[Synthesis of stable solvates of monosodium 2-[R*s,9S*)-(4-methoxy-6,7,8, 9-tetrahydro-5H-cyclohepta[b]pyridin-9-yl)sulfinyl]-1H-benzimidazole].
Monosodium 2-[(R*s,9S*)-(4-methoxy-6,7,8, 9-tetrahydro-5H-cyclohepta-[b]pyridin-9-yl)sulfinyl]-1H-benzimidazole (3A), a novel antiulcer agent previously reported by us, was found to be easily decomposed in weakly acidic solutions. In order to improve the stability of the parent compound, 3A, the preparation of 1-substituted benzimidazoles (4A) was attempted. However, the inhibitory effect of 4A against gastric acid secretion was less potent than that of 3A. Then 3A was solvated by EtOH or H2O to afford 5A or 6A, respectively. On the other hand, an another diastereoisomer, (R*s,9R*)-3B, was not solvated by EtOH or H2O under the same conditions. The thus obtained solvates (5A, 6A) are much more stable than that of 3A. The antiulcer activities of 5A and 6A were found to be similar to that of the parent compound (3A). Consequently, 6A was selected as an antiulcer agent for the development.
Yamada
S
S
Fukushima Research Laboratories, TOA EIYO Ltd., Japan.
Goto
T
T
Yuasa
S
S
Yamaguchi
T
T
Kogi
K
K
D000818:Animals; D000897:Anti-Ulcer Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D001562:Benzimidazoles; D003864:Depression, Chemical; D004355:Drug Stability; D005744:Gastric Acid / Q000378:metabolism; D051381:Rats; D013329:Structure-Activity Relationship
D000897:Anti-Ulcer Agents; D001562:Benzimidazoles; C084138:TY 11345