Structure-activity relationship studies of a novel series of anthrax lethal factor inhibitors

Article abstract of DOI:10.1016/j.bmc.2009.03.040

We report on the identification of a novel small molecule inhibitor of anthrax lethal factor using a high-throughput screening approach. Guided by molecular docking studies, we carried out structure-activity relationship (SAR) studies and evaluated activi

Full text of DOI:10.1016/j.bmc.2009.03.040

Bioorganic & Medicinal Chemistry 17 (2009) 3352–3368
Contents lists available at ScienceDirect
Bioorganic & Medicinal Chemistry
journal homepage: www.elsevier.com/locate/bmc
Structure–activity relationship studies of a novel series of anthrax lethal
factor inhibitors
Sherida L. Johnson a, Li-Hsing Chen a, Elisa Barile a, Aras Emdadi a, Mojgan Sabet b, Hongbin Yuan a, Jun Wei a,
Donald Guiney b, Maurizio Pellecchia a,
*
a Burnham Institute for Medical Research, Cancer Research Center and Infectious and Inflammatory Disease Center, 10901 North Torrey Pines Rd, La Jolla, CA 92037, USA
b Department of Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
a r t i c l e i n f o
a b s t r a c t
Article history:
We report on the identification of a novel small molecule inhibitor of anthrax lethal factor using a high-
throughput screening approach. Guided by molecular docking studies, we carried out structure–activity
relationship (SAR) studies and evaluated activity and selectivity of most promising compounds in in vitro
enzyme inhibition assays and cellular assays. Selected compounds were further analyzed for their in vitro
ADME properties, which allowed us to select two compounds for further preliminary in vivo efficacy
studies. The data provided represents the basis for further pharmacology and medicinal chemistry opti-
mizations that could result in novel anti-anthrax therapies.
Received 6 January 2009
Revised 13 March 2009
Accepted 20 March 2009
Available online 26 March 2009
Keywords:
LF
Anthrax toxin
Ó 2009 Elsevier Ltd. All rights reserved.
Metalloprotease inhibitor
1. Introduction
cleaves MEK1, MEK2, MKK3 and MKK6 at one site while MKK4
and MKK7 are cleaved at two different sites.7
Anthrax lethal factor has become an attractive drug target due
to its relevance to the pathogenesis of Bacillus anthracis, a bioter-
rorism agent.1 B. anthracis, a rod shaped bacterium which infects
humans through the respiratory system, skin, or digestive tract
can be highly lethal depending upon its entry route into the human
body. Although cutaneous anthrax is rarely lethal, inhalation an-
thrax is dangerous and usually fatal.2 The bacteria release a toxin
that kills host macrophages, consisting of three virulence factors:
protective antigen (PA, 83 kDa), edema factor (EF, 89 kDa) and
lethal factor (LF, 90 kDa). It has been shown that bacterial strains
lacking LF are not lethal in mice.3–6 Hence, lethal factor (LF), a
Zn2+-metalloprotease, plays a critical role in the cleavage of several
members of the MAPKK family near their N-terminus. This cleav-
age prevents interaction with, and phosphorylation of, down-
stream MAPK, thereby inhibiting one or more signaling pathways
leading to cell death in macrophages. The MAPKK family has seven
members, two MEKs (MAPK/ERK (extracelluar-signal-regulated ki-
nase) Kinase) 1 and 2 (MEK1, MEK2) and five MKKs (MKK3, MKK4,
MKK5, MKK6 and MKK7). MEK1 and MEK2 specifically phosphory-
late and activate the ERK1 and ERK2 MAPKs. MKK3 and MKK6 are
specific for the MAP kinase p38hog, where MKK4 and MKK7 phos-
phoactivate the stress-activated protein kinase JNK (c-Jun N-termi-
nal kinase), although MKK4 can also phosphorylate p38hog. LF
With the threat of lethal anthrax spores being used as a biolog-
ical weapon, the current treatment includes administration of
appropriate antibiotics usually prior to the occurrence of symp-
toms. Although antibiotics such as ciprofloxacin are effective
against B. anthracis, high levels of secreted toxin may remain in cir-
culation for several days which continues to damage the host even
after the bacteria may have been killed.6 Moreover, the current an-
thrax vaccine approved by the FDA for human use in the United
States is AVA (anthrax vaccine adsorbed), which consists of a B.
anthracis culture supernatant that has been adsorbed onto an alu-
minum adjuvant. By stimulating antibodies against PA, this vaccine
has shown to provide protection in animal models of anthrax.
However, humans treated with AVA requires six administered
doses within an 18 month time period, along with annual booster
immunizations, which is not an ideal dose regimen if there should
be a need for rapid vaccination before or in response to bioterrorist
events. Thus a combination of antibiotics and toxin inhibitors has
been proposed as a rational approach for developing a more rapid
response against anthrax. Since LF has been shown to act as the key
virulence factor, much work has been focused on finding potent
inhibitors of LF. Currently there are several potent LF inhibitors,
in which some have been identified in our laboratory, however,
only a few of these inhibitors are significantly effective in in vivo
models. Therefore it is important that LF inhibitors not only inhib-
its the cleavage of MAPKK, but also are able to be bioavailable and
to enter and remain active in cells since LF functions in the cytosol.
* Corresponding author. Tel.: +1 858 646 3159; fax: +1 858 713 9925.
E-mail address: mpellecchia@burnham.org (M. Pellecchia).
0968-0896/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved.
doi:10.1016/j.bmc.2009.03.040

S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
3353
crystal structure by Shoop et al.13 consisting of compound 7 in
complex with LF (PDB: 1YQY) (Fig. 2). Shoop et al. demonstrated
in the X-ray structure that compound 7 coordinated to the Zn2+
atom via the hydroxymate moiety, the thiophene group for com-
pound 5 aligns similarly allowing us to preclude that the thiophene
is coordinating the Zn2+ atom.
2. Results and discussion
The LF inhibitors identified thus far contain key Zn2+-chelating
moieties7 such as a hydroxymate,8–13 polyphenols/catechol,14,15
penicillin based,16 rhodanine,17,18,14,6,19 aminoglycoside,20–22 quin-
oline urea23 and hydrazone.24,25 In this study, we present the iden-
tification of a novel scaffold shown to inhibit LF in vitro and in cell.
This scaffold was identified via screening a diverse chemical library
Initially, we synthesized compound 5, tested it to validate its ki-
netic activity and closely examined its predicted binding in the cat-
alytic site of LF (Fig. 2). In comparing the interactions of
compounds 5 and 7 in the LF catalytic site, we observed that their
mode of binding was similar, in which the hydroxymate of com-
pound 7 chelating the zinc is represented by the thiophene moiety
in compound 5, with the remaining sub-structures occupying sim-
ilar subsites (Fig. 2). Based on the proposed docking geometry, we
decided to perform structure–activity relationship studies in which
we first explored changes amongst the sulfonylamide group to
determine its relevance in binding to LF, (Table 2), with or without
a methyl group at the fourth position of the thiophene ring (Tables
3 and 4). We further dissected this scaffold by exchanging the thi-
ophene ring with an isooxazole, a benzene ring, an ethyl group or
completely eliminating the thiophene group (Table 5). The synthe-
sis of analogues which lacked the benzothiazole moiety was also
carried out (Table 6) as well as the synthesis of disubstituted sul-
fonamides (Table 7).
TM
of 16,000 drug-like molecules (HitFinder , Maybridge, Morris
Plains, NJ) utilizing high-throughput fluorescence microplate as-
says as previously described.17,14,18 Kinetic studies of the most po-
tent LF inhibitors with >50% inhibition at 20 lM, were performed
and IC50 and Ki values were obtained by dose response measure-
ments. A total of six compounds (Table 1) gave IC50 values ranging
between 3 and 19
lM. Considering the ease of synthesis and
guided by docking studies, we decided to focus on compound 5
(Table 1). Molecular modeling studies revealed that the docked
geometry of compound 5 could fit well with the redocked molecu-
lar model of compound 7 from the previously published X-ray
Table 1
Chemical structure and inhibitory activity of 6 hit compounds from the HTS campaign
against lethal factor (LF)
The syntheses of these compounds were carried out under nor-
mal sulfonamide coupling conditions using pyridine as the solvent
except for the disubstituted sulfonamides in which we used dichlo-
romethane and triethylamine.26 The compounds were obtained
with average yields of 65–80% and purity of at least 95% for key
compounds. Once synthesized and characterized, we then per-
formed an enzymatic assay to evaluate the inhibitory activity of
the resulting compounds against LF. The fluorescence peptide
#
Structure
IC50 (Ki) (lM)
O
S
O
OH
H
N
1
3.4 (0.56)
NH2
OH
H2N
H
N
N
cleavage assay was performed in a 96 well plate (100
lL/well) as
we previously reported.19 For a number of compounds, including
the six original hits, a Lineweaver–Burk analysis was also carried
out to verify that the compounds are competitive against the sub-
strate (Fig. 1).
O
O
2
4.2 (5.9)
O
O
From the data reported in Table 2 (benzothiazole-4-methylthi-
ophene derivatives, BTMT), we first compared the lead compound
5 (Table 1) with compounds 8 and 9 and observed a loss in activity
for the molecules lacking a sulfonylaryl moiety or an electron with-
drawing substituent on the sulfonylaryl group. However, it seems
that the position of the substituents is critical for optimal binding.
For instance, if we take compounds 10 and 11, which have a tri-
fluoromethyl group in the meta or ortho position, respectively,
compound 10 is 10 times more potent than compound 11. A sim-
ilar trend was also observed with compounds which contained a
substituent in the para position (compounds 12, 13, 14, 15), meta
position (compounds 32 and 33) or disubstituted para/meta posi-
tion (compounds 19, 20, 21 and 24). Here the meta or disubstituted
analogues showed improved inhibitory properties with the excep-
tion of compounds 23 and 31. Overall, the most potent compounds
of the BTMT series were compounds 21 and 10 which gave IC50 val-
O
N
O
3
4.8 (0.38)
N
NH
HN
F
F
F
S
NH
N
HN
S
O
4
5
6
12 (5.0)
15 (7.8)
19 (6.6)
S
ues of 8.9 and 9.4 lM, respectively.
As part of the evaluation of the SAR at the sulfonylamide moi-
ety, replacement of BTMT with benzothiazole thiophene (BTT) re-
tained enzyme potency while reducing the molecular weight of
the compounds (Tables 3 and 4). Initially, we showed that a com-
pound lacking the sulfonylaryl moiety, (compound 42), was essen-
tially inactive. However, reintroducing a sulfonylbenzene moiety
N
S
S
HN
O
O
S
(compound 43) leads to an activity with an IC50 value of 39
lM.
Cl
O
Comparison of the IC50 values of compounds 43 and 9 (Table 2) re-
vealed that the BTT series may lead to more potent inhibitors.
Analysis of the IC50 values with the within the BTT series, did not
reveal a clear trend regarding the role of the positioning of the sub-
stituents. However, compounds that were disubstituted in the
N
O2N
S
O

3354
S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
100
75
50
25
0
100
75
50
25
0
0.1
1
10
100
0.1
1
10
100
Inhibitor concentration, (μM)
Inhibitor concentration, (μM)
10-3
10-3
10-4
10-4
10-4
0
6.0×
5.0×
4.0×
3.0×
2.0×
1.0×
10-4
1.5×
1.2×
9.0×
6.0×
3.0×
10-4
10-4
10-4
10-4
10-4
0
0.0
0.5
1.0
0.0 0.2 0.4 0.6 0.8 1.0
1/[S]
1/[S]
Figure 1. Kinetics of inhibition of lethal factor (LF) for compounds 70 and 71. IC50 evaluation of (A) compound 70 and (B) compound 71 against LF; C) Ki evaluation of
compound 70 at 10
lM; (red line; Ki = 1.01
l
M); the black dashed line represents DMSO. D) Ki evaluation of compound 71 at 6 lM; (red line; Ki = 1.7 lM); the black dashed
line represents DMSO.
O
N
S
S
O
S
O
H
N
HN
O
O
CH3
F
HO
N
H
S
O
Compound 7
Compound 5
Cl
Zn
Zn
His690
His690
His686
His686
Figure 2. Molecular modeling studies; (A) Chemical structure of compound 5. (B) Chemical structure of Compound 7. (C) Detail of the redocked geometry of compound 7
from the X-ray coordinates in complex with LF (PDB: 1YQY).13 Side chain residues His690 and His686 and the catalytic Zn2+ from LF are displayed. (D) Docked geometry of
compound 5 in the catalytic site of LF. (E) Superimposition of compounds 5 (ball and stick model) and 7 (thin line model).

S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
3355
Table 2
Benzothiazole-4-methylthiophene (BTMT) derivatives and IC50 values against lethal factor (LF)
N
S
S
HN
O
S
O
R
#
R
IC50
(
lM)
#
R
IC50 (lM)
8
Ha
>100
>100
25
>100
>100
Cl
Cl
9
26
27
Cl
F
CF3
10
9.4
100
F3C
H3C
Cl
11
12
13
14
>100
28
29
30
31
100
48
NO2
CH3
CF3
Cl
18
46
OCF3
11
OCH3
CH3
Cl
>100
>100
OCF3
OCH3
15
16
>100
14
32
33
11
11
F
NHAc
NO2
17
18
11
19
34
35
12
17
F
Cl
F
19
20
21
35
17
36
37
38
21
12
16
OCH3
Cl
CH3
CH3
F
Cl
8.9
OCH3
CH3
Cl
Cl
22
15
39
22
Cl
Cl
Cl
CF3
23
24
>100
34
40
41
17
19
F
CF3
OCH3
OCH3
a
Free amine.

