3-(Arylacetylamino)-N-methylbenzamides: A novel class of selective anti-Helicobacter pylori agents

Article abstract of DOI:10.1021/jm010307o

After chemical modification preceded by the random screening of our chemical library, a novel class of selective anti-Helicobacter pylori agents was generated. Consequently, the 3-(arylacetylamino)-N-methylbenzamides, which were quite easy to prepare, showed potent inhibitory activity against Helicobacter pylori but exhibited no inhibitory activity against other sorts of bacteria and fungi, e.g., Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Bacteroides fragilis, and Candida albicans. These compounds showed potent anti-H. pylori activity under acidic conditions, whereas amoxicillin and clarithromycin decreased activity. The 3-(3-arylpropionylamino)-N-methylbenzamides, 3-(aryloxyacetylamino)-N-methylbenzamides, and (3-methylcarbamoylphenyl)carbamic acid 1-arylmethyl esters also exhibited potent anti-H. pylori activity. Finally, we selected 7n (BAS-118) as a candidate compound for further evaluation.

Full text of DOI:10.1021/jm010307o

4468
J . Med. Chem. 2001, 44, 4468-4474
3-(Ar yla cetyla m in o)-N-m eth ylben za m id es: A Novel Cla ss of Selective
An ti-Helicoba cter pylor i Agen ts
Ryoichi Ando,*,† Makoto Kawamura,† and Noriko Chiba‡
Research Laboratory, Pharmaceuticals Research Division, Mitsubishi Pharma Corporation, 1000 Kamoshida-cho,
Aoba-ku, Yokohama 227-0033, J apan, and Life Science Laboratory, Science and Technology Research Center,
Mitsubishi Chemical Corporation, 1000 Kamoshida-cho, Aoba-ku, Yokohama, 227-8502, J apan
Received J uly 3, 2001
After chemical modification preceded by the random screening of our chemical library, a novel
class of selective anti-Helicobacter pylori agents was generated. Consequently, the 3-(aryl-
acetylamino)-N-methylbenzamides, which were quite easy to prepare, showed potent inhibitory
activity against Helicobacter pylori but exhibited no inhibitory activity against other sorts of
bacteria and fungi, e.g., Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas
aeruginosa, Bacteroides fragilis, and Candida albicans. These compounds showed potent anti-
H. pylori activity under acidic conditions, whereas amoxicillin and clarithromycin decreased
activity. The 3-(3-arylpropionylamino)-N-methylbenzamides, 3-(aryloxyacetylamino)-N-meth-
ylbenzamides, and (3-methylcarbamoylphenyl)carbamic acid 1-arylmethyl esters also exhibited
potent anti-H. pylori activity. Finally, we selected 7n (BAS-118) as a candidate compound for
further evaluation.
In tr od u ction
Helicobacter pylori (H. pylori) is a Gram-negative
microaerophilic bacterium which was isolated and iden-
tified first in the stomach of patients with gastritis and
peptic ulcer.1 Further investigations revealed that the
F igu r e 1. Hit compound from random screening.
bacterium is an important cause of gastritis, is respon-
sible for the formation and recurrence of gastric and
duodenal ulcers, and is closely related with gastric
cancer.2 Besides gastroduodenal disease, associations
between H. pylori infection and other various extra-
intestinal pathologies have been reported.3
In the clinical setting, H. pylori is eradicated mainly
by triple therapy which consists of a combination of two
antibacterial agents with different mechanisms of ac-
tion, which are selected from amoxicillin, clarithromy-
cin, and metronidazole, and in a proton pump inhibitor.
However, antibacterial agents used in this therapy show
a broad and potent antibacterial spectrum; high dose
and long-term administration are required for complete
eradication. This therapy thus occasionally provokes
side effects such as diarrhea, including pseudomembra-
nous enterocolitis in serious cases. Therefore, the de-
velopment of selective anti-H. pylori agents is demanded
to avoid such drawbacks.
F igu r e 2. Regioisomers of compound 1.
activity on dihydroorotate dehydrogenase, H. pylori-
selective pyrazole derivatives have been reported re-
cently.13
To generate a new class of selective anti-H. pylori
agents, we randomly screened our original chemical
library. The selectivity for the other bacteria, e.g.,
Staphylococcus aureus, Bacillus subtilis, Escherichia
coli, Pseudomonas aeruginosa, Bacteroides fragilis, and
Candida albicans, was investigated in some selected
compounds. These investigations afforded several new
classes of H. pylori-selective compounds. Among them,
compound 1 (Figure 1) was most attractive because
of its simple structure, synthetic easiness, stability
under acidic conditions,14 potent anti-H. pylori activity
(MIC ) 0.39 µg/mL), and excellent selectivity for other
bacteria and fungi. We report herein the synthesis of
derivatives of compound 1 and their structure-activity
relationship.
As selective anti-H. pylori agents, omeprazole and its
sulfide derivative,4 2-(substituted guanidino)-4-(furyl or
phenyl)thiazoles,5 benzyloxyisoquinoline derivatives,6
and FR1457157 have been reported. Some natural
products, e.g., phthalide compounds,8 alkylquinolone
derivatives,9,10 cabreuvin,11 and γ-pyrone compounds,12
also have shown potent activity against and good
selectivity for H. pylori. On the basis of their inhibitory
Ch em istr y
Derivatives of the N-methylbenzamide moiety
(4a -g) were prepared as described in Scheme 1a. (3-
Bromophenyl)acetic acid 2 was treated with oxalyl
chloride and a catalytic amount of DMF in CH2Cl2 to
* To whom correspondence should be addressed. Tel: +81-45-
963-3352.
Fax:
+81-45-963-3977.
E-mail:
Ando.Ryoichi@
mk.m-pharm.co.jp.
† Mitsubishi Pharma Corporation.
‡ Mitsubishi Chemical Corporation.
10.1021/jm010307o CCC: $20.00 © 2001 American Chemical Society
Published on Web 11/10/2001

Novel Class of Selective Anti-H. pylori Agents
J ournal of Medicinal Chemistry, 2001, Vol. 44, No. 25 4469
Sch em e 1. Synthesis of Amide Derivatives
Ta ble 1. SAR of Benzamide Moiety
Sch em e 2. Synthesis of Carbamate Derivatives
no.
X
MIC (µg/mL)
1
CONHCH3
COOCH2CH3
COOH
0.39
>100
>100
100
4a
4b
4c
4d
4e
4f
4g
CONH2
CON(CH3)2
CONHCH2CH3
CONHOH
CONHOCH3
clarithromycin
25
3.12
12.5
12.5
0.05
Ta ble 2. SAR of Phenylacetamide Moiety
no.
R3
MIC (µg/mL)
7a
7b
7c
7d
7e
1
7f
7g
7h
7i
Ph
3-F-Ph
2-Cl-Ph
3-Cl-Ph
4-Cl-Ph
3-Br-Ph
4-Br-Ph
3-Me-Ph
3-MeO-Ph
3-PhCH2O-Ph
3-NO2-Ph
3-OH-Ph
1.56
3.12
3.12
0.39
0.78
0.39
0.78
0.39
0.78
0.78
3.12
6.25
afford the corresponding acid chloride, which was al-
lowed to react with 3-aminobenzoic acid ethyl ester 3
in the presence of pyridine to give the coupled product
4a . The ester moiety in 4a was then hydrolyzed, and
the carboxylic acid obtained was converted to acid
chloride, which was treated with amine derivatives to
afford the amide derivatives 4c-g. The o- and p-
derivatives (12 and 13 (Figure 2), respectively) were also
prepared in a similar manner. The N-methylbenzamide
derivative 7 was obtained in one step (Scheme 1b).
