (13), which on subsequent alkylation
with ethyl iodide afforded 2,4-bis(ethylmercapto)-7-(3-
methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-5-phenylpyrido-
[2,3-d]pyrimidine (14), while reaction of 1 with formamide
gave 4-amino-7-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-
yl)-5-phenylpyrido[2,3-d]pyrimidine (15).
Also, reaction of trichloroacetonitrile with 1 in refluxing
toluene in the presence of a catalytic amount of piperidine
yields 4-amino-2-trichloromethyl-7-(3-methyl-5-oxo-1-
The structures of new compounds were confirmed on
the basis of elemental analyses as well as spectral data (IR,
H-NMR and MS).
1
Table I
Physical Properties and Elemental Analyses of the Prepared Compounds

312
R. A. Ahmed, M. M. Kandeel, M. S. Abbady and M. S. K. Youssef
Vol. 39
-1
EXPERIMENTAL
Compound 5 has IR (KBr): υ 3250 cm (NH), 2200 (C≡N),
1
1700 (C=O of acetyl group), 1600 (C=O) of pyrazolone); H-
NMR (DMSO-d ): δ 2.69 (s, 3H, CH ), 2.94 (s, 3H, COCH ),
All melting points are uncorrected. The IR spectra were run on
a pye-unicam SP 3-100 spectrophotometer using KBr disc tech-
6
3
3
7.72 (s, 1H, H-4, pyrazolone), 7.42-8.14 (m, 10H, arom-H), 8.27
(s, 1H, pyridine), 11.24 (s, 1H, NH); MS, m/z (%): 410 (29), 409
-1
1
nique (ν
in cm ). H-NMR spectra were recorded on JNM-
amx
+
(M , 100), 368 (24), 367 (92).
Compound 6 has IR (KBr): υ 2220 cm (C≡N), 1720 (C=O)
FT 400-lambda series, chemical shifts are given in ppm (δ-scale),
and MS spectra were run on JEOL JMS 600 spectrophotometer.
Yields, melting points, and analytical data of all reported com-
pounds are given in Table I.
-1
1
of (COCH ) , 1680 (C=O of pyrazolone); H-NMR (CDCl ): δ
3 2
3
2.40 (s, 6H, N(COCH ) ), 2.60 (s, 3H, CH ), 7.20 (s, 1H, H-4,
3 2
3
pyrazolone), 7.40-7.58 (m, 10H, arom-H), 7.66 (s, 1H, H-5, pyri-
2-Amino-6-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-
phenylpyridine-3-carbonitrile (1).
+
dine); MS, m/z (%): 452 (19), 451 (M , 61), 410 (40), 409 (100),
391 (18), 368 (15), 367 (58).
A mixture of 4-(1-iminoethyl)-3-methyl-1-phenyl-2-pyrazolin-
5-one [7] (7.0 g, 0.03 mol) and benzylidene malononitrile (5.0 g,
0.03 mol) was heated under reflux for 3 hours in ethanol (50 mL)
and a few drops of piperidine. The solid thus precipitated was col-
lected and washed several times with ethanol and recrystallized
An Alternative Route for the Preparation of 5.
Compound 1 (0.5 g, 0.0014 mol) was refluxed with acetyl
chloride (5 mL) in pyridine (10 mL) for 3 hours. The reaction
mixture was cooled and poured into cold water, then the solid
product was separated, filtered off, and recrystallized from ben-
zene to give yellow needles of 5. It was found that the compound
from dioxane as yellow needles. The IR (KBr): υ 3400, 3300
-1
cm (NH ), 2200 (C≡N), 1620 (C=O) (the lower frequency is due
2
1
5 was identical in all aspects (mp, mixed mp, IR, H-NMR and
1
to the enol form of 5-pyrazolone) [8]. H-NMR (DMSO-d ): δ
6
MS) with that prepared from 1 with acetic anhydride.
2-Benzylamino-6-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-
yl)-4-phenylpyridine-3-carbonitrile (8a) and Ethyl 2-[3-Cyano-
6-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-phenylpyridin-
2-yl]aminoacetate (8b).
2.37 (s, 3H, CH ), 6.54 (s, 1H, H-4, pyrazolone), 7.11-7.68 (m,
3
10H, arom-H), 8.00 (s, 1H, H-5, pyridine) and 8.40 (s, 2H, NH ).
