Synthesis and structure of new 3-pyrazolinylcoumarins and 3-pyrazolinyl-2-quinolones

Article abstract of DOI:10.1007/s11172-008-0195-4

The reactions of substituted 3-cinnamoyl-4-hydroxycoumarins and 3-cinnamoyl-4-hydroxy-2-quinolones with different phenylhydrazines gave 3-hetaryl-1H-4,5-dihydropyrazoles. The product structures were studied by ¹H NMR spectroscopy and mass spect

Full text of DOI:10.1007/s11172-008-0195-4

Russian Chemical Bulletin, International Edition, Vol. 57, No. 7, pp. 1508—1515, July, 2008
1508
Synthesis and structure of new 3ꢀpyrazolinylcoumarins
and 3ꢀpyrazolinylꢀ2ꢀquinolones
V. F. Traven, A. V. Manaev, I. V. Voevodina, and I. N. Okhrimenko
D. I. Mendeleev Russian University of Chemical Technology,
9 Miusskaya pl., 125047 Moscow, Russian Federation.
Fax: +7 (495) 609 2964. Еꢀmail: traven@muctr.edu.ru
The reactions of substituted 3ꢀcinnamoylꢀ4ꢀhydroxycoumarins and 3ꢀcinnamoylꢀ4ꢀhydroxyꢀ2ꢀ
quinolones with different phenylhydrazines gave 3ꢀhetarylꢀ1Hꢀ4,5ꢀdihydropyrazoles. The product
structures were studied by 1H NMR spectroscopy and mass spectrometry. 4ꢀHydroxyꢀ3ꢀpyrazoꢀ
linylcoumarins exist in DMSO as two tautomers (4ꢀenol and chromaneꢀ2,4ꢀdione), while 4ꢀhydroxyꢀ
3ꢀpyrazolinylꢀ2ꢀquinolones exist only in the enol form.
Key words: 1Hꢀ4,5ꢀdihydropyrazoles, 4ꢀhydroxycoumarin, 4ꢀhydroxyꢀ2ꢀquinolone, aldol conꢀ
densation, tautomerism.
Derivatives of Δ1ꢀpyrazolines (1Hꢀ4,5ꢀdihydropyraꢀ
zoles) find extensive use as optical bleachers and fluoresꢀ
cent dyes.1 Their spectral properties depend appreciably
on the nature of substituents in positions 1 and 3.
In particular, 1,3,5ꢀtriarylꢀ1Hꢀ4,5ꢀdihydropyrazoles are
distinguished by high fluorescence with a quantum yield
of more than 0.8.2—5 Many pyrazolines also show various
pharmacological properties.6—12 Some of these comꢀ
pounds have neuroleptic, analgesic, antiinflammatory,
or antipyretic properties and some other exhibit antiꢀ
depressant effect and antibacterial activity. Some pyrazoꢀ
line derivatives are used as pesticides, fungicides, and
insecticides.
3ꢀHetarylꢀ1Hꢀ4,5ꢀdihydropyrazoles arouse particuꢀ
lar interest because the properties determined by the pyraꢀ
zoline fragment are combined with the features of the
corresponding hetarene.13,14 Therefore, it should be notꢀ
ed that 3ꢀ(4ꢀhydroxyꢀ3ꢀcoumarinyl)ꢀ1Hꢀ4,5ꢀdihydropyꢀ
razoles are structural analogs of 3ꢀsubstituted 4ꢀhydroxyꢀ
coumarins some representatives of which are effective
blood anticoagulants.
Meanwhile, the knowledge concerning 3ꢀcoumariꢀ
nylꢀ1Hꢀ4,5ꢀdihydropyrazoles is scarce, while data on
their 2ꢀquinolone analogs are totally missing. Only some
3ꢀ(3ꢀcoumarinyl)ꢀ1Hꢀ4,5ꢀdihydropyrazoles have been
prepared from the coumarin analogs of chalcones.15—17
Thus 5ꢀarylꢀ3ꢀ(3ꢀcoumarinyl)ꢀ1Hꢀ4,5ꢀdihydropyrazoles
were synthesized by the reaction of 3ꢀcinnamoylꢀ4ꢀhydrꢀ
oxycoumarins with hydrazine hydrate and phenylhydraꢀ
zine in the presence of piperidine in ethanol.15 Howꢀ
ever, the reliability of these results was not confirmed by
spectral data; moreover, the authors failed to choose
between two possible isomeric structures (A and B).
Results and Discussion
The small number of works dealing with the synthesis
and study of 3ꢀcoumarinylꢀ1Hꢀ4,5ꢀdihydropyrazoles is
due to poor reproducibility of the synthesis of coumarin
analogs of chalcones by condensation of 3ꢀacetylꢀ4ꢀhydrꢀ
oxycoumarin with aromatic aldehydes. Carrying out this
reaction in the presence of catalytic amounts of 10%
NaOH without a solvent18 and in chloroform in the presꢀ
ence of piperidine19 was reported. We were unable to
accomplish condensation in the presence of sodium hydrꢀ
oxide, while the reaction in the presence of piperidine
proved to be nonꢀversatile and was reproduced only in
low yields and only for some aldehydes.
Previously,20 we found that under acid catalysis,
the boron difluoride complex of 3ꢀacetylꢀ4ꢀhydroxycouꢀ
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1479—1486, July, 2008.
1066ꢀ5285/08/5707ꢀ1508 © 2008 Springer Science+Business Media, Inc.

New 3ꢀpyrazolinylcoumarins and 2ꢀquinolones
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 7, July, 2008
1509
marin 1 is smoothly converted into coumarin analogs of
chalcones 2 in which the lactone fragment of the couꢀ
marin nucleus is distinguished by enhanced stability
against hydrolysis. In the subsequent study of the reactivꢀ
ity of complex 1, we obtained new coumarin analogs of
chalcones 2 using acetic acid (in the presence of catalytic
amounts of sulfuric acid) or acetic anhydride as the solꢀ
vent (Scheme 1). Boron complexes of chalcone analogs 3
are formed as direct condensation products.
The success of the synthesis of 3ꢀcinnamoylꢀ4ꢀhydrꢀ
oxycoumarins according to Scheme 1 is due to the
properties of the 3ꢀacetylꢀ4ꢀhydroxycoumarin boron diꢀ
fluoride complex. As shown previously,21 the complexꢀ
ation of 3ꢀacetylꢀ4ꢀhydroxycoumarin with BF3 increases
considerably the C=O bond length (from 1.252 to
1.285 Å) and shortens the C(=O)—CH3 bond (from
1.492 to 1.476 Å). These changes in the bond lengths
correspond to the structural change of the acetyl group
toward enolization, which leads to an increase in the
reaction rate between the enol formed and aldehyde.
The reaction of substituted 3ꢀcinnamoylꢀ4ꢀhydroxyꢀ
coumarins 2 with substituted phenylꢀ and hetarylhydrꢀ
azines in isopropyl alcohol smoothly gives 1,5ꢀdiarylꢀ3ꢀ
(4ꢀhydroxyꢀ3ꢀcoumarinyl)ꢀ1Hꢀ4,5ꢀdihydropyrazoles 4
(Scheme 2).
signals at δ 7.5—8.5 for H(9) and H(10) protons with
spinꢀspin coupling constants of 15.2—15.7 Hz; this corꢀ
responds to the Eꢀconfiguration of the crotonic condenꢀ
sation products 2. The H NMR spectra of compounds
4a—n exhibit also signals for protons at C(9) and C(10) as
doublets of doublets or multiplets.
Compounds 4a,f have been described previously;15
however, their spectral characteristics were not reported
and our data on the melting points of these compounds do
not coincide with published data.
1
Since both the spectral properties and the biological
activities of 3ꢀsubstituted 4ꢀhydroxycoumarins are deterꢀ
mined by the type of tautomeric form in which they exist,
we studied the dependence of chemical shifts in the
1H NMR spectra of new 1,5ꢀdiarylꢀ3ꢀ(4ꢀhydroxyꢀ3ꢀcouꢀ
marinyl)ꢀ1Hꢀ4,5ꢀdihydropyrazoles 4a—n on the solvent.
The spectra recorded in deuterated DMSO and chloroꢀ
form attest to the ability of 3ꢀ(4ꢀhydroxyꢀ3ꢀcoumarinyl)ꢀ
1Hꢀ4,5ꢀdihydropyrazoles to exist in at least two tautoꢀ
1
meric forms. Thus the H NMR spectrum of pyrazoline
4b recorded in a nonpolar solvent (CDCl3) exhibits only
one lowꢀfield signal (δ 13.98), which belongs to the hyꢀ
droxyl group present in the enol form C of pyrazoline 4
1
(Fig. 1). In the H NMR spectrum of pyrazoline 4b reꢀ
corded in a polar solvent (DMSO), an additional signal
corresponding to the NH group appears at δ 10.32 apart
from the OH signal (δ 13.74). From comparison of the
integral intensities of these signals, one can conclude that
All new compounds were characterized by the
1H NMR spectra, mass spectra, and elemental analysis
1
data. The H NMR spectra of compounds 2a—q exhibit
Scheme 1

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Russ.Chem.Bull., Int.Ed., Vol. 57, No. 7, July, 2008
Traven et al.
