Pyrrolo[2,1-b]thiazol-3(2H)-ones as precursors of N-alkyl-2-(1H-pyrrol-2- ylthio)acetamides and N-alkyl-2-(1H-pyrrol-2-ylthio)propanamides

Article abstract of DOI:10.1055/s-2004-831178

6-Aryl-2,3-dihydro-3-oxopyrrolo[2,1-b]thiazole-7-carboxylic acids ethyl esters were prepared by refluxing 2-[3-(2-aryl-2-oxoethyl)-4-oxo-2- thiazolidinylidene]acetic acid ethyl esters in POCl₃. An amination of the obtained pyrrolo[2,1-b]thiazol

Full text of DOI:10.1055/s-2004-831178

PAPER
2317
Pyrrolo[2,1-b]thiazol-3(2H)-ones as Precursors of N-Alkyl-2-(1H-pyrrol-
2-ylthio)acetamides and N-Alkyl-2-(1H-pyrrol-2-ylthio)propanamides
N
-Alkyl-2-(
1
H-py
n
r
rol-2-ylthio)
t
acetam
o
ides and-pr
o
n
panamide
s
V. Tverdokhlebov,*a Alexander P. Andrushko,a Elizaveta V. Resnyanska,a Andrey A. Tolmachevb
a
Enamine Ltd., Alexandra Matrosova Str. 23, 01103, Kiev, Ukraine
b
Kiev National Taras Shevchenko University, Volodimirska str. 62, 01033, Kiev, Ukraine
E-mail: atver@univ.kiev.ua
Received 12 May 2004
unstable materials and can not be isolated.4c,d Neverthe-
less this is a relatively general synthetic method, but it
also has some shortcomings, especially the thiocyanation
in uncertain position of asymmetrically substituted pyr-
Abstract: 6-Aryl-2,3-dihydro-3-oxopyrrolo[2,1-b]thiazole-7-car-
boxylic acids ethyl esters were prepared by refluxing 2-[3-(2-aryl-
2-oxoethyl)-4-oxo-2-thiazolidinylidene]acetic acid ethyl esters in
POCl3. An amination of the obtained pyrrolo[2,1-b]thiazole deriva-
tives with primary aliphatic amines was found to yield N-alkyl-2- roles. Moreover, protection of the pyrrole nitrogen atom
was needed to prepare N-unsubstituted derivatives,4f thus
[(4-aryl-3-ethoxycarbonyl-2-pyrrolyl)thio]acetamides and -propan-
amides.
making the sequence at least two steps longer. Finally,
thiocyanopyrroles were found to irritate skin and eyes.4d
Key words: aminations, cyclizations, pyrroles, pyrrolo[2,1-b]thia-
zoles, ring opening
Other known approaches to 2-(alkylthio)pyrroles are
based on either cycloaddition reactions of nitrile ylides5
and certain heterocyclic dienes6 or condensation reactions
In spite of the fact that the structure of 2-(2-pyrrolyl-
of ketene S,S- and S,N-acetals.7 However these methods
thio)acetic acid is simple, only a limited number of its de-
are limited to the synthesis of methyl- and ethylthiopyr-
rivatives are reported in the literature. Similar to other
roles and are inapplicable to 2-(2-pyrrolylthio)acetic acid
heterocycles, an alkylation of 2-pyrrolethiols with chloro-
derivatives preparation. Also an attempt of direct intro-
acetic acid derivatives seems to be the easiest approach to
duction of mercaptoacetic acid moiety into pyrrole nucle-
these compounds. However, only four relatively stable 2-
us using methyl mercaptoacetate/iodine system was
pyrrolethiols are known to date1,2 (Figure 1). Thus, com-
examined,8 but the result was unsatisfactory. Hence elab-
pounds 1a–c were prepared from malonodinitrile, cy-
oration of novel approaches to 2-(2-pyrrolylthio)acetic
acid esters and (or) amides not derived from the structures
1 and 2 is needed.
anoacetamide or ethyl cyanoacetate and sulfur via
Dimroth rearrangement of intermediate diami-
nothiophenes.1a–1c Their yields were low (30–40%), but it
N-Acylpyrroles are known to act as mild acylating agents
was compensated with a cheapness of the starting materi-
towards some amines.9 Pyrrolo[2,1-b]thiazol-3(2H)-ones
als. The derivative 1a was also obtained from tetracyano-
also consist of N-acylpyrrole moiety. Therefore it seems
ethane.1d Furthermore, compound 2 was prepared from
cyanothioacetamide and benzoin.2 So most of the known
2-(2-pyrrolylthio)acetic acid derivatives were drawn from
the structures 1 and 2.1d,2,3
reasonable to assume their amination would give 2-(2-
pyrrolylthio)acetamides. Recently we have reported10
a
convenient three-step synthesis of desired pyrrolo[2,1-
b]thiazol-3-one derivatives 4 starting from ethyl cyanoac-
etate (Scheme 1). However, amination of the compounds
4 yielded complex mixtures, probably, because of com-
petitive substitution of the dimethylamino group. Con-
tinuing our investigations in this field we have now found
a transformation of the derivatives 3 into another kind of
pyrrolo[2,1-b]thiazol-3-ones. Their amination has been
examined and the results are reported herein.
Figure 1 2-Pyrrolethiols 1; X = a: CN, b: CONH2, c: CO2Et and 2
Thus, upon refluxing in POCl3, compounds 3 were found
to give pyrrolo[2,1-b]thiazole derivatives 6 in good yields
(Scheme 2). Formally this reaction is alike Chichibabin
pyrrolothiazole synthesis.11 However, in contrast with the
basic conditions used in the typical procedure11 the acidic
ones were employed in the present case. Unlike deriva-
tives 4, compounds 6 have no a dimethylaminometh-
ylidene moiety and, therefore, seem to be better objects
for amination. Indeed, their treatment with primary ali-
phatic amines resulted in the target 2-(2-pyrrolylthio)acet-
amides 8 without remarkable side processes. The method
A multi-step sequence is required to bring in mercap-
toacetic acid moiety into other pyrroles. It includes initial
thiocyanation of pyrrole and further hydrolytic or reduc-
tive cleavage of the introduced thiocyano group into thiol
one, which is subjected to alkylation immediately.4 The
latter is important since the intermediate pyrrolethiols are
SYNTHESIS 2004, No. 14, pp 2317–2322
x
x.
x
x
.
