Patent ID: 6849742

Claim:
A binaphthol derivative represented by the formula [1]: wherein Y 1 , Y 1 ′, Y 2 , and Y 2 ′ may be same or different and each is selected from the group consisting of a carboxyl group, an esterified carboxyl group, a group of —(CONH)n-X (wherein X is an optionally branched and optionally substituted hydrocarbon group which may have an unsaturated bond, an optionally substituted aromatic group or a heterocyclic group having conjugated double bonds, n is an integer of 1 or 2), and a group of formula [2] wherein L is —O—, —S— or —NH—, and Z is an optionally substituted aromatic group or a heterocyclic group having conjugated double bonds; R and R′ are selected from the group consisting of hydrogen atom, an alkaline metal, an optionally branched and optionally substituted alkyl group of 1-20 carbon atoms, an acyl group and a phenylalkylene group; Q and Q′ are selected from the group consisting of optionally branched alkyl and alkoxy group of 1-6 carbon atoms, a halogen atom, nitro group and nitroso group; and m and m′ each represents an integer of 0-3 or a salt thereof.