Synthesis of 2-R-3-Hydroxy[1,2,4]triazino[6,1-b]-quinazoline-4,10-diones

Article abstract of DOI:10.1134/S1070428006050186

A preparation method was developed for [1,2,4]triazino[6,1-b]quinazoline-4, 10-diones using isatoic anhydride, carboxylic acids hydrazides, ethyl oxalyl chloride, and hydroxylamine. Pleiades Publishing, Inc. 2006.

Full text of DOI:10.1134/S1070428006050186

ISSN 1070-4280 Russian Journal of Organic Chemistry, 2006, Vol. 42, No. 5, pp. 752-756. Ó Pleiades Publishing, Inc. 2006.
Original Russian Text Ó L.A. Shemchuk, V.P. Chernykh, O.S. Krys’kiv, 2006, published in Zhurnal Organicheskoi Khimii, 2006, Vol. 42, No. 5,
pp. 768-771.
Synthesis
of 2-R-3-Hydroxy[1,2,4]triazino[6,1-b]-quinazoline-4,10-diones
L.A. Shemchuk, V.P. Chernykh, and O.S. Krys’kiv
Ukrainian Pharmaceutical University, Kharkiv, 61002 Ukraine
Received January 17, 2005
Abstract—A preparation method was developed for [1,2,4]triazino[6,1-b]quinazoline-4,10-diones using isatoic
anhydride, carboxylic acids hydrazides, ethyl oxalyl chloride, and hydroxylamine.
DOI: 10.1134/S1070428006050186
Application of anthranilic and dicarboxylic acids
derivatives for building up a quinazolinone ring furnishes
structures that open wide opportunities for constructing
thereon new heterocyclic systems, in particular, those with
fused heterocyclic rings [1].
carried out at 0°C afforded ester IIIb, and without cooling
the reaction mixture self-heated and alongside the
acylation occurred also cyclodehydration furnishing 3-
acylamino-2-ethoxycarbonylquinazolin-4-ones IVa–IVf.
A short (4–6 min) heating of ester IIIb also results in
formation of quinazolinone IVb. In the 1H NMR spectrum
of ester IVb lack the signals from two NH groups existing
in the 1H NMR spectrum of ester IIIb.
The simplest methods suggested nowadays for the
synthesis of compounds from the triazinoquinazolinone
series are based mainly on the application as an initial
substance of ethyl 3-amino-4-oxo-3,4-dihydroquinazoline-
2-carboxylate [2] which is commonly obtained by reaction
of the anthranilohydrazide with the diethyl oxalate [3].
Considering that the yields of acylhydrazides are
virtually quantitative and that the hydrazinolysis and
acylation can be performed under similar conditions
(DMF in the presence of triethylamine) we have decided
to prepare esters IIIb, IVa–IVf omitting the isolation of
intermediate products IIa–IIf. This reduced the
experimental time due to decreasing the number of stages
involving separation and purification of the reaction
products, and also improved the yields of esters IIIb,
IVa–IVf calculated on the initial anhydride.
We report here on the synthesis of 2-R-3-hydroxy-
[1,2,4]triazino[6,1-b]quinazoline-4,10-diones VIIa–VIIf,
a new group of substances with a potential biologic action
(see the scheme). First the presumed initial synthons for
their preparation were 3,1-benzoxazin-4-ones derivatives,
isatoic anhydride (I) or 3,1-benzoxazin-4-on-2-carboxylic
acid N-hydroxyamide (VIII).
The reaction of esters IIIb, IVa–IVf with hydroxyl-
amine furnished in good yields the corresponding
hydroxamic acids Vb, VIa–VIf which readily underwent
cyclization at heating in acetic anhydride. In both cases
the reaction products were diones VIIa–VIIf. In reaction
of hydroxamic acid Vb quinazoline and triazine rings
close simultaneously. We failed to stop the reaction at
the stage of the quinazoline ring closure (we did not
succeed in hydroxyamide VIb isolation). The ease of
the closure of both rings apparently is due to the enhanced
nucleophilic properties of the hydrazide and N-hydroxy-
amide groups (a-effect) [5].
