Synthesis and biological evaluation of 2-oxonicotinonitriles and 2-oxonicotinonitrile based nucleoside analogues

Article abstract of DOI:10.1016/j.ejmech.2013.12.055

Drug resistance and emergence of new pathogens highlight the need for developing new therapeutic agents. We focused on 2-oxonicotinonitrile (2-ONN) as derivative of the natural product 2-pyridinone.¹ Herein, we describe the synthesis of 2-ONNs

Full text of DOI:10.1016/j.ejmech.2013.12.055

European Journal of Medicinal Chemistry 74 (2014) 388e397
Contents lists available at ScienceDirect
European Journal of Medicinal Chemistry
journal homepage: http://www.elsevier.com/locate/ejmech
Original article
Synthesis and biological evaluation of 2-oxonicotinonitriles and
2-oxonicotinonitrile based nucleoside analogues
*
**
Reham A.I. Abou-Elkhair , Ahmed H. Moustafa , Abdelfattah Z. Haikal,
Ahmed M. Ibraheem
Department of Chemistry, Faculty of Sciences, Zagazig University, Zagazig, Egypt
a r t i c l e i n f o
a b s t r a c t
Article history:
Drug resistance and emergence of new pathogens highlight the need for developing new therapeutic
agents. We focused on 2-oxonicotinonitrile (2-ONN) as derivative of the natural product 2-pyridinone.1
Herein, we describe the synthesis of 2-ONNs bearing two aryl groups, which we coupled with organo-
halides, including three glycosyl bromides, to prepare the nucleoside analogues. Coupling occurred
mostly at the 2-ONN ring nitrogen to give the aimed targets, and in a few cases, it happened at the 2-oxo
position giving O-alkylation products. Free 2-ONNs and their acetylated nucleosides were tested against
a number of viruses. The nucleoside analogue 2aAc showed good anti SARS-CoV and anti influenza A
(H5N1) activities. Additionally, 7b had good activity against Gram positive bacterium, Bacillis subtilis.
Ó 2014 Elsevier Masson SAS. All rights reserved.
Received 8 November 2013
Received in revised form
25 December 2013
Accepted 26 December 2013
Available online 8 January 2014
Keywords:
2-Oxonicotinonitrile
2-Pyridinone
Nucleoside analogues
Glycosylation
Antimicrobial
Antiviral
1. Introduction
Herein, we discuss the synthesis of three 2-ONN diaryl de-
rivatives (1aec, Fig. 1) for antiviral and antimicrobial activity
Drug resistance in microbial and viral infections has become a
marked problem causing the failure of many treatments. The con-
stant search for new drugs to be used alone or in combination with
existing market drugs has become a necessity. In continuation of
our efforts in finding such drug candidates, we have focused on the
investigation of 2-oxonicotinonitrile (2-ONN) derivatives contain-
ing two aryl groups at the four- and six- positions of the ring. The 2-
ONN ring contains the biologically important, naturally occurring
2-pyridinone motif [1,2]. This motif has been found in compounds
that are human immune deficiency virus 1 (HIV-1) nonnucleoside
reverse transcriptase inhibitors [3e5], anti-herpes simplex virus 1
(HSV-1) agents [6], hepatitis C virus (HCV) NS5B polymerase in-
hibitors [7], and anti-hepatitis B virus (HBV) agents [8]. In addition
to their antiviral activity, 2-pyridinone derivatives are known to
possess activity against wild type [9,10] and resistant [11] bacterial
strains. The derivatives have also been shown to be antifungal [12]
and antiprotozoal agents [13,14].
testing. For enhancing their potency as antiviral agents, our 2-ONN
compounds were coupled with different halo-sugars and halo-alkyl
derivatives, to make the corresponding nucleoside and acyclic
nucleoside analogues. Nucleoside analogues are well known to
exhibit potent antiviral activity [15].
2. Results and discussion
2.1. Chemistry
2-ONN derivatives 1aec (Fig. 1) were synthesized by one-pot
condensation [16,17] of ethyl cyanoacetate with the correspond-
ing aromatic ketone and aromatic aldehyde, in presence of
ammonium acetate in refluxing ethanol (see Scheme 1). The 2-ONN
ring was attached to 2-pyridyl (Py) and p-chlorophenyl (PhCl)
groups in 1a, to 2-thienyl (Th) and 4-isopropylphenyl (PhPr) groups
in 1b, and to two Th groups in 1c. Compounds 1a [18] and 1c [19]
were reported to be prepared through their respective chalcones
in two steps from the aldehyde and ketone. However, the one-pot
method that we adapted afforded a shorter route for their syn-
thesis. Compounds 1aec were obtained as the amido tautomer as
suggested by the presence of bands in the IR spectrum character-
istic for NH and C]O of the amide functional group. This was also
* Corresponding author. Tel.: þ20 1116714614.
** Corresponding author. Tel.: þ20 1067517333.
E-mail addresses: rabouelkhair@zu.edu.eg, riham31@yahoo.com (R.A.I. Abou-
Elkhair), ah_hu_mostafa@yahoo.com (A.H. Moustafa).
1
2-ONN: 2-oxonicotinonitrile.
0223-5234/$ e see front matter Ó 2014 Elsevier Masson SAS. All rights reserved.
http://dx.doi.org/10.1016/j.ejmech.2013.12.055

R.A.I. Abou-Elkhair et al. / European Journal of Medicinal Chemistry 74 (2014) 388e397
389
reaction conditions in a good yield to give, after deprotection, the
O-alkylation product 5 (entry 4). This was judged by the absence of
the IR band corresponding to the amide C]O functional group. The
coupling at the 2-oxo position of 1a was also seen with allyl bro-
mide and propargyl bromide to give the O-alkylation products 9
(entry 8) and 10 (entry 9), respectively.
Cl
S
CN
O
CN
O
CN
O
Based on the above results, only 1a among the three 2-ONN
compounds under study was glycosylated at the 2-oxo position
with a few simple organohalides. In all other cases coupling
occurred mainly at the ring N atom. In fact, these results were in
contrast to the ones we observed in our previous work [21,22],
where we have examined the coupling of the 2-ONN derivative 1d
(Fig. 2) with 10 different glycosyl and substituted alkyl halides
under the same reaction conditions. In all cases, alkylation occurred
at the 2-oxo position of the 2-ONN ring of 1d and the corresponding
O-glycosylation and O-alkylation products were separated in yields
ranging from 48% to 87%. Compounds 1aec differ from 1d by
changing one of the aryl groups attached to the 2-ONN ring, while
retaining the other one. Other published work showed that a very
close 2-ONN structure (1e, Fig. 2) is also glycosylated at the 2-oxo
position under the same conditions [23]. Furthermore, the similar
2-ONN compound 1f (Fig. 2) was also reported to couple with ethyl
bromoacetate at the 2-oxo position under similar reaction condi-
tion to the one used in our work [24].
Interestingly, reported results [25] showed that a compound
different from 1d, only in that the positions of the PhCl and Th
groups relative to the 2-ONN ring are interchanged, undergoes N-
glucosylation under similar reaction conditions to ours. Keeping
these contradicting results in mind, one can envision that regio-
selectivity of the reaction depends on the size of both the coupling
agent and the substituents on the 2-ONN ring. Additionally, the
type and relative positions of the aryl substituents on the ring
induce an electronic effect that contributes to the relative electron
density at the ring N and 2-oxo positions, which in turn controls the
regioselectivity. It is to be noted that careful chromatographic
separation of products of such reactions show that both N- and O-
glycosylation/alkylation can occur, with one of them as the major
product [26].
N
H
N
N
H
H
N
S
S
1a
1b
1c
Fig. 1. Structures of three synthesized 2-ONN derivatives.
emphasized by the presence of an 1H NMR peak at a chemical shift
higher than 12 ppm, corresponding to the amide NH. Obtaining the
amido tautomer rather than the imido was explained by a recent
study showing that the amido tautomer was more stable and hence
predominant [20].
Derivatives 1aec were coupled with different organohalides in
presence of K2CO3 in N,N-dimethylformamide (DMF) in order to
give the aimed nucleoside analogues (Table 1). A range of these
coupling agents were O-acetylated (Table 1, entries 1e6), in which
case the coupling reaction was followed by deacetylation with
triethylamine (TEA) in H2O/MeOH. Products before and after
deacetylation were separated by crystallization from ethanol for
biological evaluation. Structures of these separated coupling
products were confirmed by IR, NMR, and elemental analyses.
Table 1 shows the structure of the final products after deacetylation
and lists the yields for the coupling reaction itself.
Entries 1e3 of Table 1 show the synthesis of seven 2-ONN based
nucleoside analogues. Compounds 1aec were coupled with both
peracetylated
mides leading to the formation of the corresponding N-glycosides
2aec (entry 1) and 3aec (entry 2), respectively, after deacetylation.
Similarly, 1a was coupled with peracetylated
(entry 3) to give the respective N-lactoside (4) after deacetylation.
