An efficient preparation of new homoallylamines and α-aminonitriles bearing furyl and thienyl rings

Article abstract of DOI:10.1002/jhet.5570450344

(Chemical Equation Presented) New diverse N-aryl-N-[1-furyl(thienyl)but-3- enyl]amines (homoallylamines) or 2-(N-arylmethylamino)-2-furyl(thienyl) acetonitriles (α-aminonitriles) were easily prepared in good to excellent yields by an indium-mediated Barbi

Full text of DOI:10.1002/jhet.5570450344

May-Jun 2008
927
An Efficient Preparation of New Homoallylamines and
α-Aminonitriles Bearing Furyl and Thienyl Rings
Leonor Y. Vargas Méndez and Vladimir V. Kouznetsov*
Laboratorio de Química Orgánica y Biomolecular, Escuela de Química, Universidad Industrial de Santander,
A.A. 678, Bucaramanga, Colombia.
Received June 22, 2007
R
R
O
NH
X
NH2
+
H
X
R1
R = H, Cl
R1 = CN, CH2CH=CH2
X = 2 (3)-Fu
X = 2 (3)-Thie
New diverse N-aryl-N-[1-furyl(thienyl)but-3-enyl]amines (homoallylamines) or 2-(N-arylmethylamino)-
2-furyl(thienyl)acetonitriles (α-aminonitriles) were easily prepared in good to excellent yields by an
indium-mediated Barbier-type reaction between N-hetarylaldimines and allyl bromide in MeOH or a direct
three component reaction between anilines, hetaryl aldehydes and trimethylsilyl cyanide in the presence of
a catalytic amount of molecular iodine at room temperature, respectively. The entire set of amines was
characterized by IR, 1H and 13C NMR spectroscopy.
J. Heterocyclic Chem., 45, 927 (2008).
INTRODUCTION
characterization of this type of molecules are reported in
this paper.
N-Substituted but-3-enylamines, - homoallylamines, are
an important and interesting class of organic molecules,
which have been always the focus of attention for organic,
bioorganic and medicinal chemists due to their many
synthetic applications [1,2] as well as their biological
properties [3-5]. α-Aminonitriles are also important
intermediates for several amino acids as well as for
popular bifunctional synthons that have found numerous
synthetic applications [6]. Both these substructures are
usually prepared from azomethines via nucleophilic
addition reactions such as the Grignard-Barbier allylations
[7-10] and Strecker-type reactions [11-16]. The respective
allyl or cyanide ion addition reactions provide an access
to new drug-like molecules by introducing a stereogenic
center and a carbon-carbon bond in one step. So,
allylation and cyanation reactions are important reactions
in synthetic organic chemistry and medicinal chemistry.
Moreover, oxygen and sulfur heterocycles are frequently
found in privileged structures (pharmacophores); among
them, furan and thiophene derivatives represent good
candidates for bioscreening of diverse types of activities.
With these fact in mind and as a development of our
medicinal program directed to small molecules for drug
delivery, we were particularly interested in diverse N-
RESULTS AND DISCUSSION
In our quest for new homoallylamines and related
compounds with antifungal and antiparasitic properties,
we exploited with some success Grignard reaction
between imines and preformed allylmagnesium bromide
in dry bipolar aprotic solvents (Et2O, THF, etc) [3-5].
However, there are still limitations in these reactions:
first, the scope of application to imines is still narrow
because of their stability; second, imines are less reactive
compared with the corresponding carbonyl compounds
because of their low electrophilicity, which makes it
difficult to realize a one-pot sequential version of the
Grignard multicomponente reaction.
To prepare new diverse N-aryl-N-[1-furyl(thienyl)but-
3-enyl]amines, now we employed the Barbier-type
reaction, when the organometallic reagent has low
reactivity toward water or alcoholic solvents and is
formed in the reaction mediated by mixing the metal,
halide and electrophilic substrate in a one-pot reaction.