Therefore, coupling of the arylacetic acid 5 with the
commercially available 3-amino-N-methylbenzamide 6
via acid chloride yielded the desired product effica-
ciously.15
The method for the preparation of the carbamate
derivative 11 is shown in Scheme 2. Treatment of the
alcohol derivative 8 and di(N-succinimidyl) carbonate
9 in the presence of triethylamine in CH2Cl2 afforded
the active ester 10, which was allowed to react with the
aniline derivative 6 to afford the carbamate derivative
11.
7j
7k
also showed less potent activity. The benzoic acid
derivative 4b and its ethyl ester 4a were not active.
Alternatively, we also prepared the o- and p-substituted
N-methylbenzamide derivatives (12 and 13, respec-
tively) which did not show any anti-H. pylori activity
(MIC > 50 µg/mL). Accordingly, only the m-substituted
N-methylbenzamide derivative 1 was shown to have
potent anti-H. pylori activity.
Second, the effects of substituents on the phenyl ring
in the phenylacetamide moiety were investigated (Table
2). Regarding the position of substituents, the anti-H.
pylori activity of the 2-chloro compound 7c was less
potent; hence, the 3- and 4-chloro compounds (7d and
7e, respectively) showed similar potent activity. Regard-
ing the bromo-substituted compounds, the 3-and 4-sub-
stituted compounds (1 and 7f, respectively) also showed
similar anti-H. pylori activity. Therefore, the effects of
substituents are represented here by the results of the
3-substituted derivatives.16 Small substituents, e.g.,
hydrogen (7a ) and fluorine (7b), showed less potent anti-
H. pylori activity. Among large substituents, the lipo-
Resu lts a n d Discu ssion
First, transformation of the N-methylbenzamide moi-
ety was examined, the results of which are summarized
in Table 1. The N-methyl derivative 1 showed potent
anti-H. Pylori activity, while the N-ethyl derivative 4e
showed less potent activity. The unsubstituted benz-
amide derivative 4c and the N,N-dimethyl derivative
4d showed much less activity. Other amide derivatives,
e.g., the hydroxamic acid 4f and its O-methyl ester 4g,

4470 J ournal of Medicinal Chemistry, 2001, Vol. 44, No. 25
Ta ble 3. SAR of Arylacetamide and Other Amide Derivatives
Ando et al.
Ta ble 5. Anti-H. pylori Activity under Acidic Conditions
no.
R3
MIC (µg/mL)
MIC (µg/mL)
7l
cyclohexyl
1-naphthyl
2-naphthyl
3-benzothienyl
3,4-methylendioxyphenyl
3-indolyl
benzyl
2-MeO-benzyl
phenoxy
12.5
0.10
0.05
0.10
0.78
0.78
12.5
0.78
3.12
0.39
0.10
0.39
compound
pH 7.0
pH 6.0
pH 5.0
7m
7n
7o
7p
7q
7r
7s
7t
7u
7v
7w
amoxicillin
clarithromycin
7m
7n
7o
0.031
0.063
0.125
0.063
0.25
0.125
0.50
0.125
0.063
0.25
0.50
2.0
0.125
0.063
0.25
moiety were widely acceptable; especially, the lipophilic
flat structure afforded quite potent anti-H. pylori activ-
ity.
2,3-Cl2-phenoxy
1-naphthoxy
2-naphthoxy
Selectivity for Staphylococcus aureus, Bacillus sub-
tilis, Escherichia coli, Pseudomonas aeruginosa, Bactero-
ides fragilis, and Candida albicans was evaluated by
the agar hole method to several active compounds. None
of the tested compounds (1, 4e-g, 7a -h , 7m , and 7n )
showed antibacterial and antifungal activity against any
of the tested organisms at a concentration of 1000 µg/
mL. Although the inhibition mechanism against H.
pylori remains unknown at present, the potent inhibi-
tory activity against and complete selectivity for H.
pylori of the above mentioned compounds are quite
important points for a drug with fewer side effects.
Finally, anti-H. pylori activity under acidic conditions
was evaluated.17 Activity of amoxicillin and clarithro-
mycin at pH 5.0 was 16-32 times less potent than that
at pH 7.0, whereas MIC values of compounds 7m , 7n ,
and 7o did not change under acidic conditions (Table
5). These results suggest that the above mentioned
compounds would show potent anti-H. pylori activity in
stomach.
Ta ble 4. SAR of Carbamate Derivatives
no.
R4
MIC (µg/mL)
11a
11b
11c
11d
11e
4-Me-Ph
4-Cl-Ph
2,6-Cl2-Ph
1-naphthyl
2-naphthyl
0.10
0.20
0.20
0.05
0.10
philic substituents, e.g., methyl (7g) and methoxy (7h ),
exhibited good activity; however, the activity of polar
substituents, e.g., nitro (7j), and hydrophilic substitu-
ents, e.g., hydroxyl (7k ), was less potent. A very large
and lipophilic benzyloxy group (7i) also showed potent
activity.
Other aromatic rings were also investigated (Table
3). The 1-naphthyl and 2-naphthylacetamide derivatives
(7m and 7n , respectively) showed quite potent anti-H.
pylori activity which was comparable to that of clarithro-
mycin (see Table 1). Among heteroaryl rings, the lipo-
philic rings, e.g., benzothiophene (7o), afforded similar
potency; however, more hydrophilic rings, e.g., the 3,4-
methylenedioxyphenyl and indolyl derivatives (7p and
7q, respectively), exhibited less potent activity. Never-
theless, the cyclohexylacetamide derivative 7l showed
very much less potent activity despite its lipophilic
property. This result indicates that the flat structure
would be essential for potent anti-H pylori activity in
this area.
The 3-phenylpropionylamide derivatives were also
prepared (Table 3). Although the phenyl derivative 7r
showed less potent activity, introduction of the lipophilic
methoxy group at its 2-position (7s) improved activity.
In the case of aryloxyacetamide derivatives (7t-w ),
more lipophilic compounds showed potent anti-H. pylori
activity. Among them, the 1-naphthoxyacetamide de-
rivative 7v afforded quite potent anti-H. pylori activity.
In consideration of the structure-activity relationship
(SAR) of the amide derivatives that introduction of
lipophilic substituents increased activity, the carbamate
derivatives were prepared and some of active com-
pounds are summarized in Table 4. In the case of the
benzyl carbamate derivatives, compounds bearing lipo-
philic substituents, e.g., methyl and chlorine, exhibited
potent anti-H. pylori activity (11a -c). In this case, the
1-naphthylmethyl and 2-naphthylmethyl derivatives
(11d and 11e, respectively) showed quite potent anti-
H. pylori activity, too.
Con clu sion s
After chemical modification preceded by the random
screening of our chemical library, a novel class of
selective anti-Helicobacter pylori agents was generated.
Consequently, the 3-(arylacetylamino)-N-methylbenz-
amides, which were quite easy to prepare, showed
potent inhibitory activity against H. pylori but showed
no inhibitory activity against other sorts of bacteria and
fungi, e.g., Staphylococcus aureus, Bacillus subtilis,
Escherichia coli, Pseudomonas aeruginosa, Bacteroides
fragilis, and Candida albicans. These compounds showed
potent anti-H. pylori activity under acidic conditions,
whereas amoxicillin and clarithromycin decreased activ-
ity. Finally, we selected 7n as a candidate compound
for further evaluation. Details on the microbiological
features of 7n (BAS-118) will be reported soon.