Scheme 2
Scheme 3
most stable form (Scheme 3), as the calculated enthalpy of
its formation is the lowest almost for all structures. Pyraꢀ
zolines 4e and 4i containing a pꢀnitrophenyl substituent at
N(1) are exceptions. The difference between the formation
energies of tautomers C and D decreases for these pyrazoꢀ
lines to 6.27—6.38 kcal mol–1
.
2ꢀQuinolone analogs of compounds 4 were obtained
in the same way (Scheme 4). As we reported previously,22
acidꢀcatalyzed reactions of boron difluoride complex of
3ꢀacetylꢀ4ꢀhydroxyꢀ1ꢀmethylꢀ2ꢀquinolone with aromaꢀ
tic and heterocyclic aldehydes afford boron difluoride
complexes of 3ꢀcinnamoylꢀsubstituted derivatives of
4ꢀhydroxyꢀ2ꢀquinolone in high yields. They are hydrꢀ
olyzed to give heterocyclic analogs of chalcones 5a,b in
a quantitative yield.
Compounds 5a,b react with phenylhydrazine in acetic
acid or with phenylhydrazine hydrochlorides in isoproꢀ
4
a
b
c
d
e
f
R1
H
H
H
H
R2
OMe
OMe
OMe
OMe OMe
OMe
R3
H
F
4
g
h
i
j
k
l
R1
R2
R3
F
Me
NO2
H
OMe OMe
OMe OMe
OMe OMe
H
H
H
a
Me
NMe2
NMe2
NMe2 OMe
H
NO2
H
F
OMe OMe
13.74
10.32
4: R = H (m), OMe (n)
compound 4b exists in DMSO as chromaneꢀ2,4ꢀdione D
by 45% and as enol C by 55%.
b
13.98
According to results of AM1 semiempirical quantum
chemical calculations, the interconversions of the tautoꢀ
mers C and D of 3ꢀ(4ꢀhydroxyꢀ3ꢀcoumarinyl)ꢀ1Hꢀ4,5ꢀ
dihydropyrazoles are most probable as the difference betꢀ
ween their formation enthalpies is small (1—3 kcal mol–1).
The formation enthalpies ΔHf° of the tautomers of comꢀ
pounds 4a—l imply that chromaneꢀ2,4ꢀdione D is the
14
12
10
8
6
4
δ
Fig. 1. 1H NMR spectra of compound 4b recorded in DMSOꢀd6 (a)
and CDCl3 (b).

New 3ꢀpyrazolinylcoumarins and 2ꢀquinolones
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 7, July, 2008
1511
Scheme 4
5ꢀsubstituted pyrazolines as doublets of doublets with δ of
3.5 to 6.0.
Experimental
1
H NMR spectra were recorded on a Bruker WPꢀ400 SY specꢀ
trometer (400 MHz) with Me4Si as the internal standard. LC/MS
analysis was performed on a PE SCIEX API165 spectrometer (ELSD
UV254) with a Synergi 2u HydroꢀRP Mercury column (20×2.0
mm).
Condensation of boron complex 1 with aldehydes. A. A solution
of aldehyde (4 mmol) in acetic anhydride (2 mL) was added at 60 °C
to a solution of boron difluoride complex of 3ꢀacetylꢀ4ꢀhydroxyꢀ
coumarin 1 21 (4 mmol) in acetic anhydride (10 mL). The mixture
was heated for 30 min at 90 °C. After cooling, the precipitate was
filtered off, washed on the filter with acetic acid, dried, and recrysꢀ
tallized from acetic acid.
B.A solution of aldehyde (4 mmol) in acetic acid (2 mL) was added
at 60 °C to a solution of boron complex 1 (4 mmol) in glacial acetic
acid (6 mL), and then concentrated H2SO4 (0.5 mL) was added.
The mixture was refluxed for 30 min. After cooling, the precipitate
was filtered off, washed on the filter with acetic acid, and dried in air.
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(3ꢀethoxyꢀ4ꢀhydroxyphenyl)ꢀ
propꢀ2ꢀenoyl]coumarin (3a). Yield 79% (method B), m.p. 160—162 °C.
1H NMR (CDCl3), δ: 1.50 (t, 3 H, OCH2CH3, J = 7.2 Hz); 4.26
(q, 2 H, OCH2CH3, J = 7.2 Hz); 7.05 (d, 1 H, H(12), J = 8.2 Hz);
7.23—7.51 (m, 3 H, H(6), H(8), H(15)); 7.80 (m, 1 H, H(7)); 8.26
(d, 1 H, H(5), J = 6.9 Hz); 8.42 (d, 1 H, H(10), J = 15.4 Hz); 8.47
(d, 1 H, H(9), J = 15.4 Hz); 9.15 (s, 1 H, OH). MS, m/z (Irel (%)):
400 (75). Found (%): C, 59.83; H, 3.81. C20H15BF2O6. Calculatꢀ
ed (%): C, 60.00; H, 3.75.
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(2ꢀhydroxyꢀ3ꢀmethoxyphenyl)ꢀ
propꢀ2ꢀenoyl]coumarin (3b). Yield 87% (method B), m.p. 228—230 °C.
1H NMR (CDCl3), δ: 4.26 (s, 3 H, OCH3); 7.20—7.38 (m, 5 H,
H(6), H(8), H(12), H(14), H(15)); 7.76 (m, 1 H, H(7)); 8.15 (d, 1 H,
H(5), J = 6.8 Hz); 8.32 (m, 2 H, H(9), H(10)); 9.25 (s, 1 H, OH).
MS, m/z (Irel (%)): 386 (85). Found (%): C, 59.21; H, 3.24.
C19H13BF2O6. Calculated (%): C, 59.07; H, 3.37.
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(2ꢀhydroxyꢀ4ꢀmethoxyphenyl)ꢀ
propꢀ2ꢀenoyl]coumarin (3c). Yield 61% (method B), m.p. 120—122 °C.
1H NMR (CDCl3), δ: 3.94 (s, 3 H, OCH3); 6.12 (s, 1 H, H(12));
7.06—7.31 (m, 4 H, H(6), H(8), H(11), H(14)); 7.81 (m, 1 H,
H(7)); 8.07 (d, 1 H, H(5), J = 6.4 Hz); 8.21 (m, 2 H, H(9), H(10));
9.42 (s, 1 H, OH). MS, m/z (Irel (%)): 386 (70). Found (%):
C, 58.91; H, 3.45. C19H13BF2O6. Calculated (%): C, 59.07; H, 3.37.
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(4ꢀhydroxyꢀ3,5ꢀdimethoxypheꢀ
nyl)propꢀ2ꢀenoyl]coumarin (3d). Yield 65% (method B), m.p.
230—232 °C. 1H NMR (CDCl3), δ: 3.95 (s, 6 H, 2 OCH3); 7.09
(s, 2 H, H(11), H(15)); 7.41 (m, 2 H, H(6), H(8)); 7.84 (m, 1 H,
H(7)); 7.96 (d, 1 H, H(5), J = 6.5 Hz); 8.41 (d, 1 H, H(10),
J = 15.2); 8.47 (d, 1 H, H(9), J = 15.2); 9.26 (s, 1 H, OH). MS, m/z
(Irel (%)): 416 (82). Found (%): C, 57.51; H, 3.74. C20H15BF2O7.
Calculated (%): C, 57.69; H, 3.61.
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(3ꢀhydroxyꢀ4ꢀmethoxyphenyl)ꢀ
propꢀ2ꢀenoyl]coumarin (3e). Yield 78% (method B), m.p. 175—177 °C.
1H NMR (CDCl3), δ: 4.05 (s, 3 H, OCH3); 6.84 (s, 1 H, H(15));
7.09 (d, 1 H, H(12), J = 7.8 Hz); 7.24—7.39 (m, 3 H, H(6), H(8),
H(11)); 7.76 (m, 1 H, H(7)); 7.96 (d, 1 H, H(5), J = 6.5 Hz); 8.41
(d, 1 H, H(10), J = 15.2 Hz); 8.47 (d, 1 H, H(9), J = 15.2 Hz); 9.26
(s, 1 H, OH). MS, m/z (Irel (%)): 386 (75). Found (%): C, 59.19;
H, 3.45. C19H13BF2O6. Calculated (%): C, 59.07; H, 3.37.
6: R = H (a), F (b, d), OMe (c, e)
pyl alcohol in the presence of KOH to give compounds
6a—e in high yields (see Scheme 4). The structures of
obtained compounds were proved by NMR spectroscopy,
mass spectrometry, and elemental analysis. The 1H NMR
spectra of all compounds exhibit a narrow signal at δ 13.5
for the hydroxyl proton, the signal position and form
remaining invariable for different solvents (DMSOꢀd6
and CDCl3). This fact indicates that unlike coumarin
analogs 4a—l, compounds 6a—e are by 100% the hydroxy
form in these solvents. As the spectra of compounds
1
4a—l, the H NMR spectra of compounds 6a—e contain
signals for three protons (2 H(9) and H(10)) typical of

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Traven et al.