In all these seven cases, the acetylated N- -glycosides were ob-
a-D-glucopyranosyl and a-D-galactopyranosyl bro-
a-D-lactosyl bromide
b
tained in yields ranging from 51% to 87%, indicating that the
coupling reaction occurred mainly at the nitrogen of the 2-ONN
ring. Formation of the N-glycoside was confirmed by an IR band
in the range of 1640e1660 cm‾1 corresponding to an amide C]O
functional group for each compound. Those resulting nucleosides
2.2. Biology
2.2.1. Evaluation of antimicrobial activities
Our new 2-ONN derivatives were screened in vitro for anti-
bacterial activity against Bacillis subtilis and Escherichia coli,
representing Gram positive and Gram negative bacteria, respec-
tively, and antifungal activity against the fungi Aspergillus niger
and Aspergillus virdi-nutans. Zone of inhibition screening tests
based on well diffusion method were used to examine both the
antibacterial and antifungal activities. Table 2 shows the diam-
eter of inhibition zone in mm for the 2-ONN compounds against
the selected bacteria and fungi. The results were compared to
Ampicillin as a reference antibacterial drug and Dermatin as a
reference antifungal drug to evaluate the potency of the tested
compounds. This antimicrobial study was conducted for both the
final deprotected form and O-acetylated form of the 2-ONN de-
rivatives. As mentioned above, O-acetylated forms were origi-
nally obtained as synthetic intermediates. The latter were more
lipophilic and could have different biological properties than the
deacetylated counterparts. Derivatives in Table 2 that were var-
iants of 2-ONN compounds from Table 1 by acetyl protection
were denoted by the addition of Ac to the number of each
compound. Since the tested samples were prepared as N,N-
dimethylformamide (DMF) solutions, wells containing only the
microorganism and DMF were used as a negative control. DMF
resulted in no inhibition zone.
had b
-configuration as indicated by the 1H NMR coupling constant
of the anomeric proton (J > 7.5 Hz) due to diaxial coupling with
H-20.
Preparation of acyclic nucleoside analogues were attempted by
coupling our 2-ONNs with five different substituted alkyl halides.
Coupling with 3-hydroxypropyl chloride led to the N- alkylation, as
desired, to give 8aec in good yields (entry 7). The 2-ONN ring of
1aec reacted with 2-bromomethoxyethyl acetate at the nitrogen
atom as well to give the N- alkylation products 7a and 7b after
deprotection and the unprotected 7cAc (entry 6). However, when
1aec were coupled with 4-bromobutyl acetate, results varied. 1b
and 1c underwent N- alkylation to give 6b and 6c as the final and
major products, respectively (entry 5). On the other hand, 1a un-
derwent coupling at the 2-oxo position with the same reagent and
O
O
CH3CO2NH4
EtOH, reflux
+
+
1a-c
NC
CO2Et
Ar
Ar = Py or Th
Ar'
H
Ar' = PhCl, PhPr, or Th
Scheme 1. Preparation of 2-ONN derivatives 1aec.

390
R.A.I. Abou-Elkhair et al. / European Journal of Medicinal Chemistry 74 (2014) 388e397
Among the tested compounds, 7b showed the highest antibac-
analogues, in addition to uncoupled 2-ONN derivatives 1aec were
selected for this study. The compounds were evaluated for their
antiviral activity in comparison to known drugs for each virus as
controls. Antiviral activity was given as 50% effective concentration
terial activity (23 mm) against B. subtilis, which was even higher
than the standard drug Ampicillin (20 mm). However, it had no
activity against the Gram negative bacteria E. coli. In fact, all the
tested compounds except 3b showed no activity against E. coli. 3b
had small antibacterial activity of 5 mm compared to that of
Ampicillin (18 mm). Compounds 2b and 7cAc showed moderate
(EC50), which is the concentration of the compound in
to inhibit 50% of viral infection. Cytotoxic concentration (CC50) was
determined as the concentration of the compound in M at which
mM required
m
antibacterial activity against B. subtilis. Compounds 2bAc, 2cAc, 3aAc
,
50% of cells become dead. Selectivity index (SI) was calculated as
the ratio of CC50 to IC50 values, and was used along with the EC50
values to evaluate the bioactivity of 2-ONN derivatives.
3bAc, 2c, 3a, 3b, 3c, 5Ac, 5, 8a and 9 showed lower antibacterial
activity against Gram positive bacteria compared to Ampicillin.
These data proved that there was no obvious trend suggesting that
increasing lipophilicity by addition of acetyl groups in the 2-ONN
structure had an effect on the antibacterial activity. Antifungal
zone of inhibition studies showed that all the tested compounds
had moderate antifungal activity against Asperigillus niger and
Asperigillus virdi-nutans compared to the standard drug Dermatin.
Anti HCV and HBV activities were assessed using RNA replicon
and DNA virion control assays, respectively. Anti HBV activity was
compared to that of Lamivudine. Anti HSV-1 and HSV-2 as two
additional representatives of DNA virus families were compared to
acyclovir as the control drug. Similarly, anti HCV activity of the
compounds was compared to that of human interferon-alpha (HIA)
and 20C-methylcytidine (20C-MC). As summarized in Table 3 results
showed that among the tested compounds, 1c showed the best
2.2.2. In vitro antiviral screening
antiviral activity against HSV-1 and HSV-2 (EC50 > 12
2bAc, 2cAc and 3cAc were moderately active against HSV-1 and HSV-
2 with an EC50 of 67.2, >60, and >60 M, respectively. However, the
mM), while
A panel of different viral species was used to evaluate the in vitro
antiviral activity of some of the 2-ONN compounds in this report.
The panel consisted of HCV, HBV, HSV-1, HSV-2, severe acute res-
piratory syndrome coronavirus (SARS-CoV), West Nile virus (WNV),
influenza A virus (serotypes H3N2, H5N1 and H1N1) and influenza B
virus. The acetylated 2-ONN glucosides 2aAcecAc, and the acety-
lated galactoside of 1c (3cAc), which we designed as nucleoside
m
SI values are much lower than reference drugs. All tested com-
pounds were inactive against HCV and HBV as the EC50 values are
higher than 100
mM. Anti SARS-CoV and WNV activities were
investigated in comparison with M128533 and infergen, respectively
Table 1
Coupling of 2-ONN derivatives 1aec with different organohalides.
Entry
Deriv.a
Coupling agent
Producta,b
Ar'
% Yieldc
CN
AcO
O
1
1aec
2a: 66
2b: 58
2c: 62
Ar
Ar
N
O
AcO
AcO
Br
OAc
Glc
2a-c
Ar'
CN
O
OAc
AcO
O
2
1aec
3a: 87
3b: 70
3c: 51
N
Br
OAc
AcO
Gal
3a-c
PhCl
OAc
CN
O
OAc
O
AcO
3
1a
66
O
AcO
Py
N
O
OAc
Br
OAc
AcO
Lac
4
PhCl
CN
Br
4
5
1a
80
AcO
Py
Ar
N
O(CH2)4OH
5
Ar'
N
CN
O
Br
1b,c
6b: 57
6c: 53
AcO
(CH2)4OH
6b,c

R.A.I. Abou-Elkhair et al. / European Journal of Medicinal Chemistry 74 (2014) 388e397
391
Table 1 (continued )
Entry
Deriv.a
Coupling agent
Producta,b
% Yieldc
Ar'
CN
O
O
Br
d
6
1aec
7a: 76
7b: 62
7cAc: 45
AcO
Ar
Ar
N
CH2O(CH2)2OH
7a,b, 7cAc
Ar'
CN
7
1aec
8a: 74
8b: 88
8c: 82
HO
Cl
N
O
(CH2)3OH
8a-c
PhCl
CN
Br
Br
8
1a
1a
82
73
Py
Py
N
O
9
PhCl
CN
O
9
N
10
a
a: Ar ¼ Py; Ar0 ¼ PhCl, b: Ar ¼ Th; Ar0 ¼ PhPr, c: Ar ¼ Ar0 ¼ Th.
Glc: glucosyl, Gal: galactosyl, Lac: lactosyl.
Coupling yield before deprotection.
b
c
d
Coupling product was not deacetylated for 7cAc
.
as control drugs. Results were obtained using both visual and
neutral red tests. Among the tested compounds, only 2aAc was
slightly active by visual, but not neutral red test for SARS-CoV.
Anti influenza activity was screened using ribavirin as the
control drug. Cytopathic effect and cytotoxicity were used as con-
trol assays and the resulting data were reported in Table 4. The
screened compounds against influenza B virus showed that all
tested compounds were not active. On the other hand, 2aAc was
slightly active against H5N1 influenza A virus. The 2-ONN de-
rivatives were moderately active against H1N1 serotype.
bromosugars and other organohalides. Some attempts of the
coupling resulted in reaction at the 2-oxo position instead of the 2-
ONN ring nitrogen. Seemingly, a combination of steric and elec-
tronic factors had an effect on the regioselectivity of the coupling
reaction. Changing the coupling reaction conditions, such as the
type of the base used, could lead to different selectivity [24]. Among
the synthesized 2-ONN derivatives and their nucleosides, 7b
Table 2
Antibacterial and antifungal inhibitory activities of 2-ONN derivatives.
2-ONN derivative
(250 mg/disc)
Diameter of inhibition zone (mm)
3. Conclusion
Bacillus
subtilis
Escherichia
coli
Asperigillus
niger
Asperigillus
virdi-nutans
A series of 2-oxonicotinonitrile based analogues of nucleosides
and acyclic nucleosides were prepared by coupling 2-ONNs with
2bAc
2cAc
2b
1
2
0
0
7
8
7
6
8
10
2
0
0
7
8
2c
6
3aAc
3bAc
3a
1
1
2
0
0
0
7
9
7
5
6
7
Cl
Cl
3b
3
5
8
6
3c
4
0
8
8
5Ac
5
7cAc
7b
8a
9
DMF
Ampicillin
Dermatin
3
2
10
23
3
1
0
20
e
0
0
0
0
0
0
0
18
e
9
7
8
7
9
7
0
e
7
5
7
6
9
7
0
e
CN
CN
O
CN
O
N
O
N
N
H
H
H
S
N
Cl
1d
1e
1f
22
31
Fig. 2. Structures of 2-ONNs in the literature.