From the two assumed synthetic procedures the one
involving isatoic anhydride (I) proved to be more success-
ful. Its reaction with carboxylic hydrazides provided
2-N-acylanthranilohydrazides IIa–IIf. The hydrazinolysis
was carried out in DMF; the reaction occurred cleaner in
the presence of triethylamine.Asimilar condensation with
arylcarboxylic hydrazides in the presence of the p-toluene-
sulfonic acid was formerly applied to the one-stage
preparation of 2-aryl-3-aminoquinazolin-4-ones [4].
Acylhydrazides IIa–IIf obtained were treated with
ethyl oxalyl chloride in DMF or acetic acid in the presence
of triethylamine. Different products were isolated
depending on the reaction temperature. The reaction
In keeping with the second scheme we planned to
synthesize the triazinoquinazoline system proceeding from
752

SYNTHESIS OF 2-R-3-HYDROXY[1,2,4]TRIAZINO[6,1-b]-QUINAZOLINE -4,10-DIONES
753
Scheme.
2
2
2
2
1+1+
5
2
1+
5
1+
1
+
2
1+
B
,
,, ꢀꢀꢀ,,I
2
2
2
2
1+ 2+
5
5
1+
1+
1+
1+
2
1
1+&2&22(W
,,,E
1+&2&21+2+
&2&O
1
2
5
9E
&22(W
1
1
2
2
2
2
2
+
5
5
1+ 2+
1
1
1+
1+
B
9,, ꢀꢀꢀ9,,I
1
&22(W
1
&21+2+
B
B
,9 ꢀꢀ,9I
9, ꢀꢀꢀ9,I
2
2+
1
5ꢀ ꢀ0Hꢀꢁ ꢂꢃꢀ3KꢀꢁEꢂꢃꢀꢄꢅ+2& + ꢀꢁFꢂꢃꢀS\ULG\OꢀꢁGꢂꢃꢀꢄIXU\OꢀꢁHꢂꢃ
ꢁIꢂꢆ
1
N-hydroxyamide VIII; however this route turned out to
be less favorable because of complications in the
preparation of compound VIII by cyclization of 2-carboxy-
oxanilic acid N-hydroxyamide in acetic anhydride by
method [6]. The target products were obtained in a low
yield with impurity of acetylation products.
2-N-Acetylanthranilohydrazide (IIa). Yield 80%,
mp 235–237°C. 1H NMR spectrum, d, ppm: 2.55 s (3H,
CH3), 6.30 br.s (2H, NH2), 7.16 t (1Harom), 7.28 t
(1Harom), 7.42 d (1Harom), 7.76 d (1Harom), 10.60 br.s (2H,
NHNH). Found, %: C 56.23; H 5.57; N 21.69.
C9H11N3O2. Calculated, %: C 55.95; H 5.74; N 21.75.
2-N-(2-Hydroxybenzoyl)anthranilohydrazide
(IIc). Yield 95%, mp 208–210°C. 1H NMR spectrum, d,
ppm: 6.40 br.s (2H, NH2), 6.50–7.80 m (8Harom),
10.30 br.s (2H, NHNH), 11.05 br.s (1H, OH). Found, %:
C 62.40; H 5.01; N 15.52. C14H13N3O3. Calculated, %:
C 61.99; N 15.49; H 4.83.
EXPERIMENTAL
1H NMR spectra were registered on a spectrometer
Varian M200, operating frequency 200 MHz, from
solutions in DMSO-d6 with TMS as internal reference.
Elemental analyses were performed on an analyzer Carlo
Erba CHNS-O EA 1108.
2-N-(4-Isonicotinoyl)anthranilohydrazide (IId).
1
Yield 71%, mp 195–197°C. H NMR spectrum, d, ppm:
2-N-Benzoylanthranilohydrazide (IIb). In 3 ml of
DMF was dissolved 0.01 mol (1.63 g) of isatoic anhydride
(²), thereto was added 0.01 mol (1.4 ml) of triethylamine
and a solution of 0.01 mol (1.36 g) of benzoic hydrazide
in 3 ml of DMF. After 4 h the mixture was diluted with
cold water. Yield 2.51 g, mp 210–212°C (from AcOH).
