Michael adducts of vinyl sulfones - Source for thiadiazoles, oxadiazoles and triazoles

Article abstract of DOI:10.1002/jhet.5570450613

(Chemical Equation Presented) A new and novel five membered heterocycles thiadiazoles, oxadiazoles and triazoles were prepared from methyl 4-arylsulfonyl-3-arylbutyrate and methyl 4-arylmethanesulfonyl-3-arylbutyrate.

Full text of DOI:10.1002/jhet.5570450613

Nov-Dec 2008
1633
Michael Adducts of Vinyl Sulfones – Source for Thiadiazoles,
Oxadiazoles and Triazoles
Venkatapuram Padmavathi,* Guda Dinneswara Reddy, Gali Sudhakar Reddy
Department of Chemistry, Sri Venkateswara University, Tirupati-517502, India
(Phone: +91-877-2249666-303: Fax: +91-877-2248499:
E mail: vkpuram2001@yahoo.com
Received March 21, 2008
N
N
N N
CO2CH3
Ar'
SH
SH
X
N
O
O
O
O
O
O
Ar
S
Ar
S
Ar
S
NH2
( )n
( )n
Ar'
( )n
Ar'
3/4
9/10 X = S
11/12 X = O
13/14
n = 0 (9,11,13); n = 1 (10,12,14)
A new and novel five membered heterocycles thiadiazoles, oxadiazoles and triazoles were prepared
from methyl 4-arylsulfonyl-3-arylbutyrate and methyl 4-arylmethanesulfonyl-3-arylbutyrate.
J. Heterocyclic Chem., 45, 1633 (2008).
INTRODUCTION
1750 for CO2Me and 1320-1340 and 1120-1150 cm-1 for
SO2. The H NMR spectrum of 3a displayed four double
1
Incorporation of heteroatoms in the carbon frame-work
to achieve the desired heterocyclic compounds is one of
the important aspects in the field of heterocycles. In fact,
the chemistry of heterocycles containing nitrogen and
sulfur has gained importance due to their varied
physiological action and diverse physicochemical
properties. The triazole nucleus has a broad spectrum of
antimicrobial activity [1]. Bis heterocyclic compounds
having both triazole and thiadiazine moieties possess
antiparasite activity [2]. The most frequently used
triazoles are fluconazole and itraconazole that display a
broad spectrum of antifungal activity and reduced toxicity
when compared with imidazole antifungals [3-8]. Besides,
2-mercapto-5-methyl-1,3,4-thiadiazole is an intermediate
for therapeutically useful antibiotic cefazolin [9].
Moreover, 1,3,4-oxadiazoles find wide usage as dyes,
photosensitive and electrical materials [10]. They also
exhibit broad spectrum of biological activity such as HIV
and antimicrobial [11,12]. In fact, for the last few years
we have been involved in the synthesis of a variety of
heterocyclic systems. Our continued interest in the field of
heterocycles led us to report a new class of five
membered heterocycles, thiadiazoles, oxadiazoles and
triazoles.
doublets at 2.71, 2.93 (C2-H), 3.13, 3.22 (C4-H), a
multiplet at 3.79-3.81 (C3-H) and a singlet at 3.60 (OCH3)
in addition to a multiplet in the region 7.16-7.35 ppm for
1
aromatic protons. The H NMR spectrum of 4a exhibited
signals almost in the same regions as in 3a. In addition to
this, a singlet was observed at 3.93 ppm due to methylene
protons flanked between aryl and sulfonyl groups.
Treatment of compounds 3 and 4 with hydrazine hydrate
gave the corresponding acid hydrazide, 4-arylsulfonyl-3-
arylbutanehydrazide (5) and 4-arylmethanesulfonyl-3-
arylbutanehydrazide (6), respectively. The IR spectra of 5
and 6 displayed absorption bands at 1650-1665 for amide
carbonyl and at 3325-3335 and 3215-3230 cm-1 for NH
and NH2 respectively in addition to the bands due to SO2.
The 1H NMR spectrum of 5a displayed four double
doublets at 2.68, 2.83 (C2-H), 3.04, 3.20 (C4-H) and a
multiplet at 3.72-3.76 ppm (C3-H). Similarly, 6a also
exhibited four double doublets at 2.71, 2.83 (C2-H), 3.17,
3.23 (C4-H) and a multiplet at 3.69-3.74 (C3-H) in
addition to a singlet at 4.33 ppm (Ph-CH2). Apart from
these, 5a and 6a exhibited broad signals in the regions
7.84-7.94 and 4.44-4.52 ppm for NH and NH2, which
disappeared on deuteration. The potassium dithio-
carbazate of the acid hydrazides, 7 and 8 were prepared
by treating 5 and 6 with carbon disulfide in the presence
potassium hydroxide under ultrasonic conditions. The
former compounds under refluxing in acetic acid cyclized
to 5-[2'-aryl-3'-(arylsulfonyl)propyl]-1,3,4-thiadiazole-2-
thiol (9) and 5-[2'-aryl-3'-(arylmethanesulfonyl)propyl]-
1,3,4-thiadiazole-2-thiol (10). On the other hand, acid
catalysed hydrolysis of 7 and 8 resulted in 5-[2'-aryl-3'-
(arylsulfonyl)propyl]-1,3,4-oxadiazole-2-thiol (11) and 5-
[2'-aryl-3'-(arylmethanesulfonyl)propyl]-1,3,4-oxadiazole-
2-thiol (12). Besides, 5-[2'-aryl-3'-(arylsulfonyl)propyl]-
RESULTS AND DISCUSSION
The Michael addition of dimethyl malonate to aryl
styryl sulfone (1) and benzyl styryl sulfone (2) in the
presence of Triton-B in toluene gave a product that was
identified as methyl 4-arylsulfonyl-3-arylbutyrate (3) and
methyl 4-arylmethanesulfonyl-3-arylbutyrate (4). This
shows that during the course of the reaction
decarboxylation also took place [13,14]. The IR spectra of
3 and 4 exhibited absorption bands in the regions 1735-

1634
V. Padmavathi, G. D. Reddy, G. S. Reddy
Vol 45
1,2,4-triazole-4-amino-3-thiol (13) and 5-[2'-aryl-3'-
(arylmethanesulfonyl)propyl]-1,2,4-triazole-4-amino-3-
thiol (14) were obtained by refluxing 7 and 8 with
hydrazine hydrate. The IR spectra of the compounds 9-14
displayed absorption bands in the regions 1620-1635 for
C=N, 2560-2584 cm-1 for SH besides bands due to SO2
group. In addition to these, compounds 13 and 14
exhibited a broad band at 3258-3280 cm-1 for NH2. The 1H
NMR spectra of compounds 9a-14a displayed a singlet in
the region 9.78-10.35 ppm for SH. Besides these, two sets
compounds 9-14 were further confirmed by 13C NMR
spectra.
CONCLUSION
The ester functionality in Michael adducts methyl 4-
arylsulfonyl-3-arylbutyrate (3) and methyl 4-arylmethane-
sulfonyl-3-arylbutyrate (4) is conveniently utilized to
develop thiadiazoles, oxadiazoles and triazoles adopting
simple and well-versed methodology.