392
R.A.I. Abou-Elkhair et al. / European Journal of Medicinal Chemistry 74 (2014) 388e397
Table 3
Antiviral activity of compounds 1aec, 2aecAc, and 3cAc
.
a
a
a
2-ONN derivative
HCV EC50
HBV EC50
HSV-1
HSV-2
SARS-CoV
WNV EC50
a
a
a
EC50
SI
EC50
SI
EC50
SI
1a
1b
1c
2aAc
2bAc
2cAc
3cAc
HIA
>100
>100
>100
>100
>100
>100
>100
2
>100
>100
>100
>100
>100
>100
>100
e
>300
>300
>12
>300
67.2
>60
>60
e
1
1
>300
>300
>12
>300
60.3
>60
>60
e
1
1
>0.32
>26
>100
8.3
>100
>32
10
ND
ND
ND
4.3
ND
ND
1.9
e
>2.2
>2.2
>4.6
>5.1
>4.7
>3
<4.7
1
>4.4
<4
<2.4
e
<4.8
1
>4.9
<4
<2.4
e
>3.6
e
e
20C-MC
Lamivudine
Acyclovir
M128533
Infergen
1.6
e
e
e
e
e
e
e
e
e
0.035
e
e
e
e
e
e
e
e
e
3.3
e
>30.3
e
9.6
e
>10.4
e
e
e
e
e
e
0.59
e
>170
e
e
e
e
e
e
e
e
0.00004
a
EC50 is measured in mM.
showed good activity against the Gram positive bacterium B. sub-
tilis, and 2aAc was active against SARS-CoV and influenza A H5N1
virus. The 2-ONN compounds showed moderate antifungal activity.
4.2. Chemistry
4.2.1. General procedure for the preparation of 2-ONN 1aec
A mixture of the aromatic ketone (0.01 mol), the aromatic
aldehyde (0.01 mol), ethyl cyanoacetate (1.13 g, 0.01 mol), and
ammonium acetate (6.16 g, 0.08 mol) in ethanol (30 mL) was
refluxed for 12 h. After cooling, the precipitate was filtered off,
washed with ethanol, and dried. Recrystallization from DMF/
Ethanol (1:10 v:v) afforded the 2-ONN derivatives 1a-c.
4. Experimental results and protocols
4.1. Materials, instruments and general considerations
Starting materials and reagents were purchased from Aldrich
and had a minimum purity of 97%. DMF was dried by distillation
from CaCl2. 4-Bromobutyl acetate [27] and 2-bromom
ethoxyethyl acetate [28] were prepared according to literature
from tetrahydrofuran and 1,3-dioxane, respectively. Other sol-
vents and reagents were purchased from commercial sources and
used as received. Reaction progress was monitored by TLC anal-
ysis using aluminium-backed plates pre-coated with Merck silica
gel 60 F254. Spots separated on the TLC plates were visualized by
UV light and/or charring with a solution of 10% H2SO4 in EtOH.
Column chromatography was carried out on WhatmanÔ 60e120
mesh silica. Melting points were measured using an Electro-
thermal IA 9100 apparatus. IR spectra (KBr disc) were recorded
on either a Pye Unicam Sp-3-300 or a Shimadzu FTIR 8101 PC
infrared spectrophotometer. The 1H and 13C NMR spectra were
recorded on JEOL-JNM-LA 300 MHz spectrometer. Chemical
4.2.1.1. 4-(4-Chlorophenyl)-2-oxo-6-(2-pyridyl)nicotinonitrile (1a).
This compound was prepared from 2-acetylpyridine (1.21 g) and 4-
chlorobenzaldehyde (2.4 g) according to the general procedure
described above, and was obtained as a green powder (1.55 g, 50.4%
yield), mp 318e320 ꢁC (lit [18]. mp 209e214 ꢁC). IR (KBr, cm‾1):
3294 (NH), 2217 (C^N), 1655 (C]O, amide). 1H NMR (300 MHz,
DMSO-d6):
d
7.32 (s, 1H, AreH, 2-ONN ring), 7.59 (t, 1H, J ¼ 5.1 Hz,
AreH, Py), 7.68 (d, 2H, J ¼ 8.7 Hz, AreH), 7.78 (d, 2H, J ¼ 8.7 Hz, Are
H), 8.04 (t, 1H, J ¼ 7.5 Hz, AreH, Py), 8.30 (d, 1H, J ¼ 8.1 Hz, AreH,
Py), 8.77 (d, 1H, J ¼ 4.8 Hz, AreH, Py), 12.38 (br, 1H, NH). Anal. Calcd
for C17H10ClN3O (307.73): C, 66.35; H, 3.28; N, 13.65. Found: C,
66.34; H, 3.28; N, 13.66.
4.2.1.2. 4-(4-Isopropylphenyl)-2-oxo-6-(2-thienyl)nicotinonitrile
(1b). This compound was prepared from 2-acetylthiophene
(1.26 g) and 4-isopropylbenzaldehyde (1.48 g) according to the
general procedure described above, and was obtained as a yellow
powder (1.2 g, 38% yield), mp 310e311 ꢁC. IR (KBr, cm‾1): 3278
(NH), 2210 (C^N), 1636 (C]O, amide). 1H NMR (300 MHz, DMSO-
shifts (d) were reported in ppm and were referenced to tetra-
methylsilane as a standard (0.00 ppm). Chemical shifts for 13C
NMR were referenced relative to DMSO (39.50 ppm). Elemental
microanalysis was done on a Perkin Elmer 240 analyzer. Analyses
indicated by the symbols of the elements were within ꢀ0.4% of
the theoretical values.
d6):
d
1.24 (d, 6H, J ¼ 6.9 Hz, CH3(i-Pr)), 2.98 (m, 1H, CH (i-Pr)), 7.23
(s, 1H, 2-ONN ring), 7.29 (t, 1H, J ¼ 3.9 Hz, Th), 7.43 (d, 2H, J ¼ 8.1 Hz,
AreH), 7.64 (d, 2H, J ¼ 8.1 Hz, AreH), 7.87 (d,1H, J ¼ 5.1 Hz, Th), 8.06
(d, 1H, J ¼ 4.8 Hz, Th), 12.74 (br, 1H, NH). Anal. Calcd for C19H16N2OS
(320.41): C, 71.22; H, 5.03; N, 8.74. Found: C, 71.23; H, 5.04; N, 8.73.
Table 4
Anti influaza activity of 1aec, 2aecAc, and 3cAc
.
2-ONN
derivative
Type-B
Type-A
H3N2
H5N1
H1N1
4.2.1.3. 2-Oxo-4,6-di(2-thienyl)nicotinonitrile (1c). This compound
was prepared from 2-acetylthiophene (1.26 g) and thiophene-2-
carbaldehyde (1.12 g) according to the general procedure
described above, and was obtained as a yellow powder (1.2 g, 43%
yield), mp > 300 ꢁC (lit [19]. mp 318 ꢁC dec.) IR (KBr, cm‾1): 3273
(NH), 2208 (C^N), 1636 (C]O, amide). 1H NMR (300 MHz, DMSO-
a
a
a
a
EC50
SI
EC50
SI
EC50
SI
EC50
SI
1a
1b
1c
2aAc
2bAc
2cAc
3cAc
Ribavirin
>36
46
ND
>2.2
ND
ND
>2.2
1
>2.6
22
0
>100
32
>100
3.2
>0
>3.1
>0
1.3
1
>0
ND
>76
26
ND
32
ND
ND
ND
>28
10
>3.8
e
>4.5
>4.2
>4.2
>3
>2.5
ND
>100
>3.2
40
16
24
33
40
>32
2
>3.1
e
32
e
d6):
d
7.22 (s, 1H, 2-ONN ring), 7.26 (t, 1H, J ¼ 3.9 Hz, Th), 7.32 (t, 1H,
32
>12
2.4
>100
>19
4.2
e
ND
>130
ND
>32
J ¼ 3.9 Hz, Th), 7.88 (d, 1H, J ¼ 5.1 Hz, Th), 7.98 (m, 2H, Th), 8.07 (d,
1H, J ¼ 4.8 Hz, Th), 12.74 (br, 1H, NH). Anal. Calcd for C14H8N2OS2
(284.36): C, 59.13; H, 2.84; N, 9.85. Found: C, 59.12; H, 2.85; N, 9.86.
>160
a
EC50 is measured in mM.

R.A.I. Abou-Elkhair et al. / European Journal of Medicinal Chemistry 74 (2014) 388e397
393
4.2.2. General procedure for glycosylation and alkylation
8.03 (d, 1H, J ¼ 4.8 Hz, Th). 13C NMR (75 MHz, DMSO-d6):
d
20.12
The 2-ONN derivatives 1aec (0.010 mol) were stirred with po-
tassium carbonate (1.38 g, 0.010 mol) in dry DMF (15 mL) for 1 h,
followed by the addition of the appropriate peracetylated glycosyl
bromide (0.011 mol) or alkyl halide (0.010 mol) in portions. Except
for allyl and propargyl derivatives, the reaction mixture was stirred
at room temperature overnight, filtered to remove insoluble ma-
terials, and then the solvent was evaporated under reduced pres-
sure. For allyl and propargyl derivatives, the reaction mixture was
refluxed for 5 h after stirring overnight; and after cooling it was
filtered, and the filtrate was poured into ice-water to give the crude
product as a precipitate, which in turn was filtered off and dried.
The crude product obtained in all cases was purified by recrystal-
lization from 95% ethanol.
