604 J ournal of Medicinal Chemistry, 1996, Vol. 39, No. 2
Yamada et al.
H.; Shima, N.; Doteuchi, M. Amino Acid Amides of 2-[(2-
Aminobenzyl)sulfinyl]benzimidazole as Acid-stable Prodrugs of
Potential Inhibitors of H+/K+ ATPase. Eur. J . Med. Chem. 1991,
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CDCl3) 2.09 (s, 3H), 2.36-2.63 (m, 4H), 2.71-2.79 (m, 2H),
3.90-4.40 (br, 2H), 4.19 (s, 2H), 6.57-6.66 (m, 2H), 6.95-7.08
(m, 2H), 7.33 (dd, 1H, J ) 5.0, 7.0 Hz), 7.69 (dd, 1H, J ) 1.0,
7.0 Hz), 8.44 (dd, 1H, J ) 1.0, 5.0 Hz); IR (film) 3430, 3340,
3220, 2940, 2860, 1625, 1605, 1585, 1495, 1455, 1360, 1315,
750 cm-1; EIMS m/z 336 (M+), 231, 173, 106 (base).
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Ack n ow led gm en t. We thank Drs. Mikio Takeda,
Hajime Tamaki, Ikuo Iijima, and Tsutomu Takagi of our
research laboratories for their useful comments and
encouragement throughout this study and Ms. Yoko
Yamamoto and Yuko Dainaka for their technical as-
sistance.
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