Five-membered 2,3-dioxo heterocycles: LXXVI. Reaction of methyl 1-aryl-3-benzoyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates with 6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione

Article abstract of DOI:10.1134/S1070428011060170

Methyl 1-aryl-3-benzoyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates reacted with 6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione to give methyl 11-aryl-12-benzoyl-9-hydroxy-4,6-dimethyl-3,5,10-trioxo-4,6,8, 11-tetraazatricyclo[7.2.1.0^2,7]dodec-2(7)-ene-1-carboxylates which underwent thermal recyclization to 1-aryl-3-benzoyl-4-hydroxy-1′,3′- dimethylspiro[pyrrole-2,5′-pyrrolo[2,3-d]pyrimidine]-2′,4′,5, 6′(1H,1′H,3′H,7′H)-tetraones. Pleiades Publishing, Ltd., 2011.

Full text of DOI:10.1134/S1070428011060170

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2011, Vol. 47, No. 6, pp. 933–936. © Pleiades Publishing, Ltd., 2011.
Original Russian Text © E.S. Denislamova, N.V. Bubnov, A.N. Maslivets, 2011, published in Zhurnal Organicheskoi Khimii, 2011, Vol. 47, No. 6,
pp. 915–918.
Five-Membered 2,3-Dioxo Heterocycles:
LXXVI.* Reaction of Methyl 1-Aryl-3-benzoyl-4,5-dioxo-
4,5-dihydro-1H-pyrrole-2-carboxylates with 6-Amino-
1,3-dimethylpyrimidine-2,4(1H,3H)-dione
E. S. Denislamovaa, N. V. Bubnovb, and A. N. Maslivetsa, b
a Perm State University, ul. Bukireva 15, Perm, 614990 Russia
e-mail: koh2@psu.ru
b Institute of Natural Sciences, Perm State University, Perm, Russia
Received July 7, 2010
Abstract—Methyl 1-aryl-3-benzoyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates reacted with 6-amino-
1,3-dimethylpyrimidine-2,4(1H,3H)-dione to give methyl 11-aryl-12-benzoyl-9-hydroxy-4,6-dimethyl-3,5,10-
trioxo-4,6,8,11-tetraazatricyclo[7.2.1.02,7]dodec-2(7)-ene-1-carboxylates which underwent thermal recycliza-
tion to 1-aryl-3-benzoyl-4-hydroxy-1′,3′-dimethylspiro[pyrrole-2,5′-pyrrolo[2,3-d]pyrimidine]-
2′,4′,5,6′(1H,1′H,3′H,7′H)-tetraones.
DOI: 10.1134/S1070428011060170
Monocyclic 1H-pyrrole-2,3-diones are known to
react with difunctional nucleophiles to produce various
five-, six-, and seven-membered nitrogen-containing
heterocycles, as well as fused and spirocyclic systems
[2, 3]. We previously showed that methyl 1-aryl-3-
aroyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carbox-
ylates react with 3-amino-5,5-dimethylcyclohex-2-en-
1-one (as 1,3-C,N-binucleophile) via successive addi-
tion of the β-CH group and amino group in the
enamino fragment of the binucleophile at the carbon
atoms in positions 2 and 4 of dioxopyrrole with forma-
tion of diazatricyclo[7.2.1.02,7]dodec-2(7)-ene deriva-
tives. The latter undergo recyclization on heating to
give spiro[indole-3,2′-pyrroles] together with spiro-
[furan-2,3′-indoles] as by-products [4, 5]. Reactions of
methyl 1-aryl-3-aroyl-4,5-dioxo-4,5-dihydro-1H-pyr-
role-2-carboxylates with heterocyclic enamines were
not studied.
The reactions were carried out by heating equimolar
amounts of pyrroledione Ia–Ie and enamine II in
boiling anhydrous 1,2-dichloroethane over a period of
4–6 h (until bright red color intrinsic to initial com-
pounds I disappeared). As a result, we isolated the
corresponding methyl 11-aryl-12-benzoyl-9-hydroxy-
4,6-dimethyl-3,5,10-trioxo-4,6,8,11-tetraazatricyclo-
[7.2.1.02,7]dodec-2(7)-ene-1-carboxylates IIIa–IIIe
(Scheme 1) [6]. Compounds IIIa–IIIe are colorless or
light yellow high-melting crystalline substances which
are readily soluble in dimethyl sulfoxide and dimethyl-
formamide, poorly soluble in other common organic
solvents, and insoluble in water and saturated hydro-
carbons. They showed negative color test for enolic
hydroxy group with an alcoholic solution of iron(III)
chloride.