2
0
0
4
Advanced online publication: 17.08.2004
DOI: 10.1055/s-2004-831178; Art ID: Z09004SS
© Georg Thieme Verlag Stuttgart · New York

2318
A. V. Tverdokhlebov et al.
PAPER
Table 1 Compounds 3, 5, 6–9 Synthesized
No
3a
3b
3c
5a
5b
6a
6b
6c
7a
7b
8a
8b
8c
8d
8e
8f
R
Ar
Alk
Yield, %
–
H
4-BrC6H4
4-ClC6H4
C6H5
–
H
–
–
H
–
–
CH3
CH3
H
4-BrC6H4
4-ClC6H4
4-BrC6H4
4-ClC6H4
C6H5
–
91
94
84
86
87
78
96
84
78
73
75
82
61
84
76
69
79
77
63
71
84
74
–
–
H
–
Scheme 1 Synthesis of 4 according to the Ref.10
H
–
was successfully extended to the preparation of 2-(2-pyr-
rolylthio)propanamides 9 starting from the methyl substi-
CH3
CH3
H
4-BrC6H4
4-ClC6H4
4-BrC6H4
4-BrC6H4
4-BrC6H4
4-ClC6H4
4-ClC6H4
4-ClC6H4
C6H5
–
–
tuted derivatives
5
through pyrrolothiazoles 7.
Compounds 5 were obtained easily from ethyl cyanoace-
tate following an analogy with the Scheme 1, but using 2-
mercaptopropionic acid instead of mercaptoacetic acid.
The overall yields of the amides 8,9 from the derivatives
3,5 were 50–75%. Unfortunately, pyrrolothiazoles 6,7 ap-
peared to be weak acylating agents and failed to react with
anilines. Hence the scope of the method is limited only to
the synthesis of N-alkyl substituted amides 8,9. The yields
of compounds 3, 5, 6–9 prepared are listed in Table 1.
C6H5CH2
H
3,4-(MeO)2C6H3CH2
4-MeOC6H4CH2CH2
C6H5CH2
H
H
H
3,4-(MeO)2C6H3CH2
4-MeOC6H4CH2CH2
C6H5CH2
H
8g
8h
8i
H
H
C6H5
3,4-(MeO)2C6H3CH2
4-MeOC6H4CH2CH2
C6H5CH2
H
C6H5
9a
9b
9c
9d
9e
9f
CH3
CH3
CH3
CH3
CH3
CH3
4-BrC6H4
4-BrC6H4
4-BrC6H4
4-ClC6H4
4-ClC6H4
4-ClC6H4
3,4-(MeO)2C6H3CH2
4-MeOC6H4CH2CH2
C6H5CH2
Scheme 2 For R, Ar and Alk, see Table 1
The structures of the obtained compounds 6–9 were con-
firmed by 1H, 13C and 2D NMR (NOESY, HSQC, HMBC
experiments) data. Particularly, the long-range C-H corre-
lation (HMBC) experiment gave most informative data.
Thus for derivatives 6,7 it revealed five correlations of the
singlet of 5-H (7.2–7.5 ppm) with the following carbons
signals: 3-CO, 6-C, 7-C, 7a-C and 1¢-C of the Ar substit-
uent. Simultaneously for compounds 8,9 the same pro-
ton’s signal appeared at 6.7–6.9 ppm and exhibited only
four correlations with 2-C, 3-C and 4-C of pyrrole nucleus
and with 1¢-C of the Ar group. So the correlation between
5-H and the amide moiety carbon vanished after transfor-
mation of derivatives 6,7 into 8,9, thus indicating clearly
the thiazole ring cleavage at CO–N bond. Also it is note-
worthy that the signal of the above mentioned proton is
shifted upfield of ca. 0.5 ppm in compounds 8,9 compared
to their precursors 6,7. This is explained by deshielding of
the proton by the neighboring magnetically anisotropic
carbonyl in the derivatives 6,7, which is absent for amides
8,9. Therefore, this shift also points indirectly at the thia-
3,4-(MeO)2C6H3CH2
4-MeOC6H4CH2CH2
zole ring cleavage. Furthermore, for most of pyrroles 8,9
the signal of 5-H was observed as doublet (J = ca. 2.0–2.5
Hz) due to a coupling with NH (11.8–12.0 ppm), whereas
in the spectra of pyrrolothiazoles 6,7 it looked as a singlet.
Other signals and their mutual correlations were also in
good agreement with the structures 6–9.
In summary, pyrrolo[2,1-b]thiazol-3-ones 6,7 have been
shown to be suitable precursors of 2-(2-pyrrolylthio)acet-
amides 8 and -propanamides 9 unavailable via known pro-
cedures.1–4 To the best of our knowledge it is the first
example of the nucleophile-induced thiazole ring cleav-
age in the pyrrolo[2,1-b]thiazole system. Previously only
desulfurization12 and base-induced cleavage13 were re-
ported. Moreover, compounds 8,9 have been prepared, in
fact, starting from ethyl cyanoacetate in four steps. Other
reagents used are also readily available and experimental
Synthesis 2004, No. 14, 2317–2322 © Thieme Stuttgart · New York

PAPER
N-Alkyl-2-(1H-pyrrol-2-ylthio)acetamides and -propanamides
2319
1H NMR: d = 1.28 (t, J = 7.2 Hz, 3 H, CH3), 4.18 (q, J = 7.2 Hz, 2
H, OCH2), 4.34 (s, 2 H, 2-CH2), 7.27 (s, 1 H, 5-H), 7.31 (d, J = 8.4
Hz, 2 H, Ar), 7.45 (d, J = 8.4 Hz, 2 H, Ar).
13C NMR: d = 14.7 (CH3), 38.0 (2-C), 60.5 (OCH2), 108.4 (7-C),
113.4 (5-C), 128.3 (3,5-CAr), 129.6 (4-CAr), 131.3 (2,6-CAr), 132.2
(1-CAr), 132.8 (6-C), 145.3 (7a-C), 163.0 (COO), 168.6 (3-CO).
technique employed is simple. It provides an easy access
to the amides 8,9 and makes an advantage of the method
in comparison with the thiocyanation based approaches.4
All melting points were determined in open capillary tubes in a
Thiele apparatus and are uncorrected. 1H NMR spectra were record-
ed on a Mercury 400 (400 MHz) spectrometer in DMSO-d6 solu-
tions. Chemical shifts (d) are given in ppm downfield from internal
Me4Si. J values are in Hz. 13C and 2D NMR experiments were per-
formed on a Bruker Avance 500 (at 500 MHz for 1H and 125 MHz
for 13C) spectrometer. The purity of all compounds prepared was
checked by 1H NMR.
