Receptor polytopic

Fig. 10.1 Multiple molecular recognition of the zwitterionic amino acids by macrocyclic polytopic receptors 1,2 [28,33],...

It is also interesting to notice that these two families of poly viologen dendrimers can also act as polytopic receptors toward electron donor substrates, hosting a number of eosin dianions equal to the number of viologen units present in their branches. The data... 

Ditopic (or polytopic) receptors are those which possess two (or more) binding subunits. 

Multistability is present in systems that are interconvertible between more than two states such as polynuclear-multivalence metal complexes or polytopic receptors where one or more substrates may occupy and transfer between several different binding sites. 

Since the structure of DNA was first revealed by Watson and Crick in 1953, the formation of the double helix of nucleic acids by a self-directing, co-operative process has fascinated several generations of scientists. In general terms, DNA may be seen to self-assemble by a process in which two long chain polytopic receptors interact with the base pairs in such a way that each association step sets the stage for the one that follows. 

Axial polytopic receptors Statistical distributions and deviations... 

Reetz et al. have published a heterotopic receptor, which in addition to a crown ether moiety for complexation of potassium cations, contains a g-bonded Lewis acidic boron center that is able to form a tetracoordinated adduct with anions and with a selectivity for fluoride anions [ref 31]. Novel artificial polytopic receptors for binding of zwitterionic aminocarboxylates have been also published [ref 32]. 

Figure 2. Calculated structure of a dicopper/dipotassium complex of a multisite schiff base polytopic receptor molecule, containing the dibenzo-18-crown-6 moiety. Size of circles indicates atom types ranging from metal (largest) to oxygen, nitrogen, carbon, and hydrogen (smallest) respectively.

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