The IR spectra of IIIa–IIIe contained absorption
bands due to stretching vibrations of the NH group
(3316–3340 cm–1), OH group (a broad band at 3145–
3165 cm–1), lactam carbonyl groups in the pyrimidine
fragment (C3=O, C5=O, 1738–1770 cm–1), ester car-
bonyl group (1721–1735 cm–1), lactam carbonyl group
in the diazepine fragment (C10=O, 1702–1710 cm–1),
and benzoyl carbonyl group (1620–1643 cm–1). Com-
In continuation of studies in this line, in the present
work we examined reactions of methyl 1-aryl-3-ben-
zoyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates
Ia–Ie with 6-amino-1,3-dimethylpyrimidine-
2,4(1H,3H)-dione (II) which may be regarded as po-
tential 1,3-C,N-binucleophile (heterocyclic enamine).
1
pounds IIIa–IIIe displayed in the H NMR spectra
* For communication LXXV, see [1].
933

DENISLAMOVA et al.
934
Scheme 1.
Me
O
COOMe
Ar
O
O
H2N
N
O
1
11
MeO
N
O
Ph
Me
O
Me
O
N
COPh
O
O
3
N
N4
5
2
7
Ar
N
H
12
+
Me
O
10
6
N
9
8
O
H2N
N
O
N
N
O
H
OH
O
MeO
Me
Me
Ar
Ph
OH
Ia–Ie
II
A
IIIa–IIIe
Me
N
Me
H
H2N
O
N
O
N
1'
7'
MeO
N
2'
6'
O
O
Ar
Δ
Δ
5'
Ar
N
3'N
4'
N1
5
Me
Me
2
–MeOH
3
O
O
O
O
4
COPh
O
OH
IVa–IVe
Ph
OH
A
Ar = Ph (a), 4-MeC6H4 (b), 4-ClC6H4 (c), 4-MeOC6H4 (d), 4-BrC6H4 (e).
signals from protons in the aromatic rings and substit-
uents attached thereto, two singlets from methyl
protons (δ 3.07–3.16 ppm), a singlet from the ester
methoxy group (δ 3.36–3.38 ppm), a singlet from 12-H
(δ 4.80–4.85 ppm), a singlet from the hydroxy proton
(δ 7.80–7.96 ppm), and a singlet from the NH proton
(δ 8.48–8.56 ppm). The 13C NMR spectrum of IIIa
contained the following signals, δC, ppm: 27.73 and
30.14 (Me), 51.37 (C12), 54.70 (C1), 65.50 (MeO),
85.64 (C9); 125.43, 127.97, 128.87, 133.86, 137.33
(Carom); 150.80 (C5), 157.85 (C2), 166.08 (C=O, ester),
167.05 (C10), 196.15 (PhCO). The spectral parameters
of IIIa–IIIe are fairly similar to those of model 13-al-
lyl-20-(4-bromobenzoyl)-12-hydroxy-16,16-dimethyl-
3 - p h e n y l - 3 , 1 0 , 1 3 - t r i a z a p e n t a c y c l o -
[10.7.1.01,10.04,9.014,19]eicosa-4,6,8,14(19)-tetraene-
2,11,18-trione whose structure was proved by X-ray
analysis [7].
lower nucleophilicity of aminouracil II as compared to
dimedone imine.