The starting compounds 3a–c were prepared as reported.10 Methyl
substituted derivatives 5a,b were obtained from 2-(4-oxo-5-methyl-
2-thiazolidinylidene)acetic acid ethyl ester14 following the same
procedure.10
Anal. Calcd for C15H12ClNO3S: C, 55.99; H, 3.76; Cl, 11.02; N,
4.35; S, 9.96. Found: C, 56.21; H, 3.82; Cl, 10.75; N, 4.17; S, 9.97.
2,3-Dihydro-3-oxo-6-phenylpyrrolo[2,1-b]thiazole-7-carboxyl-
ic Acid Ethyl Ester (6c)
Mp 69 °C (i-PrOH).
1H NMR: d = 1.27 (t, J = 7.0 Hz, 3 H, CH3), 4.17 (q, J = 7.0 Hz, 2
H, OCH2), 4.35 (s, 2 H, 2-CH2), 7.22 (s, 1 H, 5-H), 7.31 (m, 3 H,
Ar), 7.44 (dd, J3 = 6.8 Hz, J4 = 0.8 Hz, 2 H, Ar).
13C NMR: d = 14.9 (CH3), 38.0 (2-C), 60.8 (OCH2), 110.2 (7-C),
116.3 (5-C), 126.0 (4-CAr), 128.0 (3,5-CAr), 129.5 (2,6-CAr), 131.7
(6-C), 135.3 (1-CAr), 143.9 (7a-C), 163.2 (COO), 166.9 (3-CO).
2-{3-[2-(4-Bromophenyl)-2-oxoethyl]-5-methyl-4-oxo-2-thiazo-
lidinylidene}acetic Acid Ethyl Ester (5a)
Mp 126 °C (EtOH).
1H NMR: d = 1.15 (t, J = 7.0 Hz, 3 H, CH3), 1.51 (d, J = 7.2 Hz, 3
H, CH3), 4.05 (q, J = 7.0 Hz, 2 H, OCH2), 4.22 (q, J = 7.2 Hz, 1 H,
SCH), 5.35 (s, 2 H, NCH2), 5.64 (s, 1 H, =CH), 7.80 (d, J = 8.4 Hz,
2 H, Ar), 7.98 (d, J = 8.4 Hz, 2 H, Ar).
Anal. Calcd for C15H13NO3S: C, 62.70; H, 4.56; N, 4.87; S, 11.16.
Found: C, 62.53; H, 4.77; N, 4.90; S, 10.93.
6-(4-Bromophenyl)-2,3-dihydro-2-methyl-3-oxopyrrolo[2,1-
b]thiazole-7-carboxylic Acid Ethyl Ester (7a)
Mp 71 °C (i-PrOH).
1H NMR: d = 1.19 (t, J = 7.2 Hz, 3 H, CH3), 1.63 (d, J = 7.2 Hz, 3
H, 2-CH3), 4.14 (q, J = 7.2 Hz, 2 H, OCH2), 4.73 (q, J = 7.2 Hz, 1
H, 2-H), 7.41 (d, J = 8.0 Hz, 2 H, Ar), 7.49 (m, 3 H, 5-H, Ar).
Anal. Calcd for C16H16BrNO4S: C, 48.25; H, 4.05; Br, 20.06; N,
3.52; S, 8.05. Found: C, 48.16; H, 4.15; Br, 19.88; N, 3.63; S, 8.15.
2-{3-[2-(4-Chlorophenyl)-2-oxoethyl]-5-methyl-4-oxo-2-thiazo-
lidinylidene}acetic Acid Ethyl Ester (5b)
Mp 92 °C (EtOH).
1H NMR: d = 1.23 (t, J = 7.0 Hz, 3 H, CH3), 1.61 (d, J = 6.8 Hz, 3
H, CH3), 4.07 (m, 3 H, OCH2, SCH), 5.24 (s, 2 H, NCH2), 5.44 (s,
1 H, =CH), 7.52 (d, J = 8.8 Hz, 2 H, Ar), 8.06 (d, J = 8.8 Hz, 2 H,
Ar).
13C NMR: d = 14.5 (CH3), 17.8 (2-CH3), 47.5 (2-C), 60.2 (OCH2),
108.2 (7-C), 113.4 (5-C), 127.7 (4-CAr), 128.1 (3,5-CAr), 131.1 (2,6-
CAr), 131.9 (1-CAr), 132.7 (6-C), 143.1 (7a-C), 162.7 (COO), 171.4
(3-CO).
Anal. Calcd for C16H14BrNO3S: C, 50.54; H, 3.71; Br, 21.01; N,
3.68; S, 8.43. Found: C, 50.50; H, 3.81; Br, 21.11; N, 3.42; S, 8.21.
Anal. Calcd for C16H16ClNO4S: C, 54.31; H, 4.56; Cl, 10.02; N,
3.96; S, 9.06. Found: C, 54.16; H, 4.46; Cl, 10.06; N, 4.12; S, 9.04.
6-(4-Chlorophenyl)-2,3-dihydro-2-methyl-3-oxopyrrolo[2,1-
b]thiazole-7-carboxylic Acid Ethyl Ester (7b)
Mp 82 °C (i-PrOH).
Pyrrolo[2,1-b]thiazoles 6a–c, 7a,b; General Procedure
A solution of the thiazole derivative 3,5 (5 mmol) in POCl3 (5 mL)
was refluxed for 3 h. After cooling, it was poured onto crushed ice
and the solid formed was filtered, washed sequentially with sat. aq
NaHCO3 and H2O, and air dried. Obtained materials were of satis-
factory purity to be used in the next step. Analytical samples were
additionally purified by recrystallization from an appropriate sol-
vent.
1H NMR: d = 1.28 (t, J = 7.0 Hz, 3 H, CH3), 1.70 (d, J = 7.2 Hz, 3
H, 2-CH3), 4.18 (q, J = 7.0 Hz, 2 H, OCH2), 4.60 (q, J = 7.2 Hz, 1
H, 2-H), 7.24 (s, 1 H, 5-H), 7.30 (d, J = 8.0 Hz, 2 H, Ar), 7.44 (d,
J = 8.0 Hz, 2 H, Ar).
13C NMR: d = 15.3 (CH3), 17.0 (2-CH3), 47.0 (2-C), 59.2 (OCH2),
110.9 (7-C), 116.2 (5-C), 129.6 (2,6-CAr), 129.7 (3,5-CAr), 131.8 (4-
CAr), 132.2 (6-C), 134.5 (1-CAr), 144.1 (7a-C), 160.6 (COO), 171.7
(3-CO).