3356
S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
Table 3
Benzothiazole thiophene (BTT) derivatives and IC50 values against lethal factor (LF)
N
S
S
HN
O
O
S
R
#
R
IC50
(lM)
#
R
IC50
13
(lM)
42
Ha
>100
39
59
Cl
Cl
Cl
43
44
60
61
9
Cl
F
CF3
16
30
F3C
H3C
45
46
9.3
9.6
62
63
>50
10
NO2
CH3
CF3
Cl
OCH3
47
48
49
18
64
65
66
10
15
8
OCH3
CH3
F
13
16
Cl
50
51
24
11
67
68
11
8
NHAc
CF3
Cl
Br
F
52
18
69
28
CH3
Cl
F
53
54
11
12
70
71
3.8
3.0
3.9
OCH3
Cl
CH3
CH3
F
Cl
55
56
6.6
72
73
OCF3
CH3
O
CF3
39
13
14
F3C
OCH3
O
Cl
57
58
74
18
Cl
Cl
F
OCH3
OCH3
19
75
7.2
Cl
Cl
Cl
123
4.5
124
3.0
Br
OCH3
a
Free amine.

S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
3357
Table 4
Benzothiazole thiophene (BTT) heterocyclic derivatives and IC50 values against lethal factor (LF)
N
S
S
HN
O
O
R
S
#
R
IC50
13
(lM)
#
R
IC50
11
(lM)
CH3
N
N
76
89
H3C
77
78
8
9
90
91
22
30
CF3
O
OCH3
OCH3
N
O
N
S
N
79
80
81
82
83
84
85
9
>50
43
12
13
25
8
92
93
94
95
96
97
98
10
27
27
23
10
19
14
O
O
Cl
O
O
O
OCH3
N
N
N
O
O
N
S
N
H3C
N
O
S
CH3
O
N
S
N
N
N
N
O
Cl
S
N
HN
O
N
O
S
O
S
N
CH3
N
86
87
88
>50
17
99
100
101
18
>50
19
S
CH3
O
S
O
N
O
O
CH3
N
O
N
S
12
O
CH3
para/meta position versus monosubstitution in the meta or para po-
sition appeared overall more potent (compounds 44, 48, 49, 65, 66,
67, 53, 54, 57, 63 and 64) with the exception of compounds 47 and
58. This observation resulted in the design and synthesis of com-
nylsufonyl groups that overall seem to be more potent. The most
noticeable improvements were observed with compounds 70, 71
and 72, giving IC50 values of 3.8, 3.0 and 3.9 lM, respectively.
Based on the SAR analysis discussed above, we subsequently syn-
thesized the 30,40-disubstituted biphenyl derivatives that however
led to compounds which are slightly less active (compounds 75
and 78). Within the BTT series we also observed that disubstitution
at the meta/para position, where the meta position had a chlorine
pound 55 which indeed has an improved IC50 value of 6.6 lM.
On the contrary, disubstitution at the ortho/meta or ortho/para po-
sition led to compounds that lost activity dramatically (compounds
56, 61, 62). Further, we synthesized compounds containing biphe-

3358
S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
Table 5 (continued)
Table 5
Benzothiazole derivatives and IC50 values against lethal factor (LF)
#
Structure
IC50 (lM)
#
Structure
IC50 (lM)
NH
S
N
S
O
N
S
NH
S
O
O
O
102
28
109
>50
Cl
CH3
OCH3
N
S
NH
S
O
NH
S
N
S
O
O
O
103
>50
110
>50
OCH3
Cl
N
S
N
S
NH
S
O
O
HN
O
O
104
>50
S
111
>100
Cl
OCH3
N
S
N
S
S
HN
O
O
HN
O
S
O
S
112
100
105
>50
Cl
OCH3
group, led to improved activity (compounds 49 vs 57, 48 vs 55, 65
vs 60, 68 vs 123). Based on these observations, we synthesized the
3-chloro-4-disubstituted biphenyl derivative 124, in which the
inhibitory activity against LF was slightly improved when com-
pared to the related compound 70. Moreover, the synthesis of
BTT analogues with various heterocyclicsulfonyl moieties did not
lead to compounds with increased affinity against LF (Table 4).
Finally, the substitution of the thiophene ring (Table 5) with
various groups or its elimination resulted in compounds that lack
significant inhibitory activity against LF. Similarly, compounds in
which we eliminated the benzothiazole ring (Table 6), showed no
N
S
S
HN
O
O
S
106
>50
Cl
S
N
N
O
inhibition at 50 lM, as well as the disubstituted sulfonylbenzene
HN
O
O
derivatives (Table 7). Overall, in comparing the BTT series with
the BTMT series, we found that in most cases the binding affinity
is significantly improved in the former series, with the exception
of just a few compounds. Furthermore, we also found that most ac-
S
107
>100
tive compounds against LF did not inhibit (up to 100 lM) human
matrix metalloproteases MMP-2 and MMP-9, the most closely re-
OCH3
lated human proteases to LF.19,14,18
S
N
N
O
In order to assess the efficacy of the compounds in a cellular
context, we measure the ability of most potent LF inhibitors to pro-
tect macrophages from LF/PA induced cell death.19 As shown in Ta-
ble 8, compound 70 gave an IC50 value of 506 nM in this assay,
while compounds 71, 93 and 55, and gave IC50 values of 251 nM,
HN
O
O
S
108
>100
1.6 lM and 1 lM, respectively. Hence we identified selective and
potent LF inhibitors which are effective in protecting human mac-
rophages from anthrax toxin. In order to evaluate whether these
compounds are likely to be effective in vivo, we first measured crit-
Cl

S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
3359
Table 6
Table 7
Thiophene derivatives and IC50 values against lethal factor (LF)
Disubstituted benzothiazole thiophene derivatives and IC50 values against lethal
factor (LF)
#
Structure
IC50
Structure
IC50
S
N
S
HN
O
O
S
113
S
S
>50
O
S
O
Cl
N
O
O
120
>100
S
CH3
F3C
F3C
S
HN
O
O
N
S
114
>50
S
O
S
N
O
121
>100
S
F3CO
O
O
OCH3
OCF3
S
N
HN
O
O
S
S
S
O
S
O
115
>50
N
O
122
>100
S
F
O
F
Cl
Cl
O
S
S
studies, we were able to design an inhibitor against LF, which
shows to be effective in macrophages and lack cytotoxicity. We
were also able to show selectivity amongst MMP-2 and -9 and
show that with a single daily dose of LF inhibitor we were able
to observe some protection using in vivo mice models of anthrax.
Thus pharmacokinetic studies of compounds 55 and 70 are
underway.
NH
O
116
>100
CH3
O
S
S
NH
O
117
118
119
>100
>100
>100
CF3
CH3
3. Methods and materials
3.1. Reference compounds and reagents
O
S
O
S
S
NH
NH
Reference compounds 8 and 42 were purchased from Ryan Sci-
entific. All common chemicals, reagents, and buffers were pur-
chased from Sigma–Aldrich (St. Louis, MO), Acros Organics (Geel,
Belgium) or Maybridge (Morris Plains, NJ). Recombinant LF and
MAPKKideÒ were purchased from List Biological Laboratories
(Campbell, CA). The MMP-2 and MMP-9 assay kits were purchased
from Anaspec, Inc. (San Jose, CA). Synthetic details of the benzothi-
azole derivatives are described in the methods and materials
section. Characterization of each benzothiazole derivative was ob-
tained by means of NMR spectroscopy. Elemental analysis was per-
formed for compounds 70, 72, 92 and HR/MS and HPLC purity was
performed for compounds 10, 16, 17, 20, 21, 22, 30, 32, 33, 34, 35,
37, 38, 40, 44, 45, 46, 48, 49, 51, 53, 54, 55, 57, 59, 60, 63, 64, 65, 66,
67, 68, 71, 72, 73, 75, 77, 78, 79, 82, 83, 85, 87, 88, 89, 92, 98, 123,
124 (Tables 9 and 10).
CF3
O
S
O
ical in vitro parameters such as chemical stability, plasma stability,
microsomal stability, solubility and cell permeability (Table 8).
From these data, we concluded that except for solubility, com-
pounds 70 and 55 were the most suited candidates for preliminary
in vivo efficacy studies (Fig. 3). Preliminarily, when administered
via intraperitoneal injection (daily at 25 mg/kg), compound 70
seemed to be a little more effective in protecting the mice after
8 days of post infection compared to compound 55. While the ob-
served protection with compound 70 is significant, further studies
aimed at the determination of proper formulation of the compound
(to increase solubility) and pharmacokinetics (to assess dose and
regimen) must be conducted to improve the efficacy of the
inhibitor.
3.2. Enzymatic assays
3.2.1. MAPKKideÒ assay
The fluorescence peptide cleavage assay was performed in a 96
well plates (100
MAPKKideÒ (4
20 mM Hepes, pH 7.4, and the screening compounds (mixture of
20; each compound at 10 M). Kinetics of the peptide cleavage
was examined for 30 min by using a fluorescent plate reader (Vic-
l
L/well) in which each reaction mixture contained
lM) and LF (50 nM) (List Biological Laboratories) in
In conclusion, we have generated and validated a novel series of
LF inhibitors with low- to sub-micromolar activity. By using SAR
l

3360
S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
Table 8
In cell data along with in vitro ADME experiments for selected LF inhibitors
R2
N
S
S
HN
O
O
S
R1
#
R1
R2
H
IC50 (Ki) kinetic
EC50
Chem. stability (%)
84
LogS (Ug/mL)
Pampa
Low
Metabolic stability Hept.
Plasma stability (%)
99
70
3.8 (1.0)
506 nM
<10a
<10a
>100
>100
<10a
t1/2 = >120 min CLint = 3.6
OCH3
71
92
55
17
H
3.0 (1.7)
10.0
251 nM
ND
99.9
99
Low
t1/2 = >120 min CLint = –
t1/2 = >120 min CLint = 3.9
t1/2 = >120 min CLint = –
t1/2 = >120 min CLint = 0.6
100b
90
Cl
S
N
H
1.6
1.0
ND
l
M
M
High
High
High
Cl
H
6.6
l
100
100
CH3
CH3
11.0
99
NO2
ADME experiments conducted according to the protocols at Asinex Corporation, Moscow, Russia, http://asinex.com).19
ND = Not determined.
a
This compound is insoluble at 500
Results for 15 min.
lM.
b
N-terminal
MEK1
β-actin
100
80
60
40
20
0
1
2
3
4
5
6
7
8
Days post-infection
Figure 3. In cell and in vivo mice studies of the inhibition of lethal factor (LF) for compounds 70 and 55. (A) Macrophage assay for the inhibition of LF for compound 70
(EC50 = 561 nM). (B) Effect of test compounds on LF cleavage of MEK1. (Left panel) HeLa cells were incubated with a mixture of LF, PA83, and different concentrations of LF
inhibitors (inhibitor 1 at 300 lM; compound 7, inhibitor 2, 3, 4 at 30 lM; compound 70 at 100 lM). After 90 min, cells were lysed and protein lysates were subjected to SDS/
PAGE and to immunoblotting with an anti-MEK1 antibody, specific for the N-terminus of MEK1. b-Actin was immunoblotted as loading control. Inhibitor 3 and compound 70,
along with known inhibitors 1 and compound 7, are effective in protecting HeLa cells against LF cleavage of MEK1. Two weaker LF inhibitors 2 and 4 partially prevent the
MEK1 cleavage. (Right panel) Controls included untreated cells (–) and LF-PA-only treated cells. The data show that MEK1 cleavage is complete after 90 min of LF-PA addition.
(C) Compounds 70 and 55; protection of A/J mice from anthrax. Mice given DMSO alone were used as control and all died on day 7 (blue line). The group treated with
compound 70 (violet line) had the best survival (p < 0.01 compared to control group) while the group receiving compound 55 had slight improvement in comparison to the
control (p < 0.05).
tor V, Perkin Elmer, Waltham, MA) at excitation and emission
wavelengths of 485 and 535 nm, respectively, and IC50 values were
obtained by dose response measurements. For selected com-
pounds, Lineweaver–Burk analysis was also carried out to verify
that the compounds are competitive against the substrate. The
Km and Vmax values of the MAPKKideÒ cleavage by LF were deter-
mined at 25 °C by using the same experimental condition de-
scribed above for the fluorescence screening assay but with
increasing MAPKKideÒ concentrations (10, 5, 2.5
lM). The Ki and
Km(app) were calculated at 5 and/or 10
lM inhibitor concentration.

