00274nam a2200121   4500020001500000082001600015100001400031245004700045250000800092260002300100300000900123650002000132  a8122405509  a541.223 KAL  aKalsi,P.S  aStereochemistry conformation and mechanism  a2nd  aIndiabWileyc1990  a507p  astereochemistry