6-(4-Bromophenyl)-2,3-dihydro-3-oxopyrrolo[2,1-b]thiazole-7-
carboxylic Acid Ethyl Ester (6a)
Mp 126 °C (EtOH).
Anal. Calcd for C16H14ClNO3S: C, 57.23; H, 4.20; Cl, 10.56; N,
4.17; S, 9.55. Found: C, 57.46; H, 4.19; Cl, 10.59; N, 4.25; S, 9.66.
1H NMR: d = 1.20 (t, J = 7.2 Hz, 3 H, CH3), 4.15 (q, J = 7.2 Hz, 2
H, OCH2), 4.41 (s, 2 H, 2-CH2), 7.43 (d, J = 8.4 Hz, 2 H, Ar), 7.48
(s, 1 H, 5-H), 7.54 (d, J = 8.4 Hz, 2 H, Ar).
13C NMR: d = 16.8 (CH3), 35.4 (2-C), 62.8 (OCH2), 109.4 (7-C),
112.9 (5-C), 126.8 (3,5-CAr), 128.1 (4-CAr), 129.2 (2,6-CAr), 129.8
(1-CAr), 133.0 (6-C), 146.4 (7a-C), 163.5 (COO), 169.8 (3-CO).
2-(2-Pyrrolylthio)acetamides 8a–i and 2-(2-Pyrrolylthio)pro-
panamides 9a–f; General Procedure
A solution of pyrrolo[2,1-b]thiazole 6,7 (3 mmol) and the corre-
sponding amine (4.5 mmol) in EtOH (5 mL) was refluxed for 1 h.
When the reaction was carried out with benzylamine, after cooling
the precipitate formed was filtered, washed with H2O and recrystal-
lized from appropriate solvent to give amides 8a,d,g and 9a,d. For
other amines the mixture was poured into water, the solid formed
was filtered and recrystallized from appropriate solvent to yield de-
rivatives 8b,c,e,f,h,i and 9b,c,e,f.
Anal. Calcd for C15H12BrNO3S: C, 49.19; H, 3.30; Br, 21.82; N,
3.82; S, 8.76. Found: C, 49.36; H, 3.23; Br, 21.95; N, 3.93; S, 8.83.
6-(4-Chlorophenyl)-2,3-dihydro-3-oxopyrrolo[2,1-b]thiazole-7-
carboxylic Acid Ethyl Ester (6b)
Mp 145 °C (EtOH).
4-(4-Bromophenyl)-2-{[2-oxo-2-(benzyamino)ethyl]thio}-1H-
pyrrole-3-carboxylic Acid Ethyl Ester (8a)
Mp 107 °C (EtOH).
Synthesis 2004, No. 14, 2317–2322 © Thieme Stuttgart · New York

2320
A. V. Tverdokhlebov et al.
PAPER
1H NMR: d = 1.18 (t, J = 6.0 Hz, 3 H, CH3), 3.63 (s, 2 H, SCH2),
4.11 (q, J = 6.0 Hz, 2 H, OCH2), 4.35 (s, 2 H, NCH2), 6.87 (s, 1 H,
5-H), 7.25 (m, 7 H, Ar, Alk), 7.40 (d, J = 8.4 Hz, 2 H, Ar), 8.66 (br
s, 1 H, CONH), 11.93 (br s, 1 H, NH).
4-(4-Chlorophenyl)-2-[(2-{[(3,4-dimethoxyphenyl)methyl]ami-
no}-2-oxoethyl)thio]-1H-pyrrole-3-carboxylic Acid Ethyl Ester
(8e)
Mp 150 °C (i-PrOH).
13C NMR: d = 12.7 (CH3), 38.0 (SCH2), 45.5 (NCH2), 57.4 (OCH2),
115.0 (3-C), 119.2 (5-C), 120.0 (4-CAr), 126.3 (3,5-CAlk), 127.1 (4-
C), 127.5 (2-C), 127.8 (4-CAlk), 128.8 (2,6-CAlk), 129.2 (3,5-CAr),
133.6 (2,6-CAr), 135.1 (1-CAr), 139.3 (1-CAlk), 164.1 (COO), 169.9
(CONH).
1H NMR: d = 1.17 (t, J = 7.0 Hz, 3 H, CH3), 3.59 (s, 2 H, SCH2),
3.74 (s, 6 H, OCH3), 4.09 (q, J = 7.0 Hz, 2 H, OCH2), 4.26 (d,
J = 5.6 Hz, 2 H, NCH2), 6.73 (m, 2 H, Alk), 6.81 (m, 2 H, 5-H, Alk),
7.23 (d, J = 8.8 Hz, 2 H, Ar), 7.27 (d, J = 8.8 Hz, 2 H, Ar), 8.67 (t,
J = 5.6 Hz, 1 H, CONH), 11.98 (s, 1 H, NH).
Anal. Calcd for C22H21BrN2O3S: C, 55.82; H, 4.47; Br, 16.88; N,
5.92; S, 6.77. Found: C, 55.62; H, 4.60; Br, 16.84; N, 6.05; S, 6.66.
13C NMR: d = 16.1 (CH3), 37.5 (SCH2), 43.1 (NCH2), 53.9 (OCH3),
55.9 (OCH3), 57.9 (OCH2), 112.0 (2-CAlk), 112.1 (5-CAlk), 113.8 (3-
C), 117.9 (6-CAlk), 119.1 (5-C), 125.0 (4-C), 125.5 (4-CAr), 128.0
(2-C), 129.8 (2,6-CAr), 131.6 (3,5-CAr), 131.8 (1-CAlk), 135.0 (1-
CAr), 147.1 (4-CAlk), 147.5 (3-CAlk), 162.8 (COO), 169.0 (CONH).
4-(4-Bromophenyl)-2-[(2-{[(3,4-dimethoxyphenyl)methyl]ami-
no}-2-oxoethyl)thio]-1H-pyrrole-3-carboxylic Acid Ethyl Ester
(8b)
Anal. Calcd for C24H25ClN2O5S: C, 58.95; H, 5.15; Cl, 7.25; N,
5.73; S, 6.56. Found: C, 58.73; H, 4.98; Cl, 7.35; N, 5.88; S, 6.53.
Mp 162 °C (i-PrOH).
1H NMR: d = 1.18 (t, J = 7.2 Hz, 3H, CH3), 3.61 (s, 2 H, SCH2),
3.74 (s, 6 H, OCH3), 4.10 (q, J = 7.2 Hz, 2 H, OCH2), 4.26 (d,
J = 5.6 Hz, 2 H, NCH2), 6.72 (d, J = 8.4 Hz, 1 H, Alk), 6.77 (d,
J = 8.4 Hz, 1 H, Alk), 6.81 (s, 1 H, Alk), 6.86 (d, J = 2.4 Hz, 1 H,
5-H), 7.23 (d, J = 8.0 Hz, 2 H, Ar), 7.40 (d, J = 8.0 Hz, 2 H, Ar),
8.64 (t, J = 5.6 Hz, 1 H, CONH), 11.96 (br s, 1 H, NH).