S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
3361
Table 9
Elemental analysis of compounds 70, 72, 92
#
Formula
C (%)
H (%)
N (%)
S (%)
Calcd
Found
Calcd
Found
Calcd
Found
Calcd
Found
70
72
92
C24H18N2O3S3
C24H15F3N2O3S3
C18H11N3O2S4
60.23
54.12
50.33
59.86
55.03
49.23
3.79
2.84
2.58
4.13
3.46
2.49
5.85
5.26
9.78
6.15
5.21
9.83
20.10
18.06
20.10
19.74
15.99
28.97
Table 10
HRMS analysis and HPLC purity for compounds 10, 16, 17, 20, 21, 30, 33–35, 38, 40, 44, 45, 48, 51, 53, 55, 59, 60, 63, 64, 66–68, 71, 72, 75, 77, 78, 82, 85, 88, 89, 92, 123, 124
#
ESI [MꢁH+] m/z
HPLC purity (%)
#
ESI [MꢁH+] m/z
HPLC purity (%)
Calcd
Found
Calcd
Found
10
16
17
20
21
30
33
34
35
38
40
44
45
48
51
53
55
59
455.0164
444.0505
432.0141
419.0352
435.0057
488.9774
417.0396
437.0447
463.0603
493.0709
599.0351
441.0008
441.0008
387.0290
441.0008
405.0196
420.9900
429.0760
455.0167
444.0509
432.0137
419.0356
435.0051
488.9781
417.0389
437.0447
463.0602
493.0711
599.0350
441.0006
441.0011
387.0295
441.0008
405.0199
420.9907
429.0751
99.5
98.7
99.7
99.3
98.9
99.3
99.8
99.8
95.4
98.9
97.1
97.3
98.5
99.2
98.5
98.0
98.7
99.1
60
440.9354
432.0141
474.9618
423.0290
456.9900
450.9239
483.0057
533.0270
516.9667
517.0320
509.0658
455.9963
439.0352
465.0508
467.0665
429.9807
484.8849
513.0163
440.9364
432.0145
474.9616
423.0300
456.9900
450.9244
483.0057
533.0271
516.9671
517.0317
509.0658
456.9913
439.0347
465.0503
467.0666
429.9819
484.8856
513.0162
99.0
95.0
95.5
98.1
95.0
95.0
99.9
95.8
95.0
99.1
99.4
91.0
95.9
97.2
99.1
97.5
99.3
99.2
63
64
66
67
68
71
72
75
77
78
82
85
88
89
92
123
124
3.2.2. MMP-2 and -9 assay
This assay was performed as outlined in the Anaspec MMP As-
say kit (Cat. No. 71151/71155). The fluorescence peptide cleavage
was normalized to control cells which were treated with the vehi-
cle, DMSO.
assay was performed in a 96 well plate (50
l
L/well) in which each
3.2.5. MEK1 cleavage assay
reaction mixture contained 5-FAM/QXLTM520 (60
1:100 in assay buffer) and MMP-2 or MMP-9 (10
l
L; diluted
3.2.5.1. Reagents. Inhibitor 1 (GM6001, Ilomastat) purchased
from United States Biological. (Swampscott, MA); Inhibitor 3 is a
known LF inhibitor as described in our previously published pa-
per.19 Inhibitors 2 and 4 have been synthesized in our laboratories
and will be described in a proceeding manuscript. The N-terminal
MEK1 antibody (anti-MEK1, N-terminal) was obtained from
Calbiochem (San Diego, CA) and the b-actin antibody (Monoclo-
nal-Anti-b-actin) was purchased from Sigma. Anti-rabbit and
anti-mouse-horseradish peroxidases were purchased from GE
Healthcare (UK).
l
g/mL; pro-
MMP-2 and -9 are first activated with 1 mM APMA for 20 min or
TM
2 h, respectively) in Enzolyte 520 MMP-2 assay buffer and the
screening compounds at 20
lM. Kinetics of the peptide cleavage
was examined every 5 min for 30 min by using a fluorescent plate
reader (Victor V, Perkin Elmer, Waltham, MA) at excitation and
emission wavelengths of 485 and 535 nm, respectively, and % inhi-
bition values were obtained.
3.2.3. ADME studies
In vitro ADME studies were conducted for selected compounds
(Table 8) according to the protocols at Asinex Corporation (Mos-
cow, Russia, www.asinex.com).19
3.3. Cell culture/assay
HeLa (Human cervical carcinoma) cells were obtained from the
American Type Culture Collection (Manassas, VA) and were cul-
tured in Dulbecco’s Modified Eagle Medium (DMEM, Cellgro) sup-
plemented with 10% fetal bovine serum (FBS, Omega Scientific;
Tarzana, CA) and 1% penicillin/streptomycin (Omega Scientific,
Tarzana, CA) at 37 °C in a humidified incubator containing 5% CO2.
Triplicate samples of approximately 2 ꢀ 104 HeLa cells were
plated in individual wells of a 48-well plate and incubated for
48 h. The cells were exposed, for 90 min at 37 °C, to a pre-incu-
bated solution of 2.5 ꢀ 10ꢁ8 M PA83, 5 ꢀ 10ꢁ9 M LF and different
concentrations of test compounds in serum-free DMEM medium.
The analyzed inhibitors were dissolved in DMSO reaching a final
DMSO concentration of 1%. Controls included untreated cells and
LF-PA-only treated cells at different time points (45 and 90 min).
Cells were later lysed and directly collected with reducing gel sam-
ple buffer and analyzed for MEK1 cleavage by immunoblotting as
previously described.27
3.2.4. Cell-based assay
Murine monocyte macrophage cells RAW 264.7 were seeded
45,000 cells per well in 96-well plates 24 h prior to treatment. Cells
were seeded and maintained in Hyclone DMEM (4500 mg/L Glu-
cose, 110 g/L Sodium Pyruvate) supplemented with 5% fetal bovine
serum, 2 mM Glutamax (Invitrogen, Carlsbad, CA). Cells are replen-
ished with fresh medium (0.1 mL/well). Cells were treated with
increasing concentrations of inhibitor (from 0.3 to 30
h. A hydroxamate inhibitor of the LF metalloproteinase activity,
GM6001 (Ki = 5 M) is included in the assay as a control. Anthrax
lM) for 2
l
protective-antigen-83 (PA83) and lethal factor (LF) are added to
the final concentrations of 500 ng/mL and 35 ng/mL, respectively.
After incubation for 4 h, cell viability was assessed using ATPlite
Assay from Perkin Elmer (Waltham, MA). Each datum point repre-
sents triplicates of each concentration in one experiment. Viability

3362
S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
3.4. Animal procedure
7.59 (dist. t, 1H, J = 6.9 Hz) 7.45 (dist. t, 1H, J = 6.9 Hz), 6.47 (s,
1H), 2.53 (s, 3H).
Mice (eight animals per group) were infected intranasally with
4 ꢀ 105 B. anthracis Sterne spores. Treatment with compound 70 or
55 (25 mg/kg daily in DMSO administered via intraperitoneal
injection) was started 24 h postexposure and continued for the
next 8 days. Mice given DMSO alone were used as the control
and all died on day 7 (blue line). The group treated with compound
70 had the best survival (p < 0.01 compared to control group) while
the group receiving compound 55 had slight improvement in com-
parison to the control (p < 0.05).
3.7.1.4. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-4-
(trifluoromethoxy)benzenesulfonamide (12). 1H NMR (300
MHz, CDCl3-d) d 8.08 (d, 1H, J = 8.1 Hz), 7.89 (dist. t, 3H, J = 9.3,
9.0 Hz), 7.58 (d, 1H, J = 8.1 Hz), 7.45 (t, 1H, J = 8.1 Hz), 7.12 (d,
2H, J = 8.1 Hz), 6.56 (s, 1H), 2.52 (s, 3H).
3.7.1.5. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-4-
methoxybenzenesulfonamide (13). 1H NMR (300 MHz, CDCl3-d)
d 8.08 (d, 1H, J = 7.8 Hz), 7.90 (d, 3H, J = 7.8 Hz), 7.81 (d, 1H,
J = 9.0 Hz), 7.57 (dist. t, 1H, J = 7.2 Hz), 6.99 (dist. t, 2H, J = 7.2 Hz),
6.79 (d, 1H, J = 9.0 Hz), 6.52 (s, 1H), 3.77 (s, 3H), 2.52 (s, 3H).
3.5. Molecular modeling
Docking studies were performed with GOLD28–30 and analyzed
with Sybyl and Benchware 3D Explorer (Tripos, St. Louis). The X-
ray coordinates of Lethal Factor PDB code 1YQY13 and 1PWQ10
were used to dock the compounds. For each compound, 20 solu-
tions were generated and subsequently ranked according to Chem-
score.30 Top solutions were used to represent the docked geometry
of the compounds and compared with the X-ray coordinates of
compounds previously reported.
3.7.1.6. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-4-
methylbenzenesulfonamide (14). 1H NMR (300 MHz, CDCl3-d) d
8.09 (d, 1H, J = 8.1 Hz), 7.90 (d, 1H, J = 8.1 Hz), 7.75 (d, 2H,
J = 8.1 Hz), 7.57 (t, 1H, J = 7.2 Hz), 7.43 (dist. t, 1H, J = 7.2 Hz),
7.13 (d,1H, J = 7.8 Hz), 6.50 (s, 1H), 2.51 (s, 3H), 2.32 (s, 3H).
3.7.1.7. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-4-
fluorobenzenesulfonamide (15). 1H NMR (300 MHz, CDCl3-d) d
8.08 (d, 1H, J = 8.4 Hz), 7.89 (m, 3H), 7.58 (t, 1H, J = 8.1 Hz), 7.47
(t, 1H, J = 8.1 Hz), 6.99 (t, 2H, J = 8.4 Hz), 6.54 (s, 1H), 2.52 (s, 3H).
3.6. HPLC purity analysis
Reverse-phase high performance liquid chromatography (RP-
HPLC) was performed on a HPLC Breeze from Waters Inc. (Milford,
3.7.1.8. N-(4-(N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-
yl)sulfamoyl)phenyl)acetamide (16). 1H NMR (300 MHz, CDCl3-
d) d 8.06 (d, 1H, J = 8.1 Hz), 7.89 (d, 1H, J = 7.8 Hz), 7.80 (d, 2H,
J = 8.7 Hz), 7.59–7.40 (m, 4H), 6.49 (s, 1H), 2.50 (s, 3H), 2.16 (s, 3H).
MA) using a Symmetry C18 (5
l
M; 4.6 mm ꢀ 150 mm) reverse
phase column (Waters Inc.). Mobile phase A was 0.1% trifluoroace-
tic acid/H2O and mobile phase B was 0.1% trifluoroacetic acid/ace-
tonitrile in which the flow rate was 1 mL/min for 20 min. A linear
gradient program was used from 50% A and 50% B to 5% A and 95%
B in 15 min followed by 5 min at 100% B. Results were analyzed
using the Breeze software (Waters Inc.).
3.7.1.9. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-4-
nitrobenzenesulfonamide (17). 1H NMR (300 MHz, CDCl3-d) d
8.13 (q, 4H, J = 9.0 Hz), 8.07 (d, 1H, J = 8.1 Hz), 7.91 (d, 1H,
J = 8.1 Hz), 7.61 (dist. t, 1H, J = 8.1 Hz), 7.49 (dist. t, 1H,
J = 8.1 Hz), 6.59 (s, 1H), 2.52 (s, 3H); HRMS (ESI), m/z Calcd for
C18H13N3O4S3 [MꢁH]+ 432.0141. Found 432.0137.
3.7. Synthetic chemistry
3.7.1. General procedure for the synthesis of monosubstituted
benzothiazole sufonylamides
3.7.1.10. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
4-chloro-2-fluorobenzenesulfonamide (18). 1H NMR (300 MHz,
CDCl3-d) d 8.11 (d, 1H, J = 8.4 Hz), 7.92 (d, 1H, J = 7.8 Hz), 7.89 (s,
1H), 7.59 (t, 1H, J = 8.4 Hz), 7.46 (dist. t, 1H, J = 8.4 Hz), 7.20 (d,
1H, J = 9.6 Hz), 7.03 (d, 1H, J = 9.6 Hz), 6.49 (s, 1H), 2.53 (s, 3H).
To a solution of the amine (0.812 mmol) in pyridine (10 mL)
was added the sulfonyl chloride (1.22 mmol) dropwise and the
mixture was stirred at room temperature overnight. The mixture
was diluted with CH2Cl2 (20 mL) and extracted with 3 N HCl (3ꢀ)
and the aqueous portion was extracted with CH2Cl2 once. The or-
ganic layer was dried with Na2SO4 and concentrated. Purification
was done via column chromatography using ethyl acetate and hex-
ane to give the desired compound. Note: In some cases, purifica-
tion had to be done twice.
3.7.1.11. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
3-fluoro-4-methylbenzenesulfonamide (19). 1H NMR (300 MHz,
CDCl3-d) d 8.08 (d, 1H, J = 8.1 Hz), 7.91 (d, 1H, J = 7.8 Hz), 7.60–7.50
(m, 3H), 7.44 (dist. t, 1H, J = 7.2 Hz), 7.15 (dist. t, 1H, J = 7.2 Hz),
6.53 (s, 1H), 2.52 (s, 3H), 2.23 (s, 3H).
3.7.1.1. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl) benzenesul-
3.7.1.12. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
4-fluoro-3-methylbenzenesulfonamide (20). 1H NMR (300 MHz,
CDCl3-d) d 8.08 (d, 1H, J = 8.1 Hz), 7.91 (d, 1H, J = 8.1 Hz), 7.69–7.62
(m, 2H), 7.60 (dist. t, 1H, J = 7.2 Hz), 7.44 (dist. t, 2H, J = 7.2 Hz) 6.92
(t, 1H, J = 9.0 Hz), 6.55 (s, 1H), 2.52 (s, 3H), 2.08 (s, 3H); HRMS (ESI),
m/z Calcd for C19H15FN2O2S3 [MꢁH]+ 419.0352. Found 419.0356.
fonamide (9). 1H NMR (300 MHz, CDCl3-d)
d 8.09 (d, 1H,
J = 8.1 Hz), 7.89 (d, 2H, J = 7.8 Hz), 7.57 (dist. t, 1H, J = 8.1, 7.2 Hz),
7.45 (d, 1H, J = 8.4 Hz), 7.34 (dist. t, 2H, J = 7.8, 7.2 Hz), 6.51 (s,
1H), 2.51 (s, 3H).
3.7.1.2. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-3-
(trifluoromethyl) benzenesulfonamide (10). 1H NMR (300 MHz,
CDCl3-d) d 8.10 (dist. t, 2H, J = 9.3, 2.1 Hz), 8.00 (d, 1H, J = 8.1 Hz),
7.89 (d, 1H, J = 7.8 Hz), 7.69 (d, 1H, J = 7.8 Hz), 7.58 (t, 1H,
J = 8.1 Hz), 7.45 (t, 2H, J = 8.1 Hz), 6.58 (s, 1H), 2.51 (s, 3H).
3.7.1.13. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
3-chloro-4-methylbenzenesulfonamide (21). 1H NMR (300 MHz,
CDCl3-d) d 8.08 (d, 1H, J = 8.4 Hz), 7.90 (d, 1H, J = 7.8 Hz), 7.83 (s,
1H), 7.63–7.54 (m, 2H), 7.43 (dist. t, 1H, J = 8.4 Hz), 7.16 (d, 1H,
J = 7.8 Hz), 6.54 (s, 1H), 2.50 (s, 3H), 2.31 (s, 3H).
3.7.1.3. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-2-
(trifluoromethyl)benzenesulfonamide (11). 1H NMR (300 MHz,
CDCl3-d) d 8.38 (d, 1H, J = 9.0 Hz), 8.08 (d, 1H, J = 8.4 Hz), 7.89 (d,
1H, J = 7.8 Hz), 7.80 (d, 2H, J = 9.0 Hz), 7.66 (dist. t, 1H, J = 3.6 Hz),
3.7.1.14. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
2,4,5-trichlorobenzenesulfonamide (22). 1H NMR (300 MHz,
CDCl3-d) d 8.32 (s, 1H), 8.05 (d, 1H, J = 8.1 Hz), 7.93 (d, 1H,