By heating tricyclic compounds IIIa–IIIe in boil-
ing m-xylene over a period of 14–16 h (TLC) we ob-
tained 1-aryl-3-benzoyl-4-hydroxy-1′,3′-dimethyl-
spiro[pyrrole-2,5′-pyrrolo[2,3-d]pyrimidine]-
2′,4′,5,6′(1H,1′H,3′H,7′H)-tetraones IVa–IVe
(Scheme 1). Compounds IVa–IVe were isolated as
yellow high-melting crystalline substances which were
readily soluble in dimethyl sulfoxide and dimethyl-
formamide, poorly soluble in other common organic
solvents, and insoluble in water and saturated hydro-
carbons. They showed positive color test for enolic
hydroxy group with an alcoholic solution of iron(III)
chloride. The IR spectra of IVa–IVe contained absorp-
tion bands belonging to stretching vibrations of the NH
group (3349–3360 cm–1), OH group (a broad band at
3165–3195 cm–1), lactam carbonyl groups C2′=O and
C4′=O in the pyrimidine fragment (1720–1742 cm–1),
lactam carbonyl groups C5=O and C6′=O in the pyrrole
fragments (1665–1676 cm–1), and benzoyl carbonyl
group (1618–1631 cm–1). Compounds IVa–IVe dis-
The formation of bridged tricyclic structure III may
be rationalized as follows. Initial addition of the C5
atom in the pyrimidine ring of II at the carbon atom in
position 2 of pyrroledione I gives intermediate A
which undergoes intramolecular nucleophilic attack by
the primary amino group in the pyrimidine ring on C4
in the pyrrole ring (Scheme 1). Analogous nucleophilic
[3+3]-addition was observed previously in the reaction
of pyrrolediones I with N-unsubstituted dimedone
imine, which occurred under milder conditions (on
heating in boiling anhydrous benzene over a period of
1–2 min) [4]. Presumably, the reaction described in the
present work requires more severe conditions due to
1
played in the H NMR spectra signals from protons in
the aromatic rings and substituents therein, two sing-
lets from methyl protons (δ 3.54–3.81 ppm), a singlet
from the NH proton (δ 10.56–10.79 ppm), and a sing-
let from the hydroxy proton (δ 12.02–12.21 ppm). The
following signals were observed in the 13C NMR spec-
trum of IVd, δC, ppm: 27.12 and 31.26 (Me), 55.19
(OMe), 70.67 (C2), 114.53 (C3); 114.54, 127.92, 128.49,
128.68, 128.76, 132.17, 134.01, 137.87 (Carom); 150.68
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 47 No. 6 2011

FIVE-MEMBERED 2,3-DIOXO HETEROCYCLES: LXXVI.
935
(C2′), 156.67 (C5), 158.85 (C4′), 166.39 (C6′), 175.79
(C4), 188.20 (PhCO). The spectral parameters of com-
pounds IVa–IVe were quite similar to those of model
3′-benzoyl-1-cyclohexyl-4′-hydroxy-6,6-dimethyl-1′-
phenyl-1,1′,2,2′,3,4,5,5′,6,7-octahydrospiro[indole-
3,2′-pyrrole]-2,4,5′-trione [8] and 3′-benzoyl-4′-hy-
droxy-11,11-dimethyl-1′-phenyl-1,2,2′,5′,10,11-hexa-
hydro-1′H-spiro[benzo[h]pyrrolo[2,1-a]isoquinoline-
2,2′-pyrrole]-1,5′-dione [9], whose structures were
proved by X-ray analysis.
61.24; H 4.50; N 11.41. C25H22N4O7. Calculated, %:
C 61.22; H 4.52; N 11.42.
Compounds IIIb–IIIe were synthesized in a similar
way.
Methyl 12-benzoyl-9-hydroxy-4,6-dimethyl-11-
(4-methylphenyl)-3,5,10-trioxo-4,6,8,11-tetraazatri-
cyclo[7.2.1.02,7]dodec-2(7)-ene-1-carboxylate (IIIb).
Yield 72%, mp 219–220°C (decomp., from 1,2-di-
chloroethane). IR spectrum, ν, cm–1: 3316 (NH),
3145 br (OH), 1760 (C5=O, C3=O), 1727 (C=O, ester),
1
1702 (C10=O), 1620 (COPh). H NMR spectrum, δ,
Presumably, heating of compounds IIIa–IIIe in
boiling xylene promotes cleavage of the hemiaminal
NH–C(OH) bond, followed by closure of new pyrrole
ring via intramolecular attack by the primary amino
group in the pyrimidine fragment on the ester carbonyl
carbon atom with elimination of methanol (Scheme 1).
Analogous heterocyclization of pyrrolediones I by the
action of acyclic and cyclic enamines was observed by
us previously most frequently [4, 5, 8, 9].
ppm: 2.28 s (3H, C6H4Me), 3.08 s and 3.14 s (3H each,
Me), 3.37 s (3H, OMe), 4.81 s (1H, 12-H), 7.08–
7.98 m (9H, Harom), 7.80 s (1H, OH), 8.49 s (1H, NH).
Found, %: C 61.85; H 4.84; N 11.13. C26H24N4O7. Cal-
culated, %: C 61.90; H 4.80; N 11.11.
