Polyfused nitrogen-containing heterocycles 23.* Methyl 4-hydroxy-3-phenyl-5-phenyl(alkyl)-2-phenyliminoselenazolidine-4-carboxylates and selenazolo[3,4-a]quinoxalin-4(5H)-one derivatives on their basis

Article abstract of DOI:10.1007/s11172-009-0170-8

Condensation of methyl phenyl(alkyl)halopyrotartrates with N, N'-diphenylselenourea leads to the formation of methyl 4-hydroxy-3-phenyl-5- phenyl(alkyl)-2-phenyliminoselenazolidine-4-carboxylates, which undergo reaction with 1,2-phenylenediamines to give selenazolo-[3,4-a]quinoxalin-4(5H)-ones. ; 2009 Springer Science+Business Media, Inc.

Full text of DOI:10.1007/s11172-009-0170-8

Russian Chemical Bulletin, International Edition, Vol. 58, No. 6, pp. 1294—1302, June, 2009
1294
Polyfused nitrogenꢀcontaining heterocycles
23.* Methyl 4ꢀhydroxyꢀ3ꢀphenylꢀ5ꢀphenyl(alkyl)ꢀ
2ꢀphenyliminoselenazolidineꢀ4ꢀcarboxylates
and selenazolo[3,4ꢀa]quinoxalinꢀ4(5H)ꢀone derivatives on their basis**
V. A. Mamedov, N. A. Zhukova, A. T. Gubaidullin, T. N. Beschastnova,
I. Kh. Rizvanov, Ya. A. Levin, and I. A. Litvinov
A. E. Arbuzov Institute of Organic and Physical Chemistry,
Kazan Research Center of the Russian Academy of Sciences,
8 ul. Akad. Arbuzova, 420088 Kazan, Russian Federation.
Fax: +7 (843) 273 2253. Eꢀmail: mamedov@iopc.knc.ru
Condensation of methyl phenyl(alkyl)halopyrotartrates with N,N´ꢀdiphenylselenourea leads
to the formation of methyl 4ꢀhydroxyꢀ3ꢀphenylꢀ5ꢀphenyl(alkyl)ꢀ2ꢀphenyliminoselenazolidineꢀ
4ꢀcarboxylates, which undergo reaction with 1,2ꢀphenylenediamines to give selenazoloꢀ
[3,4ꢀa]quinoxalinꢀ4(5H)ꢀones.
Key words: N,N´ꢀdiphenylselenourea, phenylꢀ and alkylhalopyruvates, methyl 4ꢀhydroxyꢀ
3ꢀphenylꢀ5ꢀphenyl(alkyl)ꢀ2ꢀphenyliminoselenazolidineꢀ4ꢀcarboxylates, selenazolo[3,4ꢀa]quiꢀ
noxalinꢀ4(5H)ꢀones, IR spectroscopy, NMR spectroscopy, Xꢀray diffraction.
During the last thirty years, organoselenium comꢀ
pounds are under intensive study in the field of synthetic
organic chemistry and pharmacology, which is due to
their high reactivity2—8 and wide range of biological and
pharmacological activity,2,8—11 including antiviral,2,9,10
antibacterial,2,9,10 antifungus,2,9 antioxidant,9,10 antiꢀ
prolifiration,12,13 and antitumor.9,14—16 Derivatives of
1,3ꢀselenazolidine 1 are of special interest among seleꢀ
niumꢀcontaining organic compounds,16—19 the study of
pharmaceutical potential of which showed a possibility to
use these compounds as inhibitors of NOꢀsynthase,20,21
antimutagenes,22 and cancer preventing agents.23—26
From the point of view of developing methods for the
synthesis and study of pharmacological activity, the most
prospective are selenazolidines corresponding to the strucꢀ
ture 1. For the most of them, a common feature is the
presence of exocyclic double bond C=O, C=N, or C=C
at the second position. The presence of other substituents
in 1,3ꢀselenazolidines 1 makes their synthesis and the
search for new pharmacologically useful compounds more
difficult.
X = C(CN)CO2Et, O, NH;
R = H, Alk, Ar;
R´ = H, Alk, CO2H;
R″ = H, Alk
2ꢀphenyliminothiazolidineꢀ4ꢀcarboxylate (2),27—30 as well
as its aryl and hetaryl analogs.29,31 However, synthetic
possibilities of this reaction remain still little studied.29—31
Scheme 1
Earlier, we have suggested (Scheme 1) a method for
the synthesis of various thiazolo[3,4ꢀa]quinoxalines 4 from
1,2ꢀphenylenediamines 3 and structurally related to
selenazolidines
1 methyl 4ꢀhydroxyꢀ3,5ꢀdiphenylꢀ
* For Part 22, see Ref. 1
** Dedicated to Academician O. N. Chupakhin on the occasion
of his 75th birthday.
R = R´ = H (a); R = H, R´ = Me (b); R = H, R´ = NO2 (c)
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1258—1265, June, 2009.
1066ꢀ5285/09/5806ꢀ1294 © 2009 Springer Science+Business Media, Inc.

Selenazolo[3,4ꢀa]quinoxalynꢀ4(5H)ꢀones
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1295
The present work is devoted to the synthesis (Scheme 2)
and structural study of selenium analogs of methyl
4ꢀhydroxythiazolidineꢀ4ꢀcarboxylate 2, viz., 4ꢀhydroxyꢀ
selenazolidineꢀ4ꢀcarboxylic esters 7, as well as possibility
of their use in the synthesis of selenazolo[3,4ꢀa]quinoxꢀ
alines according to Scheme 1.
It should be noted that, as in the case of ester 2 studied
by us earlier,33 the 1H NMR spectrum of ester 7a in soluꢀ
tion recorded right after dissolution exhibits only one pair
of singlet signals for the methylene and methoxy groups
(δ 5.58 and 3.57, respectively), whereas after one day,
another pair of signals (δ 5.13 and 3.13) appears. In the
1H NMR spectra of solutions of compounds 7b,c, similar
complication with time are also observed (Table 1). Going
from ester 2 to its selenium analog 7a, chemical shifts
for the methoxy protons are displaced upfield, whereas
for the methyne protons, downfield (see Table 1). In
Scheme 2
1
addition, in the H NMR spectrum of selenazolidine 7a
solution preliminary heated for 10 min at ~100 °C, the
third pair of singlet signals for the protons of the methylene
and methoxy groups appears at δ 6.42 and 3.80, respecꢀ
tively, in contrast to the spectrum of the sample of
thiazolidine 2 prepared similarly, in which the number
of diastereomers remains equal to two. This is apparently
due to the arising the openꢀchain tautomer 9a. From the
experimental data presented in Table 1, it is also seen that
the signals for the methyne protons of esters 7b,c are
shifted upfield as compared to such signals of ester 7a.