S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
3363
J = 8.1 Hz), 7.57 (dist. t, 1H, J = 7.5 Hz), 7.48 (s, 1H), 7.31 (dist. t, 1H,
J = 6.99), 6.49 (s, 1H), 2.55 (s, 3H).
3.7.1.25. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
3-methoxybenzenesulfonamide (33). 1H NMR (300 MHz, CDCl3-
d) d 8.07 (d, 1H, J = 8.1 Hz), 7.89 (d, 1H, J = 8.1 Hz), 7.55 (t, 1H,
J = 8.1 Hz), 7.43 (d, 1H, J = 7.8 Hz), 7.34 (s, 1H), 7.22 (t, 1H,
J = 8.1 Hz), 6.95 (d, 1H, J = 8.1 Hz), 6.51 (s, 1H), 3.60 (s, 3H), 2.48 (s,
3H).
3.7.1.15. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
3-chloro-4-fluorobenzenesulfonamide (23). 1H NMR (300 MHz,
CDCl3-d) d 8.09 (d, 1H, J = 8.4 Hz), 7.93 (d, 2H, J = 8.1 Hz), 7.76–7.71
(m, 1H), 7.60 (dist. t, 1H, J = 8.1, 7.5 Hz), 7.46 (dist. t, 1H, J = 7.8,
7.5 Hz), 7.07 (t, 1H, J = 8.4 Hz), 6.59 (s, 1H), 2.53 (s, 3H).
3.7.1.26. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
naphthalene-2-sulfonamide (34). 1H NMR (300 MHz, CDCl3-d) d
8.46 (s, 1H), 8.13 (d, 1H, J = 8.1 Hz), 7.86–7.72 (m, 5H), 7.61–7.50
(m, 3H), 7.43 (dist. t, 1H, J = 7.8 Hz), 7.16 (d, 1H, J = 7.8 Hz), 6.49
(s, 1H), 2.44 (s, 3H).
3.7.1.16. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
3,4-dimethoxybenzenesulfonamide (24). 1H NMR (300 MHz,
CDCl3-d) d 8.08 (d, 1H, J = 8.1 Hz), 7.90 (d, 1H, J = 7.8 Hz), 7.55 (dist.
t, 1H, J = 8.1, 7.2 Hz), 7.46–7.39 (m, 2H), 7.20 (s, 1H), 6.71 (d, 1H,
J = 8.4 Hz), 6.54 (s, 1H), 3.82 (s, 3H), 3.57 (s, 3H), 2.50 (s, 3H).
3.7.1.27. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
biphenyl-4-sulfonamide (35). 1H NMR (300 MHz, CDCl3-d) d
8.11 (d, 1H, J = 8.1 Hz), 7.91–7.87 (m, 3H), 7.59 (dist. t, 1H,
J = 7.2 Hz), 7.59 (m, 8H, J = 6.9 Hz), 6.55 (s, 1H), 2.51 (s, 3H).
3.7.1.17. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
4-tert-butylbenzenesulfonamide (25). 1H NMR (300 MHz,
CDCl3-d) d 8.09 (d, 1H, J = 8.1 Hz), 7.89 (d, 1H, J = 8.1 Hz), 7.74 (d,
2H, J = 8.1 Hz), 7.58 (dist. t, 1H, J = 8.1, 7.2 Hz), 7.44 (dist. t, 1H,
J = 8.1, 7.2 Hz), 7.32 (s, 2H), 6.55 (s, 1H), 2.52 (s, 3H), 1.24 (s, 9H).
3.7.1.28. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
40-methoxybiphenyl-4-sulfonamide (36). 1H NMR (300 MHz,
CDCl3-d) d 8.11 (d, 1H, J = 8.1 Hz), 7.90–7.85 (m, 3H), 7.58 (dist. t,
2H, J = 7.2, 6.9 Hz), 7.49–7.41 (m, 5H), 7.96 (d, 2H, J = 9.0 Hz),
6.54 (s, 1H), 3.86 (s, 3H).
3.7.1.18. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
3,4-dichlorobenzenesulfonamide (26). 1H NMR (300 MHz,
CDCl3-d) d 8.08 (d, 1H, J = 8.1 Hz), 7.94–7.91 (m, 2H), 7.63 (dist. t,
2H, J = 9.0, 8.1 Hz), 7.46 (dist. t, 1H, J = 7.8, 7.2 Hz), 7.37 (d, 1H,
J = 9.0 Hz), 6.59 (s, 1H), 2.53 (s, 3H).
3.7.1.29. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
40-chlorobiphenyl-4-sulfonamide (37). 1H NMR (300 MHz,
CDCl3-d) d 8.11 (d, 1H, J = 7.5 Hz), 7.92–7.86 (m, 3H), 7.57 (d, 1H,
J = 8.7 Hz), 7.49–7.40 (m, 8H), 6.55 (s, 1H), 2.51 (s, 3H).
3.7.1.19. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
3-chloro-2-fluorobenzenesulfonamide (27). 1H NMR (300 MHz,
CDCl3-d) d 8.14 (d, 1H, J = 8.1 Hz), 8.00–7.11 (m, 2H), 7.62–7.52 (m,
2H), 7.46 (dist. t, 1H, J = 8.1, 7.2 Hz), 7.18 (t, 1H, J = 8.1 Hz), 6.49 (s,
1H), 2.54 (s, 3H).
3.7.1.30. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiopen-2-yl)-40-
methoxybiphenyl-3-sulfonamide (38). 1H NMR (300 MHz,
CDCl3-d) d 8.10 (d, 1H, J = 7.8 Hz), 7.98 (s, 1H), 7.87 (d, 1H,
J = 7.2 Hz), 7.76 (d, 1H, J = 7.8 Hz), 7.59 (d, 1H, J = 7.2 Hz), 7.55 (d,
1H, J = 7.2 Hz), 7.42 (t, 1H, J = 8.1 Hz), 7.35 (t, 1H, J = 7.8 Hz), 7.22
(d, 2H, J = 8.7 Hz), 6.82 (d, 1H, J = 8.7 Hz), 6.53 (s, 1H), 3.84 (s,
3H), 2.48 (s, 3H).
3.7.1.20. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
3-chloro-2-methylbenzenesulfonamide (28). 1H NMR (300 MHz,
CDCl3-d) d 8.06 (t, 2H, J = 8.7 Hz), 7.94 (d, 1H, J = 8.1 Hz), 7.59 (dist. t,
1H, J = 8.1, 7.2 Hz), 7.54 (d, 1H, J = 8.1 Hz), 7.46 (dist. t, 1H, J = 8.1,
7.2 Hz), 7.23 (t, 1H, J = 8.1 Hz), 6.44 (s, 1H), 2.76 (s, 3H), 2.54 (s, 3H).
3.7.1.31. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiopen-2-yl)-40-
chlorobiphenyl-3-sulfonamide (39). 1H NMR (300 MHz, CDCl3-
d) d 8.10 (d, 1H, J = 8.1 Hz), 7.95 (s, 1H), 7.88 (d, 1H, J = 8.1 Hz),
7.80 (d, 1H, J = 7.8 Hz), 7.60 (d, 1H, J = 7.0 Hz), 7.56 (d, 1H,
J = 7.0 Hz), 7.50–7.36 (m, 3H), 7.19 (d, 3H, J = 8.1 Hz), 6.57 (s, 1H),
2.50 (s, 3H).
3.7.1.21. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
3-nitrobenzenesulfonamide (29). 1H NMR (300 MHz, CDCl3-d) d
8.43 (s, 1H), 8.09 (d, 1H, J = 8.4 Hz), 7.94–7.89 (m, 2H), 7.59 (dist. t,
1H, J = 8.1, 7.2 Hz), 7.46 (dist. t, 1H, J = 8.1, 7.2 Hz), 7.30 (d, 1H,
J = 8.1 Hz), 6.60 (s, 1H), 2.56 (s, 3H), 2.52 (s, 3H).
3.7.1.32. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiopen-2-yl)-30,50-
bis(trifluoromethyl)biphenyl-3-sulfonamide (40). 1H NMR
(300 MHz, CDCl3-d) d 8.10 (d, 1H, J = 8.1 Hz), 7.96–7.87 (m, 6H), 7.60
(t, 1H, J = 8.1 Hz), 7.52–7.42 (m, 3H), 6.59 (s, 1H), 2.51 (s, 3H).
3.7.1.22. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
4-chloro-3-(trifluoromethyl)benzenesulfonamide (30). 1H NMR
(300 MHz, CDCl3-d) d 8.12 (s, 1H), 8.08 (d, 1H, J = 7.8 Hz), 7.91 (dist.
t, 1H, J = 7.8, 6.9 Hz), 7.60 (dist. t, 1H, J = 8.1, 7.5 Hz), 7.48 (d, 1H,
J = 7.5 Hz), 7.43 (d, 1H, J = 8.1 Hz), 6.61 (s, 1H), 2.53 (s, 3H).
3.7.1.33. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiopen-2-yl)-
biphenyl-3-sulfonamide (41). 1H NMR (300 MHz, CDCl3-d) d
8.10 (d, 1H, J = 8.1 Hz), 8.04 (s, 1H), 7.87 (d, 1H, J = 8.1 Hz), 7.81
(d, 1H, J = 7.8 Hz), 7.64 (d, 1H, J = 8.1 Hz), 7.55 (dist. t, 1H, J = 8.1,
7.2 Hz), 7.45–7.35 (m, 2H), 7.30 (br s, 5H), 6.54 (s, 1H), 2.49 (s, 3H).
3.7.1.23. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
3-chlorobenzenesulfonamide (31). 1H NMR (300 MHz, CDCl3-d)
d 8.08 (d, 1H, J = 8.4 Hz), 7.90 (d, 1H, J = 7.8 Hz), 7.84 (s, 1H), 7.72
(d, 2H, J = 7.8 Hz), 7.58 (dist. t, 1H, J = 8.4, 8.1 Hz), 7.44 (t, 1H,
J = 8.1 Hz), 7.42 (d, 1H, J = 7.8 Hz), 7.28 (d, 1H, J = 8.4), 6.55 (s,
1H), 2.51 (s, 3H).
3.7.1.34. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)benzenesul-
fonamide (43). 1H NMR (300 MHz, CDCl3-d) d 8.04 (d, 1H,
J = 8.1 Hz), 7.94 (d, 2H, J = 7.5 Hz), 7.85 (d, 1H, J = 7.8 Hz), 7.56–
7.38 (m, 5H), 7.09 (d, 1H, J = 5.7 Hz), 6.83 (d, 2H, J = 5.7).
3.7.1.24. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-
3-(trifluoromethoxy)benzenesulfonamide (32). 1H NMR (300
MHz, CDCl3-d) d 8.07 (d, 1H, J = 8.4 Hz), 7.89 (d, 1H, J = 8.1 Hz),
7.77 (d, 1H, J = 7.8 Hz), 7.71 (s, 1H), 7.58 (dist. t, 1H, J = 8.1,
7.2 Hz), 7.44 (dist. t, 1H, J = 8.1, 7.2 Hz), 7.36–7.22 (m, 1H), 6.57 (s,
1H), 2.51 (s, 3H).
3.7.1.35. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-3-(trifluoro-
methyl)benzenesulfonamide (44). 1H NMR (300 MHz, CDCl3-d)
d 8.18 (s, 1H), 8.06 (dist. t, 2H, J = 7.8 Hz), 7.87 (d, 1H, J = 7.8 Hz),
7.72 (d, 1H, J = 7.8 Hz), 7.59–7.42 (m, 4H), 7.12 (d, 1H, J = 5.7 Hz),
6.91 (d, 2H, J = 5.7 Hz).

