Direct route to novel 2-(β-D-xylo- and arabinopyranosylthio) dihydropyridine glycosides and their corresponding dehydrogenated forms

Article abstract of DOI:10.1080/00397910802379199

A novel method for preparation of a new class of dihydropyridine thioglycosides and their corresponding dehydrogenated forms via reaction of piperidinium salts of dihydropyridinethiones with 2,3,4-tri-O-acetyl-α-D- xylo- and β-D-arabinopyranosyl bromides

Full text of DOI:10.1080/00397910802379199

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Direct Route to Novel
2-(β-D-Xylo- and
Arabinopyranosylthio)
Dihydropyridine Glycosides
and Their Corresponding
Dehydrogenated Forms
G. H. Elgemeie a , E. H. Eltamny b , I. I. Elgawad c &
N. M. Mahmoud c
a Department of Chemistry, Faculty of Science,
Helwan University, Ain-Helwan, Cairo, Egypt
b Chemistry Department, Faculty of Science, Suez
Canal University, Ismaelia, Egypt
c Chemistry Department, Faculty of Science, Suez
Canal University, Suez, Egypt
Version of record first published: 08 Jan 2009.
To cite this article: G. H. Elgemeie , E. H. Eltamny , I. I. Elgawad & N. M.
Mahmoud (2009): Direct Route to Novel 2-(β-D-Xylo- and Arabinopyranosylthio)
Dihydropyridine Glycosides and Their Corresponding Dehydrogenated Forms, Synthetic
Communications: An International Journal for Rapid Communication of Synthetic
Organic Chemistry, 39:3, 443-458
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Synthetic Communications1, 39: 443–458, 2009
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print/1532-2432 online
DOI: 10.1080/00397910802379199
Direct Route to Novel 2-(b-D-Xylo- and
Arabinopyranosylthio)Dihydropyridine
Glycosides and Their Corresponding
Dehydrogenated Forms
G. H. Elgemeie,1 E. H. Eltamny,2 I. I. Elgawad,3
and N. M. Mahmoud3
1Department of Chemistry, Faculty of Science, Helwan University,
Ain-Helwan, Cairo, Egypt
2Chemistry Department, Faculty of Science, Suez Canal University,
Ismaelia, Egypt
3Chemistry Department, Faculty of Science, Suez Canal University, Suez, Egypt
Abstract: A novel method for preparation of a new class of dihydropyridine
thioglycosides and their corresponding dehydrogenated forms via reaction of
piperidinium salts of dihydropyridinethiones with 2,3,4-tri-O-acetyl-a-D-xylo-
and b-D-arabinopyranosyl bromides has been studied.
In recent years, several pyrimidine analogs with altered carbon skeletons
and unusual substitution patterns have been found to possess activity
against a number of viral infections. Chemical modification of these
nucleosides is an important approach to the chemotherapy of virus infec-
tions as well as of cancer. In recent reports from our laboratory, we
described the preparation of different novel functionalized pyridinethione
glycosides, which revealed antagonistic activity against human carcinoma
cells and HIV virus.[1–4] In an earlier brief communication, we had reported
the use of dihydropyridinethione glycosides as P-glycoprotein (Pgp) sub-
strates or inhibitors in the protein glycosylation process.[5] These common
features encouraged us to develop a new straightforward route for the syn-
thesis of these compounds. In the present report, we describe the synthesis
Received April 27, 2008.
Address correspondence to Prof. Dr. Galal H. Elgemeie, Chemistry Depart-
ment, Faculty of Science, Helwan University, Helwan, Egypt. E-mail: elgemeie@
yahoo.com
443

444
G. H. Elgemeie et al.
of dihydropyridine thioglycosides through reaction of piperidinium salts of
dihydropyridinethiolates with acetylated glycosyl halides. As far as we
know, this is the first coupling reaction of this type to be reported for glyco-
side formation. Thus, it has been found that arylmethylidenecyanothioace-
tamide 1 reacted with 3-oxo-N-arylbutanamides 2 in ethanol containing
piperidine at 0 ꢀC to give the corresponding piperidinium salts of 1,4-dihy-
dropyridine-2-thiones 3 (Chart 1). The structures of 3 was established on
the basis of their elemental analyses and spectral data. Compounds 3 react
with 2,3,4-tri-O-acetyl-a-D-xylo- and b-D-arabinopyranosyl bromides
4a,b in acetone at 0 ꢀC to give in a high yield the corresponding S-xylosides
5a–f and S-arabinosides 5g–l, respectively. The structures of the reaction
products 5a–l were established by their elemental analyses and spectral data
1
(IR, H NMR, 13C NMR). As an example, the analytical data for 5l
1
revealed a molecular formula C31H29Cl2N3SO8. The H NMR spectrum
showed the anomeric proton as a doublet at d 6.10 ppm. The other five
arabinose protons resonated at d 3.30–5.20 ppm, and the three acetyl
groups appeared as three singlets at d 2.05–2.10 ppm. The 13C NMR spec-
trum of 5l contained a signal at d 80.50 ppm corresponding to the C-10 atom
and four signals appearing at d 65.50–69.80 ppm that were assigned to (C-
40, C-20, C-30, C-50) respectively. The formation of S -glycosides 5 and not
the corresponding N-glycosides 7 (Chart 1) were proved using 13C NMR
spectroscopy, which revealed the absence of the thione carbon at d 178 ppm
ppm and the appearance of a signal at d 158.90 ppm corresponding to the
CꢁS carbon, whose chemical shift is the same as that of the corresponding
S-methyl derivative.[6,7] In another experiment, the piperidinium salts 3
reacted with 2,3,4-tri-O-acetyl-a-D-xylo- and b-D-arabinopyranosyl bro-
mides in acetone at 30 ꢀC to afford the corresponding aromatized pyridine
thioxylosides 8a–f and thioarabinosides 8g–l (Chart 2). Compounds 8
could also be prepared by heating the dihydrothioglycosides 5 in ethanol
for 3 min, which underwent spontaneous auto-oxidation to afford the aro-
matized thioglycosides 8. The structures of the reaction products 8a–l were
established and confirmed on the basis of their elemental analyses and spec-
tral data (IR, 1H NMR, 13C NMR). When glycosides 8 were treated with
methanolic ammonia at room temperature, the free glycoside derivatives
9a–l were obtained, the structures of which were established on the basis
of elemental analyses and spectral data. Thus, the analytical data for 9d
revealed molecular formula C25H22ClN3SO5. The 1H NMR spectrum
showed the anomeric proton as a doublet at d 5.79 ppm, indicating a b-
D-configuration. The signals of the other five xylose protons appeared as
a multiplet at d 3.00–4.15 ppm, and the signals at d 5.15–5.60 ppm were
assigned to the three hydroxyl groups.
In summary, we have achieved a novel synthesis of interesting
nonclassical dihydropyridine thioglycosides and their corresponding

Direct Route to Novel 2-(b-D-Xylo- and Arabinopyranosylthio)
445
Chart 1. Reaction of piperidinium salts of dihydropyridinethiones 3 with 2,3,4-
tri-O-acetyl-a-D-xylo- and b-D-arabinopyranosyl bromides 4.