Exp er im en ta l Section
Gen er a l. All 1H NMR spectra taken at 300 MHz were
measured on a Bruker ARX-300 or DPX-300 instrument and
are reported in parts per million from internal tetramethyl-
silane. IR spectra were recorded on a J ASCO FT/IR-5300
instrument; absorptions are reported in cm-1. Most of reagents
were purchased from Tokyo Chemical Industry and were used
without further purification. A clinically isolated Helicobacter
pylori strain 31A was kindly provided from Microorganism
Department, First Laboratory of Bacteria, Tokyo Metropolitan
Research Laboratory of Public Health. Regarding other bac-
teria and fungi, the following standard strains were used:
Bacillus subtilis ATCC6633, Staphylococcus aureus 209P
ATCC6538P, Escherichia coli MCI2195, Pseudomonas aerugi-
nosa MCI2197, Bacteroides fragilis MCI2173, and Candida
albicans MCI2202. Brain-heart infusion and yeast extract
SARs described so far are summarized as follows.
Regarding the methylamide moiety, only the m-substi-
tuted methylamide compound showed potent activity.
On the contrary, substituents of the arylalkylamide

Novel Class of Selective Anti-H. pylori Agents
J ournal of Medicinal Chemistry, 2001, Vol. 44, No. 25 4471
1
were purchased from Difco Laboratories. Fetal bovine serum,
Neutrient agar, and potato dextrose agar were purchased from
Upstate Biotechnology, Eiken, and Nissui, respectively.
1595, 1560; H NMR (DMSO-d6) 3.69 (s, 5 H), 7.22-7.60 (m,
6 H), 7.77 (s, 1 H), 8.00 (s, 1 H), 10.37 (s, 1 H), 11.69 (s, 1 H).
Anal. (C16H15BrN2O3) C, H, N, Br.
2-[2-(3-Br om op h e n yl)a ce t yla m in o]-N -m e t h ylb e n z-
a m id e (12): mp 134 °C; IR (KBr) 3339, 1674, 1651, 1589,
1524; 1H NMR (DMSO-d6) 2.75 (d, J ) 4.5 Hz, 2 H), 3.71 (s, 2
H), 7.11 (dd, J ) 7.5 Hz, 7.5 Hz, 1 H), 7.20-7.35 (m, 2H), 7.40-
7.55 (m, 2H), 7.54 (m, 1H), 7.65 (d, J ) 8.1 Hz, 1H), 8.30 (d,
J ) 8.4 Hz, 1 H), 8.65 (d, J ) 4.5 Hz, 1 H), 11.34 (s, 1H). Anal.
(C16H15BrN2O2) C, H, N, Br.
3-[2-(3-Br om op h en yl)a cetyla m in o]ben zoic Acid Eth yl
Ester (4a ). To a solution of (3-bromophenyl)acetic acid 2 (2.88
g, 13.4 mmol) in CH2Cl2 (30 mL) were added oxalyl chloride
(1.79 g, 14.1 mmol) and two drops of DMF, and the resulting
solution was stirred for 1 h at room temperature. The solution
was then cooled to 0 °C, and 3-aminobenzoic acid ethyl ester
3 (2.21 g, 13.4 mmol) and pyridine (2.70 mL, 33.5 mmol) were
added. After the mixture was stirred at room temperature
overnight, the solvent was removed and water (50 mL) was
added to the residue. The resulting mixture was acidified by
the addition of 2 N HCl, and the precipitates formed were
collected by filtration and were then washed with water. After
drying in vacuo, AcOEt (20 mL) was added to the precipitates;
the mixture was dissolved under reflux conditions. Hexane (10
mL) was then added at that temperature, and the mixture was
cooled to room temperature. The crystals formed were filtered
and were then washed with the solvent (50% AcOEt in hexane)
to afford the titled compound (3.57 g, yield 74%): mp 140 °C;
IR (KBr) 3279, 1713, 1671, 1593, 1557; 1H NMR (CDCl3) 1.38
(t, J ) 4.2 Hz, 3 H), 3.72 (s, 2 H), 4.36 (d, J ) 4.2 Hz, 2 H),
7.10-7.55 (m, 6 H), 7.79 (d, J ) 8.7 Hz, 1 H), 7.85-7.95 (m, 2
H). Anal. (C17H16BrNO3) C, H, N.
4-[2-(3-Br om op h e n yl)a ce t yla m in o]-N -m e t h ylb e n z-
a m id e (13): mp 245 °C; IR (KBr) 3260, 1669, 1634, 1599,
1
1570, 1537, 1507; H NMR (DMSO-d6) 2.73 (d, J ) 4.5 Hz, 3
H), 3.67 (s, 2 H), 7.20-7.35 (m, 2H), 7.44 (m, 1 H), 7.53 (m, 1
H), 7.62 (d, J ) 8.4 Hz, 2 H), 7.76 (d, J ) 8.4 Hz, 2 H), 8.30 (d,
J ) 4.5 Hz, 1 H), 10.38 (s, 1H). Anal. (C16H15BrN2O2) C, H, N,
Br.
3-[2-(3-Ch lor op h e n yl)a ce t yla m in o]-N -m e t h ylb e n z-
a m id e (7d ). (3-Chlorophenyl)acetic acid (192 mg, 1.13 mmol)
was dissolved in CH2Cl2 (8 mL), and oxalyl chloride (0.10 mL,
1.18 mmol) and one drop of DMF were added to the solution.
After the mixture was stirred for 1 h at room temperature,
3-amino-N-methylbenzamide 6 (167 mg, 1.13 mmol) and
pyridine (0.19 mL, 2.31 mmol) were added, and the resulting
solution was then stirred at room temperature overnight.
Subsequently, the solvent was evaporated under reduced
pressure; water (10 mL) and 2 N HCl (1 mL) were added to
the residue. The crystals formed were filtered and were then
washed with water. After drying in vacuo, these crystals were
added to AcOEt (6 mL). Subsequently, the mixture was heated
under reflux for 10 min. The mixture was cooled to room
temperature, and the crystals were collected by filtration and
were then washed with AcOEt to give the desired compound
(233 mg, yield 68%): mp 165-166 °C; IR (KBr) 3324, 1642,
1593, 1555; 1H NMR (DMSO-d6) 2.76 (d, J ) 4.5 Hz, 3 H),
3.68 (s, 2 H), 7.25-7.42 (m, 5 H), 7.48 (d, J ) 7.8 Hz, 1 H),
7.74 (d, J ) 7.8 Hz, 1 H), 8.02 (dd, J ) 1.8 Hz, 1.8 Hz, 1 H),
8.36 (d, J ) 4.5 Hz, 1 H), 10.31 (s, 1 H). Anal. (C16H15ClN2O2)
C, H, N, Cl.
3-[2-(3-Br om op h en yl)a cetyla m in o]ben zoic Acid (4b).