The N-furylaldimines 1 and N-thienylaldimines 2, the
main starting materials in our research on this allylation
reaction, were easily prepared from commercially
available 2-(3)-furancarboxyaldehydes or 2-(3)-thiophen-
carboxyaldehydes and substituted anilines, according to
published methods [17,18]. Reactions of aldimines 1,2
with the allyl indium reagent generated in situ by addition
of allyl bromide to a suspension of indium powder were
realized in dry MeOH (Scheme I).
aryl-N-[1-furyl(thienyl)but-3-enyl]amines
(homoallyl-
amines) or (2-(N-arylmethylamino)-2-furyl(thienyl) aceto-
nitriles (α-aminonitriles) that could serve as useful
precursors to many drug-like molecules and interesting
biological models in our quest for compounds with
antifungal and antiparasitic properties [3-5]. The results of
After a standard work-up, this reaction furnished the
desired homoallylic amines 3 and 4 as viscous oils in
our
investigation
on
synthesis
and
spectral

928
L. Y. V. Méndez and V. V. Kouznetsov
Vol 45
good to excellent yields (Table 1). The products were
purified by chromatography on a short silica gel column.
In the 1H nmr spectra of the amines 3 and 4, the protons of
the butene chain gave rise to very characteristic groups of
signals. The triplet (J = 6.2-6.3 Hz) from a proton at C-4
was observed in the region δ 4.39-4.60 ppm. A signal for
two protons corresponding to the group 3-CH2 appeared
in the region δ 2.60-2.66 ppm. The two multiplets
between δ 5.26-5.17 and δ 5.94-5.70 ppm are due to the
olefinic hydrogens, –CH2= and –CH=, respectively. The ir
spectra of homoallylamines 3,4 showed a characteristic
band for the amino group in the region of 3415-3410 and
1605-1601 cm-1.
nitriles (5,6) that could be considered as amine
analogues of prepared compounds 3,4. In comparison
with the homoallylamines preparation, their synthesis
can be easily performed via three-component
condensation of heteroaldehydes, anilines and either
hydrogen cyanide or its alkaline metal cyanides.
Although catalyst-free three-component Strecker
reaction in acetonitrile was reported [14], we
considered that I2-catalyzed three-component coupling
of chosen aldehydes and anilines in the presence of
trimethylsilyl cyanide (TMSCN) [13] would be
appropriated to generate new α-amino nitriles needed
in our future pharmacological investigation.
The mass spectra of these compounds contain low-
intensity (< 1-5%) molecular ion peaks which agree with
the expected molecular mass. The maximum peaks belong
to the fragmentation (M-C3H5)+..
So, new homoallylamines bearing furyl or thienyl rings
were easily obtained using an allyl bromide-indium-
methanol system at room temperature that could be
utilized in multi-component Grignard-type reactions and
avoids the use of anhydrous ether.
Thus, the treatment of the same aldehydes and
anilines with TMSCN in the presence of a catalytic
amount of iodine in MeCN at room temperature
afforded 2-(N-arylmethylamino)-2-furyl(thienyl)aceto-
nitriles (5,6) in good to excellent yields (Scheme 1,
Table 1). The obtained α-aminonitriles showed in the ir
spectra the characteristic NH and CN bands appearing
in the region of 3367-3356 and 2241-2237 cm-1,
respectively. Their structures were also consistent with
their 1H- and 13C-nmr spectra and supported by the
Scheme I
1
mass spectrometric data. In the H nmr spectra of the
R
α-aminonitriles 5,6, the aliphatic proton H-2 resonates
between 5.50 and 5.28 ppm as a singlet (comp. 5a,b
and 6b) or as a doublet (J = 8.1-8.8 Hz) (comp. 6a,c),
due to the interaction with NH group.
R
N
NH2
+
O
dry Et2O
Na2SO4, r.t.
X
X
R = H, Cl
H
H
So, new 2-hetarylacetonitriles (5,6) were easily
obtained using a simple one-pot procedure where iodine
acts efficiently as a mild Lewis acid that could be a useful
and inexpensive catalyst for the generation of α-
aminonitriles based on heteroaldehydes.
1,2
X = 2 (3)-Fu
X = 2 (3)-Thie
Me3SiCN/I2
MeCN, r.t
BrCH2CH=CH2/In
dry methanol, r.t
R
R
In summary, two series of new potentially bioactive
secondary amines were prepared. The import features of
the used methods include a) operational simplicity, b)
good yields of the desired amines, c) short reaction times.
All products 3-6 were evaluated as possible antifungal
agents. These compounds possess from moderate to good
antifungal activity against certain type of fungi
(hialohyphomycetes or dermatophytes) [19].
NH
X
NH
X
C
N
5,6
3,4
Second part of our research was the preparation
of new 2-(N-arylmethylamino)-2-furyl(thienyl)aceto-
Table 1
Comp.
R
X
Molecular
Formula
C14H15NO
C14H14ClNO
C14H15NS
M.W.