(CH3(i-Pr)), 20.25, 20.26, 20.28 and 20.30 (4CH3CO), 34.2 (CH(i-Pr)),
61.5 (C-60), 68.0 (C-40), 68.8 (C-30), 71.4 (C-20), 72.2 (C-50), 93.8 (C-
10), 115.2 (C^N), 118.2, 128.5, 129.8, 130.2, 130.8, 131.2, 132.2, 132.8,
134.5, 135.2, 142.2, 151.2 (AreC), 161.5, 168.0, 169.4, 170.2 and 170.6
(5 C]O). Anal. Calcd for C33H34N2O10S (650.70): C, 60.91; H, 5.27;
N, 4.31. Found: C, 60.92; H, 5.27; N, 4.30. This powder (6.6 g) was
deprotected according to the general procedure described for
deacetylation to give 2b as a yellow powder (4.58 g, 96% yield), mp
298e300 ꢁC. IR (KBr, cm‾1): 3391 (broad, 4OH), 2215 (C^N), 1644
(C]O, amide). 1H NMR (300 MHz, CDCl3/D2O):
d 1.26 (d, 6H,
J ¼ 6.9 Hz, CH3 (i-Pr)), 2.88 (m, 1H, CH (i-Pr)), 3.14 (m, 3H, H-30, H-60
and H-600), 3.890 (m, 3H, H-20, H-40 and H-50), 6.18 (d, 1H,
0
0
J1 ,2 ¼ 8.4 Hz, H-1 ), 7.27 (t, 1H, J ¼ 3.9 Hz, Th), 7.38 (d, 2H, J ¼ 8.1 Hz,
AreH), 7.51 (d, 2H, J ¼ 8.1 Hz, AreH), 7.62 (s, 1H, 2-ONN ring), 7.64
(d, 1H, J ¼ 5.1 Hz, Th), 8.21 (d, 1H, J ¼ 4.8 Hz, Th). Anal. Calcd for
4.2.3. General procedure for deacetylation
TEA (1 mL) was added to a solution of the acetylated compound
(0.01 mol) in MeOH (20 mL) and 3 drops of water. The mixture was
stirred overnight at room temperature, and then the solvent was
evaporated under reduced pressure. The residue was repeatedly co-
evaporated with MeOH until TEA was removed, and then purified
by crystallization from 95% ethanol.
C25H26N2O6S (482.55): C, 62.23; H, 5.43; N, 5.81. Found: C, 62.24; H,
5.44; N, 5.80.
4.2.4.3. 1-( -D-Glucopyranosyl)-2-oxo-4,6-di(2-thienyl)nicotinoni-
b
trile (2c). Compound 1c (2.8 g) was reacted with peracetylated
glucosyl bromide (4.1 g) according to the general procedure
described for glycosylation to give a green powder (3.78 g, 62%
yield), mp 225e226 ꢁC. IR (KBr, cm‾1): 2213 (C^N), 1748 (C]O,
4.2.4. Compounds prepared by glycosylation/alkylation followed by
deacetylation
acetoxy), 1639 (C]O, amide). 1H NMR (300 MHz, DMSO-d6):
d 1.84,
0
0
4.2.4.1. 4-(4-Chlorophenyl)-1-(
b
-D-glucopyranosyl)-2-oxo-6-(2-
1.98, 1.99 and 2.02 (4s, 12H, 4CH3CO), 4.05 (dd, 1H, J5 ,6 ¼ 40.06,
0
0
00
0
00
0
00
pyridyl)nicotinonitrile (2a). Compound 1a (3 g) was reacted with
peracetylated glucosyl bromide (3.2 g) according to the general
procedure described for glycosylation, to give a yellow powder
(4.2 g, 66% yield), mp 220e222 ꢁC. IR (KBr, cm‾1): 2225 (C^N),1747
(C]O, acetoxy), 1662 (C]O, amide). 1H NMR (300 MHz, DMSO-d6):
J6 ,6 ¼ 12.2 Hz, H-6 ), 4.17 (dd, 1H, J5 ,6 ¼ 4.9, J6 ,6 ¼ 12.2 Hz, H-6 ),
4.35 (m, 1H, H-50), 5.03 (t, 1H, J3 ,4 ¼ 9.4 Hz, H-40), 5.23 (t, 1H,
0
0
J1 ,2 ¼ 8.4 Hz, H-20), 5.65 (t, 1H, J2 ,3 ¼ 9.0, J3 ,4 ¼ 9.6 Hz, H-30), 6.43
0
0
0
0
0
0
(d, 1H, J1 ,2 ¼ 8.7 Hz, H-10), 7.25 (t, 1H, J ¼ 3.9 Hz, Th), 7.31 (t. 1H,
J ¼ 3.9 Hz, Th), 7.52 (s, 1H, 2-ONN ring), 7.87 (d, 1H, J ¼ 5.2 Hz, Th),
7.98 (m, 2H, Th), 8.05 (d, 1H, J ¼ 4.8 Hz, Th). Anal. Calcd for
0
0
d
1.78, 1.94, 1.99 and 2.03 (4s, 12H, 4CH3CO), 4.08 (dd, 1H,
J5 ,6 ¼ 4.67, J6 ,6 ¼ 12.22 Hz, H-60), 4.22 (dd, 1H, J5 ,6 ¼ 4.9,
C
28H26N2O10S2 (614.64): C, 54.71; H, 4.26; N, 4.56. Found: C, 54.72;
0
0
0
00
0
00
J6 ,6 ¼ 12.2 Hz, H-600), 4.39 (m, 1H, H-50), 5.07 (t, 1H, J3 ,4 ¼ 9.4 Hz,
H, 4.25; N, 4.55. This powder (6.1 g) was deprotected according to
the general procedure described for deacetylation to give 2c as a
green powder (4.41 g, 91.4% yield), mp 300e302 ꢁC. IR (KBr, cm‾1):
3360 (broad, 4OH), 2216 (C^N), 1640 (C]O, amide). 1H NMR
0
00
0
0
H-40), 5.23 (t, 1H, J1 ,2 ¼ 8.2, J2 ,3 ¼ 9.6 Hz, H-20), 5.63 (t, 1H,
0
0
0
0
J2 ,3 ¼ 9.6, J3 ,4 ¼ 9.3 Hz, H-30), 6.72 (d, 1H, J1 ,2 ¼ 8.1 Hz, H-10), 7.32
(s, 1H, Py), 7.59 (t, 1H, J ¼ 5.1 Hz, Py), 7.68 (d, 2H, J ¼ 8.7 Hz, AreH),
7.78 (d, 2H, J ¼ 8.7 Hz, AreH), 8.05 (t, 1H, J ¼ 7.5 Hz, Py), 8.25 (d, 1H,
J ¼ 8.1 Hz, Py) 8.64 (d, 1H, J ¼ 4.8 Hz, Py). Anal. Calcd for
0
0
0
0
0
0
(300 MHz, DMSO-d6/D2O): d
3.36e3.40 (m, 6H, H-60, H-600, H-50, H-
40, H-30 and H-20), 5.98 (d, 1H, J1 ,2 ¼ 8.4 Hz, H-10), 7.23 (t, 1H,
J ¼ 3.9 Hz, Th), 7.29 (d, 1H, J ¼ 5.2 Hz, Th), 7.65 (s, 1H, 2-ONN ring),
7.82 (d, 1H, J ¼ 5.2 Hz, Th), 7.94 (m, 2H, Th), 7.98 (d, 1H, J ¼ 4.8 Hz,
Th). Anal. Calcd for C20H18N2O6S2 (446.50): C, 53.80; H, 4.06; N,
6.27. Found: C, 53.81; H, 4.08; N, 6.26.
0
0
C
31H28ClN3O10 (638.02): C, 58.36; H, 4.42; N, 6.59. Found: C, 58.34;
H, 4.43; N, 6.58. This powder (6 g) was deprotected according to the
general procedure described for deacetylation, to give 2a as a grey
powder (3.4 g, 88% yield), mp 300e302 ꢁC. IR (KBr, cm‾1): 3394
(broad, 4OH), 2223 (C^N), 1660 (C]O, amide). 1H NMR (300 MHz,
DMSO-d6/D2O):
d
3.24e3.63 (m, 6H, H-60, H-600, H-50, H-40, H-30, and
4.2.4.4. 4-(4-Chlorophenyl)-1-(b-D-galactopyranosyl)-2-oxo-6-(2-
H-20), 6.13 (d, 1H, J1 ,2 ¼ 8.4 Hz, H-10), 7.23 (s, 1H, 2-ONN ring), 7.43
(t, 1H, J ¼ 5.1 Hz, Py), 7.60 (d, 2H, J ¼ 8.7 Hz, AreH), 7.65 (d, 2H,
J ¼ 8.7 Hz, AreH), 7.95 (t, 1H, J ¼ 7.5 Hz, Py), 8.23 (d, 1H, J ¼ 8.1 Hz,
Py), 8.68 (d, 1H, J ¼ 4.8 Hz, Py). Anal. Calcd for C23H20ClN3O6
(469.87): C, 58.79; H, 4.29; N. 8.94. Found: C, 58.78; H, 4.29; N, 8.93.