The IR spectra of esters 7 are characterized by the
presence of broad absorption bands at 3514 (7a), 3485
(7b), and 3489 cm–1 (7c), which can be related to the
vibrations νO—H of the bound hydroxy groups.
Condensation of 4ꢀhydroxyselenazolidineꢀ4ꢀcarboxyꢀ
lic esters 7a—c with 1,2ꢀphenylenediamine (3a) in boilꢀ
ing acetic acid gives the corresponding selenazolo[3,4ꢀa]ꢀ
quinoxalines 10a—c, the yields of which, in contrast to
the reaction of ester 2 with 1,2ꢀphenylenediamine (3a)
(~100%),29 do not exceed 9, 54, and 30%, respectively
(Scheme 4).
5, 7: R = Ph, X = Cl (a); R = Ph(CH2)2, X = Cl (b);
R = C6H13, X = Br (c)
Condensation of methyl phenyl(chloro)ꢀ (5a), phenylꢀ
ethyl(chloro)ꢀ (5b), and nꢀhexyl(bromo)pyrotartrates (5c)
with N,N´ꢀdiphenylselenourea (6)32 proceeds with the forꢀ
mation of products, which in their elemental composition
correspond to the expected isomeric methyl 4ꢀhydroxyꢀ
selenazolidineꢀ4ꢀcarboxylates 7a—c (see Scheme 2).
Similarly to the methyl ester 2 obtained by us earlier,33
esters 7a—c exist in solution (Scheme 3) in form of two
cyclic diastereomers, αꢀ7a—c and βꢀ7a—c, the equilibꢀ
rium between which, obviously, is established through the
openꢀchain isothioureide structure 9a—c.
Characteristics of the IR and NMR spectra of selenꢀ
azoloquinoxalines 10a—c are virtually identical to the
Scheme 4
Scheme 3
R = Ph, Z = S (2, 8); R = Ph, Z = Se (7a, 9a);
R = Ph(CH2)2, Z = Se (7b, 9b); R = C6H13, Z = Se (7c, 9c)
7, 10: R = Ph (a), Ph(CH2)2 (b), C6H13 (c)

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Mamedov et al.
Table 1. The change in the ratio of isomersa of methyl 4ꢀhydroxythiazolidineꢀ4ꢀcarboxylate 2
and methyl 4ꢀhydroxyselenazolidineꢀ4ꢀcarboxylates 7a—c in solution of DMSOꢀd6 at room
temperature depending on time (the 1H NMR data)
Object
Isomer
δ
Irel (%)
2 h
OMe
CH(R)
3 min
24 h
10 minb
αꢀ2 + 8 + βꢀ2c
1
2
1
2
3
1
2
1
2
3.16
3.60
3.13
3.57
3.80
3.59
3.85
3.66
3.89
5.05
5.46
5.13
5.58
6.42
0
100
0
100
—
100
0
100
0
19
81
8
92
—
86
14
63
37
33
67
18
82
—
—
—
—
—
—
—
14
41
45
—
—
—
—
αꢀ7a + 9a + βꢀ7a
αꢀ7b + 9b + βꢀ7b
αꢀ7c + 9c + βꢀ7c
4.37—4.41
4.22—4.25
4.43—4.49
4.33—4.37
a Calculated by averaging relative integral intensities of the methoxy and methyne protons.
b After heating the sample for 10 min at 100 °C.
c See Ref. 33.
corresponding characteristics of their thio analogs,
excluding a small difference in chemical shifts of diagꢀ
nostical signals for the proton H(9) and the proton of the
carbamoyl group, which, in the case of selenium derivaꢀ
tives resonate more downfield (by 0.04—0.09 ppm).
The reaction of 4ꢀhydroxyselenazolidineꢀ4ꢀcarboxyꢀ
lic ester 7b with 4,5ꢀdimethylꢀ1,2ꢀphenylenediamine (3d)
in boiling AcOH proceeds with the formation of expected
tricyclic compound 11 (Scheme 5), and for the reaction
to be completed, in this case it is necessary to reflux the
reaction mixture for 1 h, in contrast to the reaction
of ester 7b with 1,2ꢀphenylenediamine (3a) leading to
tricycle 10b over 1 min.
phenylenediamine (3b) a mixture of regioisomers 12a and
13a is formed (see Scheme 6), which is confirmed by the
doubling of all the signals in the 1H NMR spectrum of the
crude product. The integral intensity of the diagnostical
doublet signal for the proton H(9) (δ 9.17, J = 8.4 Hz) of
compound 2a is 2 times higher than the integral intensity
of the singlet signal for the proton H(9) (δ 9.15) of comꢀ
pound 13a.
Scheme 6
Scheme 5
R = Me (a), NO2 (b)
In contrast to 4ꢀmethylꢀ1,2ꢀphenylenediamine (3b),
the reaction of 4ꢀnitroꢀ1,2ꢀphenylenediamine (3c) with
ester 7b proceeds regioselectively to form only one out of
two possible isomeric selenazolo[3,4ꢀa]quinoxalines, to
which, with allowance for the predominant influence of
pꢀamino group on the reactivity, the structure 13b was
The use of 4ꢀsubstituted 1,2ꢀphenylenediamines 3b,c
in the reaction with ester 7b suggests a possibility to form
two isomeric selenazolo[3,4ꢀa]quinoxalines 12 and 13 difꢀ
fering in substituents at positions 7 and 8 (Scheme 6). In
fact, during condensation of ester 7b with 4ꢀmethylꢀ1,2ꢀ

Selenazolo[3,4ꢀa]quinoxalynꢀ4(5H)ꢀones
Russ.Chem.Bull., Int.Ed., Vol. 58, No. 6, June, 2009
1297
1
assigned (see Scheme 6). In fact, in the H NMR specꢀ
intermolecular interactions in the crystal of selenazoloꢀ
[3,4ꢀa]quinoxaline 13b there is observed characteristic
blockage by the present solvate DMF molecule of the
formation of Hꢀdimers of the molecules due to the interꢀ
eactions involving the carbamoyl groups. In the crystal,
the oxygen atom of the DMF molecule is involved into
the hydrogen bond with the N—H group of the tricyclic
fragment (parameters of the bond: d(H(5)...O(40)),
1.91(3) Å; d(N(5)...O(40)), 2.751(3) Å; the angle
N(5)—H(5)...O(40), 171(3)°), whereas the carbonyl
group of the molecule 13b is involved into the hydrogen
bond of the type C—H...O with the hydrogen atom of
the methyl group of the neighboring DMF molecule
(d(O(4)...H(42A´)), 2.36 Å; d(O(4)...C(42´)), 3.252(6)
Å; the angle O(4)...H(42A´)—C(42´), 155° (the symmetry
operation 1/2 – x, 1/2 + y, 1/2 – z)).
