THE HOST-GUEST CHEMISTRY OF RESORCINARENES .1.

Conformations, acid-base and supramolecular properties of phenolic met acyclophanes obtained from the condensation of resorcinol with aldehyd es are discussed, including the mechanisms involved in the formation o f these macrocycles. The strong binding of choline-type compounds and the inhibition of acetylcholine hydrolysis with the rccc stereoisomers is mechanistically evaluated; a rctt isomer shows strong conformation al coupling for, e.g., choline binding and simultaneous proton release . The presence of larger alkyl residues at the bottom of the rccc macr ocycle leads to an additional binding site for small lipophilic substr ates, which is independent of the upper complexation center for positi vely charged substrates. Substitution at the upper rim by carboxylic g roups at the 2-position of the phenyl rings yields receptors for, e.g. , alpha, omega-diammonium ions with alternate equatorial and axial ary lunits. Positively charged substituents at the upper rim, introduced b y aminoalkylation, lead to little change of complexation as a result f rom their orientation away from the binding center. Aminoacid substitu ents, for the same reason, do not lead to enantioselective complexatio n, but allow particularly for strong binding of transition metal ions. Preliminary studies show that resorcinarenes bearing a wide array of positive charges are potent groove binders to ds-DNA without intercala tive contributions.