(g/mol)
213.28
247.72
229.34
263.79
229.34
263.79
198.22
198.22
214.29
214.29
248.73
MS
(M , m/z)
Yield
(%)
95
57
88
57
97
48
61
62
80
84
88
IR (ν, cm-1)
+
•
3a
3b
4a
4b
4c
4d
5a
5b
6a
6b
6c
H
Cl
H
Cl
H
Cl
H
H
3-O
3-O
2-S
2-S
3-S
3-S
2-O
3-O
2-S
3-S
3-S
213 (M+), 172 [(M-C3H5)+]
247 (M+), 206 [(M-C3H5)+ for 35Cl]
229 (M+), 188 [(M-C3H5)+]
263 (M+), 222 [(M-C3H5)+ for 35Cl]
229 (M+), 188 [(M-C3H5)+]
263 (M+), 222 [(M-C3H5)+ for 35Cl]
198 (M+)
3410, 1601, 1504, 922
3413, 1601, 1497, 922
3405, 1609, 1498, 920
3413, 1595, 1497, 923
3410, 1601, 1504, 918
3413, 1597, 1497, 922
3359, 2241, 1605
3356, 2237, 1605
3356, 2237, 1605
3367, 2237, 1601
3356, 2237, 1601
C14H14ClNS
C14H15NS
C14H14ClNS
C12H10N2O
C12H10N2O
C12H10N2S
C12H10N2S
C13H12ClN2S
198 (M+)
H
H
Cl
214 (M+)
214 (M+)
248 (M+)

May-Jun 2008
An Efficient Preparation of New Homoallylamines and α-Aminonitriles
929
nmr (deuterium chloroform): δ 7.10 (1H, dd, J = 4.5, 1.6 Hz, 5-
HThie), 6.99 (2H, d, J = 8.6 Hz, 3(5)-HAr), 6.88-6.85 (2H, m, 3(4)-
HThie), 6.44 (2H, d, J = 8.6 Hz, 2(6)-HAr), 5.78-5.64 (1H, m,
=CH), 5.14-5.08 (2H, m, CH2=), 4.58 (1H, t, J = 6.6 Hz, 4-H),
4.20 (1H, br.d, H-N), 2.61-2.55 (2H, m, -CH2), 13C nmr (75
MHz): δ 147.9, 145.4, 133.7 (+), 129.0 (2C, +), 126.8 (+), 123.9
(+), 123.7 (+), 122.7, 118.9 (-), 114.9 (2C, +), 53.6 (+), 43.0 (-).
ms: m/z: 263 (molecular ion), 222 [(M-C3H5)+ for 35Cl]. Anal.
Calcd. for C14H14ClNS: C, 63.74; H, 5.35; N, 5.31. Found: C,
63.96; H, 5.56; N, 5.20.
EXPERIMENTAL
Melting points were uncorrected and measured in a FISHER-
JOHNS melting point apparatus. Infrared spectra were recorded
on an Infralum (Lumex) FT-IR spectrometer as KBr pellets or
neat. The H and 13C nmr spectra were determined on Bruker
1
AM-300, in deuterium chloroform with tetramethylsilane as
internal standard. Data are reported as follows: chemical shifts
(multiplicity, number of protons, coupling constants and group).
On dept-135 spectra, the signals of CH3, CH2 and CH carbons
are shown as positive (+) and negative (-), respectively.
Quaternary carbons are not shown. Mass spectra were recorded
with a HP 5890 A Series II, link to a network Mass selective
detector HP 5972, a spectrometer with 70 eV electron impact
ionization. The purities of the obtained substance were
monitoring by thin layer chromatography on Silufol UV254
sheets. Elemental analyses were performed on a Leco CHN-600
analyzer. Solvents and common reagents obtained from Merck
and Aldrich were reagent grade.
General procedure for the synthesis of N-aryl-N-[1-
furyl(thienyl)but-3-enyl]amines (3,4). To a mixture of the
aldimine 1,2 (2.2 mmol) and indium powder (375 mg, 3.3
mmol) in absolute methanol (10 mL) was added allyl bromide
(800 mg, 0.590 mL, 6.6 mmol). The reaction was stirred
vigorously at room temperature until all the indium had
dissolved (1 h to 4 h), at which time TLC indicated complete
reaction. The reaction mixture was diluted with sat. NH4Cl and
extracted with ethyl acetate. The extract was washed with brine
and dried (Na2SO4). The product was purified by flash column
chromatography on silica gel, using hexanes/ethyl acetate as
eluent. Physicochemical characteristics of the synthesized
homoallylamines 3,4 are given in the Table 1.
