The first dendritic crown ether polymers ('crowned' arborols: G1, G 2 and G3) have been synthesized and characterized. The convergent synthetic method was found to be more convenient than the divergent synthetic method. The building block in the branch was prepared from Nbenzyloxycarbonyl-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane and 3,5-bis(ethoxycarbonylmethoxy)benzoyl chloride. Since the basic repeating unit is the amino dicarboxylic acid, one can utilize the methods developed for peptide synthesis. Final products were obtained in moderate yields b y coupling of each generational fragment with a core (benzene-l,3,5-tricarbonyl trichloride) followed b y reduction of all amide linkages to tertiary amine linkages b y borane-dimethyl sulfide. The complexation ability of these 'crowned' arborols was estimated by two-phase solvent extraction of alkali picrate salts. We found that some of these arborols can solubilize proteins in organic solvents.

A novel method for modification of myoglobin by an alcohol-responsive phenylboronic acid function has been developed. A modified myoglobin can form a stable complex with poly(vinyl alcohol) in high pH region. The spectroscopic examination indicates that the complexation makes the modified myoglobin more stable against some denaturing factors than native myoglobin.

Reactive amino residues of horse heart cytochrome c were successfully modified with 4-boronobenzoic acid N-hydroxysuccinimide ester 1. The modified cytochrome c shows an enhanced peroxidase activity, which can be regulated by the addition of sugars.