pyridyl)nicotinonitrile (3a). Compound 1a (3.07 g) was reacted with
peracetylated galactosyl bromide (4.1 g) according to the general
procedure described for glycosylation a pale yellow powder (5.59 g,
87% yield), mp 184e186 ꢁC. IR (KBr, cm‾1): 2229 (C^N),1753 (C]O,
0
0
acetoxy), 1650 (C]O, amide). 1H NMR (300 MHz, DMSO-d6):
d 1.63,
0
0
1.84, 1.87 and 2.05 (4s, 12H, 4CH3CO), 3.87 (dd, 1H, J5 ,6 ¼ 6.0,
J6 ,6 ¼ 11.1 Hz, H-60), 4.01 (dd, 1H, J5 ,6 ¼ 6.3, J6 ,6 ¼ 11.1 Hz, H-600),
0
00
0
0
0
00
4.2.4.2. 1-(b-D-Glucopyranosyl)-4-(4-isopropylphenyl)-2-oxo-6-(2-
0
0
0
0
thienyl)nicotinonitrile (2b). Compound 1b (3.2 g) was reacted with
peracetylated glucosyl bromide (4.1 g) according to the general
procedure described for glycosylation to give a yellow powder
(3.78 g, 58% yield), mp 225e227 ꢁC. IR (KBr, cm‾1): 2215 (C^N),
1744 (C]O, acetoxy), 1643 (C]O, amide). 1H NMR (300 MHz,
4.56 (m, 1H, H-50), 5.23 (t, 1H, J3 ,2 ¼ 10.2, J3 ,4 ¼ 2.8 Hz, H-30), 5.38
(t, 1H, J2 ,1 ¼ 8.4, J2 ,3 ¼ 10.3 Hz, H-20), 5.43 (t, 1H, J4 ,3 ¼ 2.8,
0
0
0
0
0
0
J4 ,5 ¼ 2.7 Hz, H-40), 6.51 (d, 1H, J1 ,2 ¼ 8.4 Hz, H-10), 7.33 (s,1H, 2-
ONN ring), 7.43 (t, 1H, J ¼ 5.1 Hz, Py), 7.53 (d, 2H, J ¼ 8.7 Hz, Are
H), 7.64 (d, 2H, J ¼ 8.7 Hz, AreH), 7.90 (t, 1H, J ¼ 7.5 Hz, Py), 8.12 (d,
1H, J ¼ 8.1 Hz, Py), 8.45 (d, 1H, J ¼ 4.8 Hz, Py). 13C NMR (75 MHz,
0
0
0
0
DMSO-d6):
d
1.24 (d, 6H, J ¼ 6.9 Hz, CH3 (i-Pr)), 1.78, 1.85, 1.98 and
2.03 (4s, 12H, 4CH3CO), 2.98 (m, 1H, CH (i-Pr)), 4.09 (dd, 1H,
DMSO-d6): d
20.78, 20.84, 20.89 and 20.91 (4CH3CO), 62.1 (C-60),
J5 ,6 ¼ 4.7, J6 ,6 ¼ 12.2 Hz, H-60), 4.33 (dd, 1H, J5 ,6 ¼ 4.9,
68.06 (C-40), 68.15 (C-20), 70.66 (C-30), 71.72 (C-50), 94.64 (C-10),
114.4, 115.8 (C^N), 122.6, 126.3, 129.4, 130.6, 130.9, 134.8, 135.8,
138.1, 150.2, 153.1, 156.2, 156.4 (AreC), 162.3, 169.4, 170.0, 170.3 and
170.5 (5 C]O). Anal. Calcd for C31H28ClN3O10 (638.02): C, 58.36; H,
4.42; N, 6.59. Found: C, 58.35; H, 4.43; N, 6.58. This powder (6.3 g)
was deprotected according to the general procedure described for
0
0
0
00
0
00
J6 ,6 ¼ 12.2 Hz, H-600), 4.33 (m, 1H, H-50), 5.03 (t, 1H, J3 ,4 ¼ 9.4, H-
0
00
0
0
40), 5.20 (t, 1H, J1 ,2 ¼ 8.2, J2 ,3 ¼ 9.6 Hz, H-2 ), 5.62 (t, 1H, J2 ,3 ¼ 9.6,
0
0
0
0
0
0
0
J3 ,4 ¼ 9.0 Hz, H-30), 6.42 (d, 1H, J ¼ 8.7 Hz, H-10), 7.23 (t, 1H,
J ¼ 3.9 Hz, Th), 7.42 (d, 2H, J ¼ 8.1 Hz, AreH) 7.56 (s, 1H, 2-ONN
ring), 7.62 (d, 2H, J ¼ 8.1 Hz, AreH), 7.84 (d, 1H, J ¼ 5.1 Hz, Th),
0
0

394
R.A.I. Abou-Elkhair et al. / European Journal of Medicinal Chemistry 74 (2014) 388e397
deacetylation to give 3a as a yellow powder (4 g, 91% yield), mp
230e232 ꢁC. IR (KBr, cm‾1): 3416 (broad, 4OH), 2220 (C^N), 1659
4OH), 2218 (C^N), 1645 (C]O, amide). 1H NMR (300 MHz, DMSO-
d6/D2O):
d
3.47e3.78 (m, 6H, H-60, H-600, H-50, H-40, H-30 and H-20),
(C]O, amide). 1H NMR (300 MHz, DMSO-d6/D2O):
d
3.55 (m, 3H, H-
5.95 (d, 1H, J1 ,2 ¼ 8.4 Hz, H-10), 7.23 (t, 1H, J ¼ 3.9 Hz, Th), 7.31 (d,
1H, J ¼ 5.2 Hz, Th), 7.56 (s, 1H, 2-ONN ring), 7.81 (d, 1H, J ¼ 5.1 Hz,
Th), 7.93 (m, 2H, Th), 8.07 (d, 1H, J ¼ 4.8 Hz, Th). Anal. Calcd for
0
0
30, H-60 and H-600), 3.83 (m, 3H, H-20, H-40 and H-50), 6.09 (d, 1H,
J1 ,2 ¼ 7.8 Hz, H-10), 7.23 (s, 1H, 2-ONN ring), 7.53 (t, 1H, J ¼ 5.1 Hz,
Py), 7.62 (d, 2H, J ¼ 8.7 Hz, AreH), 7.71 (d, 2H, J ¼ 8.7 Hz, AreH), 7.99
(t, 1H, J ¼ 7.5 Hz, Py), 8.41 (d, 1H, J ¼ 8.1 Hz, Py), 8.70 (d, 1H,
J ¼ 4.8 Hz, Py). Anal. Calcd for C23H20ClN3O6 (469.87): C, 58.79; H,
4.29; N, 8.94. Found: C, 58.79; H, 4.28; N, 8.93.
0
0
C20H18N2O6S2 (446.50): C, 53.80; H, 4.06; N, 6.27. Found: C, 53.82;
H, 4.04; N, 6.26.
0
4.2.4.7. 4-(4-Chlorophenyl)-1-[O4 -(
b
-D-galactopyranosyl)-b-D-glu-
copyranosyl]-2-oxo-6-(2-pyridyl)nicotinonitrile (4). Compound 1a
(3.07 g) was reacted with peracetylated O4-(
-D-galactopyranosyl)-
-D-glucopyranosyl bromide (7.2 g) according to the general pro-
4.2.4.5. 1-(
b
-D-Galactopyranosyl)-4-(4-isopropylphenyl)-2-oxo-6-
b
(2-thienyl)nicotinonitrile (3b). Compound 1b (3.2 g) was reacted
with peracetylated galactosyl bromide (4.1 g) according to the
general procedure described for glycosylation to give a yellow
powder (4.58 g, 70% yield), mp 160e161 ꢁC. IR (KBr, cm‾1): 2218
(C^N), 1754 (C]O, acetoxy), 1644 (C]O, amide). 1H NMR
b
cedure described for glycosylation to give a yellow powder (5.2 g,
66% yield), mp 220e221 ꢁC. IR (KBr, cm‾1): 2223 (C^N),1747 (C]O,
acetoxy), 1662 (C]O, amide). 1H NMR (300 MHz, DMSO-d6):
d
1.77,
1.86, 1.87, 1.89, 1.90, 1.98 and 2.05 (7s, 21H, 7CH3CO), 3.87 - 4.01 (m,
00
0
(300 MHz, DMSO-d6):
d
1.23 (d, 6H, J ¼ 6.9 Hz, CH3 (i-Pr)), 1.63, 1.84,
3H, H-20b, H-60a and H-60b), 4.14 (dd, 1H, J6 a,6 a
¼
11.4,
00
00
0
1.88 and 2.04 (4s, 12H, 4CH3CO), 2.88 (m, 1H, CH (i-Pr)), 3.87 (dd,
J6 a,5 a ¼ 5.6 Hz, H-6 a), 4.36 (m, 1H, H-50b), 4.68 (dd, 1H,
1H, J5 ,6 ¼ 6.0, J6 ,6 ¼ 11.1 Hz, H-60), 4.01 (dd, 1H, J5 ,6 ¼ 6.3,
J6 b,5 b ¼ 6.3 Hz, H-600b), 4.87 (m, 1H, H-50a), 4.95 (dd, 1H,
0
0
0
00
0
0
00
0
J6 ,6 ¼ 11.1 Hz, H-600), 4.43 (m, 1H, H-50), 5.19 (t, 1H, J3 ,2 ¼ 10.2,
J1 b,2 b ¼ 7.6 Hz, H-10b), 5.04 (dd, 1H, J4 b,3 b ¼ 3.1, J4 b,5 b ¼ 3.8 Hz, H-
0
00
0
0
0
0
0
0
0
0
0
0
40b), 5.21 (dd, 1H, J2 a,1 a ¼ 8.7, J2 a,3 a ¼ 8.4 Hz, H-20a), 5.27 (dd, 1H,
0
0
0
0
0
0
0
0
0
0
J3 ,4 ¼ 2.8 Hz, H-3 ), 5.26 (t, 1H, J2 ,1 ¼08.4, J2 ,3 ¼ 10.3 Hz, H-2 ), 5.44
J4 a,3 a ¼ 9.1, J4 a,5 a ¼ 9.9 Hz, H-40a), 5.30 (d, 1H, J3 b,4 b ¼ 3.1 Hz, H-
0
0
0
0
0
0
0
0
0
0
0
0
(t, 1H, J4 ,3 ¼ 2.80, J4 ,5 ¼ 2.78 Hz, H-4 ), 6.26 (d, 1H, J1 ,2 ¼ 8.4 Hz, H-
10), 7.30 (t, 1H, J ¼ 3.9 Hz, Th), 7.48 (d, 2H, J ¼ 8.1 Hz, AreH) 7.50 (s,
1H, 2-ONN ring), 7.54 (d, 2H, J ¼ 8.1 Hz, AreH), 7.76 (d, 1H,
J ¼ 5.1 Hz, Th), 8.01 (d, 1H, J ¼ 4.8 Hz, Th). 13C NMR (75 MHz, DMSO-
30b), 5.38 (dd, 1H, J3 a,2 a ¼ 8.4, J3 a,4 a ¼ 9.1 Hz, H-30a), 6.54 (d, 1H,
0
0
0
0
J1 a,2 a ¼ 8.7 Hz, H-10a), 7.23 (s, 1H, 2-ONN ring), 7.42 (t, 1H,
J ¼ 5.1 Hz, Py), 7.60 (d, 2H, J ¼ 8.7 Hz, AreH), 7.66 (d, 2H, J ¼ 8.7 Hz,
AreH), 7.93 (t, 1H, J ¼ 7.5 Hz, Py), 8.49 (d, 1H, J ¼ 8.1 Hz, Py), 8.61 (d,
1H, J ¼ 4.8 Hz, Py). Anal. Calcd for C43H44ClN3O18 (926.27): C, 55.76;
H, 4.79; N, 4.54. Found: C, 55.77; H, 4.78; N, 4.55. This powder
(9.2 g) was deprotected according to the general procedure
described for deacetylation to give 4 as a yellow powder (4.8 g, 75%
yield), mp 275e277 ꢁC. IR (KBr, cm‾1): 3410 (broad, 7OH), 2220
(C^N), 1655 (C]O, amide). 1H NMR (300 MHz, DMSO-d6/D2O):
0
0
d6):
d 20.12 (CH3 (i-Pr)), 20.84, 20.85, 20.87 and 20.94 (4CH3CO),
33.82 (CH (i-Pr)), 61.9 (C-60), 68.03 (C-40), 68.24 (C-20), 70.60 (C-30),
71.81 (C-50), 94.7 (C-10), 114.2,115.6 (C^N),127.3,128.7, 129.1, 129.6,
132.1, 133.4, 142.5, 151.3, 153.1, 154.2, 157.1 (AreC), 162.2, 169.4,
169.9, 170.3 and 170.5 (5 C]O). Anal. Calcd for C33H34N2O10
S
(650.70): C, 60.91; H, 5.27; N, 4.31. Found: C, 60.90; H, 5.28; N, 4.32.