446
G. H. Elgemeie et al.
Chart 2. Reaction of pyridinethiones 10 with 2,3,4-tri-O-acetyl-a-D-xylo- and
b-D-arabinopyranosyl bromides 4.
aromatized forms by the reaction of the piperidinium salts of dihydro-
pyridinethiones with acetylated glycosyl halides; the nature of the pro-
ducts depends on the applied thermodynamic factors. These glycosides
can be utilized as excellent starting materials for the synthesis of other
carbohydrate derivatives and for further biological evaluation studies.
EXPERIMENTAL
All evaporations were carried out under reduced pressure at 40 ꢀC, and
melting points are uncorrected. Aluminum sheets coated with silica gel

Direct Route to Novel 2-(b-D-Xylo- and Arabinopyranosylthio)
Table 1. Derivatives of compounds 5,8
447
5,8
Ar1
Ar2
R1
R2
a
b
c
d
e
f
g
h
i
4-H3COꢁC6H4
4-H3COꢁC6H4
4-H3COꢁC6H4
4-ClꢁC6H4
C6H5
H
H
H
H
H
OAc
OAc
OAc
OAc
OAc
OAc
H
H
H
H
H
4-H3CꢁC6H4
4-ClꢁC6H4
C6H5
4-H3CꢁC6H4
4-ClꢁC6H4
C6H5
4-H3CꢁC6H4
4-ClꢁC6H4
C6H5
4-ClꢁC6H4
4-ClꢁC6H4
H
4-H3COꢁC6H4
4-H3COꢁC6H4
4-H3COꢁC6H4
4-ClꢁC6H4
OAc
OAc
OAc
OAc
OAc
OAc
j
k
l
4-ClꢁC6H4
4-H3CꢁC6H4
4-ClꢁC6H4
4-ClꢁC6H4
H
F254 (Merck) were used for thin-layer chromatography (TLC). Detection
was effected by viewing under a short-wavelength UV lamp. IR spectra
were obtained (KBr disk) on a Pye Unicam spectra 1000. 1H NMR
and 13C NMR spectra were measured on a Wilmad 270-MHz or on a
Varian 400-MHz spectrometer for solution in CDCl3 or (CD3)2SO with
SiMe4 as internal standard. Analytical data were obtained from the
Microanalytical Data Center at Cairo University.
Compounds 3 and 10 were prepared following reported procedures.[8]
Table 2. Derivatives of compounds 6,9
6,9
Ar1
Ar2
C6H5
4-H3CꢁC6H4
4-ClꢁC6H4
C6H5
4-H3CꢁC6H4
4-ClꢁC6H4
C6H5
4-H3CꢁC6H4
4-ClꢁC6H4
C6H5
R1
R2
a
b
c
d
e
f
g
h
i
4-H3COꢁC6H4
4-H3COꢁC6H4
4-H3COꢁC6H4
4-ClꢁC6H4
H
H
H
H
H
OH
OH
OH
OH
OH
OH
H
H
H
H
H
4-ClꢁC6H4
4-ClꢁC6H4
H
4-H3COꢁC6H4
4-H3COꢁC6H4
4-H3COꢁC6H4
4-ClꢁC6H4
OH
OH
OH
OH
OH
OH
j
k
l
4-ClꢁC6H4
4-H3CꢁC6H4
4-ClꢁC6H4
4-ClꢁC6H4
H

448
G. H. Elgemeie et al.
Piperidinium 6-Methyl-3-cyano-1,4-dihydropyridine-2-thiolates (3a–f)
A mixture of arylmethylidenecyanothioacetamides 1a,b (0.01 mol) and
3-oxo-N-arylbutanamides 2a–c (0.01 mol) were dissolved in dry ethanol
(10 ml), and then piperidine (0.01 mol) was added. The reaction mixture
was stirred at 0 ꢀC for 1 h and then left to cool at room temperature.
The solvent was removed at reduced pressure, and the resulting piperidi-
nium salt of 1,4-dihydropyridine-2-thione 3 was collected by filtration
and washed with ether.
Compound 3a: Yellow, mp 207 ꢀC, yield (57%). IR nmax=cmꢁ1 (KBr)
3400 (NH); 2210 (CN); 1650 (CO).
Compound 3b: Yellow, mp 228 ꢀC, yield (60%). IR nmax=cmꢁ1 (KBr)
3350 (NH); 2220 (CN); 1680 (CO).
Compound 3c: Yellow, mp 222 ꢀC, yield (55%). IR nmax=cmꢁ1 (KBr)
3370 (NH); 2220 (CN); 1640 (CO).
Compound 3d: Yellow, mp 214 ꢀC, yield (35%). IR nmax=cmꢁ1 (KBr)
3300 (NH); 2215 (CN); 1670 (CO).
Compound 3e: Yellow, mp 150 ꢀC, yield (50%). IR nmax=cmꢁ1 (KBr)
3310 (NH); 2210 (CN); 1650 (CO).
Compound 3f: Yellow, mp 210 ꢀC, Yield (55%). IR. nmax=cmꢁ1 (KBr)
3310 (NH); 2201 (CN); 1660 (CO).
4-Aryl-3-cyano-6-metyl-2-(20,30,40-tri-O-acetyl-b-D-xylo- and
Arabinopyranosylthio)-1,4-dihydropyridines (5a–l)
The piperidinium salt of 1,4-dihydropyridine-2-thione 3 was dissolved in
dry acetone (5 ml), and a solution of 2,3,4-tri-O-acetyl-a-D-xylo- or
b-D-arabinopyranosyl bromide 4a,b (0.01 mol) in dry acetone (20 ml)
was then added at 0 ꢀC. The reaction mixture was stirred until the reac-
tion was judged complete by TLC, using chloroform–ether (4:1), then
concentrated under reduced pressure. The residue crystallized from
chloroform–petroleum ether at 0 ꢀC.
Compound 5a: Yellow, mp 125 ꢀC, yield (50%). IR nmax=cmꢁ1 (KBr)
3310 (NH); 2201 (CN); 1754 (CO); 1658 (CO amide).1H NMR: d 2.00–
2.18 (t, 9H, 3H3CO); 2.31 (s, 3H, CH3); 3.99 (s, 3H, OCH3); 3.59–5.18
(m, 5H, 2H-50, H-40, H-30, H-20); 4.53 (s, 1H, pyridine H-4); 6.12 (d,
1H, H-10); 6.78–7.75 (m, 9H, C6H5, C6H4); 8.34 (s, 1H, NH); 9.28 (s,
1H, NH). C32H33N3O9S calcd.: C, 60.45%; H, 5.23%; N, 6.61%. Found:
C, 60.50%; H, 5.23%; N, 6.62%.
Compound 5b: Yellow, mp 113 ꢀC, yield (41%). IR nmax=cmꢁ1 (KBr)
1
3321 (NH); 2202 (CN); 1755 (CO); 1660 (CO amide). H NMR: d 2.05–
2.16 (t, 9H, 3H3CO); 2.37 (s, 3H, CH3); 2.55 (s, 3H, CH3); 3.80 (s, 3H,