From the intramolecular interactions having certain
stabilizing influence on the conformation of the molꢀ
ecule, the hydrogen bonds involving the following atoms
as acceptors should be mentioned: the oxygen atom of the
carbonyl group (d(H(30A)...O(4)), 2.25 Å; d(C(30)...O(4)),
2.822(4) Å; the angle C(30)—H(30A)...O(4), 117°), the
imine atom N(11) (d(H(9)...N(11)), 2.17 Å; d(C(9)...N(11)),
2.806(3) Å; the angle C(9)—H(9)...N(11), 125°), and the
selenium atom (d(H(31B)...Se(2)), 2.87 Å; d(C(31)...Se(2)),
3.197(4) Å; the angle C(31)—H(31B)...Se(2), 101°). The
interactions of the π—π type in the crystal have been
analyzed using formal criteria of the presence of the π—π
interaction.37,38 In the crystal of compound 13b, there is
observed a stackingꢀeffect: the electronic systems of the
tricyclic fragments of the molecules, bound with the startꢀ
ing center of symmetry and translation along the 0b axis,
interact with each other by the headꢀtoꢀtail type so that
trum of the crude reaction product, along with other sigꢀ
nals, there is a diagnostical signal for the proton H(9) at
δ 10.35 in the form of a doublet with J = 2.6 Hz. This fact
indicates that the nitro group is on the atom C(8), rather
than on C(7), since in this case the diagnostical signal for
the proton H(9) would have resonate as a doublet of douꢀ
blets with J ≈ 8.5 and J ≈ 2.5 Hz.28,34 In contrast to the
reactions given above, the condensation of ester 7b with
4ꢀnitroꢀ1,2ꢀphenylenediamine (3c) proceeds slower and
to be completed requires reflux of the reaction mixture for
4 h, which is due to the strong electronꢀwithdrawing power
of the nitro group decreasing the reactivity of 1,2ꢀpheꢀ
nylenediamine 3c. The structure of selenazolo[3,4ꢀa]quiꢀ
noxaline 13b formed was confirmed by Xꢀray diffraction
analysis (Fig. 1). The molecule of 13b crystallizes with the
DMF molecule in the ratio 1 : 1.
The selenazolo[3,4ꢀa]quinoxaline fragment of the
molecule is planar within experimental error (0.095(1) Å)
(the value corresponds to the maximum deviation of one
of the atoms, in this case, of the selenium atom, from the
meanꢀsquare plane of the tricycle), with the nitro group
of the molecule being also in the plane of the tricyclic
fragment. The dihedral angles between the planes of the
phenyl substituents C(11)—C(16) and C(32)—C(37) and
the plane of the tricyclic system are 64.3(1) and 70.3(1)°,
respectively.
Similarly to the fact observed by us earlier31,33,35,36
in the crystals of pyrroloꢀ and azoloquinoxalines, for the
O(40)
C(40)
C(41)
N(40)
C(42)
C(15)
C(16)
C(13)
C(11)
N(11)
O(82)
O(81)
C(1)
Se(2)
C(3)
N(8)
C(9A)
N(10)
C(31)
C(8)
C(37)
C(30)
C(33)
C(7)
C(3A)
C(5A)
C(4)
C(6)
N(5)
C(35)
O(4)
Fig. 1. Molecular geometry of 13b in crystal. Nonhydrogen
atoms are given as probability ellipsoids of thermal vibrations
(p = 30%), hydrogen atoms as spheres of arbitrary radii. Some
bond distances in the tricyclic fragment/Å: Se(2)—C(1), 1.914(2);
Se(2)—C(3), 1.882(3); C(3)—C(3a), 1.333(4); C(3a)—C(4),
1.479(4); C(4)—N(5), 1.341(4); N(5)—C(5a), 1.366(4);
C(3a)—N(10), 1.419(3); C(1)—N(10), 1.399(3); C(1)—N(11),
1.266(3); C(9a)—N(10), 1.423(3).
Fig. 2. A fragment of an inclined stack of selenazolo[3,4ꢀa]ꢀ
quinoxaline 13b molecules in crystal. The DMF solvate molꢀ
ecules and hydrogen atoms are not shown.

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Mamedov et al.
Fig. 3. Formation of pseudochannels with the DMF molecules in the crystal of compound 13b. The view is along the 0b axis, the DMF
molecules are shown as large spheres.
Scheme 7
the fiveꢀmembered heterocycle of one of the molecule is
flanked from both sides by the fused benzene fragments
of the neighboring molecules (Fig. 2).
aline molecules, are associated with each other by the
van der Waals contacts, which leads to the formation
of pseudochannels in the crystal filled with the solvate
molecules (Fig. 3).
As a result, the inclined stacks of the molecules are
formed along the 0b crystallographic axis with the two
alternating distances between the meanꢀsquare planes of
the molecules (3.47 and 3.70 Å) in the stacks, the diheꢀ
dral angle between the planes is 0°. More close contact
of the molecules, apparently, is prevented by position of
the phenyl substituent on the imine nitrogen atom. The
inconvenience of mutual packing of bulky substituents
also explains the low value of calculated coefficient of
molecule packing, 67.7%. The DMF molecules, being
placed between the stacks of the selenazolo[3,4ꢀa]quinoxꢀ
To understand the reasons for the low yields of
selenazolo[3,4ꢀa]quinoxalines, the composition of the
reaction mixture from the reaction of ester 7c with
1,2ꢀphenylenediamine (3a) has been thoroughly analyzed.
It was found that, in addition to the desired product,
tricycle 10c, selenium is formed (the mass spectrum is
identical to the mass spectrum of the Se8 allotrope of
molecular selenium given in the NIST 98 library)39 and
N,N´ꢀdiphenylurea 14 (Scheme 7). This is evidence of
gradual decomposition of selenazolidine 7c, probably,

Selenazolo[3,4ꢀa]quinoxalynꢀ4(5H)ꢀones
Russ.Chem.Bull., Int.Ed., Vol. 58, No. 6, June, 2009
1299
poured to a suspension of N,N´ꢀdiphenylselenourea 6 (5 g,
18.2 mmol) in CH2Cl2 (150 mL), followed by a dropwise addition
of a solution of methyl chlorophenylpyrotartrate (5a) (3.9 g,
18.2 mmol) in CH2Cl2 (40 mL). The reaction mixture was stirred
for 9 h at room temperature, refluxed for 1 h, and cooled to
room temperatures. A precipitate was filtered off and the filtrate
was poured into water. The organic layer was separated, the
aqueous layer was extracted with CHCl3 (2×20 mL). The organic
layer and the extracts were combined, dried with MgSO4, the
solvent was evaporated, and the residue was recrystallized from
PriOH to obtain compound 7a (7 g, 72%), m.p. 143—148 °C.