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S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
3.7.1.36. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-2-(trifluoro-
methyl)benzenesulfonamide (45). 1H NMR (300 MHz, CDCl3-d)
d 8.36 (dd, 1H, J = 4.8, 2.7 Hz), 8.05 (d, 1H, J = 8.1 Hz), 7.85 (t, 2H,
J = 7.5 Hz), 7.87–7.81 (m, 2H), 7.52 (t, 1H, J = 8.1 Hz), 7.42 (t, 2H,
J = 8.1 Hz), 7.12 (d, 1H, J = 5.7 Hz), 6.81 (d, 1H, J = 5.7 Hz).
1H, J = 8.1 Hz), 7.55 (t, 1H, J = 7.8 Hz), 7.42 (t, 1H, J = 7.8 Hz), 7.21
(d, 1H, J = 8.1 Hz), 7.13 (d, 1H, J = 6.0 Hz), 6.87 (d, 1H, J = 6.0 Hz),
2.33 (s, 3H).
3.7.1.47. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-2,5-bis(2,2,2-
trifluoroethoxy)benzenesulfonamide (56). 1H NMR (300 MHz,
CDCl3-d) d 8.04 (d, 1H, J = 8.1 Hz), 7.88 (d, 1H, J = 8.1 Hz), 7.66 (d, 1H,
J = 3.0 Hz), 7.54 (dist. t, 1H, J = 8.4, 7.2 Hz), 7.41 (dist. t, 2H J = 8.1,
7.2 Hz), 7.15 (d, 1H, J = 3.0 Hz), 7.13 (d, 1H, J = 6.0 Hz), 6.99 (d, 1H,
J = 8.4 Hz), 6.77 (d, 1H, J = 6.0 Hz), 4.46–4.33 (m, 4H).
3.7.1.37. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-(trifluoro-
methoxy)benzenesulfonamide (46). 1H NMR (300 MHz, CDCl3-
d) d 8.04 (dd, 1H, J = 8.7, 2.7 Hz), 7.96 (d, 2H, J = 8.7 Hz), 7.88 (d,
1H, J = 7.8 Hz), 7.57 (dist. t, 1H, J = 8.1, 7.5 Hz), 7.42 (dist. t, 1H,
J = 7.8, 7.5 Hz), 7.18 (d, 2H, J = 7.8 Hz), 7.13 (d, 1H, J = 5.7 Hz),
6.88 (d, 1H, J = 5.7 Hz).
3.7.1.48. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-3-chloro-4-
fluorobenzenesulfonamide (57). 1H NMR (300 MHz, CDCl3-d) d
8.05 (d, 1H, J = 8.7 Hz), 8.00 (d, 1H, J = 7.0 Hz), 7.88 (d, 1H,
J = 8.1 Hz), 7.81–7.76 (m, 1H), 7.56 (dist. t, 1H, J = 8.1, 7.0 Hz),
7.42 (dist. t, 1H, J = 8.1, 7.0 Hz), 7.13 (d, 1H, J = 5.7 Hz), 7.11 (br s,
1H), 6.90 (d, 1H, J = 5.7 Hz).
3.7.1.38. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-methoxy-
benzenesulfonamide (47). 1H NMR (300 MHz, CDCl3-d) d 8.04 (d,
1H, J = 8.1 Hz), 7.88–7.83 (m, 3H), 7.54 (t, 1H, J = 8.1 Hz), 7.40 (t, 1H,
J = 8.1 Hz), 7.01 (d, 1H, J = 5.7 Hz), 6.85–6.80 (m, 3H), 3.77 (s, 3H).
3.7.1.39. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-methylben-
zenesulfonamide (48). 1H NMR (300 MHz, CDCl3-d) d 8.04 (d, 1H,
J = 8.1 Hz), 7.86 (d, 1H, J = 7.8 Hz), 7.82 (d, 2H, J = 8.7 Hz), 7.54 (dist.
t, 1H, J = 8.7, 8.1 Hz), 7.41 (dist. t, 1H, J = 8.4, 7.8 Hz), 7.16 (d, 2H,
J = 8.7 Hz), 7.09 (d, 1H, J = 5.7 Hz), 6.82 (d, 1H, J = 5.7 Hz), 2.32 (s,
3H).
3.7.1.49. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-3,4-dimeth-
oxybenzenesulfonamide (58). 1H NMR (300 MHz, CDCl3-d) d
8.03 (d, 1H, J = 7.8 Hz), 7.85 (d, 1H, J = 7.8 Hz), 7.55–7.49 (m,
2H), 7.39 (t, 1H, J = 8.1 Hz), 7.29 (s, 1H), 7.08 (d, 1H, J = 6.0 Hz),
6.85 (d, 1H, J = 6.0 Hz), 6.75 (d, 1H, J = 8.7 Hz), 3.82 (s, 3H), 3.64
(s, 3H).
3.7.1.40. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-fluoroben-
zenesulfonamide (49). 1H NMR (300 MHz, CDCl3-d) d 8.04 (d, 1H,
J = 8.1 Hz), 7.96–7.91 (m, 2H), 7.88 (d, 1H, J = 8.1 Hz), 7.55 (t, 1H,
J = 8.4 Hz), 7.42 (t, 1H, J = 8.4 Hz), 7.12 (d, 1H, J = 6.0 Hz), 7.04 (t,
2H, J = 8.7 Hz), 6.86 (d, 1H, J = 6.0 Hz).
3.7.1.50. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-tert-butyl-
benzenesulfonamide (59). 1H NMR (300 MHz, CDCl3-d) d 8.06 (d,
1H, J = 8.1 Hz), 7.87 (d, 1H, J = 8.4 Hz), 7.82 (d, 1H, J = 8.4 Hz), 7.56
(dist. t, 1H, J = 8.4, 7.2 Hz), 7.43 (d, 1H, J = 7.2 Hz), 7.37 (d, 1H,
J = 8.4 Hz), 7.13 (d, 1H, J = 6.0 Hz), 6.87 (d, 1H, J = 6.0 Hz), 1.25 (s, 9H).
3.7.1.41. N-(4-(3-(benzo[d]thiazol-2-yl)thiopen-2-yl)sulfamoyl)-
phenyl)acetamide (50). 1H NMR (300 MHz, CDCl3-d) d 7.99 (d,
1H, J = 8.1 Hz), 7.82 (d, 1H, J = 7.5 Hz), 7.56–7.48 (m, 3H), 7.38 (dist.
t, 1H, J = 8.1, 7.5 Hz), 7.06 (d, 1H, J = 5.7 Hz), 6.79 (d, 1H, J = 5.7 Hz),
2.13 (s, 3H).
3.7.1.51. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-3,4-dichloro-
benzenesulfonamide (60). 1H NMR (300 MHz, CDCl3-d) d 8.06 (d,
1H, J = 8.1 Hz), 8.00 (s, 1H), 7.89 (d, 1H, J = 8.1 Hz), 7.71 (d, 1H,
J = 8.4 Hz), 7.57 (dist. t, 1H, J = 7.8, 7.5 Hz), 7.44 (dist. t, 1H,
J = 8.1, 6.0 Hz), 7.15 (d, 1H, J = 5.7 Hz), 6.91 (d, 1H, J = 5.7 Hz).
3.7.1.42. N-(3-(Benzo[d] N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-
yl)-4-(trifluoromethyl)benzenesulfonamide (51). 1H NMR (300
MHz, CDCl3-d) d 8.04 (m, 3H), 7.88 (d, 1H, J = 7.8 Hz), 7.64–7.53
(m, 3H), 7.43 (dist. t, 1H, J = 7.8, 7.2 Hz), 7.13 (d, 2H, J = 5.4 Hz),
6.89 (d, 1H, J = 5.4 Hz).
3.7.1.52. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-3-chloro-2-
fluorobenzenesulfonamide (61). 1H NMR (300 MHz, CDCl3-d) d
8.11 (d, 1H, J = 8.0 Hz), 7.89 (d, 1H, J = 6.0 Hz), 7.57 (t, 1H,
J = 7.0 Hz), 7.44 (t, 1H, J = 7.0 Hz), 7.21 (d, 1H, J = 8.0 Hz), 7.15 (d,
1H, J = 5.7 Hz), 6.84 (d, 1H, J = 5.7 Hz).
3.7.1.43. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-chloro-2-
fluorobenzenesulfonamide (52). 1H NMR (300 MHz, CDCl3-d) d
8.08 (d, 1H, J = 8.1 Hz), 7.96–7.88 (m, 2H), 7.56 (dist. t, 1H, J = 8.4,
6.9 Hz), 7.44 (dist. t, 1H, J = 8.4, 6.9 Hz), 7.23 (d, 1H, J = 8.4 Hz),
7.14 (d, 1H, J = 5.7 Hz), 7.08 (d, 1H, J = 9.0 Hz), 6.83 (d, 1H,
J = 5.7 Hz).
3.7.1.53. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-3-chloro-2-
methylbenzenesulfonamide (62). 1H NMR (300 MHz, CDCl3-d) d
8.07 (d, 1H, J = 8.1 Hz), 8.02 (d, 1H, J = 8.4 Hz), 7.90 (d, 1H,
J = 8.1 Hz), 7.56 (dist. t, 1H, J = 8.1, 7.2 Hz), 7.43 (dist. t, 1H,
J = 7.8, 7.2 Hz), 7.24 (t, 1H, J = 8.1 Hz), 7.13 (d, 1H, J = 5.7 Hz), 6.78
(d, 1H, J = 5.7 Hz), 2.81 (s, 3H).
3.7.1.44. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-3-fluoro-4-
methylbenzenesulfonamide (53). 1H NMR (300 MHz, CDCl3-d) d
8.05 (d, 1H, J = 8.1 Hz), 7.87 (d, 1H, J = 8.1 Hz), 7.62–7.52 (m, 2H),
7.42 (t, 1H, J = 8.1 Hz), 7.20 (t, 1H, J = 7.5 Hz), 7.13 (d, 1H,
J = 5.4 Hz), 6.86 (d, 1H, J = 5.4 Hz), 2.24 (s, 3H).
3.7.1.54. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-methyl-3-
nitrobenzenesulfonamide (63). 1H NMR (300 MHz, CDCl3-d) d
8.51 (s, 1H), 8.04 (d, 1H, J = 8.1 Hz), 7.97 (d, 1H, J = 8.1 Hz), 7.86
(d, 1H, J = 7.8 Hz), 7.55 (t, 1H, J = 7.8 Hz), 7.42 (t, 1H, J = 7.8 Hz),
7.33 (d, 1H, J = 8.1 Hz), 7.12 (d, 1H, J = 5.7 Hz), 6.91 (d, 1H,
J = 5.7 Hz), 2.55 (s, 3H).
3.7.1.45. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-fluoro-3-
methylbenzenesulfonamide (54). 1H NMR (300 MHz, CDCl3-d) d
8.05 (d, 1H, J = 8.1 Hz), 7.87 (d, 1H, J = 8.1 Hz), 7.76 (dist. t, 1H,
J = 7.8, 7.0 Hz), 7.72–7.69 (m, 1H), 7.68– 7.52 (m, 1H), 7.41 (dist.
t, 1H, J = 8.1, 7.0 Hz), 7.11 (d, 1H, J = 5.7 Hz), 7.00–6.88 (m, 1H),
6.86 (d, 1H, J = 5.7 Hz), 2.13 (s, 3H).
3.7.1.55. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-chloro-3-
(trifluoromethyl)benzenesulfonamide (64). 1H NMR (300 MHz,
CDCl3-d) d 8.22 (s, 1H), 8.05 (d, 1H, J = 8.1 Hz), 7.97 (d, 1H,
J = 8.4 Hz), 7.89 (d, 1H, J = 8.1 Hz), 7.58 (dist. t, 1H, J = 8.1, 7.2 Hz),
7.51–7.42 (m, 2H), 7.15 (d, 1H, J = 6.0 Hz), 6.94 (d, 1H, J = 6.0 Hz).
3.7.1.46. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-3-chloro-4-
methylbenzenesulfonamide (55). 1H NMR (300 MHz, CDCl3-d) d
8.05 (d, 1H, J = 8.1 Hz), 7.90 (s, 1H), 7.87 (d, 1H, J = 8.1 Hz), 7.67 (d,
3.7.1.56. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-chloroben-
zenesulfonamide (65). 1H NMR (300 MHz, CDCl3-d) d 8.05 (d, 1H,
J = 7.5 Hz), 7.90–7.82 (m, 3H), 7.55 (t, 1H, J = 7.2 Hz), 7.44 (t, 1H

