BINOL-3,3'-Dicarboxylic Acid: Resolution for the Key Intermediate of (S)-bepotastine
So-Yeon Nam1, Koteswara Rao Kamma1, Joungmo Cho2
1Research and Development Center, Molecules & Materials Co., Ltd., Daejeon, Republic of Korea.
Abstract:
(S)-Bepotastine is a highly selective histamine H1-receptor antagonist in the treatment of allergic rhinitis and other allergic diseases. We achieved a facile and convenient synthesis of (S)-bepotastine by resolving an early stage synthetic precursor. We devised a new class of resolving agent, BINOL-3,3'-dicarboxylic acid which could be considered as an axial version of tartaric acid. As the first example, we successfully resolved racemic piperidinyl ether by (S)-BINOL-3,3'-dicarboxylic acid with high optical purity. The final installation is quite straightforward and readily accomplished without any chiral loss.
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