Found (%): C, 61.45; H, 4.02; N, 6.19. C23H20N2O3Se. Calcuꢀ
lated (%): C, 61.20; H, 4.47; N, 6.21. IR, ν/cm–1: 3514 (OH),
3065—2853, 1740 (C=O), 1648, 1589. 1H NMR, δ: 3.13, 3.57
(both s, 3 H each, OCH3); 5.13, 5.58 (both s, 1 H each, CH);
6.84—7.46 (m, 2Ѕ16 H, 2Ѕ3 C6H5 + 2 OH). MS, m/z (Irel (%)):
454 (6), 453 (10), 452 (30), 451 (10), 450 (16), 449 (9), 448 (6)
([M]•+), 393 (10), 391 (5), 274 (6), 273 (6), 211 (9), 210 (62),
196 (19), 195 (91), 194 (100), 182 (9), 180 (14), 179 (8),
171 (15), 170 (14), 169 (19), 168 (14), 167 (29), 166 (8), 165 (7),
149 (16), 147 (5), 137 (16), 136 (18), 135 (9), 132 (10), 123 (16),
122 (6), 121 (28), 120 (11), 119 (14), 118 (26), 117 (8), 109 (15),
107 (13), 105 (9), 104 (12), 103 (8), 95 (25), 94 (7), 93 (21),
92 (29), 91 (55), 90 (23), 89 (14), 82 (12), 81 (60), 79 (11),
78 (9), 77 (72).
Methyl 4ꢀhydroxyꢀ3ꢀphenylꢀ5ꢀ(2ꢀphenylethyl)ꢀ2ꢀphenylꢀ
iminoselenazolidineꢀ4ꢀcarboxylate (7b) was obtained similarly to
ester 7a from methyl 3ꢀchloroꢀ2ꢀoxoꢀ5ꢀphenylpentanoate (5b)
(3.1 g, 12.9 mmol). The reaction mixture was poured into water.
The organic layer was separated, the aqueous layer was extracted
with CHCl3 (2×20 mL). The organic layer and the extracts
were combined, dried with MgSO4. The solvent was evaporated
in vacuo of a waterꢀjet pump, the residue was triturated with
PriOH, the crystals were filtered off. The filtrate was conꢀ
centrated to obtain compound 7b (4.2 g, 75%) (orange oil).
Found (%): C, 62.94; H, 5.02; N, 5.81. C25H24N2O3Se. Calcuꢀ
lated (%): C, 62.63; H, 5.05; N, 5.84. IR, ν/cm–1: 3485 (OH),
3176—2854, 1741 (C=O), 1632, 1588. 1H NMR (CDCl3), δ:
2.04—2.13, 2.26—2.36 (both m, 2 H each, 2 PhCH2CH2);
2.51—2.58, 2.66—2.75 (both m, 2 H each, 2 PhCH2CH2); 3.59,
3.85 (both s, 3 H each, OCH3); 4.22—4.25 (m, Хꢀpart of
ABXꢀsystem, 1 H, CH, JA,X + JB,X = 14.4 Hz); 4.37—4.41
(m, Хꢀpart of ABXꢀsystem, 1 H, CH, JA,X + JB,X = 14.7 Hz);
6.92—7.43 (m, 2×16 H, 2×3 C6H5 + 2 OH).
through the openꢀchain form under the action of water
liberating during the reaction (pathway A) and acetic acid
used as the solvent for the reaction (pathway B).
Experimental
1H NMR spectra were recorded on a BrukerꢀAVANCEꢀ600
spectrometer (600.00 MHz). Chemical shifts were measured
experimentally relatively to DMSOꢀd6 and given in δ scale. IR
spectra were recorded on a VECTOR 22 spectrometer in KBr
pellets. Melting points were determined on a Boetius heating
stage. Methyl chlorophenylpyrotartrate (5a) (see Ref. 40) and
methyl 3ꢀchloroꢀ2ꢀoxoꢀ5ꢀphenylpentanoate (5b) (see Ref. 41)
were obtained according to the known procedures. Mass spectra
EI were obtained on a TRACE MS quadrupole mass spectroꢀ
meter (ThermoQuest). The inflow of the sample was made by a
direct injection with water cooling (DIP). In the mass spectra, the
peaks of ions with relative intensity less than 5% are not given.
The masses of polyisotopic (Se) molecular ions are given in bold.
Methyl 3ꢀbromoꢀ2ꢀoxononanoate (5c). Potassium tertꢀbutꢀ
oxide (2.5 g, 22 mmol) was added in small portions to a solution
of heptanal (2.5 g, 22 mmol) and methyl dichloroacetate (3.1 g,
22 mmol) in THF (150 mL) under argon at –10—–15 °C. The
mixture was stirred for 1 h at this temperature and for 5 h at
room temperature, poured into 20% aqueous NaCl. The organic
layer was separated, the aqueous layer was extracted with AcOEt
(2×20 mL). The organic layer and the extracts were combined,
dried with MgSO4, the solvent was evaporated, and the residue
was dissolved in THF (150 mL). Magnesium bromide (3 g,
16 mmol) was added in small portions to the thus obtained
solution under argon at 0—–5 °C. The reaction mixture was
stirred for 2 h at room temperature, kept for ~14 h, and poured
into 20% aq. NaBr. The organic layer was separated, the aqueous
layer was extracted with ethyl acetate (2×20 mL). The organic
layer and the extracts were combined, dried with MgSO4, and
the solvent was evaporated to obtain compound 5c (4 g, 95%),
orange oily liquid. IR, ν/cm–1: 2957, 2930, 2859, 1737 (C=O),
1458, 1438. 1H NMR (CDCl3), δ: 0.88 (t, 3 H, CH3(CH2)5,
J = 7.0 Hz); 1.22—2.22 (m, 10 H, CH3(CH2)5); 3.91 (s, 3 H,
OCH3); 4.90—4.95 (m, Хꢀpart of ABXꢀsystem, 1 H, CHBr,
JA,X + JB,X = 14.7 Hz).
N,N´ꢀDiphenylselenourea (6) was obtained similarly to
NꢀnꢀbutylꢀN´ꢀcyclohexylselenourea42 using phenylisocyanide
and aniline instead of cyclohexylisocyanide and nꢀbutylamine,
respectively. A powder of gray selenium (2.4 g, 30 mmol) and
aniline (2.8 g, 30 mmol) was added to a solution of phenylꢀ
isocyanide43 (3.4 g, 33 mmol) in THF (40 mL). The reaction
mixture was stirred for 2 h at 65 °C. A precipitate formed was
filtered off and washed with THF to obtain compound 6 (6.1 g,
74%) (gray crystals), m.p. 188—190 °C (from EtOH) (cf. Ref. 32:
m.p. 185—186 °C). The filtrate was concentrated, the residue
was recrystallized from EtOH to additionally obtain compound 6
(1 g, 12%). Found (%): C, 56.72; H, 4.18; N, 9.66. C13H12N2Se.