Direct Route to Novel 2-(b-D-Xylo- and Arabinopyranosylthio)
449
OCH3); 3.70–5.57 (m, 5H, 2H-50, H-40, H-30, H-20); 4.66 (s, 1H, pyridine
H-4); 6.21 (d, 1H, H-10); 6.80–7.59 (m, 8H, 2C6H4); 8.77 (s, 1H, NH);
9.50 (s, 1H, NH). C33H35N3O9S calcd.: C, 61.00%; H, 5.43%; N,
6.46%. Found: C, 61.15%; H, 5.50%; N, 6.48%.
Compound 5c: Yellow, mp 110 ꢀC, yield (41%). IR nmax=cmꢁ1 (KBr)
1
3303 (NH); 2202 (CN); 1756 (CO); 1662 (CO amide). H NMR: d 2.07–
2.13 (t, 9H, 3H3CO); 2.33 (s, 3H, CH3); 3.83 (s, 3H, OCH3); 3.71–5.27 (m,
5H, 2H-50, H-40, H-30, H-20); 4.44 (s, 1H, pyridine H-4); 6.34 (d, 1H, H-
10); 6.97–7.41 (m, 8H, 2C6H4); 8.88 (s, 1H, NH); 9.20 (s, 1H, NH).
C32H32ClN3O9S calcd.: C, 57.35%; H, 4.81%; N, 6.27%. Found: C,
57.52%; H, 4.80%; N, 6.29%.
Compound 5d: Yellow, mp 211 ꢀC, yield: (47.7%). IR nmax=cmꢁ1
1
(KBr) 3260 (NH); 2224 (CN); 1753 (CO); 1651 (CO amide). H NMR:
d 2.03–2.14 (t, 9H, 3H3CO); 2.72 (s, 3H, CH3); 3.6–5.25 (m, 5H, 2H-50,
H-40, H-30, H-20); 4.56 (s, 1H, pyridine H-4); 6.30 (d, 1H, H-10); 7.06–
7.42 (m, 9H, C6H4, C6H5); 8.34 (s, 1H, NH); 7.90 (1H, NH).
C31H30ClN3O8S calcd.: C, 58.16%; H, 4.72%; N, 6.56%. Found: C,
58.32%; H, 5.00%; N, 6.55%.
Compound 5e: Yellow, mp 124 ꢀC, yield (75%). IR nmax=cmꢁ1 (KBr)
1
3334 (NH); 2204 (CN); 1759 (CO); 1662 (CO amide). H NMR: d 1.99–
2.22 (t, 9H, 3H3CO); 2.30 (s, 3H, CH3); 2.73 (s, 3H, CH3); 3.78–5.66 (m,
5H, 2H-50, H-40, H-30, H-20); 4.85 (s, 1H, pyridine H-4); 6.15 (d, 1H, H-
10); 6.77–7.56 (m, 8H, 2C6H4); 8.70 (s, 1H, NH); 9.90 (s, 1H, NH).
C32H32ClN3O8S calcd.: C, 58.75%; H, 4.93%; N, 6.42%. Found: C,
58.77%; H, 5.00%; N, 6.55%.
Compound 5f: Yellow, mp 97 ꢀC, yield (76.3%). IR nmax=cmꢁ1 (KBr)
1
3333 (NH); 2204 (CN); 1753 (CO); 1680 (CO amide). H NMR: d 2.00–
2.29 (t, 9H, 3H3CO); 2.60 (s, 3H, CH3); 3.56–5.15 (m, 5H, 2H-50, H-40,
H-30, H-20); 4.19 (s, 1H, pyridine H-4); 6.20 (d, 1H, H-10); 7.00–7.76 (m,
8H, 2C6H4); 8.00 (s, 1H, NH); 8.50 (1H, NH). C31H29Cl2N3O8S calcd.:
C, 55.19%; H, 4.33%; N, 6.23%. Found: C, 55.30%; H, 4.50%; N, 6.25%.
Compound 5g: Yellow, mp 125 ꢀC, yield (78%). IR nmax=cmꢁ1 (KBr)
1
3316 (NH); 2201 (CN); 1750 (CO); 1657 (CO amide). H NMR: d 2.06–
2.10 (t, 9H, 3H3CO); 2.26 (s, 3H, CH3); 3.77 (s, 3H, OCH3); 3.60–5.11 (m,
5H, 2H-50, H-40, H-30, H-20); 4.40 (s, 1H, pyridine H-4); 6.10 (d, 1H, H-
10); 6.60–7.50 (m, 9H, C6H5,C6H4); 8.60 (s, 1H, NH); 9.00 (s, 1H, NH).
C32H33N3O9S calcd.: C, 60.45%; H, 5.23%; N, 6.61%. Found: C,
60.47%; H, 5.25%; N, 6.60%.
Compound 5h: Yellow, mp 120 ꢀC, yield (77%). IR nmax=cmꢁ1 (KBr)
1
3341 (NH); 2224 (CN); 1753 (CO); 1660 (CO amide). H NMR: d 2.05–
2.15 (t, 9H, 3H3CO); 2.38 (s, 3H, CH3); 2.62 (s, 3H, CH3); 3.88 (s, 3H,
OCH3); 4.05–5.40 (m, 5H, H-50, H-40, H-30, H-20); 4.45 (s, 1H, pyridine
H-4); 6.4 (d, 1H, H-10); 6.80–7.45 (m, 8H, 2C6H4); 8.30 (s, 1H, NH);