S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
3365
J = 7.5 Hz), 7.40–7.31 (m, 2H), 7.12 (d, 1H, J = 6.3 Hz), 6.86 (d, 1H,
J = 6.3 Hz).
8.05 (d, 1H, J = 7.8 Hz), 7.84 (d, 2H, J = 7.8 Hz), 7.65 (d, 1H,
J = 7.8 Hz), 7.52 (dist. t, 1H, J = 8.1, 7.2 Hz), 7.44–7.38 (m, 3H),
7.30 (br s, 4H), 7.09 (d, 1H, J = 6.0 Hz), 6.85 (d, 1H, J = 6.0 Hz).
3.7.1.57. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-6-chloronaph-
thalene-2-sulfonamide (66). 1H NMR (300 MHz, CDCl3-d) d 8.47
(s, 1H), 8.08 (d, 1H, J = 8.4 Hz), 7.89–7.67 (m, 5H), 7.56 (dist. t, 1H,
J = 8.1, 7.2), 7.50–7.39 (m, 2H), 7.07 (d, 1H, J = 5.7 Hz), 6.82 (d, 1H,
J = 5.7 Hz).
3.7.1.68. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-40-(trifluo-
romethyl)biphenyl-4-sulfonamide (77). 1H NMR (300 MHz,
CDCl3-d) d 8.04 (d, 1H, J = 8.1 Hz), 7.98 (d, 2H, J = 8.1 Hz), 7.83
(d, 1H, J = 8.1 Hz), 7.66 (d, 2H, J = 8.4 Hz), 7.57–7.52 (m, 5H),
7.40 (dist. t, 3H, J = 7.8 Hz), 7.10 (d, 1H, J = 5.7 Hz), 6.86 (d, 1H,
J = 5.7 Hz).
3.7.1.58. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-6-chloronaph-
thalene-2-sulfonamide (67). 1H NMR (300 MHz, CDCl3-d) d 8.47
(s, 1H), 8.08 (d, 1H, J = 8.4 Hz), 7.89–7.67 (m, 5H), 7.56 (dist. t, 1H,
J = 8.1, 7.2), 7.50–7.39 (m, 2H), 7.07 (d, 1H, J = 5.7 Hz), 6.82 (d, 1H,
J = 5.7 Hz).
3.7.1.69. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-30,40-dime-
thoxybiphenyl-4-sulfonamide (78). 1H NMR (300 MHz, CDCl3-d)
d 8.06 (d, 1H, J = 8.4 Hz), 7.94 (d, 2H, J = 8.4 Hz), 7.84 (d, 1H,
J = 8.1 Hz), 7.04 (d, 1H, J = 8.1 Hz), 6.98 (s, 1H), 6.90 (d, 1H,
J = 8.4 Hz), 6.84 (d, 1H, J = 6.0 Hz), 3.92 (s, 3H).
3.7.1.59. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-chloro-3-
(trifluoromethyl)benzenesulfonamide (68). 1H NMR (300 MHz,
CDCl3-d) d 8.04 (d, 1H, J = 8.7 Hz), 7.90 (d, 1H, J = 7.8 Hz), 7.77 (d,
1H, J = 9.0 Hz), 7.56 (dist. t, 1H, J = 7.8, 7.5 Hz), 7.50 (d, 2H,
J = 9.0 Hz), 7.44 (dist. t, 1H, J = 8.7, 8.1 Hz), 7.13 (d, 1H, J = 5.7 Hz),
6.88 (d, 1H, J = 5.7 Hz).
3.7.1.70. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-(2-chloro-
phenoxy)benzenesulfonamide (79). 1H NMR (300 MHz, CDCl3-
d) d 8.00 (d, 1H, J = 8.1 Hz), 7.88 (d, 3H, J = 8.7 Hz), 7.67 (d, 1H,
J = 5.7 Hz), 7.55–7.39 (m, 2H), 7.24 (d, 2H, J = 7.5 Hz), 7.05–6.95
(m, 3H), 6.90 (d, 1H, J = 7.8 Hz), 6.79 (d, 1H, J = 8.7 Hz), 3.77 (s, 3H).
3.7.1.60. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-40-methylbi-
phenyl-4-sulfonamide (69). 1H NMR (300 MHz, CDCl3-d) d 8.07
(d, 1H, J = 8.1 Hz), 7.95 (d, 1H, J = 8.1 Hz), 7.92 (d, 2H, J = 8.1 Hz),
7.85 (d, 2H, J = 8.1 Hz), 7.54 (d, 1H, J = 8.7 Hz), 7.50–7.20 (m, 7H),
7.10 (d, 1H, J = 5.7 Hz), 6.85 (d, 1H, J = 5.7 Hz).
3.7.1.71. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-(2-methoxy-
phenoxy)benzenesulfonamide (80). 1H NMR (300 MHz, CDCl3-
d) d 8.00 (d, 1H, J = 8.1 Hz), 7.88 (d, 3H, J = 8.7 Hz), 7.67 (d, 1H,
J = 5.7 Hz), 7.55–7.39 (m, 2H), 7.24 (d, 2H, J = 7.5 Hz), 7.05–6.95
(m, 3H), 6.90 (d, 1H, J = 7.8 Hz), 6.79 (d, 1H, J = 8.7 Hz), 3.77 (s, 3H).
3.7.1.61. N-(3-(Benzo[d]thiazol-2-yl)isoxazol-5-yl)-40-methoxy-
biphenyl-4-sulfonamide (70). 1H NMR (300 MHz, CDCl3-d) d
8.27 (s, 1H), 8.00 (d, 2H, J = 8.4 Hz), 7.97–7.89 (m, 2H), 7.72 (d,
2H, J = 7.0 Hz), 7.58 (d, 2H, J = 7.0 Hz), 7.49 (t, 1H, J = 7.0 Hz), 7.40
(d, 1H, J = 8.4 Hz), 7.04 (d, 1H, J = 7.5 Hz), 3.90 (s, 3H).
3.7.1.72. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-6-phenoxy-
pyridine-3-sulfonamide (81). 1H NMR (300 MHz, CDCl3-d) d 8.70
(d, 1H, J = 2.7 Hz), 8.24 (dd, 1H, J = 8.7, 2.7 Hz), 7.90 (dist. t, 2H,
J = 9.0, 8.1 Hz), 7.60–7.40 (m, 6H), 7.32–7.28 (m, 1H), 7.02 (d, 2H,
J = 8.7 Hz), 6.83 (d, 1H, J = 9.0 Hz).
3.7.1.62. N-(3-(Benzo[d]thiazol-2-yl)isoxazol-5-yl)-40-chlorobi-
phenyl-4-sulfonamide (71). 1H NMR (300 MHz, CDCl3-d) d 8.22
(s, 1H), 8.02 (d, 1H, J = 8.1 Hz), 7.94–7.86 (m, 2H), 7.71 (d, 1H,
J = 8.4 Hz), 7.57–7.40 (m, 5H), 7.37 (d, 2H, J = 7.8 Hz).
3.7.1.73. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-4-(thiazol-
5-yl)benzenesulfonamide (82). 1H NMR (300 MHz, CDCl3-d) d
8.04 (d, 1H, J = 8.1 Hz), 7.85 (d, 1H, J = 8.1 Hz), 7.65 (d, 2H,
J = 8.4 Hz), 7.57 (dist. t, 1H, J = 7.2, 6.3 Hz), 7.45–7.29 (m, 2H),
7.12 (d, 1H, J = 6.0 Hz), 6.89 (d, 1H, J = 6.0 Hz), 2.64 (s, 3H).
3.7.1.63. N-(3-(Benzo[d]thiazol-2-yl)isoxazol-5-yl)-40-trifluoro-
methoxybiphenyl-4-sulfonamide (72). 1H NMR (300 MHz,
CDCl3-d) d 8.06 (d, 2H, J = 7.8 Hz), 7.96 (d, 2H, J = 8.4 Hz), 7.85 (d,
1H, J = 7.8 Hz), 7.60–7.38 (m, 6H), 7.26 (d, 2H, J = 7.8 Hz), 7.11 (d,
1H, J = 6.0 Hz), 6.88 (d, 1H, J = 6.0 Hz).
3.7.1.74. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-4-(oxazol-5-
yl)benzenesulfonamide (83). 1H NMR (300 MHz, CDCl3-d) d 8.07
(d, 1H, J = 8.1 Hz), 7.96 (d, 1H, J = 8.1 Hz), 7.94 (s, 1H), 7.85 (d, 1H,
J = 8.1 Hz), 7.60 (d, 2H, J = 8.4 Hz), 7.56 (dist. t, 1H, J = 8.4, 8.1 Hz),
7.41 (t, 1H, J = 8.1 Hz), 7.40 (s, 1H), 7.26 (d, 1H, J = 2.1 Hz), 7.11 (d,
1H, J = 5.7 Hz), 6.86 (d, 1H, J = 5.7 Hz).
3.7.1.64. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-40-methoxy-
biphenyl-3-sulfonamide (73). 1H NMR (300 MHz, CDCl3-d) d
8.04 (br s, 2H), 7.85 (d, 2H, J = 8.1 Hz), 7.80 (d, 1H, J = 8.1 Hz),
7.62 (d, 1H, J = 7.2 Hz), 7.52 (dist. t, 1H, J = 8.1, 7.2 Hz), 7.43–7.35
(m, 3H), 7.09 (d, 1H, J = 6.0 Hz), 6.85 (d, 1H, J = 6.0 Hz), 6.80 (d,
1H, J = 8.7 Hz), 3.82 (s, 3H).
3.7.1.75. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-3-(5-methyl-
1,3,4-oxadiazol-2-yl)benzenesulfonamide (84). 1H NMR (300
MHz, CDCl3-d) d 8.50 (s, 1H), 8.18 (d, 1H, J = 8.1 Hz), 8.08 (d, 1H,
J = 8.1 Hz), 8.01 (d, 1H, J = 7.8 Hz), 7.57–7.38 (m, 3H), 7.12 (d, 1H,
J = 6.0 Hz), 6.90 (d, 1H, J = 6.0 Hz).
3.7.1.65. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-40-chlorobi-
phenyl-3-sulfonamide (74). 1H NMR (300 MHz, CDCl3-d) d 8.04
(br s, 2H), 7.84 (d, 3H, J = 8.1 Hz), 7.60–7.40 (m, 4H), 7.27–7.21
(m, 3H), 7.09 (d, 1H, J = 5.7 Hz), 6.86 (d, 1H, J = 5.7 Hz).
3.7.1.76. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-4-(1H-pyra-
zol-1-yl)benzenesulfonamide (85). 1H NMR (300 MHz, CDCl3-d)
d 8.07 (d, 1H, J = 8.1 Hz), 7.99 (d, 2H, J = 9.0 Hz), 7.89 (d, 1H,
J = 2.0 Hz), 7.86 (d, 1H, J = 8.1 Hz), 7.71 (d, 3H, J = 9.0 Hz), 7.53 (t,
1H, J = 7.8 Hz), 7.41 (t, 1H, J = 7.8 Hz), 7.11 (d, 1H, J = 5.4 Hz), 6.87
(d, 1H, J = 5.4 Hz), 6.48 (t, 1H, J = 2.0 Hz).
3.7.1.66. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-30,40-dichlo-
robiphenyl-4-sulfonamide (75). 1H NMR (300 MHz, CDCl3-d) d
8.07 (d, 1H, J = 7.8 Hz), 7.96 (d, 2H, J = 8.4 Hz), 7.86 (d, 1H,
J = 9.0 Hz), 7.60–7.40 (m, 6H), 7.32–7.31 (m, 1H), 7.13 (d, 1H,
J = 5.7 Hz), 6.89 (d, 1H, J = 5.7 Hz).
3.7.1.77. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-5-methyl-1-
phenyl-1H-pyrazole-4-sulfonamide (86). 1H NMR (300 MHz,
CDCl3-d) d 8.01 (d, 1H, J = 7.8 Hz), 7.92 (s, 1H), 7.90 (d, 1H,
J = 8.1 Hz), 7.53 (dist. t, 1H, J = 8.1, 7.5 Hz), 7.43 (d, 1H, J = 3.9 Hz),
3.7.1.67. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)biphenyl-3-
sulfonamide (76). 1H NMR (300 MHz, CDCl3-d) d 8.09 (br s, 1H),

