Syntheses of chiral bishomodiazacalix[4]arenes incorporating amino acid residues: Molecular recognition for racemic ammonium ions by the macrocycles possessing tyrosine residues

Article abstract of DOI:10.1002/jhet.5570370113

Chiral bishomodiazacalix[4]arenes containing amino acid residues were prepared. The ¹H and ¹³C nmr spectra indicated that the macrocycles preferably adopted a cone conformation, which suggested that the cyclophane moiety was in a chi