This powder (6.5 g) was deprotected according to the general
procedure described for deacetylation to give 3b as a yellow pow-
der (1.56 g, 85.5% yield), mp 220e222 ꢁC. IR (KBr, cm‾1): 3418
(broad, 4OH), 2216 (C^N), 1642 (C]O, amide). 1H NMR (300 MHz,
d
3.40e3.76 (4m, 12H, H-20b, H-30b, H-40b, H-50b, H-60b, H-600b, H-
20a, H-30a, H-40a, H-50a, H-60a and H-600a), 5.81 (d, 1H,
J1 b,2 b ¼ 7.8 Hz, H-10b), 5.92 (d, 1H, J1 a,2 a ¼ 8.9 Hz, H-10a), 7.24 (s,
1H, 2-ONN ring), 7.43 (t, 1H, J ¼ 5.1 Hz, Py), 7.62 (d, 2H, J ¼ 8.7 Hz,
AreH), 7.68 (d, 2H, J ¼ 8.7 Hz, AreH), 7.92 (t, 1H, J ¼ 7.5 Hz, Py), 8.48
(d, 1H, J ¼ 8.1 Hz, Py), 8.60 (d, 1H, J ¼ 4.8 Hz, Py). Anal. Calcd for
0
0
0
0
DMSO-d6/D2O):
d
1.21 (d, 6H, J ¼ 6.9 Hz, CH3 (i-Pr)), 2.93 (m, 1H, CH
(i-Pr)), 3.34e3.48 (m, 3H, H-30, H-60 and H-600), 3.52e3.61 (m, 3H,
H-20, H-40 and H-50), 5.92 (d, 1H, J1 ,2 ¼ 8.1 Hz, H-10), 7.19 (t, 1H,
J ¼ 3.9 Hz, Th), 7.41 (d, 2H, J ¼ 8.1 Hz, AreH), 7.62 (d, 2H, J ¼ 8.1 Hz,
AreH), 7.66 (s, 1H, 2-ONN ring), 7.73 (d, 1H, J ¼ 5.1 Hz, Th), 7.99 (d,
1H, J ¼ 4.8 Hz, Th). Anal. Calcd for C25H26N2O6S (482.55): C, 62.23;
H, 5.43; N, 5.81. Found: C, 62.24; H, 5.43; N, 5.82.
0
0
C
29H30ClN3O11 (632.01): C, 55.11; H, 4.78; N, 6.65. Found: C, 55.12;
H, 4.77; N, 6.65.
4.2.4.8. 4-(4-Chlorolphenyl)-2-(4-hydroxybutyloxy)-6-(2-pyridyl)
nicotinonitrile (5). Compound 1a (3.07 g) was reacted with 4-
bromobutyl acetate (1.95 g) according to the general procedure
described for alkylation to give a green powder (3.4 g, 80% yield),
mp 130e132 ꢁC. IR (KBr, cm‾1): 2220 (C^N), 1739 (C]O, acetoxy).
4.2.4.6. 1-(b-D-Galactopyranosyl)-2-oxo-4,6-di(2-thienyl)-nic-
otinonitrile (3c). Compound 1c (2.8 g) was reacted with peracety-
lated galactosyl bromide (4.1 g) according to the general procedure
described for glycosylation to give a colourless solid (3.05 g, 51%
yield), mp 210e212 ꢁC. IR (KBr, cm‾1): 2221 (C^N), 1745 (C]O,
1H NMR (300 MHz, DMSO-d6):
d 1.83 (m, 2H, CH2), 1.99 (s, 3H,
CH3CO), 2.94 (m, 2H, CH2),, 4.08 (t, 2H, J ¼ 5.7 Hz, CH2), 4.64 (t, 2H,
J ¼ 6.3 Hz, CH2), 7.43 (t, 1H, J ¼ 5.1 Hz, Py), 7.65 (d, 2H, J ¼ 8.7 Hz,
AreH), 7.78 (d, 2H, J ¼ 8.7 Hz, AreH), 8.10 (s, 1H, 2-ONN ring), 8.12
(t, 1H, J ¼ 7.5 Hz, Py), 8.43 (d, 1H, J ¼ 8.1 Hz, Py), 8.60 (d, 1H,
acetoxy), 1634 (C]O, amide). 1H NMR (300 MHz, DMSO-d6):
d 1.69,
0
0
1.82., 1.88 and 2.04 (4s, 12H, 4CH3CO), 3.91 (dd, 1H, J5 ,6 ¼ 60.00,
J6 ,6 ¼ 10.1 Hz, H-60), 3.99 (dd, 1H, J5 ,6 ¼ 6.3, J6 ,6 ¼ 10.1 Hz,0H-6 ),
0
00
0
0
0
00
4.44 (m, 1H, H-50), 5.21 (t, 1H, J3 ,2 ¼ 10.23, J3 ,4 ¼ 2.8 Hz, H-3 ), 5.28
J ¼ 4.8 Hz, Py). 13C NMR (75 MHz, DMSO-d6):
d
20.65 (CH3CO), 24.75
0
0
0
0
(t, 1H, J2 ,1 ¼ 8.4, J2 ,3 ¼ 10.3 Hz, H-20), 5.43 (t, 01H, J4 ,3 ¼ 2.8,
(CH2), 24.87 (CH2), 63.42 (CH2), 66.85 (CH2), 93.85, 113.4, 114.8
(C^N), 121.6, 125.4, 128.9, 130.1, 134.4, 135.0, 137.5, 149.5, 152.9,
154.9, 156.0, 163.9 and 170.2 (AreC, C]N and C]O). Anal. Calcd for
0
0
0
0
0
0
J4 ,5 ¼ 2.78 Hz, H-40), 6.23 (d, 1H, J1 ,2 ¼ 8.4 Hz, H-1 ), 7.20 (s, 1H, 2-
ONN ring), 7.24 (t, 1H, J ¼ 3.9 Hz, Th), 7.29 (t, 1H, J ¼ 5.2 Hz, Th), 7.82
(d, 1H, J ¼ 5.2 Hz, Th), 7.86 (m, 2H, Th), 8.05 (d, 1H, J ¼ 4.8 Hz, Th).
0
0
0
0
C23H20ClN3O3 (421.88): C, 65.48; H, 4.78; N, 9.96. Found: C, 65.47;
13C NMR (75 MHz, DMSO-d6):
d
20.84, 20.85, 20.88 and 20.93
H, 4.79; N, 9.98. This powder (4.21 g) was deprotected according to
the general procedure described for deacetylation to give 5 as a
yellow powder (2.6 g, 86% yield), mp 145e146 ꢁC. IR (KBr, cm‾1):
3418 (broad, OH), 2221 (C^N). 1H NMR (300 MHz, DMSO-d6):
(4CH3CO), 61.9 (C-60), 68.06 (C-40), 68.23 (C-20), 70.59 (C-30), 71.82
(C-50), 94.79 (C-10), 112.5, 115.6 (C^N), 129.1, 129.6, 129.7, 131.1,
131.7, 132.3, 132.5, 136.6, 142.3, 148.7 and 153.2 (AreC), 162.7, 169.4,
169.9, 170.3 and 170.5 (5 C]O). Anal. Calcd for C28H26N2O10S2
(614.64): C, 54.71; H, 4.26; N, 4.56. Found: C, 54.72; H, 4.26; N, 4.57.
This solid (6.14 g) was deprotected according to the general pro-
cedure described for deacetylation to give 3c as a yellow powder
(3.96 g, 89% yield), mp 245e246 ꢁC. IR (KBr, cm‾1): 3420 (broad,
d
1.63 (m, 2H, CH2), 1.87 (m, 2H, CH2), 3.28 (t, 1H, J ¼ 4.5 Hz, OH),
3.48 (t, 2H, J ¼ 5.7 Hz, CH2), 4.62 (t, 2H, J ¼ 6.3 Hz, CH2), 7.53 (t, 1H,
J ¼ 5.1 Hz, Py), 7.68 (d, 2H, J ¼ 8.7 Hz, AreH), 7.77 (d, 2H, J ¼ 8.7 Hz,
AreH), 8.0 (t,1H, J ¼ 7.5 Hz, Py), 8.12 (s, 1H, 2-ONN ring), 8.43 (d,1H,
J ¼ 8.1 Hz, Py), 8.74 (d, 1H, J ¼ 4.8 Hz, Py). Anal. Calcd for

R.A.I. Abou-Elkhair et al. / European Journal of Medicinal Chemistry 74 (2014) 388e397
395
C21H18ClN3O2 (379.84): C, 66.40; H, 4.78; N, 11.06. Found: C, 66.41;
H, 4.78; N, 11.08.