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(3ꢀethoxyꢀ2ꢀhydroxyphenyl)ꢀ
propꢀ2ꢀenoyl]coumarin (3f). Yield 64% (method B), m.p. 189—191 °C.
1H NMR (CDCl3), δ: 2.94 (t, 3 H, OCH2CH3, J = 7.4 Hz); 3.98
(q, 2 H, OCH2CH3, J = 7.4 Hz); 7.02—7.36 (m, 5 H, H(6), H(8),
H(13), H(14), H(15)); 7.62 (m, 1 H, H(7)); 7.91 (d, 1 H, H(5),
J = 6.4 Hz); 8.09 (m, 2 H, H(9), H(10)); 8.31 (s, 1 H, OH). MS, m/z
(Irel (%)): 400 (95). Found (%): C, 59.79; H, 3.81. C20H15BF2O6.
Calculated (%): C, 60.01; H, 3.75.
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(4ꢀhydroxyꢀ2ꢀmethoxyphenyl)ꢀ
propꢀ2ꢀenoyl]coumarin (3g). Yield 87% (method B), m.p. 228—230 °C.
1H NMR (CDCl3), δ: 4.23 (s, 3 H, OCH3); 7.17—7.41 (m, 5 H,
H(6), H(8), H(12), H(14), H(15)); 7.75 (m, 1 H, H(7)); 8.13 (d, 1 H,
H(5), J = 6.8 Hz); 8.31 (m, 2 H, H(9), H(10)); 9.23 (s, 1 H, OH).
MS, m/z (Irel (%)): 386 (85). Found (%): C, 59.18; H, 3.49.
C19H13BF2O6. Calculated (%): C, 59.07; H, 3.37.
4ꢀDifluoroboryloxyꢀ3ꢀ{(E)ꢀ3ꢀ[4ꢀ(N,Nꢀdiethylamino)ꢀ2ꢀhydrꢀ
oxyphenyl]propꢀ2ꢀenoyl}coumarin (3h). Yield 58% (method A),
m.p. 182—184 °C. 1H NMR (CDCl3), δ: 1.27 (t, 6 H, 2 CH2CH3);
3.48 (q, 4 H, 2 CH2CH3); 6.43 (s, 1 H, H(12)); 6.64 (d, 1 H, H(14),
J = 9.3 Hz); 7.32 (m, 2 H, H(6), H(8)); 7.73 (m, 2 H, H(7),
H(15)); 8.21 (d, 1 H, H(5), J = 9.3 Hz); 8.34 (d, 1 H, H(10),
J = 15.4 Hz); 8.53 (d, 1 H, H(9), J = 15.4 Hz); 8.87 (s, 1 H, OH).
MS, m/z (Irel (%)): 411 (65). Found (%): C, 64.81; H, 4.71; N, 3.49.
C22H20BF2NO4. Calculated (%): C, 64.23; H, 4.87; N, 3.41.
4ꢀDifluoroboryloxyꢀ3ꢀ{(E)ꢀ3ꢀ[4ꢀ(7ꢀhydroxyoctyl)phenyl]propꢀ
2ꢀenoyl}coumarin (3i). Yield 82% (method B), m.p. 149—151 °C.
1H NMR (CDCl3), δ: 2.43 (m, 14 H, CH2C7H14); 3.96 (t, 2 H,
CH2C7H14, J = 6.1 Hz); 6.89 (d, 2 H, H(11), H(15), J = 8.3 Hz);
7.32 (m, 2 H, H(6), H(8)); 7.65 (m, 3 H, H(7), H(12), H(14)); 8.03
(m, 3 H, H(5), H(9), H(10)); 8.87 (s, 1 H, OH). MS, m/z (Irel (%)):
468 (75). Found (%): C, 66.45; H, 3.71. C26H27BF2O5. Calculatꢀ
ed (%): C, 66.67; H, 3.63.
308—310 °C. 1H NMR (CDCl3), δ: 3.43 (s, 6 H, 2 CH3); 6.97
(d, 1 H, H(12), J = 5.1 Hz); 7.23 (d, 1 H, H(10), J = 12.9 Hz); 7.42
(m, 2 H, H(6), H(8)); 7.78 (m, 1 H, H(7)); 7.97 (d, 1 H, H(5),
J = 6.5 Hz); 8.10 (d, 1 H, H(11), J = 5.1 Hz); 8.29 (d, 1 H, H(9),
J = 12.9 Hz). MS, m/z (Irel (%)): 389 (76). Found (%): C, 55.81;
H, 3.52; N, 3.69. C18H14BF2NO4S. Calculated (%): C, 55.53;
H, 3.60; N, 3.60.
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(5ꢀpyrrolidinoꢀ2ꢀthienyl)propꢀ2ꢀ
enoyl]coumarin (3p). Yield 79% (method A), m.p. 310—312 °C. The
1H NMR spectrum could not be recorded due to poor solubility in
CDCl3. MS, m/z (Irel (%)): 401 (65). Found (%): C, 59.71; H, 3.92.
C20H16BF2O4S. Calculated (%): C, 59.85; H, 3.99.
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(1ꢀethylꢀ1,2,3,4ꢀtetrahydroꢀ
quinolinꢀ6ꢀyl)propꢀ2ꢀenoyl]coumarin (3q). Yield 83% (method A),
m.p. 252—254 °C. 1H NMR (CDCl3), δ: 1.29 (t, 3 H, CH2CH3,
J = 7.4 Hz); 2.01 (q, 2 H, CH2CH3, J = 7.4 Hz); 2.77 (m, 2 H,
H(14)); 3.52 (m, 4 H, H(12), H(13)); 6.64 (d, 1 H, H(15),
J = 8.8 Hz); 7.23—7.45 (m, 2 H, H(11), H(16)); 7.56 (m, 2 H,
H(6), H(8)); 7.74 (m, 1 H, H(7)); 8.22 (m, 2 H, H(6), H(10)); 8.48
(d, 1 H, H(9), J = 15.1 Hz). MS, m/z (Irel (%)): 423 (80). Found (%):
C, 65.38; H, 4.79; N, 3.26. C23H20BF2NO4. Calculated (%):
C, 65.25; H, 4.73; N, 3.31.
Hydrolysis of boron complexes 3 (general procedure). Boron
complex 3 (0.5 g) was dissolved in ethanol (5 mL) in a singleꢀneck
flask equipped with a reflux condenser. Water (5 mL) and a 5—10ꢀfold
molar excess of Na2CO3 were added. The mixture was heated at
reflux until the color of the boron complex disappeared. Then
the reaction mixture was cooled and carefully acidified. The precipꢀ
itate was filtered off, washed, and dried.
4ꢀHydroxyꢀ3ꢀ[(E)ꢀ3ꢀ(3ꢀethoxyꢀ4ꢀhydroxyphenyl)propꢀ2ꢀenoꢀ
yl]coumarin (2a). Yield 96%, m.p. 123—125 °C (cf. Ref. 23: m.p.
125 °C).
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(4ꢀmethoxyphenyl)propꢀ2ꢀenoꢀ
yl]coumarin (3j). Yield 84% (method B), m.p. 194—196 °C
(cf. Ref. 20: m.p. 194—196 °C).
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(2,4ꢀdimethoxyphenyl)propꢀ2ꢀ
enoyl]coumarin (3k). Yield 76% (method B), m.p. 272—274 °C
(cf. Ref. 20: m.p. 273—274 °C).
4ꢀDifluoroboryloxyꢀ3ꢀ{(E)ꢀ3ꢀ[4ꢀ(N,Nꢀdimethylamino)phenyl]ꢀ
propꢀ2ꢀenoyl}coumarin (3l). Yield 87% (method A), m.p. 331—333 °C
(cf. Ref. 20: m.p. 332—333 °C).
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(5ꢀpiperidinoꢀ2ꢀthienyl)propꢀ2ꢀ
enoyl]coumarin (3m). Yield 67% (method A), m.p. 303—305 °C.
1H NMR (CDCl3), δ: 1.62 (m, 6 H, H(14), H(15), H(16)); 3.83
(t, 4 H, H(13), H(17), J = 9.2 Hz); 7.13 (d, 1 H, H(12), J = 5.5 Hz);
7.19 (d, 1 H, H(10), J = 14.8 Hz); 7.44 (m, 2 H, H(6), H(8)); 7.78
(m, 1 H, H(7)); 7.97 (d, 1 H, H(5), J = 6.9 Hz); 8.12 (d, 1 H, H(11),
J = 5.5 Hz); 8.29 (d, 1 H, H(9), J = 14.8 Hz). MS, m/z (Irel (%)):
429 (82). Found (%): C, 58.41; H, 4.32; N, 3.15. C21H18BF2NO4S.
Calculated (%): C, 58.74; H, 4.20; N, 3.26.