N-Phenyl-N-[1-(3-furyl)but-3-enyl]amine (3a). The
compound 3a was obtained in 95 % yield, red oil. ir (potassium
bromide): ν = 3410, 1601, 1504, 922 cm-1. 1H nmr (deuterium
chloroform): δ 7.43 (1H, t, J = 1.7 Hz, 5-HFu), 7.39 (1H, s, 2-
HFu), 7.20 (2H, t, J = 7.5, Hz, 3(5)-HPh), 6.76 (1H, t, J = 7.3 Hz,
4-HPh), 6.66 (1H, d, J = 7.9 Hz, 2(6)-HPh), 6.42 (1H, br.s, 4-HFu),
5.94-5.79 (1H, m, =CH), 5.26-5.17 (2H, m, CH2=), 4.50 (1H, t, J
= 6.3 Hz, 4-H), 2.63 (2H, t, J = 6.8 Hz, -CH2), 13C nmr (75
MHz): δ 147.2, 143.1 (+), 139.5 (+), 134.3 (+), 129.1 (2C, +),
127.7, 118.3 (-), 117.6 (+), 113.5 (2C, +), 109.0 (+), 49.4 (+),
41.0 (-). ms: m/z: 213 (molecular ion), 172 [(M-C3H5)+].
N-Phenyl-N-[1-(3-thienyl)but-3-enyl]amine (4c). The
1
compound 4c was obtained in 97% yield, yellow oil. H nmr
(deuterium chloroform): δ 7.34 (1H, dd, J = 4.9, 3.0 Hz, 5-HThie),
7.20-7.15 (3H, m, 3(5)-HPh, and 2-HThie), 7.11 (1H, dd, J = 5.0,
1.2 Hz, 4-HThie), 6.74 (1H, t, J = 7.3 H, 4-HPh), 6.62 (2H, d, J =
7.7 Hz, 2(6)-HPh), 5.92-5.75 (1H, m, =CH), 5.26-5.18 (2H, m,
CH2=), 4.60 (1H, t, J = 6.5 Hz, 4-H), 2.67 (2H, q, J = 6.7 Hz,
-CH2), 13C nmr (75 MHz): δ 147.2, 144.7, 134.4 (+), 129.1 (2C,
+), 127.7, 126.1 (+), 126.0 (+), 120.8 (+), 118.3 (-), 117.6 (+),
113.6 (+), 53.4 (+), 41.9 (-). ms: m/z: 229 (molecular ion), 188
[(M-C3H5)+]. Anal. Calcd. for C14H15NS: C, 73.32; H, 6.59; N,
6.11. Found: C, 73.50; H, 6.45; N, 6.24.
N-(4-Chlorophenyl)-N-[1-(3-thienyl)but-3-enyl]amine (4d).
1
The compound 4b was obtained in 48 % yield, yellow oil. H
nmr (deuterium chloroform): δ 7.29 (1H, dd, J = 4.9, 3.0 Hz, 5-
HThie), 7.12 (1H, br.d, J = 2.9 Hz, 2-HThie), 7.06 (2H, d, J = 8.8
Hz, 3(5)-HAr), 7.04 (1H, dd, J = 5.3, 1.0 Hz, 4-HThie), 6.48 (2H,
d, J = 8.7 Hz, 2(6)-HAr), 5.84-5.65 (1H, m, =CH), 5.21-5.14 (2H,
m, CH2=), 4.50 (1H, t, J = 6.5 Hz, 4-H), 2.69-2.52 (2H, m, -
CH2), 13C nmr (75 MHz): δ 145.7, 144.2, 134.1 (+), 128.9 (2C,
+), 126.2 (+), 125.9 (+), 122.2, 120.9 (+), 118.5 (-), 114.6 (2C,
+), 53.5 (+), 41.8 (-). ms: m/z: 263 (molecular ion), 222 [(M-
C3H5)+ for 35Cl]. Anal. Calcd. for C14H14ClNS: C, 63.74; H, 5.35;
N, 5.31. Found: C, 63.87; H, 5.55; N, 5.57.
General procedure for the synthesis of 2-(N-arylmethyl-
amino)-2-furyl(thienyl)acetonitriles (5,6). To a mixture of
heteroaldehyde (5.4 mmol), anilines (5.4 mmol), and TSCN
(0.535 mg, 5.4 mmol) in dry MeCN (8 mL) was stirred at room
temperature for 20-30 min. To the reaction mixture was added
the iodine (140 mg, 0.54 mmol). After completion of reaction
(1-3h, TLC), the colored reaction mixture was diluted with sat.