Scheme 1
CO2CH3
Ar'
O
O
O
O
i
S
Ar
S
Ar
( )n
Ar'
( )n
3/4
1/2
ii
CONHNH2
Ar'
O
O
Ar
Ar
S
S
( )n
5/6
S
iii
CONHNHCS K +
O
O
( )n
Ar'
7/8
iv
v
vi
N
N
N
N
N
S
N
SH
SH
SH
O
N
O
O
O
O
O
O
S
Ar
S
Ar
Ar
S
NH2
Ar'
( )n
( )n
Ar'
( )n
Ar'
9/10
13/14
11/12
n = 0 (1,3,5,7,9,11,13)
n = 1 (2,4,6,8,10,12,14)
(i) DMM / Triton-B / Toluene
(ii) N2H4.H2O / Pyridine/ MeOH
(iii) CS2 / KOH / EtOH / ultrasonic
(iv) AcOH
(v) HCl / H2O
(vi) N2H4.H2O
Ar
Ph
Ph
Ph
4-ClPh
4-ClPh
Ar'
Ph
4-MePh
4-ClPh
Ph
a
b
c
d
e
4-ClPh
EXPERIMENTAL
of double doublets observed at 2.83, 2.96, 3.08, 3.24 in
9a, 2.89, 2.97, 3.09, 3.23 in 10a, 2.86, 3.01, 3.12, 3.23 in
11a, 2.81, 2.98, 3.14, 3.21 in 12a, 2.85, 2.97, 3.10, 3.24 in
13a and 2.82, 2.96, 3.04, 3.17 ppm in 14a were attributed
to C1'-H and C3'-H, respectively. A multiplet observed in
the region 4.21-4.26 in 9a, 4.20-4.27 in 10a, 4.22-4.27 in
11a, 4.16-4.22 in 12a, 4.25-4.36 in 13a and 4.18-4.22
ppm in 14a was due C2'-H. Apart from these, compounds
10a, 12a and 14a displayed a singlet at 4.28, 4.32 and
4.26 ppm due to benzylic protons. The compounds 13a
and 14a showed a broad singlet at 5.49-5.85 ppm for NH2,
which disappeared on deuteration. The structures of the
Melting points were determined in open capillaries on a Mel-
Temp apparatus and are uncorrected. The purity of the
compounds was checked by TLC (silica gel H, BDH, ethyl
acetate/hexane, 1:3). The IR spectra were recorded on a Thermo
Nicolet IR200 FT-IR spectrometer as KBr pellets and the wave
numbers were given in cm-1. The 1H NMR spectra were recorded
in CDCl3/DMSO-d6 on a Varian EM-360 spectrometer (300
MHz). The 13C NMR spectra were recorded in CDCl3/DMSO-d6
on a Varian VXR spectrometer operating at 75.5 MHz. All
chemical shifts are reported in ꢀ (ppm) using TMS as an internal
standard. The microanalyses were performed on a Perkin-Elmer

Nov-Dec 2008
Michael Adducts of Vinyl Sulfones – Source for Thiadiazoles, Oxadiazoles and Triazoles
1635
240C elemental analyzer. The starting compounds aryl styryl
sulfones (1) and benzyl styryl sulfones (2) were prepared by the
literature procedure [14,15].
CH2), 7.16-7.49 (m, 10H, phenyl protons); 13C nmr: ꢀ 36.3 (C-
3), 40.1 (C-2), 53.2 (OCH3), 55.1 (C-4), 58.2 (Ar-CH2), 172.9
(CO2Me), 125.2, 128.8, 129.4, 131.8, 132.9, 138.4 (aromatic
carbons); Anal. Calcd. for C18H20O4S: C, 65.04; H, 6.06. Found:
C, 65.15; H, 6.01.
Methyl 4-arylsulfonyl-3-arylbutyrate (3) and Methyl 4-
arylmethanesulfonyl-3-arylbutyrate (4): General Procedure.
To a solution of aryl styryl sulfone (1)/benzyl styryl sulfone (2)
(1 mmole) and dimethyl malonate (1.5 mmoles) in toluene (6
mL) was taken. A catalytic amount of Triton-B was added to the
contents of the flask and refluxed for 3-6 hours. The reaction
mixture was cooled and the solvent was removed under reduced
pressure. The syrupy substance obtained was solidified on
treatment with methanol or 2-propanol. The resultant compound
was purified by recrystallization from 2-propanol.
Methyl 4-phenylmethanesulfonyl-3-(4-methylphenyl)-
butyrate (4b). This compound was obtained as white solid, mp
107-109°; ir: CO 1735, SO2 1326, 1134 cm-1; 1H nmr: ꢀ 2.28 (s,
3H, Ar-CH3), 2.71 (dd, 1H, C2-H, J=7.8, 16.3 Hz), 2.88 (dd, 1H,
C2-H, J=6.0, 16.0 Hz), 3.14 (dd, 1H, C4-H, J=6.3, 14.0 Hz), 3.29
(dd, 1H, C4-H, J=6.6, 14.3 Hz), 3.59 (s, 3H, OCH3), 3.75-3.91
(m, 1H, C3-H), 3.96 (s, 2H, Ar-CH2), 7.23-7.56 (m, 9H, phenyl
protons); 13C nmr: ꢀ 21.8 (Ar-CH3), 35.7 (C-3), 40.9 (C-2), 54.6
(OCH3), 55.9 (C-4), 58.6 (Ar-CH2), 172.1 (CO2Me), 126.4,
128.0, 129.6, 132.8, 133.2, 139.0 (aromatic carbons).
Methyl 4-phenylsulfonyl-3-phenylbutyrate (3a). This
compound was obtained as white solid, mp 109-111°; ir: CO
1
1747, SO2 1342, 1139 cm-1; H nmr: ꢀ 2.71 (dd, 1H, C2-H,
Methyl 4-phenylmethanesulfonyl-3-(4-chlorophenyl)-
butyrate (4c). This compound was obtained as colorless
J=7.9, 15.8 Hz), 2.93 (dd, 1H, C2-H, J=6.1, 16.1 Hz), 3.13 (dd,
1H, C4-H, J=6.7, 13.9 Hz), 3.22 (dd, 1H, C4-H, J=6.4, 14.0 Hz),
3.60 (s, 3H, OCH3), 3.79-3.81 (m, 1H, C3-H), 7.16-7.35 (m,
10H, phenyl protons); 13C nmr: ꢀ 35.6 (C-3), 39.7 (C-2), 52.6
(OCH3), 55.9 (C-4), 172.6 (CO2Me), 125.5, 126.1, 127.8, 129.3,
132.7, 138.5 (aromatic carbons); Anal. Calcd. for C17H18O4S: C,
64.13; H, 5.70. Found: C, 64.01; H, 5.75.
1
needles, mp 118-120°; ir: CO 1744, SO2 1334, 1131 cm-1; H
nmr: ꢀ 2.76 (dd, 1H, C2-H, J=8.1, 16.5 Hz), 2.91 (dd, 1H, C2-H,
J=6.2, 16.2 Hz), 3.17 (dd, 1H, C4-H, J=6.1, 14.3 Hz), 3.34 (dd,
1H, C4-H, J=6.8, 14.5 Hz), 3.64 (s, 3H, OCH3), 3.72-3.89 (m,
1H, C3-H), 3.94 (s, 2H, Ar-CH2), 7.19-7.62 (m, 9H, phenyl
protons); 13C nmr: ꢀ 35.7 (C-3), 39.4 (C-2), 53.2 (OCH3), 55.1
(C-4), 57.6 (Ar-CH2), 172.9 (CO2Me), 125.2, 128.8, 129.9,
131.8, 132.9, 138.4 (aromatic carbons); Anal. Calcd. for
C18H19ClO4S: C, 58.93; H, 5.22. Found: C, 58.89; H, 5.17.
Methyl 4-(4-chlorophenylmethanesulfonyl)-3-phenyl-
butyrate (4d). This compound was obtained as white solid, mp
121-123°; ir: CO 1741, SO2 1329, 1141 cm-1.
Methyl 4-(4-chlorophenylmethanesulfonyl)-3-(4-chloro-
phenyl)butyrate (4e). This compound was obtained as white
solid, mp 115-117°; ir: CO 1738, SO2 1335, 1126 cm-1; 1H
nmr: ꢀ 2.71 (dd, 1H, C2-H, J=8.4, 16.0 Hz), 2.94 (dd, 1H, C2-H,
J=6.3, 16.2 Hz), 3.17 (dd, 1H, C4-H, J=6.9, 14.1 Hz), 3.28 (dd,
1H, C4-H, J=6.6, 14.1 Hz), 3.59 (s, 3H, OCH3), 3.75-3.83 (m,
1H, C3-H), 3.95 (s, 2H, Ar-CH2), 7.16-7.35 (m, 8H, phenyl
protons); 13C nmr: ꢀ 35.8 (C-3), 39.7 (C-2), 51.8 (OCH3), 56.2
(C-4), 58.9 (Ar-CH2), 171.3, (CO2Me), 125.7, 128.9, 129.2,
131.9, 133.6, 139.2 (aromatic carbons); Anal. Calcd. for
C18H18Cl2O4S: C, 53.87; H, 4.52. Found: C, 53.82; H, 4.47.