To a solution of the ester 4a (1.65 g, 4.56 mmol) in THF (15
mL) was added a KOH solution (0.60 g of KOH in 2 mL of
water, 9.12 mmol). After the resulting solution was stirred at
60 °C for 11 h, water (20 mL) was added; subsequently, THF
was removed under reduced pressure. This water solution was
then acidified by the addition of 2 N HCl solution, and the
precipitates formed were filtered and were then washed with
water to afford the titled compound (1.42 g, yield 93%): mp
249-250 °C; IR (KBr) 3272, 1692, 1663, 1591, 1537; 1H NMR
(DMSO-d6) 3.66 (s, 2 H), 7.20-7.40 (m, 4 H), 7.53 (s, 1 H),
7.60 (d, J ) 7.8 Hz, 1 H), 7.73 (d, J ) 7.8 Hz, 1 H), 8.19 (s, 1
H), 10.33 (s, 1H), 12.83 (s, 1 H). Anal. (C15H12BrNO3) C, H,
N, Br.
3-[2-(3-Br om op h e n yl)a ce t yla m in o]-N -m e t h ylb e n z-
a m id e (1): mp 176-178 °C; IR (KBr) 3324, 3254, 1642, 1591,
1554; NMR (DMSO-d6) 2.76 (d, J ) 4.5 Hz, 3 H), 3.68 (s, 2 H),
7.27-7.41 (m, 3 H), 7.45-7.50 (m, 2 H), 7.56 (s, 1 H), 7.75 (d,
J ) 8.0 Hz, 1 H), 8.03 (s, 1 H), 8.42 (d, J ) 4.5 Hz, 1 H), 10.35
(s, 1 H). Anal. (C16H15BrN2O2) C, H, N, Br.
3-[2-(3-Br om op h en yl)a cetyla m in o]-N,N-d im eth ylben z-
a m id e (4d ). To a solution of the benzoic acid derivative 4b
(167 mg, 0.50 mmol) in THF (5 mL), oxalyl chloride (67 mg,
0.53 mmol) and one drop of DMF were added. The resulting
solution was then stirred for 1 h at room temperature, and
50% dimethylamine solution in water (0.45 mL, 5.0 mmol) was
added. After being stirred for 4 h at room temperature, the
mixture was extracted with AcOEt. Combined extracts were
washed with saturated NaCl solution and were then dried over
MgSO4. Filtration of the drying agent and removal of the
solvents yielded the crude product, which was purified by
recrystallization from an AcOEt (1.5 mL) and hexane (1.5 mL)
mixture, to give the desired compound (112 mg, yield 62%):
mp 119-120 °C; IR (KBr) 1678, 1613, 1588, 1557; 1H NMR
(DMSO-d6) 2.90 (s, 3 H), 2.96 (s, 3 H), 3.68 (s, 2 H), 7.06 (d,
J ) 7.8 Hz, 1 H), 7.25-7.41 (m, 3 H), 7.47 (m, 1 H), 7.53-7.60
(m, 2 H), 7.68 (s, 1 H), 10.30 (s, 1 H). Anal. (C17H17BrN2O2)
C, H, N, Br.
3-[2-(3-Br om op h en yl)a cetyla m in o]ben za m id e (4c): mp
202 °C; IR (KBr) 3378, 3295, 1659, 1624, 1586, 1534; 1H NMR
(DMSO-d6) 3.67 (s, 2 H), 7.20-7.60 (m, 7 H), 7.76 (d, J ) 9.3
Hz, 1 H), 7.94 (s, 1 H), 8.03 (s, 1 H), 10.33 (s, 1 H). Anal.
(C15H13BrN2O2) C, H, N, Br.
N-Meth yl-3-(p h en yla cetyla m in o)ben za m id e (7a ): mp
1
140-142 °C; H NMR (DMSO-d6) 2.75 (d, J ) 4.5 Hz, 3 H),
3.63 (s, 2 H), 7.22-7.48 (m, 7 H), 7.74 (m, 1 H), 8.01 (s, 1 H),
8.37 (d, J ) 4.5 Hz, 1 H), 10.30 (s, 1 H). Anal. (C16H16N2O2) C,
H, N.
3-[2-(3-F lu or op h e n yl)a ce t yla m in o]-N -m e t h ylb e n z-
a m id e (7b): mp 147-148 °C; IR (KBr) 3314, 1661, 1636,
1587, 1530; 1H NMR (DMSO-d6) 2.76 (d, J ) 4.2 Hz, 3 H),
3.69 (s, 2 H), 7.08 (dd, J ) 5.7 Hz, 5.7 Hz, 1 H), 7.14 (d, J )
7.5 Hz, 2 H), 7.38 (m, 2 H), 7.47 (d, J ) 8.1 Hz, 1 H), 7.74 (d,
J ) 8.1 Hz, 1 H), 8.02 (s, 1 H), 8.35 (d, J ) 4.2 Hz, 1 H), 10.30
(s, 1 H). Anal. (C16H15FN2O2) C, H, N, F.
3-[2-(3-B r o m o p h e n y l)a c e t y la m in o ]-N -e t h y lb e n z-
a m id e (4e): mp 155 °C; IR (KBr) 3329, 3268, 1665, 1640,
1
1549; H NMR (DMSO-d6) 1.11 (t, J ) 6.9 Hz, 3 H), 3.29 (m,
2 H), 3.67 (s, 2 H), 7.20-7.40 (m, 3 H), 7.47 (d, J ) 8.1 Hz,
1 H), 7.49 (d, J ) 8.1 Hz, 1 H), 7.56 (s, 1 H), 7.75 (d, J ) 8.4
Hz, 1 H), 8.00 (s, 1 H), 8.41 (t, J ) 5.1 Hz, 1 H), 10.32 (s, 1 H).
Anal. (C17H17BrN2O2‚0.1H2O) C, H, N.
3-[2-(2-Ch lor op h e n yl)a ce t yla m in o]-N -m e t h ylb e n z-
a m id e (7c): mp 211-212 °C; IR (KBr) 3268, 1659, 1642, 1586,
1535; 1H NMR (DMSO-d6) 2.77 (d, J ) 3.6 Hz, 3 H), 3.85 (s, 2
H), 7.25-7.55 (m, 6 H), 7.74 (d, J ) 7.5 Hz, 1 H), 8.04 (s, 1 H),
8.36 (d, J ) 3.6 Hz, 1 H), 10.34 (s, 1 H). Anal. (C16H15ClN2O2)
C, H, N.
3-[2-(3-Br om op h en yl)a cet yla m in o]-N-h yd r oxyb en z-
a m id e (4f): mp 184-186 °C (dec); IR (KBr) 3314, 3231, 1663,
1632, 1582, 1535; 1H NMR (DMSO-d6) 3.68 (s, 2 H), 7.25-
7.60 (m, 6 H), 7.75 (d, J ) 6.9 Hz, 1 H), 7.98 (s, 1 H), 9.01
(s, 1 H), 10.33 (s, 1 H), 11.12 (s, 1 H). Anal. (C15H13BrN2O3‚
0.1H2O) C, H, N.
3-[2-(4-Ch lor op h e n yl)a ce t yla m in o]-N -m e t h ylb e n z-
a m id e (7e): mp 163-164 °C; IR (KBr) 3279, 1663, 1640, 1588,
1535; 1H NMR (DMSO-d6) 2.76 (d, J ) 3.9 Hz, 3 H), 3.66 (s, 2
H), 7.35-7.42 (m, 5 H), 7.47 (d, J ) 7.8 Hz, 1 H), 7.75 (d, J )
3-[2-(3-Br om op h en yl)a cet yla m in o]-N-m et h oxyb en z-
a m id e (4g): mp 166 °C; IR (KBr) 3299, 3187, 1659, 1611,

4472 J ournal of Medicinal Chemistry, 2001, Vol. 44, No. 25
Ando et al.