13C NMR: d = 14.3 (CH3), 37.9 (SCH2), 42.7 (NCH2), 55.8 (OCH3),
55.9 (OCH3), 59.7 (OCH2), 111.7 (2-CAlk), 112.1 (5-CAlk), 113.8 (3-
C), 119.5 (4-CAr), 119.7 (6-CAlk), 120.2 (5-C), 125.2 (4-C), 128.5
(2-C), 130.8 (3,5-CAr), 131.0 (2,6-CAr), 131.6 (1-CAlk), 134.7 (1-
CAr), 148.2 (4-CAlk), 149.0 (3-CAlk), 164.4 (COO), 168.9 (CONH).
4-(4-Chlorophenyl)-2-[(2-{[2-(4-methoxyphenyl)ethyl]amino}-
2-oxoethyl)thio]-1H-pyrrole-3-carboxylic Acid Ethyl Ester (8f)
Mp 104 °C (i-PrOH–H2O).
1H NMR: d = 1.18 (t, J = 7.0 Hz, 3 H, CH3), 2.69 (t, J = 7.2 Hz, 2
H, CH2), 3.32 (m, 2 H, NCH2), 3.51 (s, 2 H, SCH2), 3.72 (s, 3 H,
OCH3), 4.11 (q, J = 7.0 Hz, 2 H, OCH2), 6.75 (d, J = 8.4 Hz, 2 H,
Alk), 6.82 (d, J = 2.8 Hz, 1 H, 5-H), 7.07 (d, J = 8.4 Hz, 2 H, Alk),
7.23 (d, J = 8.8 Hz, 2 H, Ar), 7.28 (d, J = 8.8 Hz, 2 H, Ar), 8.27 (t,
J = 6.4 Hz, 1 H, CONH), 11.98 (br s, 1 H, NH).
13C NMR: d = 15.6 (CH3), 38.3 (SCH2), 41.0 (CH2), 48.9 (NCH2),
54.2 (OCH3), 62.1 (OCH2), 115.5 (3,5-CAlk), 118.7 (3-C), 121.0 (5-
C), 125.0 (4-C), 127.2 (4-CAr), 128.0 (2,6-CAlk), 129.2 (2-C), 130.0
(2,6-CAr), 131.0 (3,5-CAr), 132.0 (1-CAlk), 135.0 (1-CAr), 156.1 (4-
CAlk), 166.7 (COO), 170.2 (CONH).
Anal. Calcd for C24H25BrN2O5S: C, 54.04; H, 4.72; Br, 14.98; N,
5.25; S, 6.01. Found: C, 54.23; H, 4.81; Br, 14.75; N, 5.22; S, 6.14.
4-(4-Bromophenyl)-2-[(2-{[2-(4-methoxyphenyl)ethyl]amino}-
2-oxoethyl)thio]-1H-pyrrole-3-carboxylic Acid Ethyl Ester (8c)
Viscous oil (i-PrOH–H2O).
Anal. Calcd for C24H25ClN2O4S: C, 60.95; H, 5.33; Cl, 7.50; N,
5.92; S, 6.78. Found: C, 60.96; H, 5.42; Cl, 7.59; N, 6.05; S, 6.72.
1H NMR: d = 1.19 (t, J = 8.4 Hz, 3 H, CH3), 2.68 (t, J = 6.4 Hz, 2
H, CH2), 3.30 (m, 2 H, NCH2), 3.53 (s, 2 H, SCH2), 3.72 (s, 3 H,
OCH3), 4.11 (q, J = 8.4 Hz, 2 H, OCH2), 6.76 (d, J = 10.4 Hz, 2 H,
Alk), 6.86 (d, J = 2.8 Hz, 1 H, 5-H), 7.07 (d, J = 10.4 Hz, 2 H, Alk),
7.23 (d, J = 8.0 Hz, 2 H, Ar), 7.39 (d, J = 8.0 Hz, 2 H, Ar), 8.26 (t,
J = 9.2 Hz, 1 H, CONH), 11.96 (br s, 1 H, NH).
13C NMR: d = 15.2 (CH3), 38.5 (SCH2), 42.3 (CH2), 49.2 (NCH2),
58.1 (OCH3), 59.0 (OCH2), 113.5 (3-C), 114.3 (3,5-CAlk), 118.1 (4-
CAr), 121.0 (5-C), 124.1 (4-C), 129.2 (2,6-CAlk), 129.3 (2-C), 130.4
(3,5-CAr), 130.7 (1-CAlk), 131.0 (2,6-CAr), 136.6 (1-CAr), 158.0 (4-
CAlk), 166.0 (COO), 168.0 (CONH).
2-{[2-Oxo-2-(benzylamino)ethyl]thio}-4-phenyl-1H-pyrrole-3-
carboxylic Acid Ethyl Ester (8g)
Mp 149 °C (EtOH).
1H NMR: d = 1.14 (t, J = 7.2 Hz, 3 H, CH3), 3.64 (s, 2 H, SCH2),
4.09 (q, J = 7.2 Hz, 2 H, OCH2), 4.33 (d, J = 5.6 Hz, 2 H, NCH2),
6.87 (d, J = 2.4 Hz, 1 H, 5-H), 7.21 (m, 4 H, Ar, Alk), 7.28 (m, 6 H,
Ar, Alk), 8.72 (t, J = 5.6 Hz, 1 H, CONH), 11.89 (br s, 1 H, NH).
13C NMR: d = 14.5 (CH3), 38.4 (SCH2), 43.0 (NCH2), 59.9 (OCH2),
114.7 (3-C), 120.1 (5-C), 126.5 (4-CAr), 126.7 (2-C), 127.4 (4-CAlk),
127.7 (2,6-CAlk), 128.0 (4-C), 128.2 (3,5-CAr), 128.9 (3,5-CAlk),
129.0 (2,6-CAr), 135.6 (1-CAr), 139.4 (1-CAlk), 164.8 (COO), 169.2
(CONH).
Anal. Calcd for C24H25BrN2O4S: C, 55.71; H, 4.87; Br, 15.44; N,
5.41; S, 6.20. Found: C, 55.81; H, 4.73; Br, 15.60; N, 5.26; S, 6.28.