4-Arylsulfonyl-3-arylbutanehydrazide (5) and 4-Aryl-
methanesulfonyl-3-arylbutanehydrazide (6): General
Procedure. To a solution of methyl 4-arylsulfonyl-3-aryl-
butyrate (3)/methyl 4-arylmethanesulfonyl-3-arylbutyrate (4) (1
mmole) in absolute ethanol, hydrazine hydrate (4.5 mmoles) and
pyridine (0.4 mL) were added and stirred for 5-6 hours at room
temperature. The resultant solid was collected by filtration, dried
and recrystallized from ethanol.
Methyl 4-phenylsulfonyl-3-(4-methylphenyl)butyrate (3b).
This compound was obtained as white solid, mp 103-105°; ir:
1
CO 1735, SO2 1336, 1125 cm-1; H nmr: ꢀ 2.26 (s, 3H, Ar-
CH3), 2.75 (dd, 1H, C2-H, J=7.9, 16.4 Hz), 2.94 (dd, 1H, C2-H,
J=5.6, 16.5 Hz), 3.16 (dd, 1H, C4-H, J=7.1, 14.2 Hz), 3.27 (dd,
1H, C4-H, J=7.6, 14.7 Hz), 3.67 (s, 3H, OCH3), 3.73-3.84 (m,
1H, C3-H), 7.21-7.82 (m, 9H, phenyl protons); 13C nmr: ꢀ 20.3
(Ar-CH3), 36.1 (C-3), 38.2 (C-2), 52.9 (OCH3), 56.3 (C-4),
173.4 (CO2Me), 125.1, 126.8, 128.8, 129.3, 132.1, 138.4
(aromatic carbons); Anal. Calcd. for C18H20O4S: C, 65.04; H,
6.06. Found: C, 65.11; H, 5.59.
Methyl 4-phenylsulfonyl-3-(4-chlorophenyl)butyrate (3c).
This compound was obtained as white solid, mp 114-116°; ir:
CO 1744, SO2 1330, 1145 cm-1.
Methyl 4-(4-chlorophenylsulfonyl)-3-phenylbutyrate (3d).
This compound was obtained as colorless crystals, mp 119-121°;
1
ir: CO 1744, SO2 1324, 1136 cm-1; H nmr: ꢀ 2.62 (dd, 1H, C2-
H, J=7.2, 15.9 Hz), 2.95 (dd, 1H, C2-H, J=6.7, 16.4 Hz), 3.20
(dd, 1H, C4-H, J=6.6, 14.1 Hz), 3.25 (dd, 1H, C4-H, J=7.3, 14.6
Hz), 3.65 (s, 3H, OCH3), 3.84-3.95 (m, 1H, C3-H), 7.19-7.45 (m,
9H, phenyl protons); 13C nmr: ꢀ 36.3 (C-3), 41.8 (C-2), 52.9
(OCH3), 54.8 (C-4), 173.2 (CO2Me), 125.1, 126.4, 127.2, 128.0,
129.9, 130.6, 133.7, 138.4 (aromatic carbons).
Methyl 4-(4-chlorophenylsulfonyl)-3-(4-chlorophenyl)-
butyrate (3e). This compound was obtained as white solid, mp
1
112-114°; ir: CO 1741, SO2 1333, 1142 cm-1; H nmr: ꢀ 2.74
4-Phenylsulfonyl-3-phenylbutanehydrazide (5a). This
compound was obtained as white solid, mp 141-143°; ir: NH
(dd, 1H, C2-H, J=8.1, 16.3 Hz), 2.86 (dd, 1H, C2-H, J=6.4, 16.2
Hz), 3.24 (dd, 1H, C4-H, J=6.8, 14.8 Hz), 3.29 (dd, 1H, C4-H,
J=7.5, 14.8 Hz), 3.59 (s, 3H, OCH3), 3.96-3.98 (m, 1H, C3-H),
7.21-7.46 (m, 8H, phenyl protons); 13C nmr: ꢀ 36.9 (C-3), 38.6
(C-2), 53.4 (OCH3), 51.9 (C-4), 173.4 (CO2Me), 126.3, 128.4,
128.9, 129.7, 132.5, 139.8 (aromatic carbons); Anal. Calcd. for
C17H16Cl2O4S: C, 52.72; H, 4.16. Found: C, 52.65; H, 4.10.
Methyl 4-phenylmethanesulfonyl-3-phenylbutyrate (4a).
This compound was obtained as white crystals, mp 99-101°; ir:
1
3330, NH2 3223, CO 1658, SO2 1330, 1126 cm-1; H nmr: ꢀ
2.68 (dd, 1H, C2-H, J=8.7, 16.7 Hz), 2.83 (dd, 1H, C2-H, J=6.5,
16.2 Hz), 3.04 (dd, 1H, C4-H, J=5.2, 15.0 Hz), 3.20 (dd, 1H, C4-
H, J=7.5, 14.8 Hz), 3.72-3.76 (m, 1H, C3-H), 4.44 (bs, 2H, NH2),
7.07-7.72 (m, 10H, phenyl protons), 7.84 (bs, 1H, NH); 13C
nmr: ꢀ 36.2 (C-3), 39.4 (C-2), 55.7 (C-4), 165.4 (CONH),
124.2, 126.9, 127.7, 128.3, 130.7, 131.4, 135.9, 139.5 (aromatic
carbons); Anal. Calcd. for C16H18N2O3S: C, 60.36; H, 5.70; N,
8.80. Found: C, 60.30; H, 5.72; N, 8.84.
1
CO 1747, SO2 1322, 1140 cm-1; H nmr: ꢀ 2.78 (dd, 1H, C2-H,
4-Phenylsulfonyl-3-(4-methylphenyl)butanehydrazide (5b).
This compound was obtained as colorless crystals, mp 147-149°;
J=8.3, 16.1 Hz), 2.92 (dd, 1H, C2-H, J=6.1, 16.2 Hz), 3.18 (dd,
1H, C4-H, J=6.6, 14.2 Hz), 3.26 (dd, 1H, C4-H, J=6.4, 14.4 Hz),
3.64 (s, 3H, OCH3), 3.78-3.88 (m, 1H, C3-H), 3.93 (s, 2H, Ar-
1
ir: NH 3328, NH2 3215, CO 1665, SO2 1320, 1132 cm-1; H

1636
V. Padmavathi, G. D. Reddy, G. S. Reddy
Vol 45
nmr: ꢀ 2.23 (s, 3H, Ar-CH3), 2.74 (dd, 1H, C2-H, J=8.4, 16.6
Hz), 2.94 (dd, 1H, C2-H, J=6.3, 16.0 Hz), 3.06 (dd, 1H, C4-H,
J=6.4, 14.9 Hz), 3.23 (dd, 1H, C4-H, J=7.4, 14.9 Hz), 3.74-3.79
(m, 1H, C3-H), 4.46 (bs, 2H, NH2), 7.06-7.53 (m, 9H, phenyl
protons), 7.72 (bs, 1H, NH); 13C nmr: ꢀ 21.6 (Ar-CH3), 36.5 (C-
3), 38.9 (C-2), 55.3 (C-4), 166.2 (CONH), 125.8, 126.8, 127.4,
128.3, 130.1, 133.7, 136.6, 139.4 (aromatic carbons); Anal.
Calcd. for C17H20N2O3S: C, 61.42; H, 6.06; N, 8.43. Found: C,
61.45; H, 6.03; N, 8.49.
4-Phenylsulfonyl-3-(4-chlorophenyl)butanehydrazide (5c).
This compound was obtained as white solid, mp 135-137°; ir:
NH 3335, NH2 3219, CO 1654, SO2 1335, 1120 cm-1.
4-(4-Chlorophenyl)sulfonyl-3-phenylbutanehydrazide
(5d). This compound was obtained as white solid, mp 129-131°;
ir: NH 3327, NH2 3224, CO 1660, SO2 1325, 1141 cm-1; Anal.