450
G. H. Elgemeie et al.
8.90 (1H, NH). C33H35N3O9S calcd.: C, 61.00%; H, 5.43%; N, 6.46%.
Found: C, 61.02%; H, 5.50%; N, 6.47%.
Compound 5i: Yellow, mp 110 ꢀC, yield (70%). IR nmax=cmꢁ1 (KBr)
3318 (NH); 2223 (CN); 1750 (CO); 1680 (CO amide). 1H NMR: d
2.00–2.18 (t, 9H, 3H3CO); 2.54 (s, 3H, CH3); 3.90 (s, 3H, OCH3);
3.70–5.65 (m, 5H, 2H-50, H-40, H-30, H-20); 4.40 (s, 1H, pyridine H-4);
6.22 (d, 1H, H-10); 6.90–7.40 (m, 8H, 2C6H4); 8.70 (s, 1H, NH); 9.10
(s, 1H, NH). C32H32ClN3O9S calcd.: C, 57.35%; H, 4.81%; N, 6.27%.
Found: C, 57.32%; H, 5.00%; N, 6.29%.
Compound 5j: Yellow, mp 125 ꢀC, yield (74%). IR nmax=cmꢁ1 (KBr)
1
3323.9 (NH); 2202 (CN); 1752 (CO); 1658.5 (CO amide). H NMR: d
2.03–2.08 (t, 9H, 3H3CO); 2.34 (s, 3H, CH3); 3.80–5.45 (m, 5H, H-50,
H-40, H-30, H-20); 4.20 (s, 1H, pyridine H-4); 6.40 (d, 1H, H-10); 6.85–
7.60 (m, 8H, 2C6H4); 8.50 (s, 1H, NH); 8.78 (1H, NH). C31H30ClN3O8S
calcd.: C, 58.16%; H, 4.72%; N, 6.56%. Found: C, 58.18%; H, 5.00%;
N, 6.57%.
Compound 5k: Yellow, mp 113 ꢀC, yield (63%). IR nmax=cmꢁ1 (KBr)
1
3341 (NH); 2203 (CN); 1752 (CO); 1660 (CO of amide). H NMR: d
1.90–2.20 (t, 9H, 3H3CO); 2.44 (s, 3H, CH3); 2.79 (s, 3H, CH3); 3.55–
5.75 (m, 5H, 2H-50, H-40, H-30, H-20); 4.39 (s, 1H, pyridine H-4); 6.10
(d, 1H, H-10); 6.43–7.76 (m, 8H, 2C6H4); 8.90 (s, 1H, NH); 9.65 (s, 1H,
NH). C32H32ClN3O8S calcd.: C, 58.75%; H, 4.93%; N, 6.42%. Found:
C, 58.76%; H, 5.05%; N, 6.44%.
Compound 5l: Yellow, mp 110 ꢀC, yield (93%). IR nmax=cmꢁ1 (KBr)
1
3327 (NH); 2202 (CN); 1750 (CO); 1680 (CO amide). H NMR: d 2.05–
2.10 (t, 9H, 3H3CO); 2.70 (s, 3H, CH3); 3.30–5.20 (m, 5H, 2H-50, H-40,
H-30, H-20); 4.20 (s, 1H, pyridine H-4); 6.10 (d, 1H, H-10); 7.30–7.75
(m, 8H, 2C6H4); 8.20 (s, 1H, NH); 8.80 (1H, NH).13C NMR: 20.30–
20.50 (3 CH3CO); 22.90 (CH3); 65.50–80.50 (C-50 C-40, C-30, C-20,
C-10); 105.20 (C-3); 114.20 (CN); 120.00–134.00 (2C6H4); 136.74 (C-5);
150.20 (C-4); 158.00 (C-6); 158.90 (C-S); 163.80 (CONH) 169.00–169.99
(3CO). C31H29Cl2N3O8S calcd.: C, 55.19%; H, 4.33%; N, 6.229%.
Found: C, 55.28%; H, 4.50%; N, 6.20%.
4-Aryl-3-cyano-6-metyl-2-(b-D-xylo- and Arabinopyranosylthio)-1,4-
dihydropyridines (6a-l)
Dry gaseous ammonia was passed through a solution of protected glyco-
sides 5 (0.5 g) in dry methanol (20 ml) at room temperature for 10 min.
The mixture was stirred overnight (followed by TLC). The resulting
mixture was then evaporated under reduced pressure to afford a solid
residue that was crystallized from ether.

Direct Route to Novel 2-(b-D-Xylo- and Arabinopyranosylthio)
451
Compound 6a: Brown, mp 105 ꢀC, yield (78.5%). IR nmax=cmꢁ1
1
(KBr) 3292–3390 (OH, NH); 2199 (CN); 1659 (CO amide). H NMR:
d 2.30 (s, 3H, CH3); 3.80 (s, 3H, OCH3); 3.30–4.00 (m, 5H, 2H-50, H-
40, H-30, H-20); 4.40 (s, 1H, pyridine H-4); 5.10–5.60 (m, 3H, 20ꢁOH,
30ꢁOH, 40ꢁOH); 6.10 (d, 1H, H-10); 6.70–7.70 (m, 9H, C6H5,C6H4);
8.87 (s, 1H, NH); 9.10 (s, 1H, NH). C26H27 N3O6S calcd.: C, 61.28%;
H, 5.34%; N, 8.24%. Found: C, 61.33%; H, 5.50%; N, 8.51%.
Compound 6b: Yellow, mp 116 ꢀC, yield (56%). IR nmax=cmꢁ1 (KBr)
3316–3450 (OH, NH); 2199 (CN); 1659 (CO amide). 1H NMR: d 2.45 (s,
3H, CH3); 3.90 (s, 3H, OCH3); 3.60–4.00 (m, 5H, 2H-50, H-40, H-30, H-20);
4.40 (s, 1H, pyridine H-4); 5.08–5.57 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH);
6.21 (d, 1H, H-10); 6.80–7.59 (m, 8H, 2C6H4); 8.60 (s, 1H, NH); 9.50
(s, 1H, NH). C27H29N3O6S calcd.: C, 61.93%; H, 5.58%; N, 8.02%.
Found: C, 61.95%; H, 5.59%; N, 8.05%.
Compound 6c: Yellow, mp 108 ꢀC, yield (58%). IR nmax=cmꢁ1 (KBr)
3298–3480 (OH, NH); 2224 (CN); 1659 (CO of amide). 1H NMR: d 2.30
(s, 3H, CH3); 3.98 (s, 3H, OCH3); 3.21–4.11 (m, 5H, 2H-50, H-40, H-30, H-
20); 4.20 (s, 1H, pyridine H-4); 5.00–5.70 (m, 3H, 20ꢁOH, 30ꢁOH,
40ꢁOH); 6.11 (d, 1H, H-10); 6.90–7.50 (m, 8H, 2C6H4); 8.60 (s, 1H,
NH); 9.00 (s, 1H, NH). C26H26ClN3O6S calcd.: C, 57.39%; H, 4.81%;
N, 7.72%. Found: C, 57.33%; H, 5.00%; N, 7.90%.
Compound 6d: Brown, mp 120 ꢀC, yield (75%). IR nmax=cmꢁ1 (KBr)
3289–3460 (OH, NH); 2225 (CN); 1657 (CO amide). 1H NMR: d 2.55 (s,
3H, CH3); 3.40–4.09 (m, 5H, 2H-50, H-40, H-30, H-20); 4.34 (s, 1H, pyri-
dine H-4); 5.00–5.55 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH); 6.10 (d, 1H, H-
10); 7.11–7.78 (m, 9H, C6H4, C6H5); 8.00 (s, 1H, NH); 8.60 (1H, NH).
C25H24ClN3O5S calcd.: C, 58.41%; H, 4.70%; N, 8.17%. Found: C,
58.42%; H, 4.70%; N, 8.18%.
Compound 6e: Brown, mp 109 ꢀC, yield (78%). IR nmax=cmꢁ1 (KBr)
3309–3460 (OH, NH); 2199 (CN); 1659 (CO amide). 1H NMR: d 2.22 (s,
3H, CH3); 2.50 (s, 3H, CH3); 3.66–4.00 (m, 5H, 2H-50, H-40, H-30, H-20);
4.45 (s, 1H, pyridine H-4); 5.00–5.70 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH);
6.15 (d, 1H, H-10); 6.60–7.80 (m, 8H, 2C6H4); 8.64 (s, 1H, NH); 9.40
(s, 1H, NH). C26H26ClN3O5S calcd.: C, 59.13%; H; 4.96%; N, 7.95%.
Found: C, 59.15%; H, 4.96%; N, 8.00%.
Compound 6f: Yellow, mp 111 ꢀC, yield (67%). IR nmax=cmꢁ1 (KBr)
3316–3480 (OH, NH); 2201 (CN); 1660 (CO of amide). 1H NMR: d 2.40
(s, 3H, CH3); 3.33–3.85 (m, 5H, 2H-50, H-40, H-30, H-20); 4.10 (s, 1H, pyri-
dine H-4); 5.00–5.70 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH); 6.10 (d, 1H, H-
10); 7.32–7.88 (m, 8H, 2C6H4); 8.20 (s, 1H, NH); 8.80 (1H, NH).
C25H23Cl2N3O5S calcd.: C, 54.74%; H, 4.22%; N, 7.66%. Found: C,
54.77%; H, 4.22%; N, 7.72%.