7.8 Hz, 1 H), 8.02 (dd, J ) 1.5 Hz, 1.5 Hz, 1 H), 8.36 (d, J )
3.9 Hz, 1 H), 10.30 (s, 1 H). Anal. (C16H15ClN2O2‚0.3H2O) C,
H, N.
3-[2-(4-Br om op h e n yl)a ce t yla m in o]-N -m e t h ylb e n z-
a m id e (7f): mp 165-166 °C; IR (KBr) 3283, 1665, 1642, 1588,
1534; 1H NMR (DMSO-d6) 2.77 (d, J ) 4.5 Hz, 3 H), 3.64 (s, 2
H), 7.23-7.40 (m, 3 H), 7.40-7.58 (m, 3 H), 7.75 (d, J ) 7.8
Hz, 1 H), 8.01 (s, 1 H), 8.37 (d, J ) 4.5 Hz, 1 H), 10.30 (s, 1 H).
Anal. (C16H15BrN2O2‚0.5H2O) C, H, N.
N -Me t h yl-3-[2-(3-m e t h ylp h e n yl)a ce t yla m in o]b e n z-
a m id e (7g): mp 131 °C; IR (KBr) 3299, 1659, 1634, 1586,
1530; 1H NMR (DMSO-d6) 2.29 (s, 3 H), 2.76 (d, J ) 4.5 Hz, 3
H), 3.60 (s, 2 H), 7.06 (d, J ) 6.9 Hz, 1 H), 7.09-7.22 (m, 3 H),
7.36 (dd, J ) 7.8 Hz, 7.8 Hz, 1 H), 7.47 (d, J ) 7.8 Hz, 1 H),
7.75 (d, J ) 7.8 Hz, 1 H), 8.02 (s, 1 H), 8.35 (d, J ) 4.5 Hz, 1
H), 10.26 (s, 1 H). Anal. (C17H18N2O2) C, H, N.
3-[2-(3-Met h oxyp h en yl)a cet yla m in o]-N-m et h ylb en z-
a m id e (7h ): mp 104-106 °C; 1H NMR (DMSO-d6) 2.76 (d,
J ) 4.5 Hz, 3 H), 3.60 (s, 2 H), 3.73 (s, 3 H), 6.81 (m, 1 H),
6.89-6.92 (m, 2 H), 7.23 (m, 2 H), 7.35 (m, 1 H), 7.47 (m, 1
H), 7.76 (m, 1 H), 8.02 (s, 1 H), 8.38 (m, 1 H), 10.28 (s, 1 H).
Anal. (C17H18N2O3) C, H, N.
3-[2-(3-Ben zyloxyp h en yl)a cetyla m in o]-N-m eth ylben z-
a m id e (7i): mp 150 °C; IR (KBr) 3302, 1661, 1634, 1586, 1530;
1H NMR (DMSO-d6) 2.76 (d, J ) 4.5 Hz, 3 H), 3.61 (s, 2 H),
5.09 (s, 2 H), 6.91 (dd, J ) 7.8 Hz, 7.8 Hz, 2 H), 7.01 (s, 1 H),
7.27 (dd, J ) 7.8 Hz, 7.8 Hz, 1 H), 7.25-7.52 (m, 7 H), 7.74 (d,
J ) 7.8 Hz, 1 H), 8.02 (s, 1 H), 8.36 (d, J ) 4.5 Hz, 1 H), 10.27
(s, 1 H). Anal. (C23H22N2O3) C, H, N.
N -Me t h y l-3-[2-(3-n it r o p h e n y l)a c e t y la m in o ]b e n z-
a m id e (7j): mp 139 °C; IR (KBr) 3322, 3250, 1665, 1640,
1555, 1524; 1H NMR (DMSO-d6) 2.76 (d, J ) 4.5 Hz, 3 H),
3.86 (s, 2 H), 7.37 (dd, J ) 7.8 Hz, 7.8 Hz, 1 H), 7.49 (d, J )
7.8 Hz, 1 H), 7.64 (dd, J ) 8.1 Hz, 8.1 Hz, 1 H), 7.75 (d, J )
8.1 Hz, 1 H), 7.80 (d, J ) 8.1 Hz, 1 H), 8.03 (s, 1 H), 8.13 (d,
J ) 8.1 Hz, 1 H), 8.24 (s, 1 H), 8.37 (d, J ) 4.5 Hz, 1 H), 10.39
(s, 1 H). Anal. (C16H15N3O4) C, H, N.
Hz, 3 H), 3.55 (s, 2 H), 5.98 (s, 2 H), 6.74-6.93 (m, 3 H), 7.36
(dd, J ) 7.8 Hz, 7.8 Hz, 1 H), 7.47 (d, J ) 7.8 Hz, 1 H), 7.75
(d, J ) 7.8 Hz, 1 H), 8.01 (s, 1 H), 8.35 (d, J ) 4.5 Hz, 1 H),
10.20 (s, 1 H). Anal. (C17H16N2O4) C, H, N.
3-[2-(3-1H -I n d o ly l)a c e t y la m i n o ]-N -m e t h y lb e n z -
a m id e (7q): mp 168-169 °C; IR (KBr) 3382, 3287, 1655,
1
1636, 1588, 1555, 1528; H NMR (DMSO-d6) 2.73 (d, J ) 4.5
Hz, 3 H), 3.72 (s, 2 H), 6.96 (dd, J ) 7.5 Hz, 7.5 Hz, 1 H), 7.05
(dd, J ) 7.8 Hz, 7.8 Hz, 1 H), 7.24 (s, 1 H), 7.27-7.38 (m, 2
H), 7.43 (d, J ) 7.8 Hz, 1 H), 7.59 (d, J ) 7.8 Hz, 1 H), 7.75 (d,
J ) 8.7 Hz, 1 H), 8.00 (s, 1 H), 8.32 (d, J ) 4.5 Hz, 1 H), 10.18
(s, 1 H), 10.88 (s, 1 H). Anal. (C18H16N3O2) C, H, N.
N-Meth yl-3-(3-p h en ylp r op ion yla m in o)ben za m id e (7r ):
mp 142-143 °C; IR (KBr) 3295, 1657, 1613, 1593, 1545; 1H
NMR (DMSO-d6) 2.62 (t, J ) 7.8 Hz, 2 H), 2.75 (d, J ) 4.5 Hz,
3 H), 2.90 (t, J ) 7.8 Hz, 2 H), 7.10-7.40 (m, 6 H), 7.44 (d,
J ) 7.5 Hz, 1 H), 7.72 (d, J ) 7.5 Hz, 1 H), 7.99 (s, 1 H), 8.33
(d, J ) 4.5 Hz, 1 H), 10.00 (s, 1 H). Anal. (C17H18N2O2) C,
H, N.