2
2-(Ethoxymethyleneamino)-6-(3-methyl-5-oxo-1-phenyl-2-pyra-
zolin-4-yl)-4-phenylpyridine-3-carbonitrile (2).
Compound 1 (1.0 g, 0.0028 mol) in excess triethyl orthofor-
mate (10 mL) was refluxed for 5 hours. The reaction mixture
was cooled and triturated with cold ethanol, the product was sep-
arated, collected by filtration, washed with petroleum ether (40-
60 °C) and recrystallized from ethanol. The IR spectrum showed
General Procedure.
A mixture of 1 (0.0014 mol) and benzyl chloride and/or ethyl
chloroacetate (5 mL) was refluxed for 2 hours, then the reaction
mixture was allowed to cool. The reaction product was triturated
with petroleum ether (40-60 °C) several times, then collected by fil-
tration, and recrystallized from the proper solvent indicated below.
Compound 8a was crystallized from benzene, IR (KBr): υ
disappearance of the bands attributable to (NH ) group, but
2
-1
1
showed bands at 2200 cm (C≡N), 1620 (C=O); H-NMR
(CDCl ): δ 1.45 (t, 3H, CH CH ), 2.60 (s, 3H, CH ), 4.55 (q, 2H,
-1
1
3
2
3
3
3370 cm (NH), 2200 (C≡N), 1650 (CO); H-NMR (CDCl ): δ
3
CH CH ), 7.26 (s, 1H, H-4, pyrazolone), 7.31-7.69 (m, 10H,
2
3
2.33 (s, 3H, CH ), 4.65 (s, 2H, CH ), 5.30 (s, 1H, NH), 7.30 (s,
3
2
arom-H), 7.72 (s, 1H, H-5, pyridine), 8.67 (s, 1H, CHOEt); MS,
1H, H-4, pyrazolone), 7.42-7.86 (m, 15H, arom-H), 8.10 (s, 1H,
H-5, pyridine); MS, m/z (%): 457 (M , 43), 456 (95), 455 (32).
+
m/z (%): 423 (M , 42), 422 (100), 408 (23), 395 (18), 394 (17),
+
367 (23), 366 (17), 348 (14), 347 (59).
Compound 8b was crystallized from ethanol, IR (KBr): υ 3350
-1
cm (NH), 2210 (C≡N), 1650 (C=O of ester group), 1620 (C=O
2-(Hydrazinomethyleneamino)-6-(3-methyl-5-oxo-1-phenyl-2-
pyrazolin-4-yl)-4-phenylpyridine-3-carbonitrile (3).
1
of pyrazolone); H-NMR (CDCl ): δ 1.60 (t, 3H, CH CH ), 2.50
3
2
3
(s, 3H, CH ), 3.00 (s, 2H, CH ), 4.20 (q, 2H, CH CH ), 5.60 (s,
3
2
2
3
To a solution of 2 (0.2 g, 0.0005 mol) in dioxane (15 mL) was
added hydrazine hydrate (5 mL), the reaction mixture was stirred
for 0.5 hours, solid product was isolated during stirring collected
1H, NH), 7.00 (s, 1H, H-4, pyrazolone), 7.30-7.69 (m, 10H,
arom-H), 7.80 (s, 1H, H-5, pyridine); MS, m/z (%): 453 (M , 43).
+
N-[3-Cyano-6-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-
phenylpyridin-2-yl]benzamide (9).
by filtration, dried, and recrystallized from methanol. The IR
-1
(KBr): υ 3450, 3300, 3200 cm (NH , NH), 2200 (C≡N), 1620
2
1
(C=O); H-NMR (CDCl ): δ 2.60 (s, 3H, CH ), 5.40 (s, 2H,
A mixture of 1 (0.5 g, 0.0014 mol) and benzoyl chloride (5 mL)
was refluxed for 2 hours, then allowed to cool and treated with
petroleum ether (60-80 °C) (50 mL), whereby petroleum ether
was decanted, the solid product was separated, collected by filtra-
tion, and washed with petroleum ether (60-80 °C) several times,
dried, and recrystallized from ethanol to give 9 as brown crystals.
3
3
NH ), 7.20 (s, 1H, NH), 7.30 (s, 1H, CH=N), 7.37 (s, 1H, H-4,
2
pyrazolone), 7.41-7.71 (m, 10H, arom-H), 7.79 (s, 1H, H-5, pyri-
+
dine); MS, m/z (%): 409 (M , 14), 395 (28), 394 (100), 393 (25),
379 (50), 366 (43).