Calcd. for C16H17ClN2O3S: C, 54.46; H, 4.86; N, 7.94. Found: C,
54.51; H, 4.90; N, 7.85.
phenyl protons), 7.86 (bs, 1H, NH); 13C nmr: ꢀ 37.6 (C-3), 39.8
(C-2), 54.3 (C-4), 58.7 (Ar-CH2), 165.5 (CONH), 125.8, 126.7,
128.6, 129.5, 132.4, 137.8, 140.5 (aromatic carbons).
4-(4-Chlorophenylmethanesulfonyl)-3-(4-chlorophenyl)-
butanehydrazide (6e). This compound was obtained as white
solid, mp 147-149°; ir: NH 3326, NH2 3225, CO 1650, SO2
1338, 1144 cm-1; Anal. Calcd. for C17H18Cl2N2O3S: C, 50.88; H,
4.52; N, 6.98. Found: C, 50.94; H, 4.55; N, 6.93.
Potassium (3-aryl-4-arylsulfonyl-1-butanoyl)hydrazine-N'-
carbodithioate (7) and Potassium (3-aryl-4-arylmethane-
sulfonyl-1-butanoyl)hydrazine-N'-carbodithioate (8):
General procedure. To a mixture of potassium hydroxide (2
mmoles) and 4-arylsulfonyl-3-arylbutanehydrazide (5)/4-
arylmethanesulfonyl-3-arylbutanehydrazide (6) (1 mmole) in
absolute ethanol (5 mL), carbon disulfide (4 mmoles) was added
and sonicated for 10-12 hours. The separated solid was collected
by filtration and dried.
4-(4-Chlorophenyl)sulfonyl-3-(4-chlorophenyl)butane-
hydrazide (5e). This compound was obtained as white solid, mp
144-146°; ir: NH 3334, NH2 3220, CO 1656, SO2 1334, 1128
5-[2'-Aryl-3'-(arylsulfonyl)propyl]-1,3,4-thiadiazole-2-thiol
(9) and 5-[2'-Aryl-3'-(arylmethanesulfonyl)propyl]-1,3,4-
thiadiazole-2-thiol (10): General procedure. A mixture of
potassium (3-aryl-4-arylsulfonyl-1-butanoyl)hydrazine-N'-
carbodithioate (7)/ potassium (3-aryl-4-arylmethanesulfonyl-1-
butanoyl)hydrazine-N'-carbodithioate (8) (1 mmole) and acetic
acid (4 mL) were refluxed for 18-24 hours. The contents of the
flask were cooled and poured into crushed ice. The solid
obtained was collected by filtration, dried and recrystallized
from 2-propanol.
1
cm-1; H nmr: ꢀ 2.74 (dd, 1H, C2-H, J=8.1, 16.4 Hz), 2.87 (dd,
1H, C2-H, J=5.7, 15.8 Hz), 3.26 (dd, 1H, C4-H, J=6.8, 14.6 Hz),
3.34 (dd, 1H, C4-H, J=7.0, 14.7 Hz), 3.74-3.82 (m, 1H, C3-H),
4.58 (bs, 2H, NH2), 7.15-7.47 (m, 8H, phenyl protons), 7.81 (bs,
1H, NH); 13C nmr: ꢀ 35.9 (C-3), 39.1 (C-2), 55.8 (C-4), 166.5
(CONH), 128.7, 129.4, 131.6, 132.6, 133.8, 134.9, 136.0, 139.4
(aromatic carbons).
4-Phenylmethanesulfonyl-3-phenylbutanehydrazide (6a).
This compound was obtained as white solid, mp 132-134°; ir
NH 3330, NH2 3218, CO 1662, SO2 1337, 1134 cm-1; 1H nmr: ꢀ
2.71 (dd, 1H, C2-H, J=8.2, 16.1 Hz), 2.83 (dd, 1H, C2-H, J=6.3,
16.1 Hz), 3.17 (dd, 1H, C4-H, J=6.7, 14.8 Hz), 3.23 (dd, 1H, C4-
H, J=7.1, 14.9 Hz), 3.69-3.74 (m, 1H, C3-H), 4.52 (bs, 2H, NH2),
4.33 (s, 2H, Ar-CH2),7.11-7.48 (m, 10H, phenyl protons), 7.94
(bs, 1H, NH); 13C nmr: ꢀ 37.8 (C-3), 40.4 (C-2), 53.8 (C-4),
59.5 (Ar-CH2), 165.7 (CONH), 126.5, 127.6, 128.9, 129.4,
130.7, 131.3, 139.4 (aromatic carbons); Anal. Calcd. for
C17H20N2O3S: C, 61.42; H, 6.06; N, 8.43. Found: C, 61.34; H,
6.10; N, 8.47.
5-[2'-Phenyl-3'-(phenylsulfonyl)propyl]-1,3,4-thiadiazole-
2-thiol (9a). This compound was obtained as white solid, mp
1
149-151°; ir: SH 2580, CN 1632, SO2 1320, 1144 cm-1; H
nmr: ꢀ 2.83 (dd, 1H, C1ꢁ-H, J=7.8, 15.7 Hz), 2.96 (dd, 1H, C1ꢁ-
H, J=6.5, 16.2 Hz), 3.08 (dd, 1H, C3ꢁ-H, J=5.9, 14.5 Hz), 3.24
(dd, 1H, C3ꢁ-H, J=6.3, 14.9 Hz), 4.21-4.26 (m, 1H, C2ꢁ-H), 7.09-
7.54 (m, 10H, phenyl protons), 10.26 (s, 1H, SH); 13C nmr: ꢀ
38.5 (C-2ꢁ), 43.2 (C-1ꢁ), 55.7 (C-3ꢁ), 166.5 (C-2), 168.3 (C-5),
123.5, 125.2, 126.8, 128.1, 129.7, 132.6, 137.8, 139.4 (aromatic
carbons); Anal. Calcd. for C17H16N2O2S3: C, 54.23; H, 4.28; N,
7.44. Found: C, 54.18; H, 4.30; N, 7.49.
5-[2'-(4-Methylphenyl)-3'-(phenylsulfonyl)propyl]-1,3,4-
thiadiazole-2-thiol (9b). This compound was obtained as white
solid, mp 157-159°; ir: SH 2584, CN 1636, SO2 1324, 1147
cm-1.
4-Phenylmethanesulfonyl-3-(4-methylphenyl)butane-
hydrazide (6b). This compound was obtained as white solid, mp
127-129°; ir: NH 3335, NH2 3212, CO 1655, SO2 1327, 1123
cm-1; 1H nmr: ꢀ 2.28 (s, 3H, Ar-CH3), 2.74 (dd, 1H, C2-H,
J=8.4, 16.6 Hz), 2.90 (dd, 1H, C2-H, J=6.6, 16.4 Hz), 3.06 (dd,
1H, C4-H, J=7.3, 14.8 Hz), 3.26 (dd, 1H, C4-H, J=9.4, 14.9 Hz),
3.72-3.76 (m, 1H, C3-H), 4.48 (bs, 2H, NH2), 4.37 (s, 2H, Ar-
5-[2'-(4-Chlorophenyl)-3'-(phenylsulfonyl)propyl]-1,3,4-
thiadiazole-2-thiol (9c). This compound was obtained as
colorless needles, mp 164-166°; ir: SH 2582, CN 1638, SO2
1
1322, 1150 cm-1; H nmr: ꢀ 2.87 (dd, 1H, C1ꢁ-H, J=7.7, 15.9
CH2), 7.02-7.35 (m, 9H, phenyl protons), 7.88 (bs, 1H, NH); 13
C
Hz), 3.02 (dd, 1H, C1ꢁ-H, J=6.3, 16.2 Hz), 3.14 (dd, 1H, C3ꢁ-H,
J=7.0, 14.0 Hz), 3.31 (dd, 1H, C3ꢁ-H, J=6.4, 14.9 Hz), 4.18-4.23
(m, 1H, C2ꢁ-H), 7.02-7.62 (m, 9H, phenyl protons), 10.35 (s, 1H,
SH); 13C nmr: ꢀ 39.2 (C-2ꢁ), 43.5 (C-1ꢁ), 55.8 (C-3ꢁ), 166.7 (C-
2), 168.0 (C-5), 128.8, 129.3, 129.7, 130.8, 131.1, 132.3, 133.6,
138.2 (aromatic carbons); Anal. Calcd. for C17H15ClN2O2S3: C,
49.68; H, 3.68; N, 6.82. Found: C, 49.71; H, 3.71; N, 6.74.