Methyl 5ꢀhexylꢀ4ꢀhydroxyꢀ3ꢀphenylꢀ2ꢀphenyliminoselenazolꢀ
idineꢀ4ꢀcarboxylate (7c) was obtained similarly to ester 7b from
methyl 3ꢀbromoꢀ2ꢀoxononanoate (5c) (3 g, 13.6 mmol). The
yield of compound 7c was 2 g (36%) (brown oil). Found (%):
C, 60.43; H, 6.11; N, 6.07. C23H28N2O3Se. Calculated (%):
C, 60.13; H, 6.14; N, 6.10. IR, ν/cm–1: 3489 (OH), 3369—2854,
1730 (C=O), 1637, 1589. 1H NMR (CDCl3), δ: 0.86 (t, 3 H,
CH3(CH2)5, J = 7.3 Hz); 0.89 (t, 3 H, CH3(CH2)5, J = 7.0 Hz);
1.18—1.99 (m, 2×10 H, 2 CH3(CH2)5); 3.66, 3.89 (both s,
3 H each, OCH3); 4.33—4.37 (m, Хꢀpart of ABXꢀsystem, 1 H,
CH, JA,X + JB,X = 15.0 Hz); 4.43—4.49 (m, Хꢀpart of
ABXꢀsystem, 1 H, CH, JA,X + JB,X = 15.4 Hz); 6.88—7.55 (m,
2×11 H, 2×2 C6H5 + 2 OH). MS, m/z (Irel (%)): 462 (10), 461
(18), 460 (41), 459 (19), 458 (22), 457 (14), 456 (9) ([M]•+),
403 (7), 402 (9), 401 (37), 400 (5), 399 (20), 398 (8), 397 (7),
298 (7), 288 (6), 287 (14), 286 (6), 275 (7), 274 (7), 273 (9),
271 (5), 268 (8), 267 (10), 213 (6), 212 (13), 196 (51), 195 (99),
Calculated (%): C, 56.74; H, 4.39; N, 10.18. IR, ν/cm–1
:
3169—2999, 1598, 1590, 1547, 1524, 1492. 1H NMR, δ:
7.16 (dd, 2 H, 2 pꢀHPh, J = 7.6 Hz, J = 7.1 Hz); 7.33 (dd, 4 H,
4 mꢀHPh, J = 8.1 Hz, J = 7.6 Hz); 7.39 (d, 4 H, 4 oꢀHPh
J = 7.6 Hz); 10.11 (s, 2 H, 2 NH).
,
Methyl 4ꢀhydroxyꢀ3,5ꢀdiphenylꢀ2ꢀphenyliminoselenazolidineꢀ
4ꢀcarboxylate (7a). Sodium acetate (3.7 g, 45.5 mmol) was

1300
Russ.Chem.Bull., Int.Ed., Vol. 58, No. 6, June, 2009
Mamedov et al.
194 (100), 193 (21), 191 (10), 190 (6), 183 (8), 179 (9), 178 (5),
177 (29), 175 (14), 174 (6), 173 (8), 172 (5), 171 (11), 169 (6),
168 (11), 167 (12), 166 (6), 135 (8), 133 (5), 132 (6), 130 (7),
127 (13), 120 (23), 119 (16), 118 (17), 117 (16), 115 (6), 113 (6),
109 (5), 107 (5), 104 (16), 103 (18), 95 (7), 94 (24), 93 (80), 92
(53), 91 (49), 90 (6), 78 (10), 77 (77).
92 (6), 90 (20), 77 (19). The filtrate was concentrated, the residue
was worked up with water (5 mL), a precipitate was filtered
off, dried in air, and recrystallized from PriOH to obtain
N,N´ꢀdiphenylurea 14 (0.12 g, 26%), m.p. 187—189 °C. IR,
1
ν/cm–1: 3327—2849, 1651, 1595, 1556, 1497. H NMR, δ: 7.16
(dd, 2 H, 2 pꢀHPh, J = 7.6 Hz, J = 7.1 Hz); 7.33 (dd, 4 H,
1ꢀPhenyliminoꢀ3ꢀphenylselenazolo[3,4ꢀa]quinoxalinꢀ4(5H)ꢀ
one (10a). A solution of 1,2ꢀphenylenediamine (3a) (0.2 g,
1.85 mmol) and ester 7a (0.8 g, 1.85 mmol) in AcOH (10 mL)
was refluxed for 2 h. Gray selenium (75 mg) was decanted
from the hot reaction mixture. The crystals precipitated from
the filtrate on cooling were filtered off to obtain analytically
pure compound 10a (72 mg, 9%) (bright yellow crystals),
m.p. 290—293 °C. Found (%): C, 63.45; H, 3.60; N, 10.12.
C22H15N3OSe. Calculated (%): C, 63.47; H, 3.63; N, 10.09.
IR, ν/cm–1: 3182—2767 (NH), 1674 (C=O), 1619 (C=N),
4 mꢀHPh, J = 8.1 Hz, J = 7.6 Hz); 7.39 (d, 4 H, 4 oꢀHPh,
J = 7.6 Hz); 10.11 (s, 2 H, 2 NH). The aqueous layer was
extracted with ethyl acetate (3×20 mL). Ethyl acetate was
evaporated, the residue was worked up with diethyl ether,
and an orange precipitate was filtered off to obtain acetanylide
(19 mg, 32%), m.p. 111—113 °C (cf. Ref. 44: m.p. 113 °C).
IR, ν/cm–1: 3292—2853 (NH), 1664 (C=O), 1619, 1599, 1556.
1H NMR, δ: 2.03 (s, 3 H, COCH3); 7.21 (dd, 1 H, pꢀHPh
,
J = 7.8 Hz, J = 7.3 Hz); 7.27 (dd, 2 H, 2 mꢀHPh, J = 7.8 Hz,
J = 7.3 Hz); 7.56 (d, 2 H, 2 oꢀHPh, J = 7.8 Hz); 9.88 (s, 1 H, NH).
7,8ꢀDimethylꢀ1ꢀphenyliminoꢀ3ꢀ(2ꢀphenylethyl)selenazoloꢀ
[3,4ꢀa]quinoxalinꢀ4(5H)ꢀone (11). A solution of 4,5ꢀdimethylꢀ
1,2ꢀphenylenediamine (3d) (0.2 g, 1.46 mmol) and ester 7b
(0.7 g, 1.46 mmol) was refluxed for 1 h in AcOH (5 mL). A light
green precipitate was filtered off, washed with AcOH, and dried
in air to obtain compound 11 (0.18 g, 21%) (mustard crystals),
m.p. >300 °C. Found (%): C, 65.85; H, 4.98; N, 8.57. C26H23N3OSe.