4ꢀDifluoroboryloxyꢀ3ꢀ[(E)ꢀ3ꢀ(5ꢀmorpholinoꢀ2ꢀthienyl)propꢀ
2ꢀenoyl]coumarin (3n). Yield 65% (method A), m.p. 321—323 °C.
1H NMR (CDCl3), δ: 3.82 (m, 8 H, H(13), H(14)), H(15), H(16));
7.07 (d, 1 H, H(12), J = 5.1 Hz); 7.26 (d, 1 H, H(10), J = 12.9 Hz);
7.44 (m, 2 H, H(6), H(8)); 7.78 (m, 1 H, H(7)); 7.98 (d, 1 H, H(5),
J = 6.8 Hz); 8.11 (d, 1 H, H(11), J = 5.1 Hz); 8.35 (d, 1 H, H(9),
J = 12.9 Hz). MS, m/z (Irel (%)): 431 (65). Found (%): C, 55.32;
H, 3.58; N, 3.17. C20H16BF2NO5S. Calculated (%): C, 55.68;
H, 3.71; N, 3.25.
4ꢀHydroxyꢀ3ꢀ[(E)ꢀ3ꢀ(2ꢀhydroxyꢀ3ꢀmethoxyphenyl)propꢀ2ꢀ
enoyl]coumarin (2b). Yield 97%, m.p. 150—153 °C. 1H NMR
(DMSOꢀd6), δ: 3.84 (s, 3 H, OCH3); 6.89 (m, 1 H, H(14)); 7.08
(d, 1 H, H(13), J = 7.4 Hz); 7.24 (d, 1 H, H(15), J = 7.9 Hz); 7.43
(m, 2 H, H(6), H(8)); 7.82 (m, 1 H, H(7)); 8.07 (d, 1 H, H(5),
J = 6.5 Hz); 8.36 (m, 2 H, H(9), H(10)); 9.66 (s, 1 H, OH(11));
18.21 (s, 1 H, OH(4)). MS, m/z (Irel (%)): 338 (93). Found (%):
C, 67.72; H, 4.25. C19H14O6. Calculated (%): C, 67.45; H, 4.14.
4ꢀHydroxyꢀ3ꢀ[(E)ꢀ3ꢀ(2ꢀhydroxyꢀ4ꢀmethoxyphenyl)propꢀ2ꢀenoꢀ
yl]coumarin (2c). Yield 95%, m.p. 184—186 °C. 1H NMR (DMSOꢀd6),
δ: 3.81 (s, 3 H, OCH3); 6.57 (m, 2 H, H(12), H(14)); 7.42 (m, 3 H,
H(6), H(8), H(15)); 7.59 (d, 1 H, H(10), J = 15.7 Hz); 7.82 (m, 2 H,
H(7), H(9)); 8.04 (d, 1 H, H(5), J = 6.9 Hz); 8.31 (s, 1 H, OH(11));
18.6 (s, 1 H, OH(4)). MS, m/z (Irel (%)): 338 (89). Found (%):
C, 67.91; H, 4.29. C19H14O6. Calculated (%): C, 67.45; H, 4.14.
4ꢀHydroxyꢀ3ꢀ[(E)ꢀ3ꢀ(4ꢀhydroxyꢀ3,5ꢀdimethoxyphenyl)propꢀ
2ꢀenoyl]coumarin (2d). Yield 98%, m.p. >350 °C. 1H NMR
(DMSOꢀd6), δ: 3.57 (s, 6 H, 2 OCH3); 6.72 (s, 2 H, H(11), H(15));
7.41—7.63 (m, 5 H, H(6), H(7), H(8), H(9), H(10)); 7.94 (d, 1 H,
H(5), J = 7.9 Hz); 8.20 (s, 1 H, OH(13)); 18.92 (s, 1 H, OH(4)).
MS, m/z (Irel (%)): 368 (95). Found (%): C, 65.43; H, 4.26.
C20H16O7. Calculated (%): C, 65.22; H, 4.35.
4ꢀHydroxyꢀ3ꢀ[(E)ꢀ3ꢀ(3ꢀhydroxyꢀ4ꢀmethoxyphenyl)propꢀ2ꢀ
enoyl]coumarin (2e). Yield 96%, m.p. 119—120 °C. 1H NMR
(DMSOꢀd6), δ: 3.85 (s, 3 H, OCH3); 6.84 (d, 1 H, H(12), J = 8.7 Hz);
7.13 (d, 1 H, H(11), J = 8.7 Hz); 7.28 (m, 3 H, H(6), H(8), H(15));
7.63 (m, 1 H, H(7)); 7.94 (d, 1 H, H(10), J = 15.3 Hz); 8.05 (d, 1
H, H(4), J = 7.6 Hz); 8.22 (d, 1 H, H(9), J = 15.3 Hz); 9.14 (s, 1 H,
OH(13)); 17.63 (s, 1 H, OH(4)). MS, m/z (Irel (%)): 338 (95).
4ꢀDifluoroboryloxyꢀ3ꢀ{(E)ꢀ3ꢀ[5ꢀ(N,Nꢀdimethylamino)ꢀ2ꢀthieꢀ
nyl]propꢀ2ꢀenoyl}coumarin (3o). Yield 63% (method A), m.p.

New 3ꢀpyrazolinylcoumarins and 2ꢀquinolones
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 7, July, 2008
1513
Found (%): C, 67.73; H, 4.02. C19H14O6. Calculated (%): C, 67.45;
H, 4.14.
4ꢀHydroxyꢀ3ꢀ{(E)ꢀ3ꢀ[5ꢀ(N,Nꢀdimethylamino)ꢀ2ꢀthienyl]propꢀ
2ꢀenoyl}coumarin (2o). Yield 96%, m.p. 244—246 °C. H NMR
1
3ꢀ[(E)ꢀ3ꢀ(3ꢀEthoxyꢀ2ꢀhydroxyphenyl)propꢀ2ꢀenoyl]ꢀ4ꢀhydrꢀ
oxycoumarin (2f). Yield 95%, m.p. 199—201 °C. 1H NMR (DMSOꢀd6),
δ: 1.37 (t, 3 H, OCH2CH3, J = 6.9 Hz); 4,10 (q, 2 H, OCH2CH3,
J = 6.9 Hz); 6.87 (m, 1 H, H(14)); 7.08 (d, 1 H, H(13), J = 8.3 Hz);
7.22 (d, 1 H, H(15), J = 7.9 Hz); 7.43 (m, 2 H, H(6), H(8)); 7.81
(m, 1 H, H(7)); 8.04 (d, 1 H, H(5), J = 6.9 Hz); 8,35 (m, 2 H, H(9),
H(10)); 9,48 (s, 1 H, OH(11)); 18,06 (s, 1 H, OH(4)). MS, m/z
(Irel (%)): 352 (90). Found (%): C, 68.35; H, 4.41. C20H16O6.
Calculated (%): C, 68.18; H, 4.55.
4ꢀHydroxyꢀ3ꢀ[(E)ꢀ3ꢀ(4ꢀhydroxyꢀ2ꢀmethoxyphenyl)propꢀ2ꢀ
enoyl]coumarin (2g). Yield 97%, m.p. 150—153 °C. 1H NMR
(DMSOꢀd6), δ: 3.81 (s, 3 H, OCH3); 6.87 (s, 1 H, H(12)); 7.05
(d, 1 H, H(14), J = 7.4 Hz); 7.22 (d, 1 H, H(15), J = 7.9 Hz); 7.41
(m, 2 H, H(6), H(8)); 7.80 (m, 1 H, H(7)); 8.04 (d, 1 H, H(4),
J = 6.5 Hz); 8.33 (m, 2 H, H(9), H(10)); 9.64 (s, 1 H, OH(11));
18.22 (s, 1 H, OH(4)). MS, m/z (Irel (%)): 338 (93). Found (%):
C, 67.29; H, 4.07. C19H14O6. Calculated (%): C, 67.45; H, 4.14.
3ꢀ{(E)ꢀ3ꢀ[4ꢀ(N,NꢀDiethylamino)ꢀ2ꢀhydroxyphenyl]propꢀ2ꢀ
enoyl}ꢀ4ꢀhydroxycoumarin (2h). Yield 92%, m.p. 194—196 °C.
1H NMR (DMSOꢀd6), δ: 1.10 (t, 6 H, 2 CH2CH3, J = 6.9 Hz);
3.41 (q, 4 H, 2 CH2CH3, J = 6.9 Hz); 6.25 (s, 1 H, H(12)); 6.46
(d, 1 H, H(14), J = 8.3 Hz); 7.41 (m, 3 H, H(6), H(8), H(15)); 7.76
(m, 1 H, H(7)); 8.02 (d, 1 H, H(5), J = 7.8 Hz); 8.11 (d, 1 H, H(10),
J = 15.2 Hz); 8.40 (d, 1 H, H(9), J = 15.2 Hz); 10.53 (s, 1 H,
OH(11)); 17.69 (s, 1 H, OH(4)). MS, m/z (Irel (%)): 363 (95).