452
G. H. Elgemeie et al.
Compound 6g: Yellow, mp 112 ꢀC, yield (60%). IR nmax=cmꢁ1 (KBr)
3307–3430 (OH, NH); 2222 (CN); 1658 (CO amide). 1H NMR: d 2.20 (s,
3H, CH3); 3.70 (s, 3H, OCH3); 3.80–4.22 (m, 5H, 2H-50, H-40, H-30, H-20);
4.40 (s, 1H, pyridine H-4); 5.20–5.50 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH);
6.10 (d, 1H, H-10); 6.70–7.70 (m, 9H, C6H5, C6H4); 8.70 (s, 1H, NH);
9.10 (s, 1H, NH). C26H27N3O6S calcd.: C, 61.28%; H, 5.34%; N,
8.25%. Found: C, 61.30%; H, 5.35%; N, 8.34%.
Compound 6h: Brown, mp 108 ꢀC, yield (70%). IR nmax=cmꢁ1 (KBr)
3309–3450 (OH, NH); 2223 (CN); 1659 (CO amide). 1H NMR: d 2.30 (s,
3H, CH3); 2.52 (s, 3H, CH3); 3.90 (s, 3H, OCH3); 4.05–4.40 (m, 5H, H-50,
H-40, H-30, H-20); 4.45 (s, 1H, pyridine H-4); 5.00–5.70 (m, 3H, 20ꢁOH,
30ꢁOH, 40ꢁOH); 6.4 (d, 1H, H-10); 6.70–7.60 (m, 8H, 2C6H4); 8.55 (s,
1H, NH); 8.99 (1H, NH). C27H29N3O6S calcd.: C, 61.93%; H, 5.58%;
N, 8.02%. Found: C, 61.93%; H, 5.59%; N, 8.06%.
Compound 6i: Brown, mp 112 ꢀC, yield (70%). IR nmax=cmꢁ1 (KBr)
1
3314–3470 (OH, NH); 2221 (CN); 1658 (CO of amide). H NMR: d 2.40
(s, 3H, CH3); 3.80 (s, 3H, OCH3); 3.89–4.20 (m, 5H, 2H-50, H-40, H-30, H-
20); 4.50 (s, 1H, pyridine H-4); 5.10–5.70 (m, 3H, 20ꢁOH, 30ꢁOH,
40ꢁOH); 6.12 (d, 1H, H-10); 6.60–7.80 (m, 8H, 2C6H4); 8.77 (s, 1H,
NH); 9.90 (s, 1H, NH). C26H26ClN3O6S calcd.: C, 57.39%; H, 4.81%;
N, 7.72%. Found: C, 57.30%; H, 5.00%; N, 7.85%.
Compound 6j: Brown, mp 120 ꢀC, yield (70%). IR nmax=cmꢁ1 (KBr)
1
3303–3420 (OH, NH); 2199 (CN); 1659 (CO of amide). H NMR: d 2.30
(s, 3H, CH3); 3.80–4.15 (m, 5H, H-50, H-40, H-30, H-20); 4.20 (s, 1H, pyri-
dine H-4); 5.10–5.70 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH); 6.10 (d, 1H, H-
10); 6.55–7.70 (m, 8H, 2C6H4); 8.32 (s, 1H, NH); 8.80 (1H, NH).
C25H24ClN3O5S calcd.: C, 58.41%; H, 4.70%; N, 8.17%. Found: C,
58.45%; H, 4.90%; N, 8.18%.
Compound 6k: Brown, mp 109 ꢀC, yield (75%). IR nmax=cmꢁ1 (KBr)
3311–3450 (OH, NH); 2222 (CN); 1658 (CO amide).1H NMR: d 2.33 (s,
3H, CH3); 2.80 (s, 3H, CH3); 3.55–4.09 (m, 5H, 2H-50, H-40, H-30, H-20);
4.30 (s, 1H, pyridine H-4); 5.00–5.60 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH);
6.10 (d, 1H, H-10); 6.50–7.80 (m, 8H, 2C6H4); 8.96 (s, 1H, NH); 9.70
(s, 1H, NH). C26H26ClN3O5S calcd.: C, 59.13%; H, 4.96%; N, 7.95%.
Found: C, 59.15%; H, 4.95%; N, 7.99%.
Compound 6l: Brown, mp 122 ꢀC, yield (75%). IR nmax=cmꢁ1 (KBr)
3312–3470 (OH, NH); 2200 (CN); 1658 (CO amide). 1H NMR: d 2.60 (s,
3H, CH3); 3.30–4.00 (m, 5H, 2H-50, H-40, H-30, H-20); 4.10 (s, 1H,
pyridine H-4); 5.10–5.60 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH); 6.12 (d,
1H, H-10); 7.33–7.79 (m, 8H, 2C6H4); 8.19 (s, 1H, NH); 8.88 (1H, NH).
C25H23Cl2N3O5S calcd.: C, 54.74%; H, 4.22%; N, 7.66%. Found: C,
54.73%; H, 4.24%; N, 7.70%.