3366
S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
7.42 (br s, 4H), 7.22 (d, 1H, J = 3.9 Hz), 7.19 (d, 1H, J = 5.7 Hz), 6.91
(d, 1H, J = 5.7 Hz), 2.48 (s, 3H).
3.7.1.87. N-(3-(Benzo[d] N-(3-(Benzo[d]thiazol-2-yl)thiophen-
2-yl)-3-methylbenzo[b]thiophene-2-sulfonamide (96). 1H NMR
(300 MHz, CDCl3-d)
d 8.04 (d, 1H, J = 8.1 Hz), 7.85 (d, 1H,
J = 8.1 Hz), 7.66–7.54 (m, 4H), 7.45–7.35 (m, 2H), 7.13 (d, 1H,
J = 6.0 Hz), 6.89 (d, 1H, J = 6.0 Hz), 2.65 (s, 3H).
3.7.1.78. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-4-(morphol-
inosulfonyl)benzenesulfonamide (87). 1H NMR (300 MHz,
CDCl3-d) d 8.04 (d, 3H, J = 8.7 Hz), 7.89 (d, 1H, J = 8.4 Hz), 7.70 (d,
1H, J = 8.4 Hz), 7.57 (dist. t, 1H, J = 8.4, 7.2 Hz), 7.44 (dist. t, 1H,
J = 8.1, 7.2 Hz), 7.15 (d, 1H, J = 6.0 Hz), 6.94 (d, 1H, J = 6.0 Hz),
3.68 (t, 4H, J = 4.5 Hz), 2.85 (t, 4H, J = 4.5 Hz).
3.7.1.88. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-5-(isoxazol-
5-yl)thiophene-2-sulfonamide (97). 1H NMR (300 MHz, CDCl3-
d) d 8.25 (s, 1H), 8.05 (d, 1H, J = 7.8 Hz), 7.62 (d, 1H, J = 3.9 Hz),
7.55 (dist. t, 1H, J = 7.8, 7.0 Hz), 7.41 (dist. t, 1H, J = 7.8, 7.0 Hz),
7.30 (d, 1H, J = 3.9 Hz), 7.18 (d, 1H, J = 5.7 Hz), 6.94 (d, 1H,
J = 5.7 Hz), 6.40 (s, 1H).
3.7.1.79. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-3-(2-meth-
ylpyrimidine-4-yl)benzenesulfonamide (88). 1H NMR (300 MHz,
CDCl3-d) d 8.54 (s, 2H), 8.22 (d, 1H, J = 7.8 Hz), 8.07 (d, 1H, J = 8.1 Hz),
7.98 (d, 1H, J = 7.8 Hz), 7.84 (d, 1H, J = 8.1 Hz), 7.55–7.48(m, 2H), 7.42
(dist. t, 1H, J = 7.8, 7.2 Hz), 7.25 (d, 1H, J = 5.4 Hz), 7.09 (d, 1H,
J = 5.4 Hz), 6.88 (d, 1H, J = 5.7 Hz), 2.72 (s, 3H).
3.7.1.89. N-((5-(N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)sulfa-
moyl)thiophen-2-yl)methyl)-4-chlorobenzamide (98). 1H NMR
(300 MHz, CDCl3-d)
d 8.02 (d, 1H, J = 7.5 Hz), 7.85 (d, 1H,
J = 7.8 Hz), 7.78 (d, 1H, J = 9.0 Hz), 7.65 (d, 2H, J = 9.0 Hz), 7.55 (t,
2H, J = 8.4 Hz), 7.45–29 (m, 3H), 7.16 (d, 1H, J = 6.0 Hz), 6.90 (d,
1H, J = 6.0 Hz), 4.68 (d, 1H, J = 5.7 Hz).
3.7.1.80. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-(3,5-dimeth-
yl-1H-pyrazol-1-yl)benzenesulfonamide (89). 1H NMR (300 MHz,
CDCl3-d) d 8.04–7.96 (m, 3H), 7.83 (d, 1H, J = 8.1 Hz), 7.54–7.44 (m,
3H), 7.38 (t, 1H, J = 8.0 Hz), 7.08 (d, 1H, J = 6.0 Hz), 6.82 (d, 1H,
J = 6.0 Hz), 5.97 (s, 1H), 2.26 (s, 3H), 2.22 (s, 3H).
3.7.1.90. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-5-(2-(meth-
ylthio)pyrimidin-4-yl)thiophene-2-sulfonamide (99). 1H NMR
(300 MHz, CDCl3-d)
d 8.50 (d, 1H, J = 5.1 Hz), 8.07 (d, 1H,
3.7.1.81. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-3-dihydro-
benzofuran-5-sulfonamide (90). 1H NMR (300 MHz, CDCl3-d) d
8.05 (d, 1H, J = 7.8 Hz), 7.87 (d, 1H, J = 8.1 Hz), 7.71 (s, 1H), 7.68
(d, 1H, J = 8.4 Hz), 7.54 (dist. t, 1H, J = 8.4, 6.9 Hz), 7.41 (dist. t,
1H, J = 7.8, 6.9 Hz), 7.11 (d, 1H, J = 6.0 Hz), 6.85 (d, 1H, J = 6.0 Hz),
6.68 (d, 1H, J = 8.1 Hz).
J = 7.8 Hz), 7.86 (d, 1H, J = 8.1 Hz), 7.64 (d, 2H, J = 3.9 Hz), 7.55 (t,
1H, J = 8.4 Hz), 7.52 (d, 1H, J = 3.9 Hz), 7.41 (dist. t, 1H, J = 7.8,
7.2 Hz), 7.18 (d, 1H, J = 5.7 Hz), 7.12 (d, 1H, J = 5.1 Hz), 6.95 (d,
1H, J = 5.7 Hz), 2.53 (s, 3H).
3.7.1.91. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)furan-2-sul-
fonamide (100). 1H NMR (300 MHz, d-DMSO) d 8.13 (br s, 1H),
7.89 (br s, 1H), 7.73 (br s, 1H), 7.30 (br s, 1H), 7.17 (d, 1H,
J = 8.4 Hz), 7.13 (s, 1H), 6.96 (br s, 1H, J = 6.0 Hz), 6.76 (dist. t, 2H,
J = 8.4, 8.1 Hz), 6.63 (br s, 1H).
3.7.1.82. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)benzo[c][1,2,5]-
oxadiazole-5-sulfonamide (91). 1H NMR (300 MHz, CDCl3-d) d
8.24 (d, 1H, J = 7.8 Hz), 8.13 (d, 1H, J = 7.0 Hz), 8.01 (d, 1H,
J = 9.0 Hz), 7.83 (d, 2H, J = 8.1 Hz), 7.63 (dist. t, 1H, J = 8.1,
6.9 Hz), 7.52–7.41 (m, 3H), 7.06 (d, 1H, J = 5.7 Hz), 6.81 (d, 1H,
J = 5.7 Hz).
3.7.1.92. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-1-(methyl-
sulfonyl)methanesulfonamide (101). 1H NMR (300 MHz, CDCl3-
d) d 8.02 (d, 1H, J = 8.1 Hz), 7.84 (d, 1H, J = 7.8 Hz), 7.58 (dist. t, 1H,
J = 8.1, 7.5 Hz), 7.46 (dist. t, 1H, J = 8.1, 7.5 Hz), 7.04 (d, 1H,
J = 6.3 Hz), 6.73 (d, 1H, J = 6.3 Hz), 4.63 (s, 2H), 3.41 (s, 3H).
3.7.1.83. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)benzo[d]thi-
azole-6-sulfonamide (92). 1H NMR (300 MHz, CDCl3-d) d 9.14 (s,
1H), 8.60 (s, 1H), 8.10–8.00 (m, 3H), 7.85 (d, 1H, J = 8.1 Hz), 7.57 (t,
1H, J = 8.1 Hz), 7.42 (d, 1H, J = 8.1 Hz), 7.10 (d, 1H, J = 6.0 Hz), 6.87
(d, 1H, J = 6.0 Hz).
3.7.1.93. N-(3-(Benzo[d]thiazol-2-yl)thiopen-2-yl)-4-bromo-3-
chlorobenzenesulfonamide (123). 1H NMR (300 MHz, CDCl3-d) d
8.05 (d, 1H, J = 8.1 Hz), 7.98 (t, 1H, J = 1.2 Hz), 7.89 (d, 1H,
J = 8.1 Hz), 7.60 (br s, 2H), 7.56 (dist. t, 1H, J = 8.7, 8.1 Hz), 7.44 (t,
1H, J = 8.1 Hz), 7.15 (d, 1H, J = 5.7 Hz), 6.10 (d, 1H, J = 5.7 Hz).
3.7.1.84. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-2,3-dihydro-
benzo[b][1,4]dioxine-6-sulfonamide (93). 1H NMR (300 MHz,
CDCl3-d) d 8.04 (d, 1H, J = 8.1 Hz), 7.86 (d, 1H, J = 7.8 Hz), 7.54 (t,
1H, J = 7.2 Hz), 7.46 (d, 1H, J = 2.1 Hz), 7.40 (dist. t, 1H, J = 8.1,
6.0 Hz), 7.11 (d, 1H, J = 6.0 Hz), 6.84 (d, 1H, J = 6.0 Hz), 6.81 (d,
1H, J = 8.1 Hz), 4.40–4.00 (m, 4H).
3.7.1.94. N-(Benzo[d]thiazol-2-yl)-3-chloro-4-methylbenzene-
sulfonamide (102). 1H NMR (300 MHz, CDCl3-d) d 7.96 (s, 1H),
7.77 (dist. t, 2H, J = 7.8 Hz), 7.59 (d, 1H, J = 7.8 Hz), 7.44 (dist. t,
1H, J = 7.5 Hz), 7.35–7.30 (m, 2H), 2.43 (s, 3H).
3.7.1.85. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-4-methyl-
3,4-dihydro-2H-pyrido[3,2-b][1,4]oxazine-7-sulfonamide
(94). 1H NMR (300 MHz, CDCl3-d) d 8.30 (d, 1H, J = 2.1 Hz), 8.04 (d,
1H, J = 8.1 Hz), 7.85 (d, 1H, J = 7.8 Hz), 7.53 (dist. t, 1H, J = 8.1,
7.2 Hz), 7.39 (dist. t, 1H, J = 7.8, 7.2 Hz), 7.26 (d, 1H, J = 2.1 Hz),
7.11 (d, 1H, J = 6.0 Hz), 6.82 (d, 1H, J = 6.0 Hz), 4.11 (t, 2H,
J = 4.5 Hz), 3.45 (t, 4H, J = 4.5 Hz), 3.13 (s, 3H).
3.7.1.95. N-(Benzo[d]thiazol-2-yl)-40-methoxybiphenyl-4-sulfon-
amide (103). 1H NMR (300 MHz, DMSO-d)
d 7.90 (d, 2H,
J = 8.4 Hz), 7.83–7.79 (m, 3H), 7.67 (d, 2H, J = 8.7 Hz), 7.46–7.20
(m, 5H), 7.05 (d, 1H, J = 8.7 Hz), 3.81 (s, 3H).
3.7.1.96. N-(Benzo[d]thiazol-2-yl)-40-chlorobiphenyl-4-sulfon-
amide (104). 1H NMR (300 MHz, DMSO-d) d 7.95–7.73 (m, 8H),
7.56 (d, 1H, J = 8.4 Hz), 7.40–7.30 (m, 2H), 7.23 (t, 1H, J = 6.6 Hz).
3.7.1.86. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-4-methyl-
3,4-dihydro-2H-benzo[b][1,4]oxazine-7-sulfonamide (95). 1H
NMR (300 MHz, CDCl3-d) d 8.04 (d, 1H, J = 8.1 Hz), 7.87 (d, 1H,
J = 8.1 Hz), 7.52 (t, 1H, J = 8.1 Hz), 7.39 (dist. t, 1H, J = 8.1, 7.2 Hz),
7.19 (dd, 1H, J = 8.4, 2.1 Hz), 7.11 (d, 1H, J = 6.0 Hz), 7.09 (d, 1H,
J = 2.1 Hz), 6.84 (d, 1H, J = 6.0 Hz), 6.66 (d, 1H, J = 8.4 Hz), 4.23 (t,
2H, J = 4.0), 3.17 (t, 2H, J = 4.0).
3.7.1.97. N-(3-Benzo[d]thiazol-2-yl)-4,5,6,7-tetrahydrobenzo[b]-
thiophen-2-yl)-40-methoxybiphenyl-4-sulfonamide (105). 1H
NMR (300 MHz, CDCl3-d) d 8.08 (d, 1H, J = 8.1 Hz), 7.90–7.83 (m,
3H), 7.57 (t, 2H, J = 8.0 Hz), 7.47–7.38 (m, 5H), 6.96 (d, 2H,