Found (%): C, 72.21; H, 6.03; N, 3.71 C22H21NO4. Calculatꢀ
ed (%): C, 72.42; H, 5.91; N, 3.86.
4ꢀHydroxyꢀ3ꢀ{(E)ꢀ3ꢀ[4ꢀ(7ꢀhydroxyoctyl)phenyl]propꢀ2ꢀenoꢀ
yl}coumarin (2i). Yield 95%, m.p. 99—101 °C. 1H NMR (DMSOꢀd6),
δ: 2.48 (m, 14 H, CH2C7H14); 4.06 (t, 2 H, CH2C7H14, J = 6.7 Hz);
7.07 (d, 2 H, H(12), H(14), J = 8.1 Hz); 7.41 (m, 2 H, H(6), H(8));
7.76 (m, 3 H, H(7), H(11), H(15)); 8.09 (m, 3 H, H(5), H(9),
H(10)); 9.12 (s, 1 H, OH); 18.61 (s, 1 H, OH(4)). MS, m/z (Irel (%)):
420 (85). Found (%): C, 74.43; H, 6.77. C26H28O5. Calculatꢀ
ed (%): C, 74.29; H, 6.67.
4ꢀHydroxyꢀ3ꢀ[(E)ꢀ3ꢀ(4ꢀmethoxyphenyl)propꢀ2ꢀenoyl]coumꢀ
arin (2j). Yield 96%, m.p. 185—186 °C (cf. Ref. 18: m.p. 184 °C).
3ꢀ[(E)ꢀ3ꢀ(2,4ꢀDimethoxyphenyl)propꢀ2ꢀenoyl]ꢀ4ꢀhydroxyꢀ
coumarin (2k). Yield 98%, m.p. 143—144 °C (cf. Ref. 20: m.p.
143—144 °C).
(DMSOꢀd6), δ: 3.27 (s, 6 H, 2 CH3); 6.43 (d, 1 H, H(12), J = 4.6 Hz);
7.37 (m, 3 H, H(6), H(8), H(10)); 7.72 (m, 2 H, H(7), H(11)); 7.98
(d, 1 H, H(5), J = 9.7 Hz); 8.23 (d, 1 H, H(9), J = 14.3 Hz); 18.87
(s, 1 H, OH). MS, m/z (Irel (%)): 341 (85). Found (%): C, 63.51;
H, 4.29; N, 4.16. C18H15NO4S. Calculated (%): C, 63.34; H, 4.40;
N, 4.11.
4ꢀHydroxyꢀ3ꢀ[(E)ꢀ3ꢀ(5ꢀpyrrolidinoꢀ2ꢀthienyl)propꢀ2ꢀenoyl]ꢀ
coumarin (2p). Yield 98%, m.p. 225—227 °C. 1H NMR (DMSOꢀd6),
δ: 2.13 (m, 4 H, H(13), H(16)); 3.44 (m, 4 H, H(14), H(15)); 5.91
(d, 1 H, H(12), J = 4.6 Hz); 7.16—7.38 (m, 3 H, H(6), H(8),
H(11)); 7.62 (m, 2 H, H(7), H(10); 8.05 (d, 1 H, H(5), J = 6.5 Hz);
8.19 (d, 1 H, H(9), J = 15.2 Hz); 17.63 (s, 1 H, OH). MS, m/z
(Irel (%)): 367 (70). Found (%): C, 65.29; H, 4.58; N, 3.74.
C20H17NO5S. Calculated (%): C, 65.40; H, 4.63; N, 3.81.
3ꢀ[(E)ꢀ3ꢀ(1ꢀEthylꢀ1,2,3,4ꢀtetrahydroquinolinꢀ6ꢀyl)propꢀ2ꢀ
enoyl]ꢀ4ꢀhydroxycoumarin (2q). Yield 96%, m.p. 194—196 °C.
1H NMR (DMSOꢀd6), δ: 1.20 (t, 3 H, CH2CH3, J ≈ 7 Hz); 1.98
(q, 2 H, CH2CH3, J ≈ 7 Hz); 2.79 (m, 2 H, H(13)); 3.41 (m, 4 H,
H(12), H(14)); 6.58 (d, 1 H, H(15), J = 8.6 Hz); 7.29 (m, 2 H,
H(11), H(16)); 7.44 (m, 2 H, H(6), H(8)); 7.63 (m, 1 H, H(7));
8.12 (m, 3 H, H(5), H(9), H(10)); 18.75 (s, 1 H, OH). MS, m/z
(Irel (%)): 375 (85). Found (%): C, 73.48; H, 5.66; N, 3.79.
C23H21NO5S. Calculated (%): C, 73.60; H, 5.60; N, 3.73.
Synthesis of 4ꢀhydroxyꢀ3ꢀpyrazolinylcoumarins 4 (general
procedure). A 3—4ꢀfold molar excess of phenylhydrazine hydroꢀ
chloride and KOH (0.3 g) were added at reflux to a suspension of
3ꢀcinnamoylꢀ4ꢀhydroxycoumarin 2 (0.5 g) in isopropyl alcohol
(30 mL). The mixture was refluxed for 1 h, cooled, and filtered. The
resulting precipitate was recrystallized from alcohol.
4ꢀHydroxyꢀ3ꢀ[5ꢀ(4ꢀmethoxyphenyl)ꢀ1ꢀphenylꢀ4,5ꢀdihydroꢀ
1Hꢀpyrazolꢀ3ꢀyl]coumarin (4a). Yield 73%, m.p. 181—183 °C
(cf. Ref. 15: m.p. 196 °C). 1H NMR (DMSOꢀd6), δ: 3.36 (dd, 1 H,
H(9), J = 18.4 Hz, J = 6.9 Hz); 3.74 (s, 3 H, OCH3); 4.18 (dd, 1 H,
H(9), J = 18.4 Hz, J = 12.0 Hz); 5.35 (dd, 1 H, H(10), J = 6.9 Hz,
J = 12.0); 6.81 (m, 1 H, H(18)); 6.87—6.93 (m, 4 H, H(11), H(12),
H(14), H(15)); 7.24—7.30 (m, 4 H, H(16), H(17), H(19), H(20));
7.41 (m, 2 H, H(6), H(8)); 7.69 (m, 1 H, H(7)); 7.99 (d, 1 H, H(5),
J = 6.8 Hz); 14.10 (s, 1 H, OH). MS, m/z (Irel (%)): 412 (95).
Found (%): C, 72.69; H, 4.93; N, 6.22. C25H20N2O4. Calculatꢀ
ed (%): C, 72.82; H, 4.85; N, 6.10.
3ꢀ{(E)ꢀ3ꢀ[4ꢀ(Dimethylamino)phenyl]propꢀ2ꢀenoyl}ꢀ4ꢀhydrꢀ
oxycoumarin (2l). Yield 97%, m.p. 214—215 °C (cf. Ref. 20: m.p.
212—215 °C).
4ꢀHydroxyꢀ3ꢀ[5ꢀ(4ꢀmethoxyphenyl)ꢀ1ꢀ(4ꢀfluorophenyl)ꢀ4,5ꢀdiꢀ
hydroꢀ1Hꢀpyrazolꢀ3ꢀyl]coumarin (4b). Yield 78%, m.p. 204—206 °C.
1H NMR (DMSOꢀd6), δ: 3.38 (dd, 1 H, H(9), J = 18.9 Hz,
J = 8.7 Hz); 3.71 (s, 3 H, OCH3); 4.12 (dd, 1 H, H(9), J = 18.9 Hz,
J = 12.3 Hz); 5.30 (dd, 1 H, H(10), J = 8.7 Hz, J = 12.30 Hz);
6.54—7.45 (m, 10 H, H(6), H(8), H(11), H(12), H(14), H(15),
H(16), H(17), H(19), H(20)); 7.68 (m, 1 H, H(7)); 7.98 (d, 1 H,
H(5), J = 7.0 Hz); 10.31 (s, 0.45 H, NH); 13.88 (s, 0.55 H, OH).
MS, m/z (Irel (%)): 430 (80). Found (%): C, 69.18; H, 4.23;
N, 6.72. C25H19FN2O4. Calculated (%): C, 69.76; H, 4.45; N, 6.51.
4ꢀHydroxyꢀ3ꢀ[5ꢀ(4ꢀmethoxyphenyl)ꢀ1ꢀ(4ꢀtolyl)ꢀ4,5ꢀdihydroꢀ
1Hꢀpyrazolꢀ3ꢀyl]coumarin (4c). Yield 77%, m.p. 215—217 °C.