Direct Route to Novel 2-(b-D-Xylo- and Arabinopyranosylthio)
453
4-Aryl-3-cyano-6-metyl-2-(20,30,40-tri-O-acetyl-b-D-xyloso- and
Arabinopyranosylthio) pyridines (8a–l)
Method A
The piperidinium salts of dihydropyridinethione 3 (0.01 mol) were dis-
solved in dry acetone (5 ml), and a solution of 2,3,4-tri-O-acetyl-a-D-xylo-
or b-D-arabinopyranosyl bromide 4a,b (0.01 mol) in dry acetone (20 ml)
was then added at 30 ꢀC. The reaction mixture was stirred until the reac-
tion was judged complete by TLC, using chloroform–petroleum ether 9:1,
then concentrated under reduced pressure at 40 ꢀC. The resulting product
was crystallized from ethanol.
Method B
A suspension of dihydropyridine thioglycosides 5 (0.01 mol) in ethanol
were refluxed with stirring for 3 min. The resulting products were
collected by filtration and crystallized from ethanol.
Method C
To a solution of condensed pyridine-2(1H)-thiones 10a–f (0.01 mol) in
aqueous potassium hydroxide [0.569 g, 0.01 mol, in distilled water (6 ml)]
was added a solution of 2,3,4-tri-O-acetyl-a-D-xylo- or b-D-arabinopyr-
anosyl bromide 4a,b (4.521 g, 0.011 mol) in acetone (30 ml). The reaction
mixture was stirred at room temperature until reaction judged to be com-
plete by TLC (2 h). The mixture was evaporated under reduced pressure
at 40 ꢀC, and the residue was washed with distilled water to remove the
formed potassium bromide. The product was dried and crystallized from
ethanol.
Data
Compound 8a: Yellow, mp 144 ꢀC, yield (60%). IR nmax=cmꢁ1 (KBr)
3425 (NH); 2228 (CN); 1758 (CO); 1679 (CO amide). 1H NMR: d
1.99–2.09 (t, 9H, 3COCH3); 2.40 (s, 3H, CH3); 3.90 (s, 3H, OCH3);
4.10–5.50 (m, 5H, 2H-50, H-40, H-30, H-20); 6.20 (d, 1H, H-10); 6.80–
7.90 (m, 9H, C6H5, C6H4); 10.29 (s, 1H, NH). C32H31N3O9S calcd.: C,
60.65%; H, 4.93%; N, 6.63%. Found: C, 60.68%; H, 5.00%; N, 6.65%.
Compound 8b: Yellow, mp 145 ꢀC, yield (44%). IR nmax=cmꢁ1
(KBr) 3317 (NH); 2225 (CN); 1754 (CO); 1656 (CO of amide).

454
G. H. Elgemeie et al.
1H NMR: d 2.03–2.06 (t, 9H, 3COCH3); 2.43 (s, 3H, CH3); 2.62 (s, 3H,
CH3); 3.75 (s, 3H, OCH3); 4.15–5.40 (m, 5H, 2H-50, H-40, H-30, H-20);
6.22 (d, 1H, H-10); 6.99–7.42 (m, 8H, 2C6H4); 10.29 (s, 1H, NH).
C33H33N3O9S calcd.: C, 61.19%; H, 5.13%; N, 6.48%. Found: C,
61.20%; H, 5.13%; N, 6.50%.
Compound 8c: Yellow, mp 165 ꢀC, yield (33%). IR nmax=cmꢁ1
1
(KBr) 3314 (NH); 2224 (CN); 1757 (CO); 1680 (CO amide). H NMR:
d 2.10–2.13 (t, 9H, 3H3CO); 2.70 (s, 3H, CH3); 3.79 (s, 3H, OCH3);
3.63–5.27 (m, H-50, H-40, H-30, H-20); 6.32 (d, 1H, H-10); 6.93–7.40 (m,
9H, 2C6H4, NH). C32H30ClN3O9S calcd.: C, 57.52%; H, 4.52%; N,
6.28%. Found: C, 57.58%; H, 4.70%; N, 6.29%.
Compound 8d: Yellow, mp 242 ꢀC, yield (58%). IR nmax=cmꢁ1 (KBr)
1
3259 (NH); 2223 (CN); 1753 (CO); 1648 (CO amide). H NMR: d 2.08–
2.19 (t, 9H, 3H3CO); 2.60 (s, 3H, CH3); 3.50–5.30 (m, H-50, H-40, H-30, H-
20); 6.10 (d, 1H, H-10); 6.90–7.70 (m, 9H, C6H5, C6H4); 10.29 (s, 1H, NH).
C31H28ClN3O8S calcd.: C, 58.34%; H, 4.42%; N, 6.58%. Found: C,
58.38%; H, 4.42%; N, 6.60%.
Compound 8e: Yellow, mp 150 ꢀC, yield (60%). IR nmax=cmꢁ1 (KBr)
1
3312 (NH); 2226 (CN); 1754 (CO); 1681 (CO amide). H NMR: d 2.03–
2.06 (t, 9H, 3H3CO); 2.22 (s, 3H, CH3); 2.64 (s, 3H, CH3); 3.70–5.41 (m,
5H, 2H-50, H-40, H-30, H-20); 6.25 (d, 1H, H-10); 7.06–7.56 (m, 8H,
2C6H4); 10.33 (s, 1H, NH). C32H30ClN3O8S calcd.: C, 58.93%; H,
4.63%; N, 6.44%. Found: C, 59.10%; H, 4.80%; N, 6.48%.
Compound 8f: Yellow, mp 152 ꢀC, yield (34%). IR nmax=cmꢁ1 (KBr)
1
3313 (NH); 2225 (CN); 1756 (CO); 1658 (CO amide). H NMR: d 2.00–
2.16 (t, 9H, 3H3CO); 2.32 (s, 3H, CH3); 3.60–5.30 (m, 5H, 2H-50, H-40, H-
30, H-20); 6.00 (d, 1H, H-10); 7.11–7.70 (m, 8H, 2C6H4); 10.00 (s, 1H, NH).
C31H27Cl2N3O8S calcd.: C, 55.36%; H, 4.04%; N, 6.24%. Found: C,
55.40%; H, 4.05%; N, 6.25%.
Compound 8g: Yellow, mp 127 ꢀC, yield (66%). IR nmax=cmꢁ1 (KBr)
1
3324 (NH); 2225 (CN); 1752 (CO); 1655 (CO amide). H NMR: d 1.90–
2.15 (t, 9H, 3COCH3); 2.27 (s, 3H, CH3); 3.95 (s, 3H, OCH3); 4.18–5.40
(m, 5H, 2H-50, H-40, H-30, H-20); 6.10 (d, 1H, H-10); 6.60–7.70 (m, 9H,
C6H5,C6H4); 10.00 (s, 1H, NH). C32H31N3O9S calcd.: C, 60.65%; H,
4.93%; N, 6.63%. Found: C, 60.66%; H, 5.00%; N, 6.67%.
Compound 8h: Yellow, mp 132 ꢀC, yield (50%). IR nmax=cmꢁ1 (KBr)
3316 (NH); 2225 (CN); 1752 (CO); 1659 (CO of amide). 1H NMR: d 2.02–
2.10 (t, 9H, 3H3CO); 2.22 (s, 3H, CH3); 2.62 (s, 3H, CH3); 3.75 (s, 3H,
OCH3); 3.80–5.40 (m, 5H, 2H-50, H-40, H-30, H-20); 6.20 (d, 1H, H-10);
6.99–7.42 (m, 8H, 2C6H4); 10.30 (s, 1H, NH). C33H33N3O9S calcd.: C,
61.19%; H, 5.13%; N, 6.48%. Found: C, 61.25%; H, 5.15%; N, 6.52%.
Compound 8i: Yellow, mp 135 ꢀC, yield (27%). IR nmax=cmꢁ1
(KBr) 3314 (NH); 2225 (CN); 1752 (CO); 1682 (CO amide).