S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
3367
J = 6.0 Hz), 3.85 (s, 3H), 2.81 (br s, 1H), 2.72 (br s, 1H), 1.88 (br s,
4H).
(d, 1H, J = 3.6 Hz), 7.35 (s, 1H), 7.26 (d, 2H, J = 3.6 Hz), 7.07 (t, 1H,
J = 4.2 Hz), 6.91 (br s, 1H), 2.46 (s, 3H).
3.7.1.98. N-(3-Benzo[d]thiazol-2-yl)-4,5,6,7-tetrahydrobenzo[b]-
thiophen-2-yl)-40-chlorobiphenyl-4-sulfonamide (106). 1H NMR
(300 MHz, CDCl3-d) d 8.08 (d, 1H, J = 8.4 Hz), 7.93–7.84 (m, 3H),
7.57 (t, 1H, J = 8.1 Hz), 7.50–7.44 (m, 3H), 7.40 (s, 4H), 2.83 (br s,
1H), 2.73 (br s, 1H), 1.88 (br s, 4H).
3.7.1.109. N-(4-Methyl-3-(trifluoromethyl)phenyl)thiophene-2-
sulfonamide (117). 1H NMR (300 MHz, CDCl3-d) d 7.61 (d, 1H,
J = 4.2 Hz), 7.54 (d, 1H, J = 3.6 Hz), 7.35 (s, 1H), 7.26 (d, 2H,
J = 3.6 Hz), 7.07 (t, 1H, J = 4.2 Hz), 6.91 (br s, 1H), 2.46 (s, 3H).
3.7.1.110. N-(3-Trifluoromethyl)phenyl)thiophene-2-sulfonamide
(118). 1H NMR (300 MHz, CDCl3-d) d 7.62–7.57 (m, 2H), 7.45–7.38
(m, 4H), 7.16 (br s, 1H), 7.06 (t, 1H, J = 3.9 Hz).
3.7.1.99. N-(3-(Benzo[d]thiazol-2-yl)isoxazol-5-yl)-40-methoxy-
biphenyl-4-sulfonamide (107). 1H NMR (300 MHz, CDCl3-d) d
8.27 (s, 1H), 8.00 (d, 2H, J = 8.4 Hz), 7.97–7.89 (m, 2H), 7.72 (d,
2H, J = 7.0 Hz), 7.58 (d, 2H, J = 7.0 Hz), 7.49 (t, 1H, J = 7.0 Hz), 7.40
(d, 1H, J = 8.4 Hz), 7.04 (d, 1H, J = 7.5 Hz), 3.90 (s, 3H).
3.7.1.111. N-Phenylthiophene-2-sulfonamide (119). 1H NMR
(300 MHz, CDCl3-d) d 7.55 (t, 2H, J = 5.7 Hz), 7.31 (dist. t, 2H,
J = 8.1 Hz), 7.19 (dist. t, 3H, J = 8.1 Hz), 7.08 (br s, 1H), 7.03 (q,
1H, J = 3.9, 1.2 Hz).
3.7.1.100. N-(3-(Benzo[d]thiazol-2-yl)isoxazol-5-yl)-40-chloro-
biphenyl-4-sulfonamide (108). 1H NMR (300 MHz, CDCl3-d) d
8.22 (s, 1H), 8.02 (d, 1H, J = 8.1 Hz), 7.94–7.86 (m, 2H), 7.71 (d,
1H, J = 8.4 Hz), 7.57–7.40 (m, 5H), 7.37 (d, 2H, J = 7.8 Hz).
3.7.2. General procedure for the synthesis of disubstituted ben-
zothiazole sufonylamides
To a solution of the amine (0.812 mmol) and the sulfonyl chlo-
ride (1.60 mmol) in dichloromethane (10 mL) was added triethyl-
amine (29.23 mmol) dropwise and the mixture was stirred at
room temperature overnight. The mixture was diluted with CH2Cl2
(20 mL) and extracted with 3 N HCl (3ꢀ) and the aqueous portion
was extracted with CH2Cl2 once. The organic layer was dried with
Na2SO4 and concentrated. Purification was done via flash column
chromatography using ethyl acetate and hexane to give the desired
compound.
3.7.1.101. N-(2-(Benzo[d]thiazol-2-yl)ethyll)-40-methoxybiphenyl-
4-sulfonamide (109). 1H NMR (300 MHz, CDCl3-d) d 7.92–7.86
(m, 3H), 7.72 (d, 1H, J = 8.1 Hz), 7.64 (d, 2H, J = 8.7 Hz), 7.53 (d,
2H, J= 8.7 Hz), 7.50 (d, 1H, J = 7.8 Hz), 7.38 (t, 1H, J = 7.8 Hz), 7.10
(dist. t, 2H, J = 9.0, 7.8 Hz), 6.99 (d, 1H, J = 9.0 Hz), 3.86 (s, 3H),
2.79 (t, 2H, J = 7.0 Hz), 2.40 (t, 2H, J = 7.0 Hz).
3.7.1.102. N-(2-(Benzo[d]thiazol-2-yl)ethyll)-40-chlorobiphenyl-
4-sulfonamide (110). 1H NMR (300 MHz, CDCl3-d) d 7.93 (d, 2H,
J = 8.1 Hz), 7.87 (br s, 1H), 7.71 (d, 1H, J = 8.4 Hz), 7.65 (d, 2H,
J = 8.1 Hz), 7.53–7.35 (m, 6H), 7.10 (t, 1H, J = 7.8 Hz), 2.82 (t, 2H,
J = 7.0 Hz), 2.42 (t, 2H, J = 7.0 Hz).
3.7.2.1. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-3-
(trifluoromethyl)-N-(3-(trifluoromethyl)phenylsulfonyl)benzene-
sulfonamide (120). 1H NMR (300 MHz, CDCl3-d) d 8.31 (s, 2H),
8.11 (d, 2H, J = 7.8 Hz), 7.92 (d, 1H, J = 8.1 Hz), 7.75 (d, 1H,
J = 8.1 Hz), 7.59 (d, 2H, J = 7.8 Hz), 7.49 (dist. t, 1H, J = 8.1, 7.2),
7.41 (dist. t, 1H, J = 8.1, 7.2 Hz), 7.34 (t, 2H, J = 7.8 Hz), 7.25 (s,
1H), 2.46 (s, 3H).
3.7.1.103. N-(2-(Benzo[d]thiazol-2-yl)phenyl)-40-methoxybiphe-
nyl-4-sulfonamide (111). 1H NMR (300 MHz, CDCl3-d) d 8.15 (d,
1H, J = 8.1 Hz), 7.86 (dist. t, 2H, J = 7.2, 6.9 Hz), 7.78 (d, 2H, J=
8.4 Hz), 7.72 (d, 1H, J = 7.8 Hz), 7.58 (dist. t, 1H, J = 8.1, 7.2 Hz),
7.46 (dist. t, 2H, J = 8.4, 8.1 Hz), 7.43–7.37 (m, 4H), 7.15 (t, 1H,
J = 7.8 Hz), 6.95 (d, 2H, J = 6.9 Hz), 3.84 (s, 3H).
3.7.2.2. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-4-
(trifluoromethoxy)-N-(4-(trifluoromethoxy)phenylsulfonyl)ben-
zenesulfonamide (121). 1H NMR (300 MHz, CDCl3-d) d 8.01 (m,
5H), 7.77 (d, 1H, J = 7.8 Hz), 7.54 (dist. t, 1H, J = 8.1, 7.2 Hz), 7.42
(t, 1H, J = 8.1 Hz), 7.19 (s, 1H), 7.05 (d, 4H, J = 8.1 Hz), 2.46 (s,
3H).
3.7.1.104. N-(2-(Benzo[d]thiazol-2-yl)phenyl)-40-chlorobiphenyl-
4-sulfonamide (112). 1H NMR (300 MHz, CDCl3-d) d 8.15 (d, 1H,
J = 8.1 Hz), 7.87 (t, 2H, J = 9.0 Hz), 7.80 (d, 2H, J= 8.1 Hz), 7.74 (d,
1H, J = 8.1 Hz), 7.60 (dist. t, 1H, J = 7.8, 7.5 Hz), 7.47 (dist. t, 2H,
J = 8.4, 8.1 Hz), 7.42–7.38 (m, 6H), 7.12 (dist. t, 1H, J = 7.8,
7.5 Hz).
3.7.2.3. N-(3-(Benzo[d]thiazol-2-yl)-4-methylthiophen-2-yl)-4-
fluoro-N-(4-fluorophenylsulfonyl)benzenesulfonamide (122). 1H
NMR (300 MHz, CDCl3-d) d 8.03 (d, 1H, J = 8.1 Hz), 7.97 (dd, 4H,
J = 9.3, 5.1 Hz), 7.80 (d, 1H, J = 8.1 Hz), 7.55 (t, 1H, J = 8.1 Hz),
7.44 (t, 1H, J = 8.1 Hz), 7.18 (s, 1H), 6.91 (t, 4H, J = 9.3 Hz), 2.41
(s, 3H).
3.7.1.105. 3-Chloro-4-methyl-N-(thiophen-2-yl)benzenesulfon-
amide (113). 1H NMR (300 MHz, CDCl3-d)
d 7.79 (d, 1H,
J = 2.0 Hz), 7.57 (dd, 1H, J = 8.1, 2.0 Hz), 7.34 (d, 1H, J = 8.1 Hz),
7.05 (dd, 1H, J = 5.1, 1.2 Hz), 6.86–6.82 (m, 1H), 6.74 (dd, 1H,
J = 5.1, 2.0 Hz), 2.45(s, 3H).
3.7.3. General procedure for Suzuki coupling conditions31
A solution of bromobenzothiazole derivative (0.206 mmol),
Pd(PPh3)4 (0.0206 mmol), boric acid derivative (0.247 mmol), EtOH
(0.5 mL) and Na2CO3 (2 M, 2 mL) in toluene (10 mL) was refluxed
for 18 h. The reaction mixture was filtered and concentrated. The
residue was dissolved in dichloromethane and extracted with
water, brine and dried with Na2SO4. Purification was done via flash
column chromatography using ethyl acetate and hexane (1:2) to
give the desired compound.
3.7.1.106. 40-Methoxy-N-(thiophen-2-yl)biphenyl-4-sulfonamide
(114). 1H NMR (300 MHz, CDCl3-d) d 7.82 (d, 2H, J = 9.0 Hz), 7.67
(d, 2H, J = 8.7 Hz), 7.58 (d, 2H, J = 9.0 Hz), 7.04 (dist. t, 3H, J = 9.0,
8.7 Hz), 6.86 (dist. t, 1H, J = 5.7, 3.6 Hz), 6.77 (d, 1H, J = 3.6 Hz),
6.56 (br s, 1H), 3.89 (s, 3H).
3.7.1.107. 40-Chloro-N-(thiophen-2-yl)biphenyl-4-sulfonamide
(115). 1H NMR (300 MHz, CDCl3-d) d 7.93 (d, 2H, J = 8.4 Hz), 7.84
(d, 2H, J = 8.1 Hz), 7.79 (d, 2H, J = 8.1 Hz), 7.74 (d, 1H, J = 8.7 Hz),
7.56 (d, 2H, J = 8.4 Hz), 7.40–7.30 (m, 2H), 7.23 (t, 1H, J = 6.6 Hz).
3.7.3.1. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-40-(trifluoro-
methoxy)biphenyl-4-sulfonamide (72). 1H NMR (300 MHz,
CDCl3-d) d 8.05 (d, 1H, J = 7.8 Hz), 7.96 (d, 2H, J = 8.4 Hz), 7.85 (d,
1H, J = 7.8 Hz), 7.60–7.38 (m, 6H), 7.40 (d, 2H, J = 7.8 Hz), 7.11 (d,
1H, J = 6.0 Hz), 6.87 (d, 1H, J = 6.0 Hz).
3.7.1.108. N-(3-Chloro-4-methylphenyl)thiophene-2-sulfonamide
(116). 1H NMR (300 MHz, CDCl3-d) d 7.61 (d, 1H, J = 4.2 Hz), 7.54

3368
S. L. Johnson et al. / Bioorg. Med. Chem. 17 (2009) 3352–3368
3.7.3.2. N-(3-(Benzo[d]thiazol-2-yl)thiophen-2-yl)-2-chloro-40-
methoxybiphenyl-4-sulfonamide (124). 1H NMR (300 MHz,
CDCl3-d) d 8.07 (d, 1H, J = 8.1 Hz), 8.00 (s, 1H), 7.87 (d, 2H,
J = 8.1 Hz), 7.77 (d, 1H, J = 8.1 Hz), 7.55 (t, 1H, J = 8.1 Hz), 7.42 (t,
1H, J = 8.1 Hz), 7.31–7.23 (m, 3H), 7.15 (d, 1H, J = 6.0 Hz), 6.96–
6.90 (m, 3H), 6.81 (s, 1H), 3.86 (s, 3H).
A. M.; Douglas, C. M.; Patel, S. B.; Wisniewski, D.; Scapin, G.; Salowe, S. P.;
Zaller, D. M.; Chapman, K. T.; Scolnick, E. M.; Schmatz, D. M.; Bartizal, K.;
MacCoss, M.; Hermes, J. D. Proc. Natl. Acad. Sci. U.S.A. 2005, 102, 7958.
14. Johnson, S. L.; Chen, L. H.; Pellecchia, M. Bioorg. Chem. 2007, 35, 306.
15. Numa, M. M.; Lee, L. V.; Hsu, C. C.; Bower, K. E.; Wong, C. H. Chembiochem 2005,
6, 1002.
16. Verma, R. P.; Hansch, C. Mol. Pharm. 2008, 5, 745.
17. Forino, M.; Johnson, S.; Wong, T. Y.; Rozanov, D. V.; Savinov, A. Y.; Li, W.;
Fattorusso, R.; Becattini, B.; Orry, A. J.; Jung, D.; Abagyan, R. A.; Smith, J. W.;
Alibek, K.; Liddington, R. C.; Strongin, A. Y.; Pellecchia, M. Proc. Natl. Acad. Sci.
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Acknowledgement
18. Johnson, S. L.; Jung, D.; Forino, M.; Chen, Y.; Satterthwait, A.; Rozanov, D. V.;
Strongin, A. Y.; Pellecchia, M. J. Med. Chem. 2006, 49, 27.
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Strongin, A.; Guiney, D.; Pellecchia, M. Chem. Biol. Drug Des. 2008, 71, 131.
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This work was supported in part by NIH grants 1UO1 AI056385
and 1R01 AI059572
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