Methyl 12-benzoyl-11-(4-chlorophenyl)-9-hy-
droxy-4,6-dimethyl-3,5,10-trioxo-4,6,8,11-tetraaza-
tricyclo[7.2.1.02,7]dodec-2(7)-ene-1-carboxylate
(IIIc). Yield 76%, mp 217–218°C (decomp., from
1,2-dichloroethane). IR spectrum, ν, cm–1: 3323 (NH),
3150 br (OH), 1760 (C5=O, C3=O), 1732 (C=O, ester),
EXPERIMENTAL
1
1705 (C10=O), 1620 (COPh). H NMR spectrum, δ,
The IR spectra were recorded on FSM-1201 and
Bruker IFS-66 spectrometers from samples dispersed
ppm: 3.10 s and 3.15 s (3H each, Me), 3.36 s (3H,
OMe), 4.85 s (1H, 12-H), 7.30–7.99 m (9H, Harom),
7.91 s (1H, OH), 8.56 s (1H, NH). Found, %: C 57.23;
H 4.06; Cl 6.71; N 10.63. C25H21ClN4O7. Calculated,
%: C 57.20; H 4.03; Cl 6.75; N 10.67.
1
in mineral oil. The H and 13C NMR spectra were
measured on a Bruker AM-400 spectrometer
1
(400 MHz for H) from solutions in DMSO-d6 using
tetramethylsilane as internal reference. The purity of
the isolated compounds was checked by TLC on
Silufol plates using ethyl acetate and ethyl acetate–
benzene (1:5) as eluent; spots were visualized by treat-
ment with iodine vapor.
Methyl 12-benzoyl-9-hydroxy-11-(4-methoxy-
phenyl)-4,6-dimethyl-3,5,10-trioxo-4,6,8,11-tetra-
azatricyclo[7.2.1.02,7]dodec-2(7)-ene-1-carboxylate
(IIId). Yield 69%, mp 219–220°C (decomp., from
1,2-dichloroethane). IR spectrum, ν, cm–1: 3340 (NH),
3158 br (OH), 1770 (C5=O, C3=O), 1730 (C=O, ester),
Methyl 12-benzoyl-9-hydroxy-4,6-dimethyl-
3,5,10-trioxo-11-phenyl-4,6,8,11-tetraazatricyclo-
[7.2.1.02,7]dodec-2(7)-ene-1-carboxylate (IIIa). A so-
lution of 1 mmol of compound Ia and 1 mmol of
aminouracil II in 10 ml of anhydrous 1,2-dichloro-
ethane was heated for 4 h under reflux. The mixture
was cooled, and the precipitate was filtered off. Yield
74%, mp 210–211°C (decomp., from 1,2-dichloro-
ethane). IR spectrum, ν, cm–1: 3330 (NH), 3160 br
(OH), 1759 (C5=O), 1738 (C3=O), 1721 (C=O, ester),
1
1710 (C10=O), 1625 (COPh). H NMR spectrum, δ,
ppm: 3.07 s and 3.13 s (3H each, Me), 3.38 s (3H,
COOMe), 3.74 s (3H, OMe), 4.80 s (1H, 12-H), 6.85–
7.98 m (9H, Harom), 7.96 s (1H, OH), 8.48 s (1H, NH).
Found, %: C 60.03; H 4.69; N 10.79. C26H24N4O8. Cal-
culated, %: C 60.00; H 4.65; N 10.76.
Methyl 12-benzoyl-11-(4-bromophenyl)-9-hy-
droxy-4,6-dimethyl-3,5,10-trioxo-4,6,8,11-tetraaza-
tricyclo[7.2.1.02,7]dodec-2(7)-ene-1-carboxylate
(IIIe). Yield 71%, mp 226–227°C (decomp., from
1,2-dichloroethane). IR spectrum, ν, cm–1: 3332 (NH),
3165 br (OH), 1760 (C5=O, C3=O), 1735 (C=O, ester),
1
1704 (C10=O), 1643 (COPh). H NMR spectrum, δ,
ppm: 3.09 s and 3.16 s (3H each, Me), 3.37 s (3H,
OMe), 4.83 s (1H, 12-H), 7.18–7.99 m (10H, Harom),
7.84 s (1H, OH), 8.52 s (1H, NH). 13C NMR spectrum,
δC, ppm: 27.73 and 30.14 (Me), 51.37 (C12), 54.70
(C1), 65.50 (MeO), 85.64 (C9), 125.43, 127.97, 128.87,
133.86, 137.33, 150.80 (C5), 157.85 (C2), 166.08
(C=O, ester), 167.05 (C10), 196.15 (PhCO). Found, %:
1
1709 (C10=O), 1622 (COPh). H NMR spectrum, δ,
ppm: 3.10 s and 3.15 s (3H each, Me), 3.36 s (3H,
OMe), 4.85 s (1H, 12-H), 7.25–7.99 m (9H, Harom),
7.91 s (1H, OH), 8.56 s (1H, NH). Found, %: C 52.71;
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 47 No. 6 2011

DENISLAMOVA et al.