1H NMR (DMSOꢀd6), δ: 2.19 (s, 3 H, CH3); 3.35 (dd, 1 H, H(9),
J = 18.9 Hz, J = 8.2 Hz); 3.70 (s, 3 H, OCH3); 4.13 (dd, 1 H, H(9),
J = 18.9 Hz, J = 12.3 Hz); 5.36 (dd, 1 H, H(10), J = 8.0 Hz,
J = 12.3 Hz); 6.84—6.92 (m, 4 H, H(11), H(12), H(14), H(15));
7.06 (d, 2 H, H(17), H(19), J = 8.3 Hz); 7.27 (d, 2 H, H(16),
H(20), J = 8.3 Hz); 7.44 (m, 2 H, H(6), H(8)); 7.69 (m, 1 H,
H(7)); 7.98 (d, 1 H, H(5), J = 7.4 Hz); 14.05 (s, 1 H, OH). MS,
4ꢀHydroxyꢀ3ꢀ[(E)ꢀ3ꢀ(5ꢀpiperidinoꢀ2ꢀthienyl)propꢀ2ꢀenoyl]ꢀ
coumarin (2m). Yield 98%, m.p. 225—227 °C. 1H NMR (DMSOꢀd6),
δ: 1.73 (m, 6 H, H(14), H(15), H(16)); 3.58 (t, 4 H, H(13), H(17),
J = 9.4 Hz); 6.57 (d, 1 H, H(12), J = 5.5 Hz); 7.36 (m, 3 H, H(6),
H(8), H(11)); 7.70 (m, 2 H, H(7), H(10)); 7.98 (d, 1 H, H(5),
J = 7.9 Hz); 8.22 (d, 1 H, H(9), J = 14.3 Hz); 18.65 (s, 1 H, OH).
MS, m/z (Irel (%)): 381 (75). Found (%): C, 66.02; H, 5.07;
N, 3.79. C21H19NO4S. Calculated (%): C, 66.14; H, 4.99; N, 3.67.
4ꢀHydroxyꢀ3ꢀ[(E)ꢀ3ꢀ(5ꢀmorpholinoꢀ2ꢀthienyl)propꢀ2ꢀenoyl]ꢀ
coumarin (2n). Yield 91%, m.p. 284—286 °C. 1H NMR (DMSOꢀd6),
δ: 3.63 (m, 8 H, H(13), H(14), H(15), H(16)); 6.49 (d, 1 H, H(12),
J = 4.6 Hz); 7.36 (m, 3 H, H(6), H(8), H(10)); 7.73 (m, 2 H, H(7),
H(11)); 7.97 (d, 1 H, H(5), J = 6.9 Hz); 8.23 (d, 1 H, H(9),
J = 14.8 Hz); 17.81 (s, 1 H, OH). MS, m/z (Irel (%)): 383 (95).
Found (%): C, 62.88; H, 4.28; N, 3.79. C20H17NO5S. Calculatꢀ
ed (%): C, 62.66; H, 4.44; N, 3.66.

1514
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 7, July, 2008
Traven et al.
m/z (Irel (%)): 426 (85). Found (%): C, 73.68; H, 5.43; N, 6.39.
C26H22N2O4. Calculated (%): C, 73.23; H, 5.20; N, 6.57.
4ꢀHydroxyꢀ3ꢀ[1,5ꢀdi(4ꢀmethoxyphenyl)ꢀ4,5ꢀdihydroꢀ1Hꢀ
pyrazolꢀ3ꢀyl]coumarin (4d). Yield 79%, m.p. 199—201 °C. 1H NMR
(DMSOꢀd6), δ: 3.37 (dd, 1 H, H(9), J = 18.9 Hz, J = 9.7 Hz);
3.68, 3.72 (both s, 3 H each, OCH3); 4.13 (dd, 1 H, H(9), J = 18.9 Hz,
J = 11.7 Hz); 5.21 (dd, 1 H, H(10), J = 9.7 Hz, J = 11.78 Hz); 6.86
(m, 6 H, H(11), H(12), H(14), H(15), H(17), H(19)); 7.38 (m, 4 H,
H(6), H(8), H(16), H(20)); 7.69 (m, 1 H, H(7)); 7.98 (d, 1 H,
H(5), J = 8.2 Hz); 13.86 (s, 1 H, OH). MS, m/z (Irel (%)): 442 (95).
Found (%): C, 71.01; H, 5.13; N, 6.18. C26H22N2O5. Calculatꢀ
ed (%): C, 70.58; H, 5.01; N, 6.33.
4ꢀHydroxyꢀ3ꢀ[5ꢀ(4ꢀmethoxyphenyl)ꢀ1ꢀ(4ꢀnitrophenyl)ꢀ4,5ꢀ
dihydroꢀ1Hꢀpyrazolꢀ3ꢀyl]coumarin (4e). Yield 72%, m.p. 261—263 °C.
1H NMR (DMSOꢀd6), δ: 3.43 (dd, 1 H, H(9), J = 19.4 Hz,
J = 6.1 Hz); 3.63 (s, 3 H, OCH3); 4.18 (dd, 1 H, H(9), J = 19.4 Hz,
J = 11.7 Hz); 5.15 (dd, 1 H, H(10), J = 6.1 Hz, J = 11.7 Hz);
6.94—7.26 (m, 6 H, H(11), H(12), H(14), H(15), H(16), H(20));
7.48 (m, 2 H, H(6), H(8)); 7.71 (m, 1 H, H(7)); 8.08—8.14
(m, 3 H, H(5), H(17), H(19)); 13.82 (s, 1 H, OH). MS, m/z
(Irel (%)): 457 (90). Found (%): C, 65.32; H, 4.29; N, 9.31.
C25H19N3O6. Calculated (%): C, 65.64; H, 4.19; N, 9.19.
3ꢀ[5ꢀ(2,4ꢀDimethoxyphenyl)ꢀ1ꢀphenylꢀ4,5ꢀdihydroꢀ1Hꢀpyrꢀ
azolꢀ3ꢀyl]ꢀ4ꢀhydroxycoumarin (4f). Yield 61%, m.p. 202—203 °C
(cf. Ref. 15: m.p. 218 °C). 1H NMR (DMSOꢀd6), δ: 3.30 (dd, 1 H,
H(9), J = 18.8 Hz, J = 6.7 Hz); 3.75, 3.90 (both s, 3 H each,
OCH3); 4.15 (dd, 1 H, H(9), J = 18.8 Hz, J = 12.4 Hz); 5.40
(dd, 1 H, H(10), J = 6.7 Hz, J = 12.4 Hz); 6.30 (d, 1 H, H(12),
J = 7.8 Hz); 6.52 (s, 1 H, H(14)); 6.80 (m, 3 H, H(16), H(17),
H(19)); 6.90 (d, 1 H, H(11), J = 7.8 Hz); 7.16 (m, 2 H, H(16),
H(20)); 7.30 (m, 2 H, H(6), H(8)); 7.60 (m, 1 H, H(7)); 7.94 (d, 1 H,
H(5), J = 6.8 Hz); 13.95 (s, 1 H, OH). MS, m/z (Irel (%)): 442 (90).
Found (%): C, 70.52; H, 5.06; N, 6.28. C26H22N2O5. Calculatꢀ
ed (%): C, 70.58; H, 5.01; N, 6.33.
3ꢀ[5ꢀ(2,4ꢀDimethoxyphenyl)ꢀ1ꢀ(4ꢀfluorophenyl)ꢀ4,5ꢀdihydroꢀ
1Hꢀpyrazolꢀ3ꢀyl]ꢀ4ꢀhydroxycoumarin (4g). Yield 74%, m.p.
>350 °C. 1H NMR (DMSOꢀd6), δ: 3.63 (dd, 1 H, H(9), J = 18.4 Hz,
J = 12.4 Hz); 3.74, 3.85 (both s, 3 H each, OCH3); 4.07 (dd, 1 H,
H(9), J = 18.4 Hz, J = 6.4 Hz); 5.45 (dd, 1 H, H(10), J = 6.4 Hz,
J = 12.4 Hz); 6.46 (d, 1 H, H(12), J = 8.3 Hz); 6.63 (s, 1 H, H(14));
6.73—7.11 (m, 5 H, H(11), H(16), H(17), H(19), H(20)); 7.44
(m, 2 H, H(6), H(8)); 7.71 (m, 1 H, H(7)); 8.00 (d, 1 H, H(5),
J = 7.4 Hz); 14.18 (s, 1 H, OH). MS, m/z (Irel (%)): 460 (73).
Found (%): C, 67.61; H, 4.73; N, 6.19. C26H21FN2O5. Calculatꢀ
ed (%): C, 67.82; H, 4.60; N, 6.08.
H(10), J = 5.6 Hz, J = 11.8 Hz); 6.36 (d, 1 H, H(12), J = 8.2 Hz);
6.50 (s, 1 H, H(14)); 6.84 (d, 2 H, H(16), H(20), J = 9.0 Hz);
7.35—7.44 (m, 3 H, H(6), H(8), H(11)); 7.57 (m, 1 H, H(7));
8.06—8.15 (m, 3 H, H(5), H(17), H(19)); 13.60 (s, 1 H, OH).
MS, m/z (Irel (%)): 487 (80). Found (%): C, 64.24; H, 4.18;
N, 8.53. C26H21N3O7. Calculated (%): C, 64.06; H, 4.34; N, 8.62.