2-(Acetylamino) and 2-(Diacetylamino)-6-(3-methyl-5-oxo-1-
phenyl-2-pyrazolin-4-yl)-4-phenylpyridine-3-carbonitrile (5,6).
-1
The IR (KBr): υ 3400 cm (NH), 2200 (C≡N), 1750 (C=O of
benzoyl), 1695 (C=O of pyrazolone). H-NMR (DMSO-d ): δ
1
6
Compound 1 (0.5 g, 0.0014 mol) was refluxed with acetic
anhydride (5 mL) for 3 hours. The reaction mixture was cooled
and then poured into cold water (100 mL), then the product was
precipitated, collected and recrystallized from benzene to give
yellow needles of 5. The filtrate was concentrated under reduced
pressure, then the solid obtained was filtered off, washed with
petroleum ether (40-60 °C) and recrystallized from benzene to
give 6 as colourless needles.
2.33 (s, 3H, CH ), 7.35 (s, 1H, H-4, pyrazolone), 7.43-7.69 (m,
3
15H, arom-H), 7.79 (s, 1H, H-5, pyridine), 8.14 (s, 1H, NH); MS,
+
m/z (%): 471 (M , 38), 470 (43), 453 (16), 452 (100).
2-Amino-6-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-
phenylpyridine-3-carboxamide (10).
Concentrated sulphuric acid (30 mL) was cooled to 20 °C and 1
(2.5 g, 0.007 mol) was added with stirring so that the temperature

Mar-Apr 2002
Synthesis and Reactions of 2-Amino-6-(3-methyl-5-oxo-1-phenyl-
2-pyrazolin-4-yl)-4-phenylpyridine-3-carbonitrile
313
did not raise above 40 °C. The addition of 1 took 0.5 hour, the solu-
tion was stirred at room temperature for 4 hours. The sulphuric acid
solution was then poured with stirring into a mixture of 500 mL of
water and ice and the solution left overnight in the refrigerator, then
the product was precipitated, collected by filtration and washed free
CH CH ), 3.20 (q, 2H, CH CH ), 6.99 (s, 1H, H-4, pyrazolone),
2 3 2 3
7.11-7.55 (m, 10H, arom-H), 8.03 (s, 1H, H-5, pyridine); MS,
+
m/z (%): 500 (14), 499 (M , 33), 498 (100).
4-Amino-7-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-5-
phenylpyrido[2,3-d]pyrimidine (15).
of excess sulphuric acid, dried, and then recrystallized from toluene.
-1
A mixture of 1 (0.5 g, 0.0014 mol) and formamide (5 mL) was
refluxed for 1 hour. On cooling, the product was precipitated,
collected by filtration, and washed several times with cold
ethanol and recrystallized from ethanol as deep violet crystals.
The IR spectrum did not exhibit any band attributable to (C≡N)
The IR (KBr): υ 3400-3300 cm (NH , CONH ), 1620 (C=O).
2
2
1
H-NMR (DMSO-d ): δ 2.33 (s, 3H, CH ), 6.40 (s, 2H, NH ), 7.06
6
3
2
(s, 1H, H-4, pyrazolone), 7.34-7.51 (m, 10H, arom-H), 7.72 (s, 1H,
H-5, pyridine), 8.05 (s, 2H, CONH ); MS, m/z (%): 386 (26), 385
2
+
(M , 100), 369 (16), 368 (64).
-1
1
but showed bands at 3400, 3300 cm (NH ), 1620 (C=O); H-
2
7-(3-Methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-5-phenylpyrido-
[2,3-d]pyrimidin-4(3H)-one (11).
NMR (DMSO-d ): δ 2.37 (s, 3H, CH ), 7.05 (s, 1H, H-4, pyra-
6
3
zolone), 7.13-7.61 (m, 10H, arom-H), 8.03 (s, 1H, H-5, pyridine),
+
Compound 10 (0.5 g, 0.0013 mol) and 15 mL of formamide
were heated at 180-190 °C for 45 minutes, then the reaction mix-
ture was cooled whereby brown precipitate formed, was collected
by filtration, dried, and recystallized from ethanol. The IR
8.40 (s, 2H, NH ); MS, m/z (%): 395 (27), 394 (M , 100), 393
2
(9), 367 (7), 261 (17).