1H NMR spectrum, d, ppm: 6.45 br.s (2H, NH2), 6.55–
7.65 m (9Harom), 10.45 br.s (2H, NHNH). Found, %:
C 65.62; H 4.95; N 16.51. C14H13N3O2. Calculated, %:
C 65.87; H 5.13; N 16.46.
6.30 br.s (2H, NH2), 6.25–7.55 m (8Harom), 10.30 br.s
(2H, NHNH). Found, %: C 60.65; H 4.84; N 21.91.
C13H12N4O2. Calculated, %: C 60.93; H 4.72; N 21.86.
2-N-(2-Furoyl)anthranilohydrazide (IIe). Yield
1
78%, mp 285–287°C. H NMR spectrum, d, ppm:
6.45 br.s (2H, NH2), 6.65–8.10 m (7Harom), 10.40 br.s
(2H, NHNH). Found, %: C 59.07; H 4.43; N 17.05.
C12H11N3O3. Calculated, %: C 58.77; H 4.52; N 17.13.
3-Hydroxy-4-oxo-3,4-dihydroquinazoline-2-carb-
oxylic 2-N-(2-aminobenzoyl)hydrazide (IIf). Yield
67%, mp 186–188°C. 1HNMRspectrum, d, ppm: 6.50 br.s
Hydrazides IIa, IIc–IIf were obtained in the same
way.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 42 No. 5 2006

SHEMCHUK et al.
754
(2H, NH2), 7.45–8.60 m (8Harom), 10.35 br.s (2H,
NHNH), 12.20 br.s (1H, OH). Found, %: C 56.51;
H 3.98; N 20.59. C16H13N5O4. Calculated, %: C 56.64;
H 3.98; N 20.64.
Ethyl 3-(acetylamino)-4-oxo-3,4-dihydroquinazo-
line-2-carboxylate (²Va).Yield 65%, mp 141–143°C. 1H,
d, ppm: 1.05 t (3H, CH2CH3), 4.05 m (2H, CH2CH3),
2.55 s (3H, COCH3), 7.00 t (1Harom), 7.30 d (1Harom),
7.55 t (1Harom), 7.80 d (1Harom), 11.50 br.s (1H, NH).
Found, %: C 57.01; H 4.63; N 15.20. C13H13N3O4.
Calculated, %: C 56.73; H 4.76; N 15.27.
Benzoic 2-N-[2-(ethoxalylamino)benzoyl]-
hydrazide (²IIb). a. In 3 ml of the glacial acetic acid (or
DMF) was dissolved 0.01 mol (2.55 g) of acylhydrazide
²²b, 0.01 mol (1.4 ml) of triethylamine was added, the
mixture was cooled to 0°C, and 0.01 mol (1.2 ml) of ethyl
oxalyl chloride was added.After 3 h the reaction mixture
was diluted with cold water. Yield 3.42 g, mp 101–103°C
(from acetic acid).
Ethyl 3-(2-hydroxybenzoylamino)-4-oxo-3,4-di-
hydroquinazoline-2-carboxylate (²Vc). Yield 93%, mp
1
132–134°C. H NMR spectrum, d, ppm: 1.15 t (3H,
CH2CH3), 4.05 m (2H, CH2CH3), 6.40–7.55 m (8Harom),
11.55 br.s (1H, NH), 11.20 br.s (1H, OH). Found, %:
C 61.26; H 4.20; N 11.97. C18H15N3O5. Calculated, %:
C 61.19; H 4.28; N 11.89.
b. In 3 ml of DMF was dissolved 0.01 mol (1.63 g) of
isatoic anhydride (²), thereto was added 0.01 mol
(1.4 ml) of triethylamine and a solution of 0.01 mol
(1.36 g) of benzoic hydrazide in 3 ml of DMF. After 4 h
the mixture was cooled to 0°C, and 0.01 mol (1.2 ml) of
ethyl oxalyl chloride was added. After 3 h the reaction
mixture was diluted with cold water. Yield 3.46 g, mp
Ethyl 3-(2-isonicotinoylamino)-4-oxo-3,4-dihydro-
quinazoline-2-carboxylate (²Vd). Yield 82%, mp 128–
130°C. 1H NMR spectrum, d, ppm: 1.10 t (3H, CH2CH3),
4.10 m (2H, CH2CH3), 6.35–7.80 m (8Harom), 11.70 br.s
(1H, NH). Found, %: C 60.48; H 4.26; N 16.48.