3ꢀ{5ꢀ[4ꢀ(N,NꢀDimethylamino)phenyl]ꢀ1ꢀphenylꢀ4,5ꢀdihydroꢀ
1Hꢀpyrazolꢀ3ꢀyl}ꢀ4ꢀhydroxycoumarin (4j). Yield 54%, m.p.
229—231 °C. 1H NMR (DMSOꢀd6), δ: 2.93 (s, 6 H, (CH3)2); 3.57
(dd, 1 H, H(9), Jgem = 18.96 Hz, Jvic = 6.28 Hz); 4.19 (dd, 1 H,
H(9), Jgem = 18.96 Hz, Jvic = 12.30 Hz); 5.12 (dd, 1 H, H(10),
Jcis = 6.28 Hz, Jtrans = 12.30 Hz); 6.68 (d, 2 H, H(12), H(14),
J = 8.41 Hz); 6.85 (m, 1 H, H(18)); 6.96 (m, 2 H, H(17), H(19));
7.13—7.25 (m, 4 H, H(11), H(15), H(16), H(20)); 7.30 (m, 2 H,
H(6), H(8)); 7.56 (m, 1 H, H(7)); 8.02 (d, 1 H, H(5), J = 7.32 Hz);
14.11 (s, 1 H, OH). MS, m/z (Irel (%)): 425 (100). Found (%):
C, 73.38; H, 5.48; N, 9.82. C26H23N3O3. Calculated (%): C, 73.40;
H, 5.45; N, 9.88.
3ꢀ{5ꢀ[4ꢀ(N,NꢀDimethylamino)phenyl]ꢀ1ꢀ(4ꢀfluorophenyl)ꢀ4,5ꢀ
dihydroꢀ1Hꢀpyrazolꢀ3ꢀyl}ꢀ4ꢀhydroxycoumarin (4k). Yield 74%,
m.p. >350 °C. 1H NMR (DMSOꢀd6), δ: 2.54 (s, 6 H, 2 CH3); 3.03
(dd, 1 H, H(9), J = 18.9 Hz, J = 8.7 Hz); 4.05 (dd, 1 H, H(9),
J = 18.9 Hz, J = 12.3 Hz); 5.23 (dd, 1 H, H(10), J = 8.7 Hz,
J = 12.3 Hz); 6.68 (d, 2 H, H(12), H(14), J = 8.3 Hz); 6.84—7.06
(m, 6 H, H(11), H(15), H(16), H(17), H(19), H(20)); 7.42 (m, 2 H,
H(6), H(8)); 7.69 (m, 1 H, H(7)); 7,98 (d, 1 H, H(5), J = 6.4 Hz);
14.47 (s, 1 H, OH). MS, m/z (Irel (%)): 443 (65). Found (%):
C, 70.21; H, 5.09; N, 9.31. C26H22FN3O3. Calculated (%):
C, 70.42; H, 5.00; N, 9.48.
3ꢀ{5ꢀ[4ꢀ(N,NꢀDimethylamino)phenyl]ꢀ1ꢀ(4ꢀmethoxyphenyl)ꢀ
4,5ꢀdihydroꢀ1Hꢀpyrazolꢀ3ꢀyl}ꢀ4ꢀhydroxycoumarin (4l). Yield
1
77%, m.p. 175—177 °C. H NMR (DMSOꢀd6), δ: 2.91 (s, 6 H,
2 CH3); 3.35 (dd, 1 H, H(9), J = 18.9 Hz, J = 9.2 Hz); 3.62 (s, 3 H,
OCH3); 4.12 (dd, 1 H, H(9), J = 18.9 Hz, J = 11.7 Hz); 5.11
(dd, 1 H, H(10), J = 9.2 Hz, J = 11.7 Hz); 6.63—6.92 (m, 6 H,
H(11), H(12), H(14), H(15), H(17), H(19)); 7.17 (d, 2 H, H(16),
H(20), J = 9.3 Hz); 7.38 (m, 2 H, H(6), H(8)); 7.65 (m, 1 H,
H(7)); 7.96 (d, 1 H, H(5), J = 7.3 Hz); 14.06 (s, 1 H, OH). MS, m/z
(Irel (%)): 455 (65). Found (%): C, 71.40; H, 5.39; N, 9.12.
C27H25N3O4. Calculated (%): C, 71.19; H, 5.53; N, 9.22.
3ꢀ[5ꢀ(Benzothiazolꢀ2ꢀyl)ꢀ1ꢀ(4ꢀmethoxyphenyl)ꢀ4,5ꢀdihydroꢀ
1Hꢀpyrazolꢀ3ꢀyl]ꢀ4ꢀhydroxycoumarin (4m). Yield 79%, m.p.
241—243 °C. 1H NMR (DMSOꢀd6), δ: 3.47 (dd, 1 H, H(9),
J = 18.8 Hz, J = 12.4 Hz); 3.69 (s, 3 H, OCH3); 4.22 (dd, 1 H,
H(9), J = 18.8 Hz, J = 6.7 Hz); 5.69 (dd, 1 H, H(10), J = 6.7 Hz,
J = 12.4 Hz); 6.88 (d, 2 H, H(12), H(14), J = 8.3 Hz); 7.13
(m, 1 H, H(17)); 7.31 (m, 3 H, H(11), H(15), H(19)); 7.46 (m, 3 H,
H(6), H(8), H(18)); 7.76 (m, 1 H, H(7)); 7.82 (d, 1 H, H(16),
J = 7.8 Hz); 8.02 (d, 1 H, H(5), J = 7.8 Hz). MS, m/z (Irel (%)): 469
(70). Found (%): C, 66.21; H, 4.14; N, 8.69. C26H19N3O4S.
Calculated (%): C, 66.52; H, 4.05; N, 8.96.
3ꢀ[5ꢀ(Benzothiazolꢀ2ꢀyl)ꢀ1ꢀ(2,4ꢀdimethoxyphenyl)ꢀ4,5ꢀdihyꢀ
droꢀ1Hꢀpyrazolꢀ3ꢀyl]ꢀ4ꢀhydroxycoumarin (4n). Yield 74%, m.p.
225—227 °C. 1H NMR (DMSOꢀd6), δ: 3.39 (dd, 1 H, H(9),
J = 18.9 Hz, J = 12.4 Hz); 3.68, 3.82 (both s, 3 H each, OCH3);
4.11 (dd, 1 H, H(9), J = 18.9 Hz, J = 6.3 Hz); 5.71 (dd, 1 H, H(10),
J = 6.3 Hz, J = 12.4 Hz); 6.45 (d, 1 H, H(12), J = 8.2 Hz); 6.64
(s, 1 H, H(14)); 6.97 (d, 1 H, H(11), J = 8.2 Hz); 7.12 (m, 1 H,
H(17)); 7.25 (m, 1 H, H(18)); 7.43 (m, 3 H, H(6), H(8), H(19));
7.67 (m, 1 H, H(7)); 7.84 (d, 1 H, H(16), J = 7.9); 8.01 (d, 1 H,
H(5), J = 8.2 Hz). MS, m/z (Irel (%)): 487 (85). Found (%):
3ꢀ[5ꢀ(2,4ꢀDimethoxyphenyl)ꢀ1ꢀ(4ꢀtolyl)ꢀ4,5ꢀdihydroꢀ1Hꢀ
pyrazolꢀ3ꢀyl]ꢀ4ꢀhydroxycoumarin (4h). Yield 75%, m.p. >350 °C.
1H NMR (DMSOꢀd6), δ: 2.17 (s, 3 H, CH3); 3.39 (dd, 1 H, H(9),
J = 18.9 Hz, J = 7.7 Hz); 3.71, 3.78 (both s, 3 H each, OCH3);
4.09 (dd, 1 H, H(9), J = 18.9 Hz, J = 12.3 Hz); 5.46 (dd, 1 H,
H(10), J = 7.7 Hz, J = 12.3 Hz); 6.41 (d, 1 H, H(12), J = 8.5 Hz);
6.65 (s, 1 H, H(14)); 6.77 (d, 1 H, H(11), J = 8.5 Hz); 7.02—7.14
(m, 4 H, H(16), H(17), H(19), H(20)); 7.46 (m, 2 H, H(6), H(8));
7.71 (m, 1 H, H(7)); 8.01 (d, 1 H, H(5), J = 7.9 Hz); 14.27 (s, 1 H,
OH). MS, m/z (Irel (%)): 456 (75). Found (%): C, 71.22; H, 5.49;
N, 6.21. C27H24N2O5. Calculated (%): C, 71.04; H, 5.30; N, 6.14.
3ꢀ[5ꢀ(2,4ꢀDimethoxyphenyl)ꢀ1ꢀ(4ꢀnitrophenyl)ꢀ4,5ꢀdihydroꢀ
1Hꢀpyrazolꢀ3ꢀyl]ꢀ4ꢀhydroxycoumarin (4i). Yield 71%, m.p.