1
1605, 1586. H NMR, δ: 7.07—7.46 (m, 13 H, 2 C6H5 + H(6) +
H(7) + H(8)); 9.29 (d, 1 H, H(9), J = 8.6 Hz); 11.09 (s, 1 H,
NH). MS, m/z (Irel (%)): 419 (6), 418 (7), 417 (30), 415 (15),
414 (6), 413 (6) ([M]•+), 316 (9), 315 (8), 314 (50), 312 (25),
311 (7), 310 (9), 236 (7), 235 (40), 234 (100), 207 (8), 206 (31),
205 (33), 169 (25), 167 (14), 165 (5), 160 (10), 158 (6), 117 (10),
104 (7), 103 (7), 90 (5), 89 (15), 77 (19).
1ꢀPhenyliminoꢀ3ꢀ(2ꢀphenylethyl)selenazolo[3,4ꢀa]quinoxꢀ
alinꢀ4(5H)ꢀone (10b). A solution of 1,2ꢀphenylenediamine (3a)
(0.23 g, 2.09 mmol) and ester 7b (1 g, 2.09 mmol) was refluxed
for 1 min in AcOH (5 mL). A precipitate was filtered off, washed
with AcOH, and dried in air to obtain compound 10b (0.5 g,
54%) (grayish green crystals), m.p. 273—275 °C (from
DMF). Found (%): C, 64.52; H, 4.47; N, 8.94. C24H19N3OSe.
Calculated (%): C, 66.10; H, 4.91; N, 8.89. IR, ν/cm–1
:
1
3170—2874 (NH), 1668 (C=O), 1617 (C=N), 1589. H NMR,
δ: 2.16, 2.17 (both s, 3 H each, CH3); 2.81—2.85 (m, 2 H,
PhCH2CH2); 3.51—3.55 (m, 2 H, PhCH2CH2); 6.84 (s, 1 H,
H(6)); 6.99—7.45 (m, 10 H, 2 C6H5); 9.11 (s, 1 H, H(9)); 10.93
(s, 1 H, NH).
7ꢀMethylꢀ1ꢀphenyliminoꢀ3ꢀ(2ꢀphenylethyl)selenazoloꢀ
[3,4ꢀa]quinoxalinꢀ4(5H)ꢀone (12a) and 8ꢀmethylꢀ1ꢀphenyliminoꢀ
3ꢀ(2ꢀphenylethyl)selenazolo[3,4ꢀa]quinoxalinꢀ4(5H)ꢀone (13a)
(a mixture of isomers 12a + 13a in the percentage ratio 65 : 35).
A solution of 4ꢀmethylꢀ1,2ꢀphenylenediamine (3b) (0.13 g,
1.0 mmol) and ester 7b (0.5 g, 1.0 mmol) in AcOH (5 mL) was
refluxed for 1 h. A yellow precipitate was filtered off, washed
with AcOH, and dried in air to obtain a 12a + 13a mixture
(0.11 g, 19%) (light green crystals), m.p. 268—270 °C (from
DMF). Found (%): C, 65.83; H, 4.59; N, 9.12. C25H21N3OSe.
Calculated (%): C, 64.87; H, 4.31; N, 9.46. IR, ν/cm–1
:
1
3187—2766 (NH), 1669 (C=O), 1621 (C=N), 1590. H NMR,
δ: 2.82—2.86 (m, 2 H, PhCH2CH2); 3.52—3.54 (m, 2 H,
PhCH2CH2); 6.99—7.45 (m, 13 H, 2 C6H5 + H(6) + H(7) +
H(8)); 9.29 (d, 1 H, H(9), J = 8.4 Hz); 11.06 (s, 1 H, NH).
3ꢀHexylꢀ1ꢀphenyliminoselenazolo[3,4ꢀa]quinoxalinꢀ
4(5H)ꢀone (10c). A solution of 1,2ꢀphenylenediamine (3a)
(0.05 g, 0.44 mmol) and ester 7c (0.2 g, 0.44 mmol) in AcOH
(5 mL) was refluxed for 2 h. Gray selenium (5 mg) was decanted
from the hot reaction mixture. The crystals precipitated
from the filtrate on cooling were filtered off to obtain analyꢀ
tically pure compound 10c (54 mg, 30%) (light green crystals),
m.p. 199—200 °C. Found (%): C, 61.92; H, 5.39; N, 9.75.
C22H23N3OSe. Calculated (%): C, 62.26; H, 5.46; N, 9.90.
IR, ν/cm–1: 3182—2767 (NH), 1674 (C=O), 1619 (C=N), 1605,
1586. 1H NMR, δ: 0.82 (t, 3 H, CH2CH2(CH2)3CH3, J = 6.8 Hz);
1.22—1.32 (m, 6 H, CH2CH2(CH2)3CH3); 1.51 (quint, 2 H,
CH2CH2(CH2)3CH3, J = 7.7 Hz); 3.25 (t, 2 H, CH2CH2ꢀ
Calculated (%): C, 65.50; H, 4.62; N, 9.17. IR, ν/cm–1
:
1
3173—2890 (NH), 1671 (C=O), 1618 (C=N), 1589. H NMR,
δ: 2.25, 2.26 (both s, 3 H each, CH3); 2.81—2.85 (m, 2×2 H,
2 PhCH2CH2); 3.51—3.55 (m, 2×2 H, 2 PhCH2CH2); 6.86—7.45
(m, 24 H, 4 C6H5 + 2 H(6) + H(7) + H(8)); 9.15 (s, 1 H,
H(9)); 9.17 (d, 1 H, H(9), J = 8.4 Hz); 10.98, 11.01 (both s,
1 H each, NH).
8ꢀNitroꢀ1ꢀphenyliminoꢀ3ꢀ(2ꢀphenylethyl)selenazolo[3,4ꢀa]ꢀ
quinoxalinꢀ4(5H)ꢀone (13b). A solution of 4ꢀnitroꢀ1,2ꢀpheꢀ
nylenediamine (3c) (0.16 g, 1.04 mmol) and ester 7b (0.5 g,
1.04 mmol) in AcOH (5 mL) was refluxed for 4.5 h. A precipitate
was filtered off, washed with AcOH, and dried in air to
obtain compound 13b (0.1 g, 20%) (red crystals), m.p. >300 °C.
Found (%): C, 58.90; H, 3.87; N, 10.93. C24H18N4O3Se.