NH4Cl (30 mL) and extracted with ethyl acetate. The extract was
washed with brine and dried (Na2SO4). The product was purified
by flash column chromatography on silica gel, using hexanes/
ethyl acetate as eluent. Physicochemical characteristics of the
synthesized α-aminonitriles 5,6 are given in the Table 1.
Anal. Calcd. for C14H15NO: C, 78.84; H, 7.09; N, 6.57. Found:
C, 78.66; H, 7.16; N, 6.50.
N-(4-Chlorophenyl)-N-[1-(3-furyl)but-3-enyl]amine (3b).
The compound 3b was obtained in 57 % yield, red oil. 1H nmr
(deuterium chloroform): δ 7.38 (1H, t, J = 1.6 Hz, 5-HFu), 7.32
(1H, br.d, J = 0.6 Hz, 2-HFu), 7.09 (2H, d, J = 8.8, Hz, 3(5)-HAr),
6.52 (2H, d, J = 8.8 Hz, 2(6)-HAr), 6.35 (1H, br.t, J = 0.7 Hz, 4-
HFu), 5.85-5.71 (1H, m, =CH), 5.21-5.14 (2H, m, CH2=), 4.39
2-(2-Furyl)-2-(phenylamino)acetonitrile (5a). The
compound 5a was obtained in 61 % yield, red oil. Its spectral
data were in agreement with those reported in literature [12].
2-(3-Furyl)-2-(phenylamino)acetonitrile (5b). The
1
compound 5b was obtained in 62 % yield, red oil. H nmr
(1H, t, J = 6.2 Hz, 4-H), 2.56 (2H, td, J = 6.9, 1.4 Hz, -CH2). 13
C
(deuterium chloroform): δ 7.62 (1H, s, J = 0.9 Hz, 5-HFu), 7.41
(2H, br.t, J = 1.4 Hz, 2-HFu), 7.21 (2H, t, J = 7.6 Hz, 3(5)-HPh),
6.84 (1H, t, J = 7.4 Hz, 4-HPh), 6.70 (2H, d, J = 7.8 Hz, 2(6)-
HPh), 6.47 (1H, s, 4-HFu), 5.27 (1H, s, HC-CN), 3.92 (1H, br.s,
H-N), 13C nmr (75 MHz): δ 144.5 (+), 144.3, 141.0 (+), 129.6
(2C, +), 120.5 (+), 120.1, 117.8, 114.3 (2C, +), 109.1 (+), 42.5
(+). ms: m/z: 198 (molecular ion). Anal. Calcd. for C15H12N2O:
C, 72.71; H, 5.08; N, 14.13. Found: C, 72.66; H, 5.26; N, 14.20.
nmr (75 MHz): δ 145.8, 143.3 (+), 139.5 (+), 134.0 (+), 128.9
(2C, +), 127.3, 121.1, 118.5 (-), 114.6 (2C, +), 108.9 (+), 49.5
(+), 41.0 (-). ms: m/z: 247 (molecular ion), 206 [(M-C3H5)+ for
35Cl]. Anal. Calcd. for C14H14ClNO: C, 67.88; H, 5.70; N, 5.65.
Found: C, 67.75; H, 5.91; N, 5.48.
N-Phenyl-N-[1-(2-thienyl)but-3-enyl]amine (4a). The
compound 4a was obtained in 88% yield, yellow oil. Its spectral
data were in agreement with those reported in literature [5].
N-(4-Chlorophenyl)-N-[1-(2-thienyl)but-3-enyl]amine (4b).
2-(Phenylamino)-2-(2-thienyl)acetonitrile
(6a).
The
compound 6a was obtained in 80% yield, yellow oil. 1H nmr
(deuterium chloroform): δ 7.26-7.23 (2H, m, 3,5-HThie), 7.16
1
The compound 4b was obtained in 57 % yield, yellow oil. H

930
L. Y. V. Méndez and V. V. Kouznetsov
Vol 45
(2H, t, J = 7.7 Hz, 3(5)-HPh), 6.92 (1H, t, J = 4.1 Hz, 4-HThie),
6.81 (1H, t, J = 7.3 Hz, 4-HPh), 6.67 (2H, d, J = 8.4 Hz, 2(6)-
HPh), 5.50 (1H, d, J = 8.1 Hz, HC-CN), 4.12 (1H, br.d, J = 8.3
Hz, H-N), 13C nmr (100 MHz): δ 144.0, 136.7, 129.5 (+),
127.1 (2C, +), 127.0 (2C, +), 120.6 (+), 117.5, 114.5 (2C, +),
46.0 (+). ms: m/z: 214 (molecular ion). Anal. Calcd. for
C12H10N2S: C, 67.26; H, 4.70; N, 13.07. Found: C, 67.38; H,
4.46; N, 13.33.