Direct Route to Novel 2-(b-D-Xylo- and Arabinopyranosylthio)
455
1H NMR: d 2.00–2.19 (t, 9H, 3H3CO); 2.43 (s, 3H, CH3); 3.90 (s, 3H,
OCH3); 4.00–5.20 (m, 5H, 2H-50, H-40, H-30, H-20); 6.00 (d, 1H, H-10);
6.99–7.42 (m, 8H, 2C6H4); 10.09 (s, 1H, NH). C32H30ClN3O9S calcd.: C,
57.52%; H, 4.52%; N, 6.28%. Found: C, 57.72%; H, 4.69%; N, 6.29%.
Compound 8j: Yellow, mp 140 ꢀC, yield (48.5%). IR nmax=cmꢁ1
(KBr) 3313 (NH); 2226 (CN); 1752 (CO); 1679 (CO amide). 1H NMR: d
2.02–2.07 (t, 9H, 3H3CO); 2.65 (s, 3H, CH3); 3.97–5.42 (m, 5H, 2H-50,
H-40, H-30, H-20); 6.21 (d, 1H, H-10); 7.07–7.57 (m, 9H, C6H4, C6H5);
10.44 (s, 1H, NH). C31H28ClN3O8S calcd.: C, 58.34%; H, 4.42%; N,
6.58%. Found: C, 58.38%; H, 4.42%; N, 6.62%.
Compound 8k: Yellow, mp 140 ꢀC, yield (58%). IR nmax=cm1 (KBr)
3314 (NH); 2225 (CN); 1752 (CO); 1657 (CO amide). 1H NMR: d
2.00–2.04 (t, 9H, 3H3CO); 2.22 (s, 3H, CH3); 2.64 (s, 3H, CH3); 3.90–
5.42 (m, 5H, 2H-50, H-40, H-30, H-20); 6.20 (d, 1H, H-10); 7.06–7.54 (m,
8H, 2C6H4); 10.34 (s, 1H, NH). C32H30ClN3O8S calcd.: C, 58.93%; H,
4.63%; N, 6.44%. Found: C, 59.10%; H, 4.79%; N, 6.47%.
Compound 8l: Yellow, mp 149 ꢀC, yield (30%). IR nmax=cmꢁ1 (KBr)
1
3311 (NH); 2226 (CN); 1751 (CO); 1683 (CO amide). H NMR: d 2.02–
2.09 (t, 9H, 3H3CO); 2.64 (s, 3H, CH3); 3.35–5.39 (m, 5H, 2H-50, H-40, H-
30, H-20); 6.22 (d, 1H, H-10); 7.33–7.52 (m, 8H, 2C6H4); 10.59 (s, 1H, NH).
13C NMR: 20.38–20.58 (3 CH3CO); 22.94 (CH3); 65.61–80.78 (C-50 C-40,
C-30, C-20, C-10); 105.26 (C-3); 114.27 (CN); 120.62–134.75 (2C6H4);
136.74 (C-5); 150.34 (C-4); 158.22 (C-6); 158.56 (C-S); 163.36 (CONH)
169.26–169.66 (3CO). C31H27Cl2N3O8S calcd.: C, 55.36%; H, 4.04%;
N, 6.24%. Found: C, 55.35%; H, 4.02%; N, 6.25%.
4-Aryl-3-cyano-6-metyl-2-(b-D-xylo- and Arabinopyranosylthio)-
pyridines (9a–l)
Dry gaseous ammonia was passed through a solution of protected glyco-
sides 8 (0.5 g) in dry methanol (20 ml) at room temperature for 10 min.
The mixture was stirred until the reaction was judged complete by
TLC (10–12 h) using CHCl3–MeOH, 9:1. The resulting mixture was then
concentrated under reduced pressure to afford a solid residue that was
crystallized from methanol.
Compound 9a: Brown, mp 133 ꢀC, yield (80%). IR nmax=cmꢁ1 (KBr)
3331–3400 (OH, NH); 2224 (CN); 1660 (CO amide). 1H NMR: d 2.00 (s,
3H, CH3); 2.40 (s, 3H, CH3); 3.90 (s, 3H, OCH3); 3.10–3.90 (m, 5H, H-50,
H-40, H-30, H-20); 5.00–5.60 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH); 6.00 (d,
1H, H-10); 6.90–7.70 (m, 8H, 2C6H4); 10.00 (s, 1H, NH). C26H25N3O6S
calcd.: C, 61.52%; H, 4.96%; N, 8.27%. Found: C, 61.55%; H, 5.00%;
N, 8.29%.

456
G. H. Elgemeie et al.
Compound 9b: Yellow, mp 144 ꢀC, yield (60%). IR nmax=cmꢁ1 (KBr)
1
3335–3420 (OH, NH); 2225 (CN); 1661 (CO amide). H NMR: d 2.22 (s,
3H, CH3); 2.59 (s, 3H, CH3); 3.76 (s, 3H, OCH3); 3.20–3.98 (m, 5H, H-50,
H-40, H-30, H-20); 5.08–5.57 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH); 5.79 (d, 1H,
H-10); 6.99–7.41 (m, 8H, 2C6H4); 10.27 (s, 1H, NH). C27H27N3O6S calcd.:
C, 62.17%; H, 5.21%; N, 8.05%. Found: C, 62.17%; H, 5.30%; N, 8.08%.
Compound 9c: Yellow, mp 156 ꢀC, yield (75%). IR nmax=cmꢁ1
(KBr) 3297–3390 (OH, NH); 2226 (CN); 1657 (CO of amide). 1H
NMR: d 2.20 (s, 3H, CH3); 3.80 (s, 3H, OCH3); 3.30–3.76 (m, 5H,
H-50, H-40, H-30, H-20); 5.00–5.60 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH);
5.99 (d, 1H, H-10); 7.02–7.78 (m, 8H, 2C6H4); 10.09 (s, 1H, NH).
C26H24ClN3O6S calcd.: C, 57.61%; H, 4.46%; N, 7.75%. Found: C,
57.72%; H, 4.66%; N, 7.77%.
Compound 9d: Yellow, mp 104 ꢀC, yield (75%). IR nmax=cmꢁ1 (KBr)
3294–3480 (OH, NH); 2226 (CN); 1656 (CO amide). 1H NMR: d 2.62 (s,
3H, CH3); 3.0–4.15 (m, 5H, 2H-50, H-40, H-30, H-20); 5.15–5.60 (m, 3H,
20ꢁOH, 30ꢁOH, 40ꢁOH); 5.79 (d, 1H, H-10); 7.02–7.56 (m, 9H, C6H5,
C6H4); 10.42 (s, 1H, NH). C25H22ClN3O5S calcd.: C, 58.64%; H,
4.33%; N, 8.20%. Found: C, 58.67%; H, 4.35%; N, 8.25%.
Compound 9e: Yellow, mp 146 ꢀC, yield (78%). IR nmax=cmꢁ1
(KBr) 3279–3400 (OH, NH); 2226.3 (CN); 1656 (CO amide). 1H
NMR: d 2.22 (s, 3H, CH3); 2.61 (s, 3H, CH3); 3.25–3.98 (m, 5H, 2H-
50, H-40, H-30, H-20); 5.15–5.60 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH); 5.79
(d, 1H, H-10); 7.03–7.56 (m, 8H, 2C6H4); 10.32 (s, 1H, NH).
C26H24ClN3O5S calcd.: C, 59.36%; H, 4.59%; N, 7.98%. Found: C,
59.38%; H, 4.61%; N, 8.00%.
Compound 9f: Yellow, mp 160 ꢀC, yield (59%). IR nmax=cmꢁ1 (KBr)
3277–3440 (OH, NH); 2225 (CN); 1657 (CO amide).1H NMR: d 2.40 (s,
3H, CH3); 3.20–3.70 (m, 5H, 2H-50, H-40, H-30, H-20); 5.10–5.70 (m, 3H,
20ꢁOH, 30ꢁOH, 40ꢁOH); 6.00 (d, 1H, H-10); 7.00–7.70 (m, 8H, 2C6H4);
10.32 (s, 1H, NH). C25H21Cl2N3O5S calcd.: C, 54.94%; H, 3.87%; N,
7.69%. Found: C, 54.87%; H, 4.07%; N, 7.68%.
Compound 9g: Brown, mp 107 ꢀC, yield (65%). IR nmax=cmꢁ1 (KBr)
3304–3470 (OH, NH); 2224 (CN); 1658 (CO amide). 1H NMR: d 2.50 (s,
3H, CH3); 3.20–3.88 (m, 5H, 2H-50, H-40, H-30, H-20); 4.00 (s, 3H, OCH3);
5.10–5.70 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH); 5.98 (d, 1H, H-10); 7.00–7.80
(m, 9H, C6H5, C6H4); 10.11 (s, 1H, NH). C26H25N3O6S calcd.: C,
61.52%; H, 4.96%; N, 8.27%. Found: C, 61.60%; H, 4.98%; N, 8.27%.
Compound 9h: Yellow, mp 118 ꢀC, yield (50%). IR nmax=cmꢁ1 (KBr)
3295–3450 (OH, NH); 2224 (CN); 1657 (CO amide). 1H NMR: d 2.22 (s,
3H, CH3); 2.57 (s, 3H, CH3); 3.35–3.80 (m, 5H, 2H-50, H-40, H-30, H-20);
3.85 (s, 3H, OCH3); 4.69–5.60 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH); 6.26 (d,
1H, H-10); 6.98–7.41 (m, 8H, 2C6H4); 10.24 (s, 1H, NH). C27H27N3O6S