4-Amino-2-trichloromethyl-7-(3-methyl-5-oxo-1-phenyl-2-pyra-
zolin-4-yl)-5-phenylpyrido[2,3-d]pyrimidine (16).
-1
(KBr): υ 3400 cm (NH), 1685 (CONH), 1620 (C=O of pyra-
1
zolone). H-NMR (CDCl ): δ 2.30 (s, 3H, CH ), 6.40 (s, 1H,
A mixture of 1 (1.0 g, 0.0028 mol) and trichloroacetonitrile
(0.4 mL, 0.003 mol) was refluxed in dry toluene with a catalytic
amount of piperidine for 0.5 hour. The product, which was sepa-
3
3
NH), 7.06 (s, 1H, H-4, pyrazolone), 7.32-7.50 (m, 10H, arom-H),
7.60 (s, 1H, H-5, pyridine), 7.70 (s, 1H, H-2, pyrimidine); MS,
+
m/z (%): 396 (26), 395 (M , 90), 394 (94), 377 (80), 368 (89),
rated during the reflux, was filtered off, dried and recrystallized
-1
369 (26), 343 (24), 342 (100).
from ethanol. The IR (KBr): υ 3450, 3300 cm (NH ), 1600
2
-1
1
(C=O) and no band for (C≡N) at 2200 cm 780 (C-Cl); H-NMR
(DMSO-d ): δ 2.39 (s, 3H, CH ), 5.24 (s, br, 1H, NH), 7.11 (s,
4-Phenylamino-7-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-
5-phenylpyrido[2,3-d]pyrimidine-2(1H)-thione (12).
6
3
1H, H-5, pyrazolone), 7.36-7.62 (m, 10H, arom-H), 8.00 (s, 1H,
+
Compound 1 (0.5 g, 0.0014 mol) was dissolved in pyridine (5
mL), phenyl isothiocyanate (0.2 mL, 0.0015 mol) was added to
the above solution. The reaction mixture was refluxed for 6
hours, and then cooled, whereby reddish brown crystals were
separated out, collected by filtration, dried and recrystallized
H-5, pyridine); MS, m/z (%): 511.5 (M , 40).
4-Amino-2-hydroxy-7-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-
yl)-5-phenylpyrido[2,3-d]pyrimidine (17a).
Compound 16 (0.25 g, 0.001 mol) was heated with aqueous
-1
from ethanol. The IR (KBr): υ 3400 cm (NH), 1600 (C=O),
sodium hydroxide solution (0.5 g NaOH, 5 mL H O) for 0.5
2
-1
1
1240 (C=S) and no band at 2200 cm for (C≡N); H-NMR
(DMSO-d ): δ 2.34 (s, 3H, CH ), 6.79 (s, 1H, H-4, pyrazolone),
hour, then the product was obtained, collected by filtration, and
recrystallized from aqueous ethanol. The IR (KBr): υ br. band at
6
3
-1
7.10-7.79 (m, 15H, arom-H), 8.04 (s, 1H, H-5, pyridine), 8.55 (s,
1H, NH), 9.81 (s, 1H, SH).
3000-3300 (OH, NH ), 1600 cm (C=O) and no band at 780 for
2
1
C-Cl; H-NMR (CDCl ): 2.38 (s, 3H, CH ), 5.35 (s, 2H, NH ),
3
3
2
6.90 (s, 1H, H-4, pyrazolone), 7.13-7.42 (m, 10H, arom-H), 7.50
(s, 1H, H-5, pyridine), 8.50 (s, 1H, OH); MS, m/z (%): 410 (M ,
15).
7-(3-Methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-5-phenylpyrido-
[2,3-d]pyrimidine-2,4(1H,3H)-dithione (13).
+
Compound 1 (1.0 g, 0.0028 mol) was dissolved in 10% alco-
holic sodium hydroxide solution (5 mL), and then refluxed with
excess carbon disulphide on a water bath for 8 hours. During the
reflux time fresh carbon disulphide was added (two times), then
the product was separated, collected by filtration, and recrystal-
lized from acetic acid as deep red crystals. The IR (KBr): υ 3400,
4-Amino-2-ethoxy-7-(3-mehtyl-5-oxo-1-phenyl-2-pyrazolin-4-
yl)-5-phenylpyrido[2,3-d]pyrimidine (17b).
A mixture of 16 (0.25 g, 0.001 mol) and sodium ethoxide solu-
tion (0.1 g Na/10 mL absoulte ethanol) was refluxed for 0.5 hour.