C17H14N4O4. Calculated, %: C 60.35; H 4.17; N 16.56.
1
102–104°C (from AcOH). H NMR spectrum, d, ppm:
Ethyl 3-(2-furoylamino)-4-oxo-3,4-dihydroquinazo-
line-2-carboxylate (²Ve). Yield 89%, mp 220–222°C.
1H NMR spectrum, d, ppm: 1.10 t (3H, CH2CH3), 4.15 m
(2H, CH2CH3), 6.80–8.10 m (7Harom), 11.90 br.s (1H,
NH). Found, %: C 58.92; H 4.00; N 12.84.
1.15 t (3H, CH2CH3), 4.10 m (2H, CH2CH3), 6.80–
7.95 m (9Harom), 9.50 br.s (1H, NH), 10.95 br.s (2H,
NHNH). Found, %: C 61.19; H 5.02; N 11.89.
C18H17N3O5. Calculated, %: C 60.84; H 4.82; N 11.82.
Ethyl 3-(benzoylamino)-4-oxo-3,4-dihydroquinazo-
line-2-carboxylate (²Vb). a. In 3 ml of the glacial acetic
acid (or DMF) was dissolved 0.01 mol (2.55 g) of
acylhydrazide ²²b, 0.01 mol (1.4 ml) of triethylamine and
0.01 mol (1.2 ml) of ethyl oxalyl chloride was added.
After 3 h the reaction mixture was diluted with cold
water. Yield 3.29 g, mp 118–120°C (from ethanol).
Ethyl 3-(3-hydroxy-4-oxo-3,4-dihydro-quinazolin-2-
ylcarbonylylamino)-4-oxo-3,4-dihydroquinazoline-2-
carboxylate (²Vf). Yield 87%, mp 118–120°C. 1H NMR
spectrum, d, ppm: 1.10 t (3H, CH2CH3), 4.05 m (2H,
CH2CH3), 7.35–8.60 m (8Harom), 11.00 br.s (1H, NH),
12.35 br.s (1H, OH). Found, %: C 56.84; H 3.72; N 16.70.
C20H15N5O6. Calculated, %: C 57.01; H 3.59; N 16.62.
b. In 3 ml of the glacial acetic acid 0.01 mol (3.55 g)
of ester ²²²b was boiled for 5 min and on cooling was
diluted with cold water.Yield 3.33 g, mp 118–120°C (from
ethanol).
Preparation of the methanol solution of hydroxyl-
amine. In a minimal volume of methanol was dissolved
0.012 mol (0.28 g ) of sodium, and at cooling a solution of
0.012 mol (0.84 g) hydroxylamine hydrochloride was
added. After 15 min the precipitate was removed, and
the filtrate was used in further reactions.
c. In 3 ml of DMF was dissolved 0.01 mol (1.63 g) of
isatoic anhydride (²), thereto was added 0.01 mol
(1.4 ml) of triethylamine and a solution of 0.01 mol
(1.36 g) of benzoic hydrazide in 3 ml of DMF. In 4 h
0.01 mol (1.2 ml) of ethoxalyl chloride was added. After
keeping the mixture for 3 h it was diluted with cold water.
Benzoic
N'-[2-(ethoxalylamino)benzoyl]-
hydrazide N-hydroxyamide (Vb). In 5 ml of methanol
was dissolved 0.01 mol (3.55 g) of ester ²²²b, and
0.012 mol of hydroxylamine in methanol solution was
added. The mixture was stirred for 30 min at 50°C. After
6 h the precipitate formed was separated. Yield 3.27 g,
mp 183–185°C (fromAcOH). 1H NMR spectrum, d, ppm:
6.95–8.20 m (9Harom), 9.50 br.s (1H, NH), 10.90 m (2H,
NHNH), 11.85 br.s (1H, NHOH), 12.15 br.s (1H,
NHOH). Found, %: C 55.78; H 4.22; N 16.40.