225—227 °C. 1H NMR (DMSOꢀd6), δ: 3.61 (dd, 1 H, H(9),
J = 19.48 Hz, J = 5.64 Hz); 3.75, 3.88 (both s, 3 H each, OCH3);
4.20 (dd, 1 H, H(9), J = 19.4 Hz, J = 11.8 Hz); 4.58 (dd, 1 H,

New 3ꢀpyrazolinylcoumarins and 2ꢀquinolones
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 7, July, 2008
1515
C, 64.33; H, 4.14; N, 8.49. C26H21N3O5S. Calculated (%):
C, 64.06; H, 4.31; N, 8.62.
(d, 2 H, H(18), H(20), J = 8.0 Hz); 7.05 (d, 2 H, H(17), H(21),
J = 8.0); 7.26—7.35 (m, 2 H, H(6), H(8)); 7.60 (m, 1 H, H(7));
8.18 (d, 1 H, H(5), J = 7.6 Hz); 13.72 (s, 1 H, OH). MS, m/z
(Irel (%)): 516 (85). Found (%): C, 65.21; H, 5.39; N, 10.77.
C28H28N4O4S. Calculated (%): C, 65.10; H, 5.46; N, 10.84.
Synthesis of 4ꢀhydroxyꢀ3ꢀpyrazolinylꢀ2ꢀquinolones 6. A. 3ꢀcinꢀ
namoylꢀ4ꢀhydroxyꢀ2ꢀquinolone 5a (0.5 g) was dissolved on heatꢀ
ing in acetic acid (30 mL), and a 3—4ꢀfold molar excess of phenylꢀ
hydrazine was added to the resulting solution. The mixture was
refluxed for 30 min. After cooling, the precipitate was filtered off and
recrystallized from alcohol.
This work was supported by the Russian Foundation
for Basic Research (Project No. 07ꢀ03ꢀ00936).
4ꢀHydroxyꢀ3ꢀ[5ꢀ(4ꢀmethoxyphenyl)ꢀ1ꢀphenylꢀ4,5ꢀdihydroꢀ
1Hꢀpyrazolꢀ3ꢀyl]ꢀ1ꢀmethylquinolinꢀ2ꢀ(1H)ꢀone (6a). Yield 87%,
m.p. 198—199 °C. 1H NMR (CDCl3), δ: 3.65 (m, 4 H, NMe,
H(9)); 3.72 (s, 3 H, OCH3); 4.27 (dd, 1 H, H(9), J = 18.5 Hz,
J = 12.0 Hz); 5.18 (dd, 1 H, H(10), J = 7.5 Hz, J = 12.0 Hz);
6.82—6.90 (m, 3 H, H(12), H(14), H(18)); 6.96 (m, 2 H, H(11),
H(15)); 7.20—7.36 (m, 6 H, H(6), H(8), H(16), H(17), H(20), H(21));
7.62 (m, 1 H, H(7)); 8.22 (d, 1 H, H(5), J = 7.9 Hz); 13.70 (s, 1 H,
OH). MS, m/z (Irel (%)): 425 (90). Found (%): C, 73.29; H, 5.34;
N, 9.94. C26H23N3O3. Calculated (%): C, 73.40; H, 5.45; N, 9.88.
B. A 3—4ꢀfold molar excess of phenylhydrazine hydrochloride
and KOH (0.3 g) were added at reflux to a suspension of
3ꢀcinnamoylꢀ4ꢀhydroxyꢀ2ꢀquinolone 5a,b (0.5 g) in isopropyl alꢀ
cohol (30 mL) and the mixture was refluxed for 1 h. After cooling,
the reaction mixture was filtered off. The resulting precipitate was
recrystallized from alcohol.
4ꢀHydroxyꢀ3ꢀ[5ꢀ(4ꢀmethoxyphenyl)ꢀ1ꢀ(4ꢀfluorophenyl)ꢀ4,5ꢀ
dihydroꢀ1Hꢀpyrazolꢀ3ꢀyl]ꢀ1ꢀmethylquinolinꢀ2(1H)ꢀone (6b). Yield
79%, m.p. 207—208 °C. 1H NMR (CDCl3), δ: 3.60 (m, 4 H, NMe,
H(9)); 3.78 (s, 3 H, OCH3); 4.23 (dd, 1 H, H(9), J = 18.7 Hz,
J = 12.1 Hz); 5.06 (dd, 1 H, H(10), J = 8.0 Hz, J = 12.1 Hz);
6.80—7.48 (m, 10 H, H(6), H(8), H(11), H(12), H(14), H(15),
H(16), H(17), H(19), H(20)); 7.48 (m, 1 H, H(7)); 8.20 (d, 1 H,
H(5), J = 8.0 Hz); 13.60 (s, 1 H, OH). MS, m/z (Irel (%)): 443 (85).
Found (%): C, 70.34; H, 4.92; N, 9.36. C26H22FN3O3. Calculatꢀ
ed (%): C, 70.42; H, 5.00; N, 9.48.
References
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3ꢀ[1,5ꢀBis(4ꢀmethoxyphenyl)ꢀ4,5ꢀdihydroꢀ1Hꢀpyrazolꢀ3ꢀyl]ꢀ
4ꢀhydroxyꢀ1ꢀmethylquinolinꢀ2(1H)ꢀone (6c). Yield 74%, m.p.
176—177 °C. 1H NMR (CDCl3)б δ: 3.52 (m, 4 H, NMe, H(9));
3.70 (m, 6 H, OCH3); 4.30 (dd, 1 H, H(9), J = 18.4 Hz, J = 12.0 Hz);
5.06 (dd, 1 H, H(10), J = 8.6 Hz, J = 11.6 Hz); 6.70—7.06 (m, 10 H,
H(6),H(8),H(11),H(12),H(14),H(15),H(16),H(17),H(19),H(20));
7.62 (m, 1 H, H(7)); 8.14 (d, 1 H, H(5), J = 8.2 Hz); 13.70 (s, 1 H,
OH). MS, m/z (Irel (%)): 455 (90). Found (%): C, 71.08; H, 5.47;
N, 9.20. C27H25N3O4. Calculated (%): C, 71.19; H, 5.53; N, 9.22.
{1ꢀ(4ꢀFluorophenyl)ꢀ3ꢀ[5ꢀ(5ꢀmorpholinoꢀ2ꢀthienyl)]ꢀ4,5ꢀdiꢀ
hydroꢀ1Hꢀpyrazolꢀ3ꢀyl}ꢀ4ꢀhydroxyꢀ1ꢀmethylquinolinꢀ2(1H)ꢀone
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1
(6d). Yield 85%, m.p. 190—191 °C. H NMR (CDCl3), δ: 3.02
(m, 4 H, H(14), H(15)); 3.60 (s, 3 H, NMe, H(9)); 3.70—3.86 (m, 5 H,
H(9), H(13), H(16)); 4.15 (dd, 1 H, H(9), J = 18.0 Hz, J = 11.8 Hz);
5.08 (dd, 1 H, H(10), J = 8.2 Hz, J = 12.0 Hz); 5.95 (d, 1 H, H(12),
J = 3.1 Hz); 6.70 (d, 1 H, H(11), J = 3.1 Hz); 6.82 (m, 4 H, H(17),
H(18), H(20), H(21)); 7.25—7.32 (m, 2 H, H(6), H(8)); 7.60
(m, 1 H, H(7)); 8.15 (d, 1 H, H(5), J = 8.0 Hz); 13.55 (s, 1 H, OH). MS,
m/z (Irel (%)): 504 (95). Found (%): C, 64.15; H, 5.02; N, 11.19.
C27H25FN4O3S. Calculated (%): C, 64.27; H, 4.99; N, 11.10.
4ꢀHydroxyꢀ3ꢀ[1ꢀ(4ꢀmethoxyphenyl)ꢀ5ꢀ(5ꢀmorpholinoꢀ2ꢀ
thienyl)ꢀ4,5ꢀdihydroꢀ1Hꢀpyrazolꢀ3ꢀyl]ꢀ1ꢀmethylquinolinꢀ2(1H)ꢀ
one (6e). Yield 82%, m.p. 186—187 °C. 1H NMR (CDCl3), δ: 3.10
(m, 4 H, H(14), H(15)); 3.62 (s, 3 H, NMe); 3.72—3.90 (m, 8 H,
OMe, H(9), H(13), H(16)); 4.20 (dd, 1 H, H(9), J = 17.8 Hz,
J = 11.6 Hz); 5.12 (dd, 1 H, H(10), J = 8.3 Hz, J = 11.8 Hz); 5.95
(d, 1 H, H(12), J = 2.8 Hz); 6.70 (d, 1 H, H(11), J = 2.8 Hz); 6.82
20. A. V. Manaev, T. A. Chibisova, V. F. Traven, Izv. Akad. Nauk.
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Chem. Bull., Int. Ed., 2006, 55, 2091].
22. A. V. Manaev, I. N. Okhrimenko, K. A. Lysenko, V. F. Traven,
Izv. Akad. Nauk. Ser. Khim., 2008, 1701 [Russ. Chem. Bull., Int.
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Received April 1, 2008;
in revised form May 23, 2008