(CH2)3CH3, J = 7.7 Hz); 7.00—7.18 (m, 6 H, 2 oꢀHPh + pꢀHPh
+
H(6) + H(7) + H(8)); 7.41—7.45 (t, 2 H, 2 mꢀHPh, J = 7.9 Hz);
9.29 (d, 1 H, H(9), J = 7.3 Hz); 11.02 (s, 1 H, NH). MS, m/z
(Irel (%)): 427 (16), 426 (20), 425 (80), 424 (10), 423 (41),
422 (15), 421 (14) ([M]•+), 324 (8), 323 (8), 322 (45), 321 (5),
320 (23), 319 (9), 318 (9), 267 (6), 266 (15), 265 (26), 264 (8),
263 (14), 262 (7), 261 (5), 254 (8), 253 (28), 252 (34), 251 (33),
250 (20), 249 (19), 248 (9), 242 (18), 241 (73), 240 (23), 239 (7),
213 (9), 212 (7), 211 (19), 199 (29), 198 (30), 197 (38), 187 (6),
186 (41), 185 (100), 184 (45), 183 (7), 181 (7), 174 (10),
173 (40), 172 (21), 171 (79), 169 (12), 167 (11), 161 (11), 160 (37),
156 (11), 155 (8), 147 (5), 144 (6), 143 (21), 142 (6), 132 (6),
131 (8), 118 (8), 117 (5), 116 (6), 104 (13), 103 (9), 102 (15),
Calculated (%): C, 58.90; H, 3.71; N, 11.45. IR, ν/cm–1
:
3139—2919 (NH), 1697 (C=O), 1675, 1617 (C=N), 1592.
1H NMR, δ: 2.83—2.87 (m, 2 H, PhCH2CH2); 3.51—3.55 (m,
2 H, PhCH2CH2); 7.03—7.56 (m, 11 H, 2 C6H5 + H(6));
8.07 (dd, 1 H, H(7), J = 8.8 Hz, J = 2.6 Hz); 10.35 (d, 1 H,
H(9), J = 2.6 Hz); 11.64 (s, 1 H, NH).
Xꢀray diffraction analysis. The study of a monocrystal of
compound 13b was performed in the Division of Xꢀray Structural

Selenazolo[3,4ꢀa]quinoxalynꢀ4(5H)ꢀones
Russ.Chem.Bull., Int.Ed., Vol. 58, No. 6, June, 2009
1301
Studies of the Community Center on the basis of Laboratory of
Diffraction Research Methods in the A. E. Arbuzov Institute
of Organic and Physical Chemistry of the Kazan Research Center
of the Russian Academy of Sciences. The experiments were
performed on a Bruker AXS SMART APEX II automatic threeꢀ
circle diffractometer equipped with a plane CCD detector.
Crystals C24H18N4O3Se•C3H7NO, M = 562.48, monoclinic;
at 23 °C a = 15.3058(11) Å, b = 8.0597(6) Å, c = 20.6632(15) Å,
5. V. P. Litvinov, V. D. D´yachenko, Usp. Khim., 1997, 66,
1025 [Russ. Chem. Rev. (Engl. Transl.), 1997, 66, 923].
6. T. Wirth, Tetrahedron, 1999, 55, 1.
7. Organoselenium Chemistry: A Practical Approach, Ed. T. G. Back,
Oxford University, Oxford, 1999.
8. H. E. Ganther, Bioorg. Med. Chem., 2001, 9, 1459.
9. G. Mugesh, W.ꢀW. Du Mont, H. Sies, Chem. Rev., 2001,
101, 2125.
10. C. W. Nogueira, G. Zeni, J. B. T. Rocha, Chem. Rev., 2004,
104, 6255.
11. R. N. Hanson, R. W. Giese, M. A. Davis, S. M. Costello,
J. Med. Chem., 1978, 21, 496.
12. Y. Kumar, R. Green, D. S. Wise, L. L. Worting, L. B.
Townsend, J. Med. Chem., 1993, 36, 3849.
13. P. Franchetti, L. Cappellacci, G. A. Sheikha, H. N. Jayaram,
V. V. Gurudutt, T. Sint, B. P. Schneider, W. D. Jones, B. M.
Goldstein, G. Perra, A. De Montis, A. G. Loi, P. La Colla,
M. Grifantini, J. Med. Chem., 1997, 40, 1731.
14. C. Ip, H. J. Thompson, Z. Zhu, H. E. Ganther, Cancer Res.,
2000, 60, 2862.
15. D. Medina, H. Thompson, H. Ganther, Nutr. Cancer, 2001,
40, 12.
16. R. Sinha, E. Unni, H. Ganther, D. Medina, Biochem.
Pharmacol., 2001, 61, 311.
17. S.ꢀI. Fujiwara, Y. Shikano, T. Shinꢀike, N. Kambe, N. Sonjda,
J. Org. Chem., 2002, 67, 6275.
18. G. L. Sommen, A. Linden, H. Heimgartner, Heterocycles,
2005, 65, 1903.
19. G. L. Sommen, A. Linden, H. Heimgartner, Tetrahedron,
2006, 62, 3344.
20. S. H. Ueda, H. Terauchi, K. Suzuci, A. Yano, M. Matsumoto,
T. Kubo, H. Minato, Y. Arai, J.ꢀI. Tsuji, N. Watanabe,
Bioorg. Med. Chem. Lett., 2005, 15, 1361.
21. S. H. Ueda, H. Terauchi, K. Suzuci, N. Watanabe, Tetraheꢀ
dron Lett., 2005, 46, 233.
22. W. M. ElꢀSayed, W. A. Hussin, M. R. Franklin, Mutation
Research, 2007, 627, 136.
β = 90.748(1)°, V = 2548.8(3) Å3, Z = 4, dcalc = 1.466 g cm–3
,
space group P21/n, μ(MoꢀKα) = 15.17 cm–1, F(000) = 1152.
Parameters of the unit cell and intensities of 18396 reflections
(Rint = 0.0224), from which 3913 were observed reflection
with I ≥ 2σ, were measured at 23 °C on MoꢀKα irradiation
(λ(MoꢀKα) = 0.71073 Å, a graphite monochromator, ϕꢀ and
ωꢀscanning; the region of measurement: the range on the
indices –19 ≤ h ≤ 19, –10 ≤ k ≤ 10, –25 ≤ l ≤ 25, θmin = 2.66° and
θ
= 26.50°). The allowance for the absorption was made
umsianxg the SADABS program.45 The structure was decoded by
the direct method and refined by the least squares method first
in isotropic, then, in anisotropic approximation for all the
nonhydrogen atoms. The coordinates of the hydrogen atoms
of the amino group were found from the differential series of
electron density and refined isotropically. The coordinates
of other hydrogen atoms were calculated based on the stereoꢀ
chemical criteria and refined using the corresponding riding
model. The final divergence factor values: R1 = 0.0400,
wR2 = 0.1049 on 3913 independent reflections with I ≥ 2σ(I),
R1 = 0.0582, wR2 = 0.1153 on all the data, GOOF 1.027, the
number of parameters 281. The maximum and the minimum
peaks are 0.879 and –0.503 e A–3. The data collection and
processing, as well as refinement of the unit cell parameters were
performed using the APEX2 program.46 All calculations on
determining and refining the structures were performed using
the SHELXTL47 and WinGX48 programs, the analysis of the
intermolecular interactions and the figures of the molecules were
made using the PLATON program.37 The atom coordinates
in the structure 13b and their temperature parameters were
deposited with the Cambridge Structural Database (http://
www.ccdc.cam.ac.uk; the deposit number is CCDC 703890).