C16H14N4O5. Calculated, %: C 56.14; H 4.12; N 16.37.
1
Yield 3.35 g, mp 117–119°C (from AcOH). H NMR
spectrum, d, ppm: 1.10 t (3H, CH2CH3), 4.00 m (2H,
CH2CH3), 6.95–7.80 m (9Harom), 12.05 br.s (1H, NH).
Found, %: C 63.88; H 4.32; N 12.52. C18H15N3O4.
Calculated, %: C 64.09; H 4.48; N 12.46.
Esters IVa, IVc–IVf were obtained by similar
procedures.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 42 No. 5 2006

SYNTHESIS OF 2-R-3-HYDROXY[1,2,4]TRIAZINO[6,1-b]-QUINAZOLINE -4,10-DIONES
755
3-(Benzoylamino)-4-oxo-3,4-dihydroquinazoline-2-
carboxylic acid N-hydroxyamide (V²b). In 5 ml of
methanol was dissolved 0.01 mol (3.37 g) of ester ²Vb,
and 0.012 mol of hydroxylamine in methanol solution was
added. The mixture was stirred for 30 min at 50°C. After
6 h the precipitate formed was separated. Yield 3.19 g,
mp 205–207°C (from acetic acid). 1H NMR spectrum, d,
ppm: 6.95–8.05 m (9Harom), 10.15 br.s (1H, NNH),
10.40 br.s (1H, NHOH), 11.50 br.s (1H, NHOH). Found,
%: C 59.41; H 3.52; N 17.20. C16H12N4O4. Calculated,
%: C 59.26; H 3.69; N 17.28.
%: C 53.16; H 3.08; N 20.51. C18H12N6O6. Calculated,
%: C 52.95; H 2.96; N 20.58.
3-Hydroxy-2-phenyl[1,2,4]triazino[6,1-b]quinazo-
line-4,10-dione (V²Ib). a. In 5 ml of acetic anhydride
0.01 mol (3.42 g) of N-hydroxyamide Vb was heated for
15 min. On cooling the mixture was diluted with cold
water. Yield 2.97 g, mp 272–274°C (from AcOH).
1H NMR spectrum, d, ppm: 7.0–8.40 m (9Harom),
11.45 br.s (1H, OH). Found, %: C 62.43; H 3.16; N 18.34.
C16H10N4O3. Calculated, %: C 62.75; H 3.29; N 18.29.
b. In 5 ml of acetic anhydride 0.01 mol (3.24 g) of
N-hydroxyamide V²b was heated for 5 min. On cooling
N-Hydroxyamides V²a, VIc–VIf were obtained by the
same procedure.
the mixture was diluted with cold water. Yield 3.01 g
mp 273–275°C (from AcOH).
,
3-(Acetylamino)-4-oxo-3,4-dihydroquinazoline-2-
carboxylic acid N-hydroxyamide (V²a). Yield 96%, mp
210–212°C. HNMR spectrum, d, ppm: 2.60 s (3H, CH3),
6.85 t (1Harom), 7.05 d (1Harom), 7.25 t (1Harom), 7.60 d
(1Harom), 10.35 br.s (1H, NNH), 11.00 br.s (1H, NHOH),
11.95 br.s (1H, NHOH). Found, %: C 50.27; H 3.99;
N 21.31. C11H10N4O4. Calculated, %: C 50.38; H 3.84;
N 21.37.
Compounds V²²a, VIIc–VIIf were prepared similarly.
1
3-Hydroxy-2-methyl[1,2,4]triazino[6,1-b]-quin-
azoline-4,10-dione (V²²a). Yield 92%, mp 268–270°C.
1H NMR spectrum, d, ppm: 2.50 s (3H, CH3), 6.85 t
(1Harom), 7.05 d (1Harom), 7.25 t (1Harom), 7.60 d (1Harom),
11.25 br.s (1H, OH). Found, %: C 53.78; H 3.14; N 22.96.
C11H18N4O3. Calculated, %: C 54.10; H 3.30; N 22.94.