936
H 3.79; Br 14.06; N 9.87. C25H21BrN4O7. Calculated,
%: C 52.74; H 3.72; Br 14.03; N 9.84.
13C NMR spectrum, δC, ppm: 27.12 and 31.26 (Me),
55.19 (OMe), 70.67 (C2), 114.53 (C3), 114.54, 127.92,
128.49, 128.68, 128.76, 132.17, 134.01, 137.87,
150.68 (C2′), 156.67 (C5), 158.85 (C4′), 166.39 (C6′),
175.79 (C4), 188.20 (PhCO). Found, %: C 61.49;
H 4.14; N 11.49. C25H20N4O7. Calculated, %: C 61.47;
H 4.13; N 11.47.
3-Benzoyl-4-hydroxy-1′,3′-dimethyl-1-phenyl-
spiro[pyrrole-2,5′-pyrrolo[2,3-d]pyrimidine]-
2′,4′,5,6′(1H,1′H,3′H,7′H)-tetraone (IVa). A solution
of 0.5 mmol of compound IIIa in m-xylene was heated
for 16 h under reflux. After cooling, the precipitate was
filtered off. Yield 68%, mp 238–240°C (decomp., from
ethyl acetate). IR spectrum, ν, cm–1: 3355 (NH);
3185 br (OH); 1740, 1720, 1665 (C4′=O, C6′=O, C2′=O,
3-Benzoyl-1-(4-bromophenyl)-4-hydroxy-1′,3′-di-
methylspiro[pyrrole-2,5′-pyrrolo[2,3-d]pyrimidine]-
2′,4′,5,6′(1H,1′H,3′H,7′H)-tetraone (IVe). Yield
52%, mp 248–249°C (decomp., from ethyl acetate). IR
spectrum, ν, cm–1: 3360 (NH); 3165 br (OH); 1740,
1725, 1667 (C2′=O, C4′=O, C5=O, C6′=O); 1618
1
C5=O); 1630 (COPh). H NMR spectrum, δ, ppm:
3.60 s and 3.81 s (3H each, Me), 7.08–7.71 m (10H,
Harom), 10.67 s (1H, NH), 12.17 br.s (1H, OH). Found,
1
%: C 62.90; H 3.94; N 12.21. C24H18N4O6. Calculated,
%: C 62.88; H 3.96; N 12.22.
(COPh). H NMR spectrum, δ, ppm: 3.54 s and 3.60 s
(3H each, Me), 7.04–7.99 m (9H, Harom), 10.78 s (1H,
NH), 12.21 br.s (1H, OH). Found, %: C 53.67; H 3.21;
Br 14.88; N 10.44. C24H17BrN4O6. Calculated, %:
C 53.65; H 3.19; Br 14.87; N 10.43.
3-Benzoyl-4-hydroxy-1′,3′-dimethyl-1-(4-methyl-
phenyl)spiro[pyrrole-2,5′-pyrrolo[2,3-d]pyrimi-
dine]-2′,4′,5,6′(1H,1′H,3′H,7′H)-tetraone (IVb).
Yield 63%, mp 269–270°C (decomp., from ethyl
acetate). IR spectrum, ν, cm–1: 3352 (NH); 3195 br
(OH); 1735, 1724, 1668 (C2′=O, C4′=O, C5=O, C6′=O);
This study was performed under financial support
by the Ministry of Education and Science of the
Russian Federation (project no. 2.19.10).
1
1631 (COPh). H NMR spectrum, δ, ppm: 2.25 s (3H,
C6H4Me), 3.59 s and 3.80 s (3H each, Me), 6.94–
7.65 m (9H, Harom), 10.59 s (1H, NH), 12.10 br.s (1H,
OH). Found, %: C 63.52; H 4.29; N 11.83. C25H20N4O6.
Calculated, %: C 63.56; H 4.27; N 11.86.
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1
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Cl 7.15; N 11.40. C24H17ClN4O6. Calculated, %:
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Yield 52%, mp 283–284°C (decomp., from ethyl
acetate). IR spectrum, ν, cm–1: 3356 (NH); 3175 br
(OH); 1742, 1730, 1670 (C2′=O, C4′=O, C5=O, C6′=O);
1625 (COPh). H NMR spectrum, δ, ppm: 3.07 s and
3.59 s (3H each, Me), 3.75 s (3H, OMe), 6.77–7.71 m
(9H, Harom), 10.56 s (1H, NH), 12.02 br.s (1H, OH).
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1
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RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 47 No. 6 2011