5-[2'-Phenyl-3'-(4-chlorophenylsulfonyl)propyl]-1,3,4-thia-
diazole-2-thiol (9d). This compound was obtained as white
solid, mp 141-143°; ir: SH 2578, CN 1635, SO2 1335, 1138
cm-1.
5-[2'-(4-Chlorophenyl)-3'-(4-chlorophenylsulfonyl)propyl]-
1,3,4-thiadiazole-2-thiol (9e). This compound was obtained as
white solid, mp 158-160°; ir: SH 2570, CN 1628, SO2 1332,
1125 cm-1; 1H nmr: ꢀ 2.91 (dd, 1H, C1ꢁ-H, J=7.6, 15.5 Hz), 3.04
(dd, 1H, C1ꢁ-H, J=6.1, 16.7 Hz), 3.12 (dd, 1H, C3ꢁ-H, J=6.9, 14.6
nmr: ꢀ 20.6 (Ar-CH3), 37.4 (C-3), 40.7 (C-2), 53.5 (C-4), 58.9
(Ar-CH2), 166.2 (CONH), 125.8, 128.4, 128.8, 129.8, 131.4,
133.5, 138.7 (aromatic carbons).
4-Phenylmethanesulfonyl-3-(4-chlorophenyl)butanehydra-
zide (6c). This compound was obtained as white solid, mp 142-
144°; ir: NH 3331, NH2 3221, CO 1652, SO2 1332, 1143 cm-1;
Anal. Calcd. for C17H19ClN2O3S: C, 55.66; H, 5.22; N, 7.64.
Found: C, 55.70; H, 5.26; N, 7.69.
4-(4-Chlorophenylmethanesulfonyl)-3-phenylbutane-
hydrazide (6d). This compound was obtained as white solid, mp
137-139°; ir: NH 3328, NH2 3228, CO 1657, SO2 1337, 1142
1
cm-1; H nmr: ꢀ 2.75 (dd, 1H, C2-H, J=7.5, 16.8 Hz), 2.95 (dd,
1H, C2-H, J=6.3, 16.2 Hz), 3.18 (dd, 1H, C4-H, J=7.0, 15.0 Hz),
3.28 (dd, 1H, C4-H, J=6.7, 14.8 Hz), 3.75-3.82 (m, 1H, C3-H),
4.57 (bs, 2H, NH2), 4.36 (s, 2H, Ar-CH2), 7.08-7.47 (m, 9H,

Nov-Dec 2008
Michael Adducts of Vinyl Sulfones – Source for Thiadiazoles, Oxadiazoles and Triazoles
1637
1
Hz), 3.27 (dd, 1H, C3ꢀ-H, J=6.7, 14.9 Hz), 4.21-4.27 (m, 1H,
C2ꢀ-H), 7.11-7.74 (m, 8H, phenyl protons), 10.31 (s, 1H, SH);
13C nmr: ꢁ 39.6 (C-2ꢀ), 43.9 (C-1ꢀ), 56.4 (C-3ꢀ), 166.8 (C-2),
168.2 (C-5), 128.7, 129.3, 129.9, 130.6, 131.5, 131.8, 134.3,
139.4 (aromatic carbons); Anal. Calcd. for C17H14Cl2N2O2S3: C,
45.84; H, 3.17; N, 6.29. Found: C, 45.78; H, 3.20; N, 6.24.
5-[2'-Phenyl-3'-(phenylmethanesulfonyl)propyl]-1,3,4-
thiadiazole-2-thiol (10a). This compound was obtained as white
solid, mp 145-147°; ir: SH 2583, CN 1633, SO2 1331, 1138
mp 184-186°; ir: SH 2562, CN 1625, SO2 1340, 1130 cm-1; H
nmr: ꢁ 2.86 (dd, 1H, C1ꢀ-H, J=7.5, 16.8 Hz), 3.01 (dd, 1H, C1ꢀ-
H, J=6.2, 16.5 Hz), 3.12 (dd, 1H, C3ꢀ-H, J=6.5, 14.4 Hz), 3.23
(dd, 1H, C3ꢀ-H, J=6.7, 14.1 Hz), 4.22-4.27 (m, 1H, C2ꢀ-H), 7.11-
7.84 (m, 10H, phenyl protons), 9.89 (s, 1H, SH); 13C nmr: ꢁ
38.8 (C-2ꢀ), 44.2 (C-1ꢀ), 56.3 (C-3ꢀ), 163.3 (C-2), 165.8 (C-5),
124.6, 125.5, 127.1, 128.9, 130.4, 133.3, 137.1, 139.5 (aromatic
carbons); Anal. Calcd. for C17H16N2O3S2: C, 56.65; H, 4.47; N,
7.77. Found: C, 56.61; H, 4.45; N, 7.83.
5-[2'-(4-Methylphenyl)-3'-(phenylsulfonyl)propyl]-1,3,4-
oxadiazole-2-thiol (11b). This compound was obtained as white
solid, mp 179-181°; ir: SH 2564, CN 1628, SO2 1338, 1135
cm-1; H nmr: ꢁ 2.29 (s, 3H, Ar-CH3), 2.88 (dd, 1H, C1ꢀ-H,
J=7.9, 16.3 Hz), 2.93 (dd, 1H, C1ꢀ-H, J=6.4, 16.3 Hz), 3.08 (dd,
1H, C3ꢀ-H, J=6.8, 15.0 Hz), 3.21 (dd, 1H, C3ꢀ-H, J=6.3, 14.8
Hz), 4.22-4.26 (m, 1H, C2ꢀ-H), 7.08-7.93 (m, 9H, phenyl
protons), 9.98 (s, 1H, SH); 13C nmr: ꢁ 21.6 (Ar-CH3), 38.2 (C-
2ꢀ), 43.6 (C-1ꢀ), 55.5 (C-3ꢀ), 164.2 (C-2), 166.6 (C-5), 125.9,
126.5, 126.9, 128.6, 129.8, 131.7, 138.3, 139.6 (aromatic
carbons); Anal. Calcd. for C18H18N2O3S2: C, 57.73; H, 4.84; N,
7.48. Found: C, 57.77; H, 4.86; N, 7.52.
5-[2'-(4-Chlorophenyl)-3'-(phenylsulfonyl)propyl]-1,3,4-
oxadiazole-2-thiol (11c). This compound was obtained as white
solid, mp 168-170°; ir: SH 2572, CN 1632, SO2 1330, 1132
cm-1.