3-(2-Hydroxybenzoylamino)-4-oxo-3,4-dihydro-
quinazoline-2-carboxylic acid N-hydroxyamide (V²c).
Yield 92%, mp 192–194°C. 1H NMR spectrum, d, ppm:
6.65–7.80 m (8Harom), 10.20 br.s (1H, NNH), 10.80 br.s
(1H, NHOH), 11.05 br.s (1H, OH), 11.45 br.s (1H,
NHOH). Found, %: C 56.57; H 3.42; N 16.51.
C16H12N4O5. Calculated, %: C 56.47; H 3.55; N 16.46.
3-Hydroxy-2-(2-hydroxyphenyl)[1,2,4]triazino-
[6,1-b]quinazoline-4,10-dione (V²²c). Yield 94%, mp
1
256–258°C. H NMR spectrum, d, ppm: 7.00–8.10 m
(8Harom), 10.85 br.s (1H, OH), 11.15 br.s (1H, NOH).
Found, %: C 59.90; H 3.21; N 17.31. C16H10N4O4.
Calculated, %: C 59.63; H 3.13; N 17.38.
3-Hydroxy-2-(4-pyridyl)[1,2,4]triazino[6,1-b]-
quinazoline-4,10-dione (V²²d). Yield 85%, mp 273–
3-(Isonicotinoylamino)-4-oxo-3,4-dihydroquinazo-
line-2-carboxylic acid N-hydroxyamide (V²d). Yield
81%, mp 208–210°C. 1H NMR spectrum, d, ppm: 6.55–
8.25 m (8Harom), 10.30 br.s (1H, NNH), 10.50 br.s (1H,
NHOH), 11.65 br.s (1H, NHOH). Found, %: C 54.93;
H 3.32; N 21.47. C15H11N5O4. Calculated, %: C 55.39;
H 3.41; N 21.53.
1
275°C. H NMR spectrum, d, ppm: 6.70–8.05 m (8Harom),
11.40 br.s (1H, OH). Found, %: C 58.44; H 2.69; N 22.77.
C15H9N5O3. Calculated, %: C 58.63; H 2.95; N 22.79.
3-Hydroxy-2-(2-furyl)[1,2,4]triazino[6,1-b]-quin-
azoline-4,10-dione (V²²e). Yield 91%, mp > 290°C.
1H NMR spectrum, d, ppm: 7.05–8.30 m (7Harom),
11.30 br.s (1H, OH). Found, %: C 56.84; H 2.79; N 18.92.
C14H8N4O4. Calculated, %: C 56.79; H 2.72; N 18.91.
3-(2-Furoylamino)-4-oxo-3,4-dihydroquinazoline-2-
carboxylic acid N-hydroxyamide (V²e). Yield 91%, mp
1
3-Hydroxy-2-(3-hydroxyquinazolin-4-on-2-yl)-
[1,2,4]triazino[6,1-b]quinazoline-4,10-dione (V²²f).
Yield 89%, mp 240–242°C. 1H NMR spectrum, d, ppm:
7.35–8.15 m (8Harom), 12.35 br.s (2H, 2OH). Found, %:
C 55.59; H 2.47; N 21.50. C18H10N6O5. Calculated, %:
C 55.39; H 2.58; N 21.53.
264–266°C. H NMR spectrum, d, ppm: 6.90–8.20 m
(7Harom), 10.35 br.s (1H, NNH), 11.55 br.s (1H, NHOH),
11.55 br.s (1H, NHOH). Found, %: C 53.07; H 3.14;
N 17.89. C14H9N4O5. Calculated, %: C 53.51; H 3.21;
N 17.83.
3-(3-Hydroxy-4-oxo-3,4-dihydroquinazoline-2-
carbonylamino)-4-oxo-3,4-dihydroquinazoline-2-
carboxylic acid N-hydroxyamide (V²f). Yield 93%, mp
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1
188–190°C. H NMR spectrum, d, ppm: 7.20–8.00 m
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(8Harom), 10.75 br.s (1H, NNH), 11.20 br.s (1H, NHOH),
12.05 br.s (1H, NOH), 12.30 br.s (1H, NHOH). Found,
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 42 No. 5 2006

SHEMCHUK et al.
756
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