REFERENCES AND NOTES
[*] Fax
kouznet@uis.edu.co.
[1] Ochoa Puentes, C.; Kouznetsov, V. J. Heterocycl. Chem.
2002, 39, 595.
[2] Ding, H.; Friestad, G. K. Synthesis 2005, 2815.
[3] Vargas, M. L. Y.; Castelli, M. V.; Kouznetsov, V. V.;
5776-346149
or
90212-
2245013.
E-mail:
Urbina, G. J. M.; López, S.N.; Sortino, M.; Enriz, R. D.; Ribas, J. C.;
Zacchino, S.A. Bioorg. Med. Chem. 2003, 11, 1531.
2-(Phenylamino)-2-(3-thienyl)acetonitrile (6b). The
1
compound 6b was obtained in 84 % yield, yellow oil. H nmr
[4]
Kouznetsov, V. V.; Rivero Castro, J.; Ochoa Puentes, C.;
(deuterium chloroform): δ 7.42 (1H, t, J = 1.4 Hz, 2-HThie), 7.26
(1H, dd, J = 5.0, 3.0 Hz, 5-HThie), 7.13 (2H, t, J = 7.8 Hz, 3(5)-
HPh), 7.07 (1H, dd, J = 5.0, 1.0 Hz, 4-HThie), 6.76 (1H, t, J = 7.4
Hz, 4-HPh), 6.62 (2H, d, J = 8.0 Hz, 2(6)-HPh), 5.32 (1H, s, HC-
CN), 3.90 (1H, br.s, H-N), 13C nmr (75 MHz): δ 144.4, 134.5,
129.6 (2C, +), 127.8 (+), 126.1 (+), 124.3 (+), 120.4 (+), 118.2,
114.3 (2C, +), 46.0 (+). ms: m/z: 214 (molecular ion). Anal.
Calcd. for C12H10N2S: C, 67.26; H, 4.70; N, 13.07. Found: C,
67.45; H, 4.76; N, 12.98.
2-(4-Chlorophenylamino)-2-(3-thienyl)acetonitrile (6c).
The compound 6b was obtained in 88 % yield, yellow oil. 1H
nmr (deuterium chloroform): δ 7.42 (1H, dd, J = 2.8, 1.6 Hz,
2-HThie), 7.28 (1H, dd, J = 5.0, 3.0 Hz, 5-HThie), 7.11-7.05 (3H,
m, 4-HThie, and 3(5)-HAr), 6.56 (2H, d, J = 8.8 Hz, 2(6)-HAr),
5.28 (1H, d, J = 8.8 Hz, HC-CN), 3.98 (1H, d, J = 8.8 Hz, H-
N), 13C nmr (75 MHz): δ 143.0, 134.1, 129.5 (2C, +), 129.1,
127.9 (+), 126.0 (+), 125.3, 124.4 (+), 117.9, 115.5 (2C, +),
46.1 (+). ms: m/z: 248 (molecular ion). Anal. Calcd. for
C12H10ClN2S: C, 57.95; H, 3.65; N, 11.26. Found: C, 57.87;
H, 3.94; N, 11.32.
Stashenko, E. E.; René Martinez, J.; Ochoa, C.; Montoro Pereira, D.; Nogal
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Bahsas, A.; Amaro-Luis, J. Archiv der Pharmazie 2005, 338, 32.
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Y.; Zacchino, S. A.; Mora Cruz, U.; Enriz, R. D. Bioorg. Med. Chem.
2006, 14, 1851.
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Acknowledgments. VK thanks Industrial University of
Santander (UIS) for providing sabbatical year (2005-2006) and
Prof. José Barluenga and Prof. Miguel Tomas (Instituto
Universitario de Química Organometálica “Enrique Moles”,
Universidad de Oviedo) for their warm receive during the
realization of this sabbatical year. LYVM thanks
COLCIENCIAS for her fellowship.
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[19] These biological results will be published elsewhere.