1
cm-1; H nmr: ꢁ 2.89 (dd, 1H, C1ꢀ-H, J=8.3, 15.8 Hz), 2.97 (dd,
1H, C1ꢀ-H, J=6.2, 16.7 Hz), 3.09 (dd, 1H, C3ꢀ-H, J=6.6, 14.9
Hz), 3.23 (dd, 1H, C3ꢀ-H, J=7.0, 14.1 Hz), 4.20-4.27 (m, 1H,
C2ꢀ-H), 4.28 (s, 2H, Ar-CH2), 7.00-7.78 (m, 10H, phenyl
protons), 10.29 (s, 1H, SH); 13C nmr: ꢁ 38.4 (C-2ꢀ), 44.2 (C-1ꢀ),
54.9 (C-3ꢀ), 58.1 (Ar-CH2), 165.7 (C-2), 168.6 (C-5), 125.7,
126.9, 129.2, 130.4, 131.5, 133.7, 135.4, 139.9 (aromatic
carbons); Anal. Calcd. for C18H18N2O2S3: C, 55.36; H, 4.65; N,
7.17. Found: C, 55.30; H, 4.64; N, 7.23.
5-[2'-(4-Methylphenyl)-3'-(phenylmethanesulfonyl)propyl]-
1,3,4-thiadiazole-2-thiol (10b). This compound was obtained as
colorless crystals, mp 139-141°; ir: SH 2561, CN 1626, SO2
1333, 1141 cm-1; 1H nmr: ꢁ 2.27 (s, 3H, Ar-CH3), 2.88 (dd, 1H,
C1ꢀ-H, J=8.0, 16.2 Hz), 2.94 (dd, 1H, C1ꢀ-H, J=5.9, 16.5 Hz),
3.07 (dd, 1H, C3ꢀ-H, J=6.8, 14.4 Hz), 3.18 (dd, 1H, C3ꢀ-H, J=6.5,
14.7 Hz), 4.17-4.23 (m, 1H, C2ꢀ-H), 4.24 (s, 2H, Ar-CH2), 6.96-
7.54 (m, 9H, phenyl protons), 10.22 (s, 1H, SH); 13C nmr: ꢁ
21.2 (Ar-CH3), 38.1 (C-2ꢀ), 44.4 (C-1ꢀ), 54.6 (C-3ꢀ), 59.6 (Ar-
CH2), 166.3 (C-2), 168.2 (C-5), 124.1, 125.6, 127.3, 129.4,
132.5, 134.5, 135.8, 138.2 (aromatic carbons); Anal. Calcd. for
C19H20N2O2S3: C, 56.41; H, 4.98; N, 6.92. Found: C, 56.38; H,
4.93; N, 6.98.
1
5-[2'-Phenyl-3'-(4-chlorophenylsulfonyl)propyl]-1,3,4-oxa-
diazole-2-thiol (11d). This compound was obtained as white
solid, mp 188-190°; ir: SH 2586, CN 1623, SO2 1336, 1128
cm-1; H nmr: ꢁ 2.69 (dd, 1H, C1ꢀ-H, J=8.3, 15.8 Hz), 2.88 (dd,
1
1H, C1ꢀ-H, J=5.8, 15.9 Hz), 3.10 (dd, 1H, C3ꢀ-H, J=6.6, 14.5
Hz), 3.21 (dd, 1H, C3ꢀ-H, J=6.8, 14.4 Hz), 4.21-4.26 (m, 1H,
5-[2'-(4-Chlorophenyl)-3'-(phenylmethanesulfonyl)propyl]-
1,3,4-thiadiazole-2-thiol (10c). This compound was obtained as
white solid, mp 151-153°; ir: SH 2562, CN 1629, SO2 1337,
1128 cm-1.
C2ꢀ-H), 7.14-7.84 (m, 9H, phenyl protons), 9.78 (s, 1H, SH); 13
C
nmr: ꢁ 38.9 (C-2ꢀ), 44.1 (C-1ꢀ), 55.9 (C-3ꢀ), 163.3 (C-2), 165.8
(C-5), 125.2, 126.4, 127.3, 129.5, 131.8, 131.9, 133.5, 140.3
(aromatic carbons); Anal. Calcd. for C17H15ClN2O3S2: C, 51.71;
H, 3.83; N, 7.09. Found: C, 51.68; H, 3.79; N, 7.14.
5-[2'-(4-Chlorophenyl)-3'-(4-chlorophenylsulfonyl)propyl]-
1,3,4-oxadiazole-2-thiol (11e). This compound was obtained as
white solid, mp 194-196°; ir: SH 2564, CN 1626, SO2 1335,
1120 cm-1.
5-[2'-Phenyl-3'-(phenylmethanesulfonyl)propyl]-1,3,4-oxa-
diazole-2-thiol (12a). This compound was obtained as white
crystals, mp 177-179°; ir: SH 2569, CN 1630, SO2 1334, 1130
cm-1; H nmr: ꢁ 2.81 (dd, 1H, C1ꢀ-H, J=8.1, 16.1 Hz), 2.98 (dd,
1H, C1ꢀ-H, J=6.4, 16.6 Hz), 3.14 (dd, 1H, C3ꢀ-H, J=6.2 14.4 Hz),
3.21 (dd, 1H, C3ꢀ-H, J=6.5, 14.7 Hz), 4.16-4.22 (m, 1H, C2ꢀ-H),
4.32 (s, 2H, Ar-CH2), 6.96-7.44 (m, 10H, phenyl protons), 10.26
(s, 1H, SH); 13C nmr: ꢁ 38.2 (C-2ꢀ), 45.4 (C-1ꢀ), 56.2 (C-3ꢀ),
59.8 (Ar-CH2), 160.7 (C-2), 168.3 (C-5), 125.7, 126.4, 127.1,
127.8, 128.6, 132.5, 137.3, 138.9 (aromatic carbons); Anal.
Calcd. for C18H18N2O3S2: C, 57.73; H, 4.84; N, 7.48. Found: C,
57.70; H, 4.80; N, 7.44.
5-[2'-(4-Methylphenyl)-3'-(phenylmethanesulfonyl)propyl]-
1,3,4-oxadiazole-2-thiol (12b). This compound was obtained as
white solid, mp 183-185°; ir: SH 2560, CN 1623, SO2 1328,
1146 cm-1.
5-[2'-(4-Chlorophenyl)-3'-(phenylmethanesulfonyl)propyl]-
1,3,4-oxadiazole-2-thiol (12c). This compound was obtained as
white solid, mp 159-161°; ir: SH 2580, CN 1627, SO2 1328,
1134 cm-1; 1H nmr: ꢁ 2.83 (dd, 1H, C1ꢀ-H, J=7.9, 15.8 Hz), 2.96
(dd, 1H, C1ꢀ-H, J=6.0, 16.2 Hz), 3.07 (dd, 1H, C3ꢀ-H, J=6.5, 14.4
Hz), 3.22 (dd, 1H, C3ꢀ-H, J=6.8, 14.6 Hz), 4.18-4.22 (m, 1H,
5-[2'-Phenyl-3'-(4-chlorophenylmethanesulfonyl)propyl]-
1,3,4-thiadiazole-2-thiol (10d). This compound was obtained as
white solid, mp 148-150°; ir: SH 2564, CN 1632, SO2 1331,
1145 cm-1; 1H nmr: ꢁ 2.95 (dd, 1H, C1ꢀ-H, J=8.4, 16.0 Hz), 3.05
(dd, 1H, C1ꢀ-H, J=6.6, 16.5 Hz), 3.11 (dd, 1H, C3ꢀ-H, J=6.1, 14.3
Hz), 3.25 (dd, 1H, C3ꢀ-H, J=7.2, 14.8 Hz), 4.20-4.25 (m, 1H,
C2ꢀ-H), 4.23 (s, 2H, Ar-CH2), 7.02-7.60 (m, 9H, phenyl protons),
10.29 (s, 1H, SH); 13C nmr: ꢁ 37.6 (C-2ꢀ), 44.1 (C-1ꢀ), 55.5 (C-
3ꢀ), 59.2 (Ar-CH2), 166.5 (C-2), 168.9 (C-5), 124.6, 125.5,
126.9, 127.6, 128.4, 131.7, 136.3, 139.9 (aromatic carbons);
Anal. Calcd. for C18H17ClN2O2S3: C, 50.87; H, 4.03; N, 6.59.
Found: C, 50.90; H, 4.05; N, 6.63.
5-[2'-(4-Chlorophenyl)-3'-(4-chlorophenylmethanesulfonyl)-
propyl]-1,3,4-thiadiazole-2-thiol (10e). This compound was
obtained as white solid, mp 159-161°; ir: SH 2578, CN 1621,
SO2 1338, 1142 cm-1.
5-[2'-Aryl-3'-(arylsulfonyl)propyl]-1,3,4-oxadiazole-2-thiol
(11) and 5-[2'-Aryl-3'-(arylmethanesulfonyl)propyl]-1,3,4-
oxadiazole-2-thiol (12): General procedure. Potassium
(3-aryl-4-arylsulfonyl-1-butanoyl)hydrazine-N'-carbodithioate
(7)/potassium (3-aryl-4-arylmethanesulfonyl-1-butanoyl)hydra-
zine-N'-carbodithioate (8) (1 mmole) was dissolved in water (6
mL) and acidified with conc. HCl (1-2 mL). The regenerated
solid was collected by filtration, dried and purified by
recrystallization from 2-propanol.