8.72 (d, 1H, J ¼ 4.8 Hz, Py). Anal. Calcd for C20H16ClN3O3 (381.81): C,
62.91; H, 4.22; N, 11.01. Found: C, 62.92; H, 4.23; N, 11.00.
4.2.4.12. 1-[(2-Hydroxyethoxy)methyl]-4-(4-isopropylphenyl)-2-oxo-
6-(2-thienyl)nicotinonitrile (7b). Compound 1b (3.2 g) was reacted
with 2-bromomethoxyethyl acetate (1.97 g) according to the gen-
eral procedure described for alkylation to give a yellow powder
(3.3 g, 62% yield), mp 180e182 ꢁC. IR (KBr, cm‾1): 2218 (C^N), 1735
(C]O, acetoxy), 1643 (C]O, amide). 1H NMR (300 MHz, DMSO-d6):
4.2.4.9. 1-(4-Hydroxybutyl)-4-(4-isopropylphenyl)-2-oxo-6-(2-
thienyl)nicotinonitrile (6b). Compound 1b (3.2 g) was reacted with
4-bromobutyl acetate (1.95 g) according to the general procedure
for alkylation to give a yellow powder (2.55 g, 57% yield), mp 240e
242 ꢁC. IR (KBr, cm‾1): 2221 (C^N), 1731 (C]O, acetoxy), 1643 (C]
O, amide). 1H NMR (300 MHz, DMSO-d6):
d
1.25 (d, 6H, J ¼ 6.9 Hz,
d
1.24 (d, 6H, J ¼ 6.9 Hz, CH3 (i-Pr)), 2.02 (s, 3H, CH3CO), 2.97 (m, 1H,
CH3 (i-Pr)), 1.84 (m, 2H, CH2), 1.99 (s, 3H, CH3CO), 2.94 (m, 2H, CH2),
3.10 (m, 1H, CH (i-Pr)), 4.09 (t, 2H, J ¼ 5.7 Hz, CH2), 4.53 (t, 2H,
J ¼ 6.3 Hz, CH2), 7.21 (t, 1H, J ¼ 3.9 Hz, Th), 7.43 (d, 2H, J ¼ 8.1 Hz,
AreH), 7.62 (d, 2H, J ¼ 8.1 Hz, AreH), 7.76 (s, 1H, 2-ONN ring), 7.81
(d, 1H, J ¼ 5.1 Hz Hz, Th), 8.09 (d, 1H, J ¼ 4.8 Hz, Th). Anal. Calcd for
CH (i-Pr)), 3.34 (t, 2H, J ¼ 5.4 Hz, OCH2 (c)), 4.45 (t, 2H, J ¼ 5.4 Hz,
OCH2 (d)), 4.72 (s, 2H, NCH2O (a)), 7.22 (t,1H, J ¼ 3.9 Hz, Th), 7.43 (d,
2H, J ¼ 8.1 Hz, AreH), 7.62 (d, 2H, J ¼ 8.1 Hz, AreH), 7.79 (s, 1H, 2-
ONN ring), 7.82 (d, 1H, J ¼ 5.1, Hz, Th), 8.11 (d, 1H, J ¼ 4.8 Hz, Th). 13
C
NMR (75 MHz, DMSO-d6):
d 20.6 (CH3CO), 23.6 ( CH3 (i-Pr)), 33.3
C
25H26N2O3S (434.55): C, 69.10; H, 6.03; N, 6.45. Found: C, 69.11; H,
(CH (i-Pr)), 61.9 (CH2O (d)), 65.1 (OCH2 (c)), 91.2 (NCH2O), 112.2,
115.2 (C^N), 126.7, 128.2, 128.6, 129.0, 131.2, 133.0, 133.4, 142.4,
150.6, 152.5, 156.2 (AreC) and 163.6, 170.3 (2C ¼ O). Anal. Calcd for
6.02; N, 6.45. This powder (4.34 g) was deprotected according to
the general procedure described for deacetylation to give 6b as a
yellow powder (3.5 g, 92% yield), mp 260e262 ꢁC. IR (KBr, cm‾1):
3450 (OH), 2218 (C^N), 1643 (C]O, amide). Anal. Calcd for
C24H24N2O4S (436.92): C, 66.03; H, 5.54; N, 6.42. Found: C, 66.02; H,
5.53; N, 6.44. This powder (4.3 g) was deprotected according to the
general procedure described for deacetylation to give 7b as a yellow
powder (2.78 g, 85% yield), mp 200e201 ꢁC. IR (KBr, cm‾1): 3428
(OH), 2221 (C^N), 1662 (C]O, amide). 1H NMR (300 MHz, DMSO-
C
23H24N2O2S (392.51): C, 70.38; H, 6.16; N, 7.14. Found: C, 70.37; H,
6.17; N, 7.13.
4.2.4.10. 1-(4-Hydroxybutyl)-2-oxo-4,6-di(2-thienyl)nicotinonitrile
(6c). Compound 1c (2.8 g) was reacted with 4-bromobutyl acetate
(1.95 g) according to the general procedure described for alkylation
to give a yellow powder (2.1 g, 53% yield), mp 210e212 ꢁC. IR (KBr,
cm‾1): 2212 (C^N), 1731 (C]O, acetoxy), 1644 (C]O, amide). 1H
d6):
d
1.23 (d, 6H, J ¼ 6.9 Hz, CH3 (i-Pr)), 2.99 (m, 1H, CH (i-Pr)), 3.57
(t, 2H, J ¼ 5.3 Hz, CH2), 3.80 (t, 2H, J ¼ 5.0 Hz, CH2), 4.52 (t, 1H,
J ¼ 5.3 Hz, OH), 5.40 (s, 2H, NCH2O), 7.23 (t, 1H, J ¼ 3.9 Hz, Th), 7.45
(d, 2H, J ¼ 8.1 Hz, AreH), 7.63 (d, 2H, J ¼ 8.1 Hz, AreH), 7.65 (s,1H, 2-
ONN ring), 7.80 (d, 1H, J ¼ 5.1 Hz, Th), 7.85 (d, 1H, J ¼ 4.8 Hz, Th).
Anal. Calcd for C22H22N2O3S (394.49): C, 66.98; H, 5.62; N, 7.10.
Found: C, 66.99; H, 5.62; N, 7.11.
NMR (300 MHz, DMSO-d6):
d 1.76 (m, 2H, CH2), 1.84 (m, 2H, CH2),
1.99 (s, 3H, CH3CO), 4.06 (t, 2H, J ¼ 5.7 Hz, CH2), 4.53 (t, 2H,
J ¼ 6.3 Hz, CH2), 7.23 (t,1H, J ¼ 3.9 Hz, Th), 7.31 (d,1H, J ¼ 5.2 Hz, Th),
7.82 (d, 1H, J ¼ 5.2 Hz, Th), 7.85 (s, 1H, 2-ONN ring), 7.97 (m, 2H, Th),
8.14 (d, 1H, J ¼ 4.8 Hz, Th). Anal. Calcd for C20H18N2O3S2 (398.50): C,
60.28; H, 4.55; N, 7.03. Found: C, 60.27; H, 4.56; N, 7.02. This
powder (4 g) was reacted according to the general procedure
described for deacetylation to give 6c as a yellow powder (2 g, 86%
yield), mp 260e262 ꢁC. IR (KBr, cm‾1): 3450 (OH), 2212 (C^N),
4.2.5. Compounds prepared by alkylation without deacetylation
4.2.5.1. 1-[(2-Acetoxyethoxy)methyl]-2-oxo-4,6-di(2-thienyl)nic-
otinonitrile (7cAc). This compound was prepared from 1c (2.8 g)
and 2-bromomethoxyethyl acetate (1.97 g) according to the general
procedure described above for alkylation and was obtained as a
yellow powder (1.8 g, 45% yield), mp 160e161 ꢁC. IR (KBr, cm‾1):
2214 (C^N), 1732 (C]O, acetoxy), 1643 (C]O, amide). 1H NMR
1638 (C]O, amide). 1H NMR (300 MHz, DMSO-d6):
d 1.68 (m, 2H,
CH2), 1.85 (m, 2H, CH2), 3.45 (t, 1H, J ¼ 4.48 Hz, OH), 3.55 (t, 2H,
J ¼ 5.7 Hz, CH2), 4.50 (t, 2H, J ¼ 6.3 Hz, CH2), 7.16 (t, 1H, J ¼ 3.9 Hz,
Th), 7.26 (d, 1H, J ¼ 5.2 Hz, Th), 7.68 (d, 1H, J ¼ 5.2 Hz, Th), 7.85 (m,
2H, Th), 7.90 (s, 1H, 2-ONN ring), 7.96 (d, 1H, J ¼ 4.8 Hz, Th). Anal.
Calcd for C18H16N2O2S2 (356.46): C, 60.65; H, 4.52; N, 7.86. Found: C,
60.65; H, 4.53; N, 7.85.