Anal. Calcd for C22H22N2O3S: C, 66.98; H, 5.62; N, 7.10; S, 8.13.
Found: C, 66.77; H, 5.69; N, 6.97; S, 8.17.
4-(4-Chlorophenyl)-2-{[2-oxo-2-(benzylamino)ethyl]thio}-1H-
pyrrole-3-carboxylic Acid Ethyl Ester (8d)
Mp 123 °C (EtOH).
1H NMR: d = 1.17 (t, J = 7.2 Hz, 3 H, CH3), 3.60 (s, 2 H, SCH2),
4.10 (q, J = 7.2 Hz, 2 H, OCH2), 4.35 (d, J = 5.6 Hz, 2 H, NCH2),
6.81 (d, J = 2.4 Hz, 1 H, 5-H), 7.23 (m, 9 H, Ar, Alk), 8.70 (t, J = 5.6
Hz, 1 H, CONH), 11.96 (br s, 1 H, NH).
13C NMR: d = 12.1 (CH3), 38.0 (SCH2), 43.7 (NCH2), 59.1 (OCH2),
117.7 (3-C), 119.7 (5-C), 127.0 (2-C), 127.1 (4-CAlk), 127.7 (4-CAr),
128.0 (4-C), 129.0 (3,5-CAlk), 129.4 (2,6-CAlk), 129.5 (3,5-CAr),
131.6 (2,6-CAr), 134.5 (1-CAr), 137.1 (1-CAlk), 165.5 (COO), 167.4
(CONH).
2-[(2-{[(3,4-Dimethoxyphenyl)methyl]amino}-2-oxoethyl)thio]-
4-phenyl-1H-pyrrole-3-carboxylic Acid Ethyl Ester (8h)
Mp 112 °C (i-PrOH–H2O).
1H NMR: d = 1.16 (t, J = 7.2 Hz, 3 H, CH3), 3.64 (s, 2 H, SCH2),
3.75 (s, 3 H, OCH3), 3.76 (s, 3 H, OCH3), 4.10 (q, J = 7.2 Hz, 2 H,
OCH2), 4.28 (d, J = 6.0 Hz, 2 H, NCH2), 6.73 (dd, J3 = 8.4 Hz,
J4 = 1.6 Hz, 1 H, 6-HAlk), 6.79 (d, J = 8.4 Hz, 1 H, 5-HAlk), 6.83 (d,
J = 1.6 Hz, 1 H, 2-HAlk), 6.85 (d, J = 2.0 Hz, 1 H, 5-H), 7.19 (t,
J = 6.8 Hz, 1 H, Ar), 7.28 (m, 4 H, Ar), 8.69 (t, J = 6.0 Hz, 1 H,
CONH), 11.93 (br s, 1 H, NH).
Anal. Calcd for C22H21ClN2O3S: C, 61.60; H, 4.93; Cl, 8.27; N,
6.53; S, 7.48. Found: C, 61.41; H, 4.84; Cl, 8.07; N, 6.47; S, 7.65.
13C NMR: d = 14.3 (CH3), 39.3 (SCH2), 42.3 (NCH2), 55.0 (OCH3),
55.9 (OCH3), 59.1 (OCH2), 111.2 (2-CAlk), 113.0 (5-CAlk), 116.1 (3-
C), 121.2 (6-CAlk), 122.3 (5-C), 124.8 (4-C), 126.3 (4-CAr), 128.3
Synthesis 2004, No. 14, 2317–2322 © Thieme Stuttgart · New York

PAPER
N-Alkyl-2-(1H-pyrrol-2-ylthio)acetamides and -propanamides
2321
(2-C), 128.9 (3,5-CAr), 131.9 (2,6-CAr), 132.9 (1-CAr), 133.6 (1-
Alk), 146.5 (3-CAlk), 148.0 (4-CAlk), 166.3 (COO), 169.3 (CONH).
4-(4-Bromophenyl)-2-[(2-{[2-(4-methoxyphenyl)ethyl]amino}-
1-methyl-2-oxoethyl)thio]-1H-pyrrole-3-carboxylic Acid Ethyl
C
Ester (9c)
Mp 108 °C (i-PrOH–H2O).
Anal. Calcd for C24H26N2O5S: C, 63.42; H, 5.77; N, 6.16; S, 7.05.
Found: C, 63.69; H, 5.63; N, 5.99; S, 7.24.
1H NMR: d = 1.19 (t, J = 7.4 Hz, 3 H, CH3), 1.36 (d, J = 6.4 Hz, 3
H, CH3), 2.63 (m, 2 H, CH2), 3.25 (m, 2 H, NCH2), 3.73 (s, 3 H,
OCH3), 3.83 (q, J = 6.4 Hz, 1 H, SCH), 4.13 (q, J = 7.4 Hz, 2 H,
OCH2), 6.76 (d, J = 8.8 Hz, 2 H, Alk), 6.88 (d, J = 1.6 Hz, 1 H, 5-
H), 7.06 (d, J = 8.8 Hz, 2 H, Alk), 7.24 (d, J = 8.4 Hz, 2 H, Ar), 7.41
(d, J = 8.4 Hz, 2 H, Ar), 7.92 (t, J = 4.2 Hz, 1 H, CONH), 11.88 (br
s, 1 H, NH).
13C NMR: d = 15.7 (CH3), 17.2 (CH3), 34.0 (SCH), 43.7 (CH2), 49.0
(NCH2), 57.0 (OCH3), 61.0 (OCH2), 115.7 (3,5-CAlk), 116.4 (3-C),
117.8 (4-CAr), 121.0 (5-C), 125.0 (4-C), 128.0 (2,6-CAlk), 129.0 (2-
C), 129.8 (3,5-CAr), 131.1 (2,6-CAr), 132.7 (1-CAlk), 135.6 (1-CAr),
158.0 (4-CAlk), 165.0 (COO), 172.5 (CONH).
2-[(2-{[2-(4-Methoxyphenyl)ethyl]amino}-2-oxoethyl)thio]-4-
phenyl-1H-pyrrole-3-carboxylic Acid Ethyl Ester (8i)
Viscous oil (i-PrOH–H2O).
1H NMR: d = 1.17 (t, J = 7.2 Hz, 3 H, CH3), 2.69 (t, J = 7.2 Hz, 2
H, CH2), 3.32 (m, 2 H, NCH2), 3.55 (s, 2 H, SCH2), 3.74 (s, 3 H,
OCH3), 4.11 (q, J = 7.2 Hz, 2 H, OCH2), 6.78 (d, J = 8.0 Hz, 2 H,
Alk), 6.85 (d, J = 2.4 Hz, 5-H), 7.09 (d, J = 8.0 Hz, 2 H, Alk), 7.19
(t, J = 7.2 Hz, 1 H, Ar), 7.29 (m, 4 H, Ar), 8.29 (t, J = 5.6 Hz, 1 H,
CONH), 11.92 (br s, 1 H, NH).