3-[3-(2-Meth oxyph en yl)pr opion ylam in o]-N-m eth ylben z-
1
a m id e (7s): mp 150 °C; IR (KBr) 3297, 1658, 1644, 1550; H
NMR (DMSO-d6) 2.56 (t, J ) 7.2 Hz, 2 H), 2.75 (d, J ) 3.9 Hz,
3 H), 2.85 (t, J ) 7.2 Hz, 2 H), 3.78 (s, 3 H), 6.84 (dd, J ) 7.5
Hz, 7.5 Hz, 1 H), 6.93 (d, J ) 7.5 Hz, 1 H), 7.05-7.20 (m, 2
H), 7.26 (dd, J ) 8.1 Hz, 8.1 Hz, 1 H), 7.34 (d, J ) 8.1 Hz, 1
H), 7.72 (d, J ) 8.1 Hz, 1 H), 7.99 (s, 1 H), 8.38 (d, J ) 3.9 Hz,
1 H), 9.67 (s, 1 H). Anal. (C18H20N2O3) C, H, N.
N-Meth yl-3-(2-ph en oxyacetylam in o)ben zam ide (7t): mp
131 °C; IR (KBr) 3378, 3283, 1669, 1640, 1588, 1535; 1H NMR
(DMSO-d6) 2.75 (d, J ) 4.5 Hz, 3 H), 4.69 (s, 2 H), 6.63-7.01
(m, 3 H), 7.22-7.40 (m, 3 H), 7.50 (d, J ) 7.8 Hz, 1 H), 7.77
(d, J ) 7.8 Hz, 1 H), 8.05 (s, 1 H), 8.36 (d, J ) 4.5 Hz, 1 H),
10.18 (s, 1 H). Anal. (C16H16N2O3) C, H, N.
3-[2-(2,3-Dich lor oph en oxy)acetylam in o]-N-m eth ylben z-
a m id e (7u ): mp 192-193 °C; IR (KBr) 3385, 3291, 1692,
1644, 1547; 1H NMR (DMSO-d6) 2.77 (d, J ) 4.5 Hz, 3 H),
4.91 (s, 2 H), 7.08 (d, J ) 8.1 Hz, 1 H), 7.20-7.45 (m, 3 H),
7.52 (d, J ) 7.8 Hz, 1 H), 7.74 (d, J ) 8.7 Hz, 1 H), 8.05 (s, 1
3-[2-(3-H yd r oxyp h en yl)a cet yla m in o]-N-m et h ylb en z-
1
a m id e (7k ): mp 188-189 °C; H NMR (DMSO-d6) 3.52 (s, 2
H), 8.42 (d, J ) 4.5 Hz, 1 H), 10.34 (s, 1 H). Anal. (C16H14
Cl2N2O3) C, H, N.
-
H), 6.62 (m, 1 H), 6.72-6.75 (m, 2 H), 7.08 (m, 1 H), 7.32-
7.37 (m, 2 H), 7.51 (d, J ) 6.9 Hz, 1 H), 7.76 (d, J ) 7.8 Hz, 1
H), 7.92 (s, 1 H), 8.02 (s, 1 H), 9.34 (s, 1 H), 10.25 (s, 1 H).
Anal. (C16H16N2O3) C, H, N.
N-Met h yl-3-[2-(1-n a p h t h oxy)a cet yla m in o]b en za m id e
1
(7v): mp 194 °C; IR (KBr) 3405, 3304, 1696, 1638, 1541; H
NMR (DMSO-d6) 2.75 (d, J ) 4.2 Hz, 3 H), 4.92 (s, 2 H), 6.92
(d, J ) 7.8 Hz, 1 H), 7.33-7.62 (m, 6 H), 7.79 (d, J ) 8.1 Hz,
1 H), 7.88 (m, 1 H), 8.08 (s, 1 H), 8.31 (m, 1 H), 8.41 (d, J )
4.2 Hz, 1 H), 10.36 (s, 1 H). Anal. (C20H18N2O3‚0.1H2O) C, H,
N.
N-Met h yl-3-[2-(2-n a p h t h oxy)a cet yla m in o]b en za m id e
(7w ): mp 174 °C; IR (KBr) 3382, 3275, 1672, 1638, 1588, 1557,
1534; 1H NMR (DMSO-d6) 2.75 (d, J ) 4.5 Hz, 3 H), 4.82 (s, 2
H), 7.22-7.58 (m, 6 H), 7.78-7.95 (m, 4 H), 8.09 (s, 1 H), 8.40
(d, J ) 4.5 Hz, 1 H), 10.28 (s, 1 H). Anal. (C20H18N2O3) C,
H, N.
(3-Meth ylca r ba m oylp h en yl)ca r ba m ic Acid 4-Meth yl-
ben zyl Ester (11a ). To a solution of 4-methylbenzyl alcohol
(307 mg, 2.52 mmol) and di(N-succinimidyl) carbonate 9 (966
mg, 3.77 mmol) in CH2Cl2 (20 mL) was added triethylamine
(0.70 mL, 5.03 mmol), and the resulting solution was stirred
for 4 h at room temperature. Water (20 mL) was then added,
and the water layer was extracted with CH2Cl2. Combined
extracts were washed with saturated NaCl, saturated NaH-
CO3, saturated NaCl, 2 N HCl, and saturated NaCl succes-
sively, and they were then dried over MgSO4. Filtration of the
drying agent and removal of the solvents yielded the inter-
mediate, which was dissolved in DMF (2 mL), and 3-amino-
N-methylbenzamide 6 (341 mg, 2.27 mmol) and triethylamine
(0.35 mL, 2.52 mmol) were added. After the mixture was
stirred at room temperature overnight, the insoluble solid was
filtered. The filtrate was then added to water (15 mL), and
the precipitates formed were filtered and were then washed
with water. After drying, this crude product was added to
AcOEt (8 mL), and the resulting suspension was refluxed for
10 min. The mixture was then cooled to room temperature,
3-(2-Cycloh exyla cetyla m in o)-N-m eth ylben za m id e (7l):
1
mp 183 °C; IR (KBr) 3293, 1657, 1640, 1588, 1535; H NMR
(DMSO-d6) 0.99 (m, 2 H), 1.03-1.38 (m, 3 H), 1.55-1.90 (m, 6
H), 2.19 (d, J ) 7.0 Hz, 2 H), 2.76 (d, J ) 4.5 Hz, 3 H), 7.34
(dd, J ) 7.8 Hz, 7.8 Hz, 1 H), 7.45 (d, J ) 7.8 Hz, 1 H), 7.74
(d, J ) 7.8 Hz, 1 H), 8.01 (s, 1 H), 8.34 (d, J ) 4.5 Hz, 1 H),
9.95 (s, 1 H). Anal. (C16H22N2O2) C, H, N.
N -Me t h yl-3-[2-(1-n a p h t h yl)a ce t yla m in o]b e n za m id e
(7m ): mp 201-202 °C; IR (KBr) 3274, 1657, 1640, 1588, 1532;
1H NMR (DMSO-d6) 2.75 (d, J ) 4.5 Hz, 3 H), 4.16 (s, 2 H),
7.36 (dd, J ) 8.1 Hz, 8.1 Hz, 1 H), 7.40-7.60 (m, 5 H), 7.74 (d,
J ) 7.8 Hz, 1 H), 7.84 (d, J ) 7.8 Hz, 1 H), 7.97 (d, J ) 7.8 Hz,
1 H), 8.03 (s, 1 H), 8.35 (d, J ) 7.8 Hz, 1 H), 8.37 (d, J ) 4.5H
z, 1 H), 10.44 (s, 1 H). Anal. (C20H18N2O2) C, H, N.