Direct Route to Novel 2-(b-D-Xylo- and Arabinopyranosylthio)
457
calcd.: C, 62.17%; H, 5.21%; N, 8.05%. Found: C, 62.18%; H, 5.25%;
N, 8.10%.
Compound 9i: Brown, mp 92 ꢀC, yield (55%). IR nmax=cmꢁ1 (KBr)
3292–3470 (OH, NH); 2224 (CN); 1659 (CO amide).1H NMR: d 2.55
(s, 3H, CH3); 3.11–4.00 (m, 5H, 2H-50, H-40, H-30, H-20); 4.09 (s, 3H,
OCH3); 5.22–5.75 (m, 3H, 20ꢁOH, 30ꢁOH, 40ꢁOH); 5.80 (d, 1H,
H-10); 7.09–7.90 (m, 8H, 2C6H4); 10.11 (s, 1H, NH). C26H24ClN3O6S
calcd.: C, 57.61%; H, 4.46%; N, 7.75%. Found: C, 57.75%; H, 4.65%;
N, 7.72%.
Compound 9j: Yellow, mp 136 ꢀC, yield (70%). IR nmax=cmꢁ1 (KBr)
3297–3460 (OH, NH); 2226 (CN); 1658 (CO amide). 1H NMR: d 2.20 (s,
3H, CH3); 3.55–5.70 (m, 8H, 2H-50, H-40, H-30, H-2n; 20ꢁOH, 30ꢁOH,
40ꢁOH); 5.90 (d, 1H, H-10); 6.90–7.67 (m, 9H, C6H4,C6H4); 9.99 (s,
1H, NH). C25H22ClN3O5S calcd.: C, 58.64%; H, 4.33%; N, 8.20%.
Found: C, 58.65%; H, 4.34%; N, 8.22%.
Compound 9k: Yellow, mp 154 ꢀC, yield (75%). IR nmax=cmꢁ1 (KBr)
3269–2380 (OH, NH); 2224 (CN); 1653 (CO amide). 1H NMR: d 2.24 (s,
3H, CH3); 2.47 (s, 3H, CH3); 3.81–5.73 (m, 8H, 2H-50, H-40, H-30, H-20;
20ꢁOH, 30ꢁOH, 40ꢁOH); 5.94 (d, 1H, H-10); 6.92–7.42 (m, 8H, 2C6H4);
8.79 (s, 1H, NH). C26H24ClN3O5S calcd.: C, 59.36%; H, 4.59%; N,
7.98%. Found: C, 59.36%; H, 4.62%; N, 8.20%.
Compound 9l: Brown, mp 164 ꢀC, yield (65%). IR nmax=cmꢁ1 (KBr)
3425–3500 (OH, NH); 2224 (CN); 1655 (CO amide). 1H NMR: d 2.00 (s,
3H, CH3); 3.30–5.60 (m, 8H, 2H-50, H-40, H-30, H-20 20ꢁOH, 30ꢁOH,
40ꢁOH); 5.99 (d, 1H, H-10); 6.99–7.77 (m, 8H, 2C6H4); 9.00 (s, 1H,
NH). C25H21Cl2N3O5S calcd.: C, 54.94%; H, 3.87%; N, 7.69%. Found:
C, 54.87%; H, 4.05%; N, 7.69%.
6-Methyl-3-cyano-pyridine-2(1H)-thiones (10a–f)
A mixture of arylmethylenecyanothioacetamide 1 (0.01 mol) and 3-oxo-
N-arylbutanamides 1 (0.01 mol) was dissolved in ethanol (30 ml) contain-
ing piperidine (three drops). The mixture was refluxed for 1 h and then
allowed to cool to room temperature and acidified with cold dilute
hydrochloric acid. The resulting solid product was collected by filtration
and crystallized from the appropriate solvent.
Compound 10a: Yellow, mp 245–247 ꢀC, yield (85%). IR nmax=cmꢁ1
(KBr) 3450 (NH); 2215 (CN); 1640 (CO).
Compound 10b: Yellow, mp 289–291 ꢀC, yield (85%). IR nmax=cmꢁ1
(KBr) 3370 (NH); 2210 (CN); 1690 (CO).
Compound 10c: Yellow, mp 270–272 ꢀC, yield (80%). IR nmax=cmꢁ1
(KBr) 3300 (NH); 2215 (CN); 1660 (CO).

458
G. H. Elgemeie et al.
Compound 10d: Yellow, mp 265–267 ꢀC, yield (65%). IR nmax=cmꢁ1
(KBr) 3380 (NH); 2210 (CN); 1650 (CO).
Compound 10e: Yellow, mp 180 ꢀC, yield (60%). IR nmax=cmꢁ1
(KBr) 3390 (NH); 2210 (CN); 1670 (CO).
Compound 10f: Yellow, mp 240–242 ꢀC, yield (55%). IR nmax=cmꢁ1
(KBr) 3350 (NH); 2220 (CN); 1660 (CO).
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