(300 MHz, DMSO-d6):
d
2.06 (s, 3H, CH3CO), 3.38 (t, 2H, J ¼ 5.4 Hz,
CH2), 4.44 (t, 2H, J ¼ 5.4 Hz, CH2), 4.72 (s, 2H, NCH2O (a)), 7.23 (t, 1H,
J ¼ 3.9 Hz, Th), 7.33 (d, 1H, J ¼ 5.2 Hz, Th), 7.79 (m, 2H, Th), 7.82 (s,
1H, 2-ONN ring), 7.83 (d, 1H, J ¼ 5.2 Hz, Th), 8.15 (d, 1H, J ¼ 4.8 Hz,
Th). Anal. Calcd for C19H16N2O4S2 (400.47): C, 56.98; H, 4.03; N,
7.00. Found: C, 56.99; H, 4.04; N, 7.02.
4.2.4.11. 4-(4-Chlorophenyl)-1-[(2-hydroxyethoxy)methyl]-2-oxo-6-
(2-pyridyl)nicotinonitrile (7a). Compound 1a (3.07 g) was reacted
with 2-bromomethoxyethyl acetate (1.97 g) according to the gen-
eral procedure described for alkylation to give a yellow powder
(3.2 g, 76% yield), mp 220e222 ꢁC. IR (KBr, cm‾1): 2221 (C^N), 1734
(C]O, acetoxy), 1661 (C]O, amide). 1H NMR (300 MHz, DMSO-d6):
4.2.5.2. 4-(4-Chlorolphenyl)-1-(3-hydroxypropyl)-2-oxo-6-(2-
pyridyl)nicotinonitrile (8a). This compound was prepared from 1a
(3.07 g) and 3-hydroxypropyl chloride (0.94 g) according to the
general procedure described above, and was obtained as a yellow
powder (2.7 g, 74% yield), mp 174e176 ꢁC. IR (KBr, cm‾1): 3328
(OH), 2221 (C^N), 1652 (C]O, amide). 1H NMR (300 MHz, DMSO-
d
2.02 (s, 3H, CH3CO), 3.38 (t, 2H, J ¼ 5.4 Hz, CH2), 4.43 (t, 2H,
d6):
d
1.95 (m, 2H, CH2), 3.31 (t, 2H, J ¼ 5.3 Hz Hz, CH2), 3.62 (t, 2H,
J ¼ 5.4 Hz, CH2), 4.72 (s, 2H, NCH2O), 7.52 (t, 1H, J ¼ 5.1 Hz, Py), 7.63
(d, 2H, J ¼ 8.7 Hz, AreH), 7.74 (d, 2H, J ¼ 8.7 Hz, AreH), 8.02 (t, 1H,
J ¼ 7.5 Hz, Py), 8.12 (s, 1H, 2-ONN ring), 8.48 (d, 1H, J ¼ 8.1 Hz, Py),
8.72 (d, 1H, J ¼ 4.8 Hz, Py). Anal. Calcd for C22H18ClN3O4 (423.85): C,
62.34; H, 4.28; N, 9.91. Found: C, 62.33; H, 4.29; N, 9.92. This
powder (4.2 g) was deprotected according to the general procedure
described for deacetylation to give 7a a yellow powder (1.2 g, 86%
yield), mp 260e262 ꢁC. IR (KBr, cm‾1): 3426 (OH), 2219 (C^N),
J ¼ 5.0 Hz, CH2), 4.69 (t, 1H, J ¼ 5.3 Hz, OH), 7.33 (t, 1H, J ¼ 5.1 Hz,
Py), 7.53 (d, 2H, J ¼ 8.7 Hz, AreH), 7.69 (d, 2H, J ¼ 8.7 Hz, AreH), 8.01
(t, 1H, J ¼ 7.5 Hz, Py), 8.12 (s, 1H, 2-ONN ring), 8.44 (d, 1H, J ¼ 8.1 Hz,
Py), 8.75 (d, 1H, J ¼ 4.8 Hz, Py). Anal. Calcd for C20H16ClN3O2
(365.81): C, 65.67; H, 4.41; N, 11.49. Found: C, 65.68; H, 4.40; N,
11.48.
4.2.5.3. 1-(3-Hydroxypropyl)-4-(4-isopropylphenyl)-2-oxo-6-(2-
thienyl)nicotinonitrile (8b). This compound was prepared from 1b
(3.2 g) and 3-hydroxypropyl chloride (0.94 g) according to the
general procedure described for alkylation and was obtained as a
yellow powder (3.3 g, 88% yield), mp 180e182 ꢁC. IR (KBr, cm‾1):
3384 (OH), 2219 (C^N), 1660 (C]O, amide). Anal. Calcd for
1659 (C]O, amide). 1H NMR (300 MHz, DMSO-d6):
d 3.40 (t, 2H,
J ¼ 5.3 Hz, CH2), 3.83 (t, 2H, J ¼ 5.0 Hz, CH2), 4.63 (t, 1H, J ¼ 5.3 Hz,
OH), 5.98 (s, 2H, NCH2O), 7.55 (t, 1H, J ¼ 5.1 Hz, Py), 7.61 (d, 2H,
J ¼ 8.7 Hz, AreH), 7.69 (d, 2H, J ¼ 8.7 Hz, AreH), 7.98 (t, 1H,
J ¼ 7.5 Hz, Py), 8.05 (s, 1H, 2-ONN ring), 8.40 (d, 1H, J ¼ 8.1 Hz, Py),

396
R.A.I. Abou-Elkhair et al. / European Journal of Medicinal Chemistry 74 (2014) 388e397
C22H22N2O2S (378.49): C, 69.81; H, 5.86; N, 7.40. Found: C, 69.82; H,
5.85; N, 7.42.
(NIH), USA. The compounds were evaluated for their antiviral ac-
tivity against HCV and HBV using RNA Hybridization (Replicon) and
DNA Hybridization (virion) control assays. Cytopathic effect and
neutral red control assays were used with the other viruses.
4.2.5.4. 3-Cyano-1-(3-hydroxypropyl)-4,6-di(2-thienyl)-2-pyridone
(8c). This compound was prepared from 1c (2.8 g) and 3-
hydroxypropyl chloride (0.94 g) according to the general proce-
dure described for alkylation and was obtained as a yellow powder
(2.8 g, 82% yield), mp 180e181 ꢁC. IR (KBr, cm‾1): 3460 (OH), 2217
Acknowledgements
The authors of this article thank Mr. Ahmed Saleh of the
Microbiology Department at Zagazig University for antimicrobial
testing and the Division of Microbiology and Infection Diseases
(DMID)/National Institute of Allergy and Infection Diseases (NIAID)
and the National Institute of Health (NIH), USA for conducting the
antiviral activity studies. This work was sponsored by Zagazig
University, Egypt.
(C^N), 1643 (C]O, amide). 1H NMR (300 MHz, DMSO-d6):
d 1.93
(m, 2H, CH2), 3.33 (t, 2H, J ¼ 5.3 Hz, CH2), 3.63 (t, 2H, J ¼ 5.0 Hz,
CH2), 4.56 (t, 1H, J ¼ 5.3 Hz, OH), 7.23 (t, 1H, J ¼ 3.9 Hz, Th), 7.32 (d,
1H, J ¼ 5.2 Hz, Th), 7.63 (d, 1H, J ¼ 5.2 Hz, Th), 7.83 (s, 1H, 2-ONN
ring), 7.97 (m, 2H, Th), 8.14 (d, 1H, J ¼ 4.8 Hz, Th). Anal. Calcd for
C
17H14N2O2S2 (342.44): C, 59.63; H, 4.12; N, 8.18. Found: C, 59.62; H,
4.13; N, 8.17.
Appendix A. Supplementary data
4.2.5.5. 2-(Allyloxy)-4-(4-chlorolphenyl)-6-(2-pyridyl)nicotinonitrile
(9). This compound was prepared from 1a (2.36 g) and allyl bro-
mide (0.93 g) according to the general procedure described for
alkylation and was obtained as a yellow powder (2.19 g, 82% yield),
mp 176e177 ꢁC. IR (KBr, cm‾1): 2222 (C^N). 1H NMR (300 MHz,
Supplementary data related to this article can be found at http://
dx.doi.org/10.1016/j.ejmech.2013.12.055.
References
DMSO-d6):
d
5.15 (d, 2H, J ¼ 5.4 Hz, CH2), 5.32 (d, 1H, J ¼ 10.2 Hz),
5.56 (d, 1H, J ¼ 17.1 Hz), 6.17 (m, 1H), 7.33 (t, 1H, J ¼ 5.1 Hz, Py), 7.53
(d, 2H, J ¼ 8.7 Hz, AreH), 7.75 (d, 2H, J ¼ 8.7 Hz, AreH), 8.01 (t, 1H,
J ¼ 7.5 Hz, Py), 8.13 (s, 1H, 2-ONN ring), 8.43 (d, 1H, J ¼ 8.1 Hz, Py),
8.74 (d, 1H, J ¼ 4.8 Hz, Py). Anal. Calcd for C20H14ClN3O (347.80): C,
69.07; H, 4.06; N, 12.08. Found: C, 69.08; H, 4.06; N, 12.09.
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4.2.5.6. 4-(4-Chlorophenyl)-2-(prop-2-ynyloxy)-6-(2-pyridyl)nic-
otinonitrile (10). This compound was prepared from 1a (3.05 g) and
propargyl bromide (1.18 g) according to the general procedure
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(2.5 g, 73% yield), mp 180e182 ꢁC. IR (KBr, cm‾1): 2224 (C^N). 1H
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NMR (300 MHz, DMSO-d6):
d 3.68 (s, 1H, hCH), 5.30 (d, 2H,
J ¼ 7.2 Hz, CH2), 7.32 (t,1H, J ¼ 5.1 Hz, Py), 7.54 (d, 2H, J ¼ 8.7 Hz, Are
H), 7.76 (d, 2H, J ¼ 8.7 Hz, AreH), 8.02 (t, 1H, J ¼ 7.5 Hz, Py), 8.13 (s,
1H, 2-ONN ring), 8.44 (d, 1H, J ¼ 8.1 Hz, Py), 8.74 (d, 1H, J ¼ 4.8 Hz,
Py). Anal. Calcd for C20H12ClN3O (345.78): C, 69.47; H, 3.50; N,12.15.
Found: C, 69.46; H, 3.52; N, 12.16.
Hepatitis
C
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