After cooling, the precipitated solid was collected by filtration
and recrystallized from dioxane. The IR (KBr): υ 3460, 3360
-1
-1
3280 cm (2 NH), 1600 (C=O), and no band at 2220 cm for
1
-1
1
(C≡N); H-NMR (DMSO-d ): δ 2.3 (s, 3H, CH ), 6.99 (s, 1H,
cm (NH ), 1680 (C=O); H-NMR (DMSO-d ): δ 1.50-1.70 (t,
6
3
2
6
H-4, pyrazolone), 7.11-7.49 (m, 10H, arom-H), 7.55 (s, 1H, H-5,
pyridine), 8.04 (s, 2H, 2 NH); MS, m/z (%): 443 (M , 24).
3H, CH CH ), 2.35 (s, 3H, CH ), 3.45 (q, 2H, CH CH ), 6.95 (s,
2
3
3
2
3
+
2H, NH ), 7.20 (s, 1H, H-4, pyrazolone), 7.35-7.69 (m, 10H,
2
+
arom-H), 7.80 (s, 1H, H-5, pyridine); MS, m/z (%): 438 (M , 16).
2,4-Bis(ethylmercapto)-7-(3-methyl-5-oxo-1-phenyl-2-pyra-
zolin-4-yl)-5-phenylpyrido[2,3-d]pyrimidine (14).
4-Chloro-7-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-5-
phenylpyrido[2,3-d][1,2,3]triazine (18).
Compound 13 (0.5 g, 0.0011 mol) was refluxed with ethyl
iodide (2 mL, 0.018 mol) in ethanol (20 mL) in the presence of
anhydrous sodium acetate (2.0 g) for 2 hours. The colour of the
reaction mixture changed from red to brown, then the brown
product was precipitated, collected by filtration, and recrystal-
To a cold solution of 1 (0.5 g, 0.0014 mol) in hydrochloric acid
(2 mL) added a solution of sodium nitrite (0.15 g, 0.002 mol) in 5
mL of water with stirring in ice-bath (at 5 °C), after the complete
addition of sodium nitrite solution the product was separated, col-
lected by filtration, and recrystallized from ethanol to give 18.
lized from dioxane as deep brown crystals. The IR (KBr): υ 1650
-1
1
The IR (KBr): υ 1620 cm (C=O) and disappearance of the band
(C=O), no bands for NH, H-NMR (CDC1 ): δ 1.15 (t, 3H,
3
1
attributed to (C≡N); H-NMR (CDC1 ): δ 2.30 (s, 3H, CH ),
CH CH ), 1.42 (t, 3H, CH CH ), 2.43 (s, 3H, CH ), 2.97 (q, 2H,
3
3
2
3
2
3
3

314
R. A. Ahmed, M. M. Kandeel, M. S. Abbady and M. S. K. Youssef
Vol. 39
[3] M. M. Kandeel, M. S. Abbady and M. S. K. Youssef, Bull.
Soc. Chim. France, 1005 (1986).
7.30 (s, 1H, H-5, pyrazolone), 7.42-7.79 (m, 10H, arom-H), 8.10
(s, 1H, H-5, pyridine); MS, m/z (%): 414 (M , 30).
+
[4] A. M. Osman, M. S. K. Youssef and Kh. M. Hassan, J.
Prakt. Chem., 320, 857 (1978).
[5] S. Devi, P. Mitra, S. B. Mishra and A. S. Mittra, J. Indian
Chem. Soc., 60, 679 (1983).
[6] S. Rao and A. S. Mittra, J. Indian Chem. Soc., 55, 745
(1978).
[7] S. Rao and A. S. Mittra, Indian. J. Chem., 15B, 1062
(1977).
REFERENCES AND NOTES
nd
[1] Presented at the 2 International Conference on Basic
Sciences And Advanced Technology, Assiut Univ., Fac. Sci, Assiut,
Egypt, 2000, Nov. 5-8, Abstr. (III-B) P2, p. 313.
th
[2] M. M. Kandeel, M. S. Abbady and M. S. K. Youssef, 7
Ibn Sina International Conference On Pure And Applied Chemistry,
Alexandria Univ., Fac. Sci, Alexandria, Egypt, 2000, March. 25-28,
Abstr. P. 194; Bull. Korean Chem. Soc., 23 (1), 41 (2002)
[8] A. R. Katritzky and A. J. Boulton, Advances in
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London. 1976, p. 314.