23. W. M. ElꢀSayed, T. AboulꢀFadl, J. G. Lamb, J. C. Roberts,
M. R. Franklin, Toxicology, 2006, 220, 179.
24. M. R. Franklin, Ph. J. Moos, W. M. ElꢀSayed, T. Aboutꢀ
Fald, J. C. Roberts, Chem.ꢀBiol. Interact., 2007, 168, 211.
25. Y. Xie, M. D. Short, P. B. Cassidy, J. C. Roberts, Bioorg.
Med. Chem. Lett., 2001, 11, 2911.
26. M. D. Short, Y. Xie, L. Li, P. B. Cassidy, J. C. Roberts,
J. Med. Chem., 2003, 46, 3308.
27. V. A. Mamedov, Ya. A. Levin, Khim. Geterotsikl. Soedin., 1996,
1005 [Chem. Heterocycl. Compd. (Engl. Transl.), 1996, 32].
28. V. A. Mamedov, A. A. Kalinin, A. T. Gubaidullin, I. Z.
Nurkhametova, I. A. Litvinov, Ya. A. Levin, Khim. Geteroꢀ
tsikl. Soedin., 1999, 1664 [Chem. Heterocycl. Compd. (Engl.
Transl.), 1999, 35].
29. V. A. Mamedov, I. Z. Nurkhametova, S. K. Kotovskaya,
A. T. Gubaidullin, Ya. A. Levin, I. A. Litvinov, V. N. Charushin,
Izv. Akad. Nauk, Ser. Khim., 2004, 2462 [Russ. Chem. Bull.,
Int. Ed., 2004, 53, 2568].
This work was financially supported by the Russian
Foundation for Basic Research (Project No. 07ꢀ03ꢀ00613ꢀa)
and the Federal Purposed Program “Study and Elaboraꢀ
tion on Priority Directions in Development of Russian
Scientific and Technical Complex in 2007—2012” (State
Contract No. 02.512.11.2237).
References
1. V. A. Mamedov, A. M. Murtazina, L. P. Sysoeva, E. V.
Mironova, S. K. Latypov, A. A. Balandina, S. F. Kadyrova,
A. T. Gubaidullin, I. A. Litvinov, Zh. Org. Khim., 2008, 44,
923 [Russ. J. Org. Chem. (Engl. Transl.), 2008, 44].
2. Organic Selenium Compounds. Their Chemistry and Biology,
Eds L. Klayman, W. H. H. Gunther, J. Wiley and Sons, New
York, 1973.
3. C. Paulmier, Selenium Reagents and Intermediates in Organic
Synthesis, Pergamon Press, Oxford, 1986, Vol. 1.
4. Organoselenium Chemistry, Ed. D. Liotta, Wiley, New York,
1987.
30. V. A. Mamedov, I. Z. Nurkhametova, A. T. Gubaidullin,
I. A. Litvinov, S. Tsuboi, Heterocycles, 2004, 63, 1783.
31. V. A. Mamedov, N. A. Zhukova, T. N. Beschastnova, Ya. A.
Levin, A. T. Gubaidullin, I. A. Litvinov, Izv. Akad. Nauk,
Ser. Khim., 2007, 2255 [Russ. Chem. Bull., Int. Ed., 2007,
56, 2308].

1302
Russ.Chem.Bull., Int.Ed., Vol. 58, No. 6, June, 2009
Mamedov et al.
32. M. Lipp, F. Dallacker, I. Meier zu Kocker, Monatsh. Chem.,
1959, 90, 41.
41. I.ꢀR. Lin, A. T. Gubaidullin, V. A. Mamedov, S. Tsuboi,
Tetrahedron, 2003, 59, 1781.
33. V. A. Mamedov, I. Z. Nurkhametova, R. R. Shagidullin,
A. V. Chernova, Ya. A. Levin, Khim. Geterotsikl. Soedin.,
1999, 975 [Chem. Heterocycl. Compd. (Engl. Transl.), 1999, 35].
34. D. D. Davey, P. W. Erhardt, E. H. Cantor, S. S. Greenberg,
W. R. Ingebretsen, J. Wiggins, J. Med. Chem., 1991, 34,
2671.
35. V. A. Mamedov, A. A. Kalinin, A. T. Gubaidullin, I. A.
Litvinov, N. M. Azancheev, Ya. A. Levin, Zh. Org. Khim.,
2004, 123 [Russ. J. Org. Chem. (Engl. Transl.), 2004, 40].
36. A. T. Gubaidullin, V. A. Mamedov, L. A. Litvinov, Arkivok,
2004, 12, 80.
42. N. Sonoda, G. Yamamoto, S. Tsutsumi, Bull. Chem. Soc.
Jpn, 1972, 45, 2937.
43. R. Appel, R. Kleinstuck, K.ꢀD. Ziehn, Angew. Chem., Int.
Ed., 1971, 10, 132.
44. A. F. Odell, C. W. Hines, J. Am. Chem. Soc., 1913, 35, 81.
45. G. M. Sheldrick, SADABS, Program for Empirical Xꢀray
Absorption Correction, BrukerꢀNonius, 1990—2004.
46. Bruker, M86ꢀE01078 APEX2 User Manual, Version 2, Bruker
AXS, Madison (Wisconsin, USA), 2006.
47. G. M. Sheldrick, SHELXTL, Version 6.12, Structure Deterꢀ
mination Software Suite, Bruker AXS, Madison (Wisconsin,
USA), 2000.
37. A. L. Spek, Acta Crystallogr., Sect. A, 1990, 46, 34.
38. E. A. Meyer, R. K. Kastellano, F. Diederich, Angew. Chem.,
Int. Ed., 2003, 42, 1210.
48. L. J. Farrugia, J. Appl. Crystallogr., 1999, 32, 837.
39. NIST/EPA/NIH Mass Spectral Library (NIST 98) Se8
NIST: #158071 ID:#70745.
40. V. A. Mamedov, I. A. Nuretdinov, Izv. Akad. Nauk, Ser.
Khim., 1992, 2159 [Russ. Chem. Bull. (Engl. Transl.), 1992,
41, 1690].
Received November 25, 2008;
in revised form February 13, 2009