13C NMR: d = 13.1 (CH3), 38.0 (SCH2), 41.7 (CH2), 46.1 (NCH2),
57.1 (OCH3), 61.0 (OCH2), 115.0 (3,5-CAlk), 115.6 (3-C), 121.0 (5-
C), 125.1 (4-C), 126.1 (4-CAr), 128.5 (2,6-CAlk), 128.6 (2,6-CAr),
129.2 (3,5-CAr), 129.4 (2-C), 132.9 (1-CAlk), 135.9 (1-CAr), 158.0
(4-CAlk), 165.5 (COO), 170.4 (CONH).
Anal. Calcd for C25H27BrN2O4S: C, 56.50; H, 5.12; Br, 15.03; N,
5.27; S, 6.03. Found: C, 56.55; H, 5.36; Br, 15.24; N, 5.43; S, 6.17.
4-(4-Chlorophenyl)-2-{[1-methyl-2-oxo-2-(benzylamino)eth-
yl]thio}-1H-pyrrole-3-carboxylic Acid Ethyl Ester (9d)
Mp 155 °C (EtOH).
Anal. Calcd for C24H26N2O4S: C, 65.73; H, 5.98; N, 6.39; S, 7.31.
Found: C, 65.64; H, 6.01; N, 6.39; S, 7.49.
4-(4-Bromophenyl)-2-{[1-methyl-2-oxo-2-(benzylamino)eth-
yl]thio}-1H-pyrrole-3-carboxylic Acid Ethyl Ester (9a)
Mp 154 °C (EtOH).
1H NMR: d = 1.18 (t, J = 7.0 Hz, 3 H, CH3), 1.42 (d, J = 7.2 Hz, 3
H, CH3), 3.94 (q, J = 7.2 Hz, 1 H, SCH), 4.11 (q, J = 7.0 Hz, 2 H,
OCH2), 4.25 (dd, J2 = 14.4 Hz, J3 = 5.2 Hz, 1 H, NCH2), 4.35 (dd,
J2 = 14.4 HZ, J3 = 5.2 Hz, 1 H, NCH2), 6.86 (s, 1 H, 5-H), 7.15–7.25
(m, 7 H, Alk, Ar), 7.40 (d, J = 8.0 Hz, 2 H, Ar), 8.38 (t, J = 5.2 Hz,
1 H, CONH), 11.87 (s, 1 H, NH).
13C NMR: d = 13.8 (CH3), 16.5 (CH3), 35.0 (SCH), 44.0 (NCH2),
57.8 (OCH2), 114.0 (3-C), 117.3 (4-CAr), 121.3 (5-C), 126.4 (4-C),
126.6 (4-CAlk), 127.0 (2,6-CAlk), 127.6 (2-C), 129.3 (3,5-CAlk),
130.0 (3,5-CAr), 133.1 (1-CAr), 133.8 (2,6-CAr), 137.7 (1-CAlk),
165.0 (COO), 171.5 (CONH).
1H NMR: d = 1.17 (t, J = 7.0 Hz, 3 H, CH3), 1.43 (d, J = 7.2 Hz, 3
H, CH3), 3.93 (q, J = 7.2 Hz, 1 H, SCH), 4.11 (q, J = 7.0 Hz, 2 H,
OCH2), 4.25 (dd, J2 = 14.8 Hz, J3 = 5.6 Hz, 1 H, NCH2), 4.36 (dd,
J2 = 14.8 Hz, J3 = 5.6 Hz, 1 H, NCH2), 6.82 (d, J = 3.2 Hz, 1 H, 5-
H), 7.17 (m, 3 H, Alk), 7.25 (m, 6 H, Alk, Ar), 8.35 (t, J = 5.6 Hz,
1 H, CONH), 11.84 (br s, 1 H, NH).
13C NMR: d = 15.0 (CH3), 18.7 (CH3), 32.9 (SCH), 40.9 (NCH2),
59.2 (OCH2), 115.0 (3-C), 122.7 (5-C), 126.3 (2,6-CAlk), 126.4 (4-
CAr), 128.4 (2-C), 128.5 (4-C), 129.1 (4-CAlk), 129.4 (3,5-CAlk),
131.3 (2,6-CAr), 131.4 (3,5-CAr), 135.0 (1-CAr), 139.8 (1-CAlk),
165.0 (COO), 169.0 (CONH).
Anal. Calcd for C23H23ClN2O3S: C, 62.36; H, 5.23; Cl, 8.00; N,
6.32; S, 7.24. Found: C, 62.39; H, 5.18; Cl, 7.83; N, 6.37; S, 7.16.
4-(4-Chlorophenyl)-2-[(2-{[(3,4-dimethoxyphenyl)methyl]ami-
no}-1-methyl-2-oxoethyl)thio]-1H-pyrrole-3-carboxylic Acid
Ethyl Ester (9e)
Anal. Calcd for C23H23BrN2O3S: C, 56.68; H, 4.76; Br, 16.39; N,
5.75; S, 6.58. Found: C, 56.72; H, 4.78; Br, 16.28; N, 5.55; S, 6.38.
Mp 83 °C (i-PrOH–H2O).
4-(4-Bromophenyl)-2-[(2-{[(3,4-dimethoxyphenyl)methyl]ami-
no}-1-methyl-2-oxoethyl)thio]-1H-pyrrole-3-carboxylic Acid
Ethyl Ester (9b)
1H NMR: d = 1.17 (t, J = 7.2 Hz, 3 H, CH3), 1.43 (d, J = 7.2 Hz, 3
H, CH3), 3.73 (s, 6 H, OCH3), 3.90 (q, J = 7.2 Hz, 1 H, SCH), 4.10
(q, J = 7.2 Hz, 2 H, OCH2), 4.17 (dd, J2 = 14.8 Hz, J3 = 5.2 Hz, 1 H,
NCH2), 4.28 (dd, J2 = 14.8 Hz, J3 = 5.2 Hz, 1 H, NCH2), 6.66 (d,
J = 8.4 Hz, 6-HAlk), 6.71 (d, J = 8.4 Hz, 5-HAlk), 6.78 (s, 1 H, 2-
HAlk), 6.82 (s, 1 H, 5-H), 7.25 (m, 4 H, Ar), 8.28 (t, J = 5.2 Hz, 1 H,
CONH), 11.83 (br s, 1 H, NH).