N-Meth yl-3-[2-(2-n aph th yl)acetylam in o]ben zam ide (7n ):
mp 175-176 °C; IR (KBr) 3393, 1655, 1634, 1588, 1530; 1H
NMR (DMSO-d6) 2.76 (d, J ) 4.5 Hz, 3 H), 3.83 (s, 2 H), 7.37
(dd, J ) 7.8 Hz, 7.8 Hz, 1 H), 7.40-7.55 (m, 4 H), 7.77 (d, J )
8.4 Hz, 1 H), 7.81-7.96 (m, 4 H), 8.04 (s, 1 H), 8.36 (d, J ) 4.5
Hz, 1 H), 10.37 (s, 1 H). Anal. (C20H18N2O2) C, H, N.
3-[2-(3-b en zo[b]t h ien yl)a cet yla m in o]-N-m et h ylb en z-
a m id e (7o): mp 194 °C; IR (KBr) 3285, 1663, 1636, 1588,
1532; 1H NMR (DMSO-d6) 2.75 (d, J ) 4.2 Hz, 3 H), 3.94 (s, 2
H), 7.32-7.53 (m, 4 H), 7.61 (s, 1 H), 7.76 (d, J ) 6.9 Hz, 1 H),
7.91 (d, J ) 7.2 Hz, 1 H), 7.98 (d, J ) 7.2 Hz, 1 H), 8.04 (s, 1
H), 8.35 (d, J ) 4.2 Hz, 1 H), 10.40 (s, 1 H). Anal. (C18H16N2O2S)
C, H, N, S.
3-[2-(5-Ben zo[1,3]dioxolyl)acetylam in o]-N-m eth ylben z-
a m id e (7p ): mp 174-175 °C; IR (KBr) 3337, 3291, 1659,
1
1634, 1586, 1530, 1505; H NMR (DMSO-d6) 2.76 (d, J ) 4.5

Novel Class of Selective Anti-H. pylori Agents
J ournal of Medicinal Chemistry, 2001, Vol. 44, No. 25 4473
and crystals were filtered and washed with AcOEt to afford
the desired compound (182 mg, yield 27%): mp 167-168 °C;
IR (KBr) 3322, 1738, 1622, 1557; 1H NMR (DMSO-d6) 2.28 (s,
3 H), 2.74 (d, J ) 4.6 Hz, 3 H), 5.09 (s, 2 H), 7.17 (d, J ) 7.9
Hz, 2 H), 7.23-7.42 (m, 4 H), 7.54 (d, J ) 6.5 Hz, 1 H), 7.91
(s, 1 H), 8.31 (d, J ) 4.6 Hz, 1 H), 9.82 (s, 1 H). Anal.
(C17H18N2O3) C, H, N.
(3-Meth ylcar bam oylph en yl)car bam ic acid 4-ch lor oben -
zyl ester (11b): mp 155-156 °C; IR (KBr) 3351, 3299, 1734,
1624, 1557; 1H NMR (DMSO-d6) 2.74 (d, J ) 4.5 Hz, 3 H),
5.14 (s, 2 H), 7.25-7.43 (m, 6 H), 7.55 (d, J ) 8.3 Hz, 1 H),
7.91 (s, 1 H), 8.32 (d, J ) 4.5 Hz, 1 H), 9.88 (s, 1 H). Anal.
(C16H15ClN2O3) C, H, N, Cl.
except for the medium (potato dextrose agar) and incubation
conditions (at 27 °C for 24 h).
Ack n ow led gm en t. The authors thank Dr. Takeshi
Itoh, former Director, Microorganism Department, To-
kyo Metropolitan Research Laboratory of Public Health,
for his practical advice about the cultivation of H. pylori
and to Dr. Takashi Mikawa and Ms. Mina Kanda,
Mitsubishi Chemical Corporation, for their valued as-
sistance. We also appreciate Dr. Intetsu Kobayashi,
Mitsubishi Kagaku B.C.L. Inc., for discussions.
(3-Meth ylca r ba m oylp h en yl)ca r ba m ic a cid 2,6-d ih lo-
r oben zyl ester (11c): mp 219-220 °C; IR (KBr) 3380, 3241,
1717, 1651, 1562; 1H NMR (DMSO-d6) 2.74 (d, J ) 4.3 Hz,
3 H), 5.35 (s, 2 H), 7.25-7.60 (m, 6 H), 7.92 (s, 1 H), 8.35
(d, J ) 4.3 Hz, 1 H), 9.92 (s, 1H). Anal. (C16H14Cl2N2O3) C, H,
N, Cl.
Refer en ces
(1) Marshall, B. J .; Warren, J . R. Unidentified curved bacilli in the
stomach of patients with gastritis and peptic ulceration. Lancet
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Gasbarrini, G. Extradigestive manifestations of Helicobacter
pylori gastric infection. Gut 1999, 45 (Suppl I), I9-I12.
(4) (a) Sjo¨stro¨m, J .-E.; Fryklund, J .; Ku¨hler, T.; Larsson, H. In Vitro
Antibacterial Activity of Omeprazole and Its Selectivity for
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Antimicrob. Agents Chemther. 1996, 40, 621-626. (b) Sjo¨stro¨m,
J .-E.; Ku¨hler, T.; Larsson, H. Basis for the Selective Antibacte-
rial Activity In Vitro of Proton Pump Inhibitors against Heli-
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1801.
(5) (a) Katsura, Y.; Nishino, S.; Tomishi, T.; Sakane, K.; Matsumoto,
Y.; Ishikawa, H.; Takasugi, H. Anti-Helicobacter pylori agents.
2. Structure activity relationships in a new series of 2-alkyl-
guanidino-4-furylthiazoles. Bioorg. Med. Chem. Lett. 1998, 8,
1307-1312. (b) Katsura, Y.; Nishino, S.; Ohno, M.; Sakane, K.;
Matsumoto, Y.; Morinaga, C.; Ishikawa, H.; Takasugi, H. Anti-
Helicobacter pylori agents. 3. 2-[(Arylalkyl)guanidino]-4-furyl-
thiazoles. J . Med. Chem. 1999, 42, 2920-2926. (c) Katsura, Y.;
Tomishi, T.; Inoue, Y.; Sakane, K.; Matsumoto, Y.; Morinaga,
C.; Ishikawa, H.; Takasugi, H. Anti-Helicobacter pylori agents.
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turally Rigid Derivatives. J . Med. Chem. 2000, 43, 3315-3321.
(6) Yoshida, Y.; Barrett, D.; Azami, H.; Morinaga, C.; Matsumoto,
Y.; Takasugi, H. Discovery of a novel benzyloxyisoquinoline
derivative with potent anti-Helicobacter pylori activity. Bioorg.
Med. Chem. Lett. 1998, 8, 1897-1902. (b) Yoshida, Y.; Barrett,
D.; Azami, H.; Morinaga, C.; Matsumoto, S.; Matsumoto, Y.;
Takasugi, H. Studies on Anti-Helicobacter pylori Agents. Part
1: Benzyloxyisoquinoline Derivatives. Bioorg. Med. Chem. 1999,
7, 2647-2666.
(3-Meth ylca r ba m oylp h en yl)ca r ba m ic a cid 1-n a p h th yl-
m eth l ester (11d ): mp 228-229 °C; IR (KBr) 3353, 3285,
1
1730, 1626, 1555; H NMR (DMSO-d6) 2.76 (d, J ) 4.4 Hz, 3
H), 5.64 (s, 2 H), 7.30-7.45 (m, 2 H), 7.50-7.70 (m, 5 H), 7.90-
8.03 (m, 3 H), 8.12 (d, J ) 7.6 Hz, 1 H), 8.38 (d, J ) 4.4 Hz, 1
H), 9.87 (s, 1 H). Anal. (C20H18N2O3) C, H, N.