1
5-[2'-Phenyl-3'-(phenylsulfonyl)propyl]-1,3,4-oxadiazole-
2-thiol (11a). This compound was obtained as colorless crystals,

1638
V. Padmavathi, G. D. Reddy, G. S. Reddy
Vol 45
C2ꢀ-H), 4.27 (s, 2H, Ar-CH2), 7.12-7.88 (m, 9H, phenyl protons),
10.22 (s, 1H, SH); 13C nmr: ꢁ 39.5 (C-2ꢀ), 44.9 (C-1ꢀ), 55.8 (C-
3ꢀ), 57.6 (Ar-CH2), 161.8 (C-2), 170.1 (C-5), 124.9, 125.6,
126.3, 129.4, 130.1, 132.7, 138.4, 140.5 (aromatic carbons);
Anal. Calcd. for C18H17ClN2O3S2: C, 52.87; H, 4.19; N, 6.85.
Found: C, 52.91; H, 4.15; N, 6.90.
5-[2'-Phenyl-3'-(4-chlorophenylmethanesulfonyl)propyl]-
1,3,4-oxadiazole-2-thiol (12d). This compound was obtained as
white solid, mp 165-167°; ir: SH 2574, CN 1635, SO2 1325,
1137 cm-1.
white solid, mp 222-224°; ir: NH2 3260, SH 2581, CN 1627,
SO2 1340, 1145 cm-1; Anal. Calcd. for C17H17ClN4O2S2: C,
49.93; H, 4.19; N, 13.70. Found: C, 49.98; H, 4.17; N, 13.74.
5-[2'-(4-Chlorophenyl)-3'-(4-chlorophenylsulfonyl)propyl]-
1,2,4-triazole-4-amino-3-thiol (13e). This compound was
obtained as white solid, mp 217-219°; ir: NH2 3265, SH 2580,
CN 1625, SO2 1325, 1141 cm-1; 1H nmr: ꢁ 2.90 (dd, 1H,
C1ꢀ-H, J=7.7, 16.1 Hz), 2.98 (dd, 1H, C1ꢀ-H, J=5.9, 16.4 Hz),
3.13 (dd, 1H, C3ꢀ-H, J=6.3, 14.2 Hz), 3.25 (dd, 1H, C3ꢀ-H,
J=7.3, 14.7 Hz), 4.17-4.22 (m, 1H, C2ꢀ-H), 5.52 (bs, 2H,
NH2), 7.11-7.82 (m, 8H, phenyl protons), 10.11 (s, 1H, SH);
13C nmr: ꢁ 38.5 (C-2ꢀ), 44.5 (C-1ꢀ), 55.2 (C-3ꢀ), 144.7 (C-3),
168.2 (C-5), 125.1, 126.9, 128.1, 129.4, 130.4, 131.8, 137.9,
140.1 (aromatic carbons).
5-[2'-(4-Chlorophenyl)-3'-(4-chlorophenylmethanesulfonyl)-
propyl]-1,3,4-oxadiazole-2-thiol (12e). This compound was
obtained as white solid, mp 189-191°; ir: SH 2560, CN 1624,
1
SO2 1326, 1128 cm-1; H nmr: ꢁ 2.89 (dd, 1H, C1ꢀ-H, J=7.5,
15.8 Hz), 2.95 (dd, 1H, C1ꢀ-H, J=6.3, 16.1 Hz), 3.06 (dd, 1H,
C3ꢀ-H, J=6.6, 14.0 Hz), 3.17 (dd, 1H, C3ꢀ-H, J=6.9, 14.8 Hz),
4.22-4.29 (m, 1H, C2ꢀ-H), 4.33 (s, 2H, Ar-CH2), 7.15-7.69 (m,
8H, phenyl protons), 10.31 (s, 1H, SH); 13C nmr: ꢁ 39.4 (C-2ꢀ),
45.2 (C-1ꢀ), 56.9 (C-3ꢀ), 59.1 (Ar-CH2), 160.1 (C-2), 169.7
(C-5), 125.7, 126.5, 127.1, 128.3, 129.6, 133.5, 138.7, 140.1
(aromatic carbons); Anal. Calcd. for C18H16Cl2N2O3S2: C, 48.76;
H, 3.64; N, 6.32. Found: C, 48.70; H, 3.66; N, 6.28.
5-[2'-Aryl-3'-(arylsulfonyl)propyl]-1,2,4-triazole-4-amino-
3-thiol (13) and 5-[2'-Aryl-3'-(arylmethanesulfonyl)propyl]-
1,2,4-triazole-4-amino-3-thiol (14): General procedure. To a
solution of potassium (3-aryl-4-arylsulfonyl-1-butanoyl)hydra-
zine-N'-carbodithioate (7)/ potassium (3-aryl-4-arylmethane-
sulfonyl-1-butanoyl)hydrazine-N'-carbodithioate (8) (1 mmole)
in water (6 mL), hydrazine hydrate (2 mmoles) was added and
refluxed for 7-9 hours. The contents of the flask were cooled,
diluted with water and acidified with acetic acid (2 mL). The
separated solid was collected by filtration, dried and
recrystallized from 2-propanol.
5-[2'-Phenyl-3'-(phenylmethanesulfonyl)propyl]-1,2,4-
triazole-4-amino-3-thiol (14a). This compound was obtained as
white solid, mp 189-191°; ir: NH2 3275, SH 2563, CN 1630,
1
SO2 1313, 1125 cm-1; H nmr: ꢁ 2.82 (dd, 1H, C1ꢀ-H, J=7.9,
15.8 Hz), 2.96 (dd, 1H, C1ꢀ-H, J=6.0, 16.2 Hz), 3.04 (dd, 1H,
C3ꢀ-H, J=6.5, 14.8 Hz), 3.17 (dd, 1H, C3ꢀ-H, J=6.8, 14.6 Hz),
4.18-4.22 (m, 1H, C2ꢀ-H), 4.26 (s, 2H, Ar-CH2), 5.82 (bs, 2H,
NH2), 7.12-7.50 (m, 10H, phenyl protons), 10.23 (s, 1H, SH);
13C nmr: ꢁ 39.8 (C-2ꢀ), 44.0 (C-1ꢀ), 56.7 (C-3ꢀ), 59.8 (Ar-CH2),
142.3 (C-3), 167.8 (C-5), 125.4, 125.9, 126.5, 127.8, 128.5,
133.4, 137.5, 138.6 (aromatic carbons); Anal. Calcd. for
C18H20N4O2S2: C, 55.65; H, 5.19; N, 14.42. Found: C, 55.60; H,
5.22; N, 14.36.
5-[2'-(4-Methylphenyl)-3'-(phenylmethanesulfonyl)propyl]-
1,2,4-triazole-4-amino-3-thiol (14b). This compound was
obtained as white solid, mp 211-213°; ir: NH2 3271, SH 2579,
CN 1626, SO2 1324, 1132 cm-1; 1H nmr: ꢁ 2.29 (s, 3H, Ar-CH3),
2.80 (dd, 1H, C1ꢀ-H, J=7.7, 16.1 Hz), 2.94 (dd, 1H, C1ꢀ-H, J=6.5,
16.2 Hz), 3.08 (dd, 1H, C3ꢀ-H, J=6.2, 14.5 Hz), 3.19 (dd, 1H,
C3ꢀ-H, J=7.1, 14.5 Hz), 4.20-4.25 (m, 1H, C2ꢀ-H), 4.31 (s, 2H,
Ar-CH2), 5.78 (bs, 2H, NH2), 7.10-7.61 (m, 9H, phenyl
protons), 10.28 (s, 1H, SH); 13C nmr: ꢁ 21.3 (Ar-CH3), 38.6 (C-
2ꢀ), 44.5 (C-1ꢀ), 55.4 (C-3ꢀ), 58.3 (Ar-CH2), 143.5 (C-3), 167.4
(C-5), 124.6, 125.5, 126.9, 127.6, 128.4, 131.7, 136.3, 139.9
(aromatic carbons).