13C NMR: d = 12.3 (CH3), 17.8 (CH3), 35.7 (SCH), 44.4 (NCH2),
54.5 (OCH3), 54.6 (OCH3), 60.7 (OCH2), 111.4 (5-CAlk), 112.2 (2-
CAlk), 113.0 (3-C), 118.1 (5-C), 122.2 (6-CAlk), 124.9 (4-CAr), 126.2
(4-C), 126.3 (2-C), 130.4 (1-CAlk), 131.0 (2,6-CAr), 131.3 (3,5-CAr),
135.0 (1-CAr), 146.1 (3-CAlk), 149.4 (4-CAlk), 165.8 (COO), 166.8
(CONH).
Mp 79 °C (i-PrOH).
1H NMR: d = 1.16 (t, J = 7.2 Hz, 3 H, CH3), 1.40 (d, J = 6.4 Hz, 3
H, CH3), 3.71 (s, 3 H, OCH3), 3.72 (s, 3 H, OCH3), 3.90 (q, J = 6.4
Hz, 1 H, SCH), 4.10 (q, J = 7.2 Hz, 2 H, OCH2), 4.16 (dd, J2 = 14.8
Hz, J3 = 5.2 Hz, 1 H, NCH2), 4.25 (dd, J2 = 14.8 Hz, J3 = 5.2 Hz, 1
H, NCH2), 6.66 (d, J = 8.4 Hz, 1 H, 6-HAlk), 6.72 (d, J = 8.4 Hz, 1
H, 5-HAlk), 6.78 (s, 1 H, 2-HAlk), 6.86 (s, 1 H, 5-H), 7.20 (d, J = 8.4
Hz, 2 H, Ar), 7.39 (d, J = 8.4 Hz, 2 H, Ar), 8.32 (t, J = 5.2 Hz, 1 H,
CONH), 11.85 (br s, 1 H, NH).
13C NMR: d = 15.6 (CH3), 19.7 (CH3), 34.1 (SCH), 43.1 (NCH2),
54.2 (OCH3), 55.1 (OCH3), 60.9 (OCH2), 111.8 (2-CAlk), 113.5 (5-
CAlk), 116.7 (3-C), 119.0 (4-CAr), 121.8 (6-CAlk), 121.9 (5-C), 126.1
(2-C), 127.1 (4-C), 129.4 (2,6-CAr), 130.0 (3,5-CAr), 131.4 (1-CAlk),
136.1 (1-CAr), 148.3 (4-CAlk), 149.0 (3-CAlk), 163.0 (COO), 171.1
(CONH).
Anal. Calcd for C25H27ClN2O5S: C, 59.70; H, 5.41; Cl, 7.05; N,
5.57; S, 6.37. Found: C, 59.62; H, 5.37; Cl, 7.33; N, 5.32; S, 6.18.
4-(4-Chlorophenyl)-2-[(2-{[2-(4-methoxyphenyl)ethyl]amino}-
1-methyl-2-oxoethyl)thio]-1H-pyrrole-3-carboxylic Acid Ethyl
Ester (9f)
Anal. Calcd for C25H27BrN2O5S: C, 54.85; H, 4.97; Br, 14.60; N,
5.12; S, 5.86. Found: C, 55.03; H, 4.82; Br, 14.44; N, 5.14; S, 5.82.
Mp 113 °C (i-PrOH–H2O).
1H NMR: d = 1.18 (t, J = 7.0 Hz, 3 H, CH3), 1.38 (d, J = 6.4 Hz, 3
H, CH3), 2.63 (m, 2 H, CH2), 3.28 (m, 2 H, NCH2), 3.72 (s, 3 H,
OCH3), 3.81 (q, J = 6.4 Hz, 1 H, SCH), 4.12 (q, J = 7.0 Hz, 2 H,
Synthesis 2004, No. 14, 2317–2322 © Thieme Stuttgart · New York

2322
A. V. Tverdokhlebov et al.
PAPER
G.; Rebello, H. J. Org. Chem. 1987, 52, 1027. (c) Berree,
F.; Marchand, E.; Morel, G. Tetrahedron Lett. 1992, 33,
6155.
OCH2), 6.73 (d, J = 8.8 Hz, 2 H, Alk), 6.83 (s, 1 H, 5-H), 7.05 (d,
J = 8.8 Hz, 2 H, Alk), 7.24 (d, J = 8.4 Hz, 2 H, Ar), 7.28, (d, J = 8.4
Hz, 2 H, Ar), 7.86 (t, J = 4.6 Hz, CONH), 11.88 (s, 1 H, NH).
(6) (a) Yamazaki, C.; Katayama, K.; Suzuki, K. J. Chem. Soc.,
Perkin Trans. 1 1990, 3085. (b) Gotthardt, H.; Reiter, F.
Liebigs Ann. Chem. 1979, 650.
(7) (a) Ohsugi, E.; Fujioka, T.; Harada, H.; Nakamura, M.;
Maeda, R. Chem. Pharm. Bull. 1989, 37, 1268. (b) Kumar,
A.; Ila, H.; Junjappa, H. J. Chem. Soc., Chem. Commun.
1963, 3050. (c) Komkov, A. V.; Bogdanov, V. S.;
Dorokhov, V. A. Izv. Akad. Nauk Ser. Khim. 1996, 1808;
Russ. Chem. Bull.; 1996, 45: 1720.
13C NMR: d = 14.5 (CH3), 18.8 (CH3), 34.6 (SCH), 41.3 (CH2), 47.8
(NCH2), 55.5 (OCH3), 60.1 (OCH2), 114.3 (3,5-CAlk), 117.2 (3-C),
120.7 (5-C), 125.1 (4-C), 125.4 (4-CAr), 128.2 (2,6-CAlk), 130.1
(3,5-CAr), 130.5 (2,6-CAr), 131.1 (2-C), 131.7 (1-CAlk), 134.5 (1-
CAr), 158.2 (4-CAlk), 164.8 (COO), 171.7 (CONH).
Anal. Calcd for C25H27ClN2O4S: C, 61.66; H, 5.59; Cl, 7.28; N,
5.75; S, 6.58. Found: C, 61.89; H, 5.51; Cl, 7.07; N, 5.65; S, 6.39.
(8) Beveridge, S.; Harris, R. L. N. Austr. J. Chem. 1971, 24,
1229.
References
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(10) Tverdokhlebov, A. V.; Resnyanska, E. V.; Tolmachev, A.
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Builla, J. J. Heterocycl. Chem. 1986, 23, 1889.
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