(3-Meth ylca r ba m oylp h en yl)ca r ba m ic a cid 2-n a p h th yl-
m eth l ester (11e): mp 157-158 °C; IR (KBr) 3314, 1699,
1
1642, 1589, 1539; H NMR (DMSO-d6) 2.76 (d, J ) 4.8 Hz, 3
H), 5.32 (s, 2 H), 7.23-7.42 (m, 2 H), 7.42-7.60 (m, 4 H), 7.82-
7.98 (m, 5 H), 8.32 (d, J ) 4.8 Hz, 1 H), 9.90 (s, 1 H). Anal.
(C20H18N2O3) C, H, N.
Mea su r em en t of An ti-H. pylor i Activity. A H. pylori
strain 31A was grown in a liquid medium (5 mL) containing
brain-heart infusion broth with 10% fetal bovine serum in a
test tube on a shaker under slightly aerobic conditions (5%
O2, 10% CO2, 85% N2) at 37 °C for 48 h. This culture was then
inoculated to brain-heart infusion broth containing 10% fetal
bovine serum at a ratio of 5%, and the 10% DMSO solution of
a test compound was added at a ratio of 10%. The 10% DMSO
solution was used as the reference test. Cultivation was carried
out under slightly aerobic conditions described above at 37 °C
for 48 h by shaking, and growth of H. pylori was then
examined. Antibacterial activity was recorded as the lowest
concentration at which the compound exhibited bacterial
growth inhibition (minimum inhibitory concentration: MIC).
(7) Ishikawa, H.; Ito, H.; Higaki, M.; Higaki, M.; Matsumoto, Y.;
Kamimura, T.; Katsura, Y.; Tomishi, T.; Inoue, Y.; Takasugi,
H.; Tomoi, M.; Krakowka, S.; Yoshida, K. FR145715, a novel
histamine H2 receptor antagonist, with specific anti-Helicobacter
pylori activities. Eur. J . Pharm. 1999, 378, 299-310.
(8) Dekker, K. A.; Inagaki, T.; Gootz, T. D.; Kaneda, K.; Nomura,
E.; Sakakibara, T.; Sakemi, S.; Sugie, Y.; Yamauchi, Y.; Yoshika-
wa, N.; Kojima, Y. CJ -12,954 and Its Congeners, New Anti-
Helicobacter pylori Compounds Produced by Phanerochaete
velutina: Fermentation, Isolation, Structure Elucidation and
Biological Activities. J . Antibiot. 1997, 50, 833-839.
(9) Dekker, K. A.; Inagaki, T.; Gootz, T. D.; Huang, L. H.; Kojima,
Y.; Kohlbrenner, W. E.; Matsunaga, Y.; McGuirk, P. R.; Nomura,
E.; Sakakibara, T.; Sakemi, S.; Suzuki, Y.; Yamauchi, Y.; Kojima,
N. New Quinolone Compounds from Pseudonocardia sp. with
Selective and Potent Anti-Helicobacter pylori Activity: Tax-
onomy of Producing Strain, Fermentation, Isolation, Structure
Elucidation and Biological Activities. J . Antibiot. 1998, 51, 145-
152.
(10) Hamasaki, N.; Ishii E.; Tominaga, K.; Tezuka, Y.; Nagaoka, T.;
Kadota, S.; Kuroki, T.; Yano, I. Highly Selective Antibacterial
Activity of Novel Alkyl Quinolone Alkaloids from a Chinese
Herbal Medicine, Gosyusyu (Wu-Chu-Yu), against Helicobacter
pylori In Vitro. Microbiol. Immunol. 2000, 44, 9-15.
(11) Ohsaki, A.; Takashima, J .; Chiba, N.; Kawamura, M. Mi-
croanalysis of a selective potent anti-Helicobacter pylori com-
pound in a Brazilian medicinal plant, Myroxylon puruiferum and
the activity of analogues. Bioorg. Med. Chem. Lett. 1999, 9,
1109-1112.
An ti-H. pylor i Activity u n d er Acid ic Con d ition s. The
liquid media aforementioned was adjusted to pH 7.0, 6.0, and
5.0 by addition of HCl and NaOH solution,18 and anti-H. pylori
activity was evaluated in a manner similar to the measure-
ment method of the above normal condition.
Mea su r em en t of An t ib a ct er ia l Act ivit y excep t for
Ba cter oid es fr a gilis. The Neutrient agar containing 0.5% of
yeast extract (10 mL), in which 106-107 CFUs of test bacteria
were inoculated, was poured onto a plate. After caking, a hole
(4 mm diameter) was made with a pipe of stainless steel.
Subsequently, 50 µL of the 10% DMSO solution of a test
compound (1000 µg/mL) was added to the hole. The 10%
DMSO solution was used as the reference solution. After being
allowed to stand for 1 h at 8 °C to diffuse a test compound
into the medium, the agar was incubated at 37 °C for 18 h.
Antibacterial activity was confirmed by the formation of an
inhibitory zone.
Mea su r em en t of An t i-Ba cter oid es fr a gilis Act ivit y.
The anti-Bacteroides fragilis activity was evaluated in a
manner similar to the method described above except for the
incubation method. After the diffusion of a test compound, the
plate was placed in a pot for anaerobic bacteria cultivation.
The interior of the pot was modified to anaerobic conditions
by using a gas pack (BBL Microbiology Systems), and the
medium was incubated at 37 °C for 18 h.
(12) Taniguchi, M.; Watanabe, M.; Nagai, K.; Suzumura, K.; Suzuki,
K.; Tanaka, A. γ-Pyrone Compounds with Selective and Potent
Anti-Helicobacter pylori Activity. J . Antibiot. 2000, 53, 844-847.
(13) Copeland, R. A.; Marcinkeviciene, J .; Haque, T. S.; Kopcho, L.
M.; J iang, W.; Wang, K.; Ecret, L. D.; Sizemore, C.; Amsler, K.
Mea su r em en t of An ti-Ca n d id a a lbica n s Activity. The
anti-Candida albicans activity was evaluated in a manner
similar to the measurement method of antibacterial activity

4474 J ournal of Medicinal Chemistry, 2001, Vol. 44, No. 25
Ando et al.
A.; Foster, L.; Tadesse, S.; Combs, A. P.; Stern, A. M.; Trainor,
G. L.; Slee, A.; Rogers, M. J .; Hobbs, F. Helicobacter pylori-
selective Antibacterials Based on Inhibition of Pyrimidine Bio-
synthesis. J . Biol. Chem. 2000, 275, 33373-33378.
(16) Anti-H. pylori activity of 4-F, 4-Me, 4-MeO, 4-NO2, and 4-OH
derivatives was similar to that of corresponding 3-substituted
derivatives 7b, 7g, 7h , 7j, and 7k , respectively.
(17) Brain-heart infusion broth containing 10% fetal bovine serum,
which was used in usual screening, showed pH 7.2-7.3.
(18) Addition of phosphate buffer to the broth influenced the growth
of H. pylori.
(14) One of drawbacks of amoxicillin and clarithromycin is decom-
position under acidic conditions, which leads to decrease of
antibacterial activity in the stomach.
(15) Workup of the reaction mixture followed by recrystallization
afforded a pure product in most cases.
J M010307O