5-[2'-Phenyl-3'-(phenylsulfonyl)propyl]-1,2,4-triazole-4-
amino-3-thiol (13a). This compound was obtained as white
solid, mp 201-203°; ir: NH2 3267, SH 2581, CN 1627, SO2
1
1326, 1121 cm-1; H nmr: ꢁ 2.85 (dd, 1H, C1ꢀ-H, J=8.0, 16.2
Hz), 2.97 (dd, 1H, C1ꢀ-H, J=6.1, 15.8 Hz), 3.10 (dd, 1H, C3ꢀ-H,
J=6.4, 15.0 Hz), 3.24 (dd, 1H, C3ꢀ-H, J=6.6, 14.8 Hz), 4.25-4.36
(m, 1H, C2ꢀ-H), 5.58 (bs, 2H, NH2), 7.05-7.49 (m, 10H, phenyl
protons), 10.12 (s, 1H, SH); 13C nmr: ꢁ 38.8 (C-2ꢀ), 44.5 (C-1ꢀ),
55.1 (C-3ꢀ), 144.5 (C-3), 169.8 (C-5), 125.8, 128.4, 129.0, 129.8,
132.3, 133.3, 133.9, 135.1 (aromatic carbons); Anal. Calcd. for
C17H18N4O2S2: C, 54.52; H, 4.84; N, 14.96. Found: C, 54.48; H,
4.87; N, 15.00.
5-[2'-(4-Chlorophenyl)-3'-(phenylmethanesulfonyl)propyl]-
1,2,4-triazole-4-amino-3-thiol (14c). This compound was
obtained as white solid, mp 204-206°; ir: NH2 3278, SH 2571,
CN 1628, SO2 1328, 1135 cm-1; Anal. Calcd. for
C18H19ClN4O2S2: C, 51.12; H, 4.53; N, 13.25. Found: C, 51.18;
H, 4.55; N, 13.31.
5-[2'-(4-Methylphenyl)-3'-(phenylsulfonyl)propyl]-1,2,4-
triazole-4-amino-3-thiol (13b). This compound was obtained as
white solid, mp 199-201°; ir: NH2 3258, SH 2573, CN 1628,
SO2 1328, 1134 cm-1; Anal. Calcd. for C18H20N4O2S2: C, 55.65;
H, 5.19; N, 14.42. Found: C, 55.71; H, 5.21; N, 14.47.
5-[2'-Phenyl-3'-(4-chlorophenylmethanesulfonyl)propyl]-
1,2,4-triazole-4-amino-3-thiol (14d). This compound was
obtained as white solid, mp 209-211°; ir: NH2 3280, SH 2568,
1
CN 1634, SO2 1325, 1134 cm-1; H nmr: ꢁ 2.84 (dd, 1H, C1ꢀ-H,
J=7.3, 15.3 Hz), 2.99 (dd, 1H, C1ꢀ-H, J=6.3, 16.0 Hz), 3.07 (dd,
1H, C3ꢀ-H, J=6.4, 14.5 Hz), 3.21 (dd, 1H, C3ꢀ-H, J=6.9, 14.6
Hz), 4.21-4.25 (m, 1H, C2ꢀ-H), 4.31 (s, 2H, Ar-CH2), 5.77 (bs,
2H, NH2), 7.15-7.82 (m, 9H, phenyl protons), 10.31 (s, 1H, SH);
13C nmr: ꢁ 39.8 (C-2ꢀ), 46.2 (C-1ꢀ), 55.8 (C-3ꢀ), 59.4 (Ar-CH2),
140.8 (C-3), 166.9 (C-5), 125.8, 126.8, 127.4, 128.3, 130.1,
133.7, 136.6, 139.4 (aromatic carbons).
5-[2'-(4-chlorophenyl)-3'-(4-chlorophenylmethanesulfonyl)-
propyl]-1,2,4-triazole-4-amino-3-thiol (14e). This compound
was obtained as white solid, mp 197-199°; ir: NH2 3273, SH
2577, CN 1627, SO2 1319, 1137 cm-1; Anal. Calcd. for
C18H18Cl2N4O2S2: C, 47.27; H, 3.97; N, 12.25. Found: C, 47.23;
H, 3.94; N, 12.29.
5-[2'-(4-Chlorophenyl)-3'-(phenylsulfonyl)propyl]-1,2,4-
triazole-4-amino-3-thiol (13c). This compound was obtained as
white solid, mp 207-209°; ir: NH2 3262, SH 2567, CN 1631,
1
SO2 1336, 1125 cm-1; H nmr: ꢁ 2.89 (dd, 1H, C1ꢀ-H, J=8.4,
16.0 Hz), 2.97 (dd, 1H, C1ꢀ-H, J=6.3, 16.4 Hz), 3.07 (dd, 1H,
C3ꢀ-H, J=5.8, 14.4 Hz), 3.18 (dd, 1H, C3ꢀ-H, J=6.5, 14.5 Hz),
4.24-4.28 (m, 1H, C2ꢀ-H), 5.54 (bs, 2H, NH2), 7.08-7.85 (m, 9H,
phenyl protons), 10.08 (s, 1H, SH); 13C nmr: ꢁ 38.7 (C-2ꢀ), 43.4
(C-1ꢀ), 55.6 (C-3ꢀ), 144.8 (C-3), 167.5 (C-5), 125.4, 126.1,
127.3, 128.7, 129.8, 131.7, 134.2, 138.1 (aromatic carbons).
5-[2'-Phenyl-3'-(4-chlorophenylsulfonyl)propyl]-1,2,4-
triazole-4-amino-3-thiol (13d). This compound was obtained as

Nov-Dec 2008
Michael Adducts of Vinyl Sulfones – Source for Thiadiazoles, Oxadiazoles and Triazoles
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[7] Shadomy, S.; White, S. C.; Yu, H. P. J. Infect. Dis. 1985,
152, 1249.
[8] Demir-Erol, D.; ¸ Calıs, U.; Demirdamar, R.; Yulug, N.;
Ertan, M. J. Pharm. Sci. 1995, 84, 462.
Acknowledgement. The authors are thankful to Department
of Science and Technology (DST), New Delhi for financial
assistance under major research project.
[9] Kariyone, K.; Harada, H.; Kuritha, M.; Takaano, T. Antibiot
J. 1970, 23, 131.
REFERENCES
[10] Naito, K.; Watanabe, Y.; Egusa, S. Jpn. J. Appl. Phys. Part I
1999, 38, 2792.
[11] Holla, B. S.; Gonsalves, R.; Shenoy, S. Eur. J. Med. Chem.
2000, 35, 267.
[12] Tinperciuc, B.; Parvu, A.; Palage, M.; Oniga, O.; Ghiran, D.
Farmacia (Bucharest) 1999, 47, 77.
[13] Harayama, T.; Tezuka, Y.; Taga, T.; Yoneda, F.
Tetrahedron Lett. 1984, 25, 4015.
[14] Padmavathi, V.; Venkata Subbaiah, D. R. C.; Balaiah, A.;
Chandra Obula Reddy, B.; Padmaja, A. Indian J. Chem. 2005, 44B, 2569.
[15] Bhaskar Reddy, D.; Ramana Reddy, P. V.; Padmavathi, V.;
Ramana Reddy, M. V. Sulfur Lett. 1991, 13, 83.
[1] Eweiss, N. F.; Bahajaj, A. A.; Elsherbini, E. A. J.
Heterocyclic Chem. 1986, 23, 1451.
[2] EL-Dawy, M. A.; Omar, A. M. M.; Ismail, A. M.; B. Hazzaa,
A. A. J. Pharm. Sci. 1983, 43, 45.
[3] Lutwick, L. L.; Rytel, W. M. J. Am. Med. Assoc. 1979, 241,
271.
[4] Fromtling, R. A. Clin. Microbiol. Rev. 1988, 1, 187.
[5] Godefroi, E. F.; Heeres, J.; Van Cutsem, J. J. Med. Chem.
1969, 12, 784.
[6] Odds, F. C.; Abbott, A. B. J. Antimicrob. Chemother 1984,
14, 105.