Macrocyclic oligoesters from

SELECTIVE SYNTHESIS OF MACROCYCLIC OLIGOESTERS FROM A BICY-CLIC OXALACTONE AND CATION TRANSPORT THROUGH THEIR ORGANIC LIQUID MEMBRANES... 

Selective Synthesis of Macrocyclic Oligoesters from (i)-6,8-Dioxabicyclo[3.2.1]octan-7-one... 

In other words, an ion having a larger ion diameter and smaller heat of dehydration in the alkali and alkaline earth metal series is apt to be extracted favorably with the macrocyclic oligoesters from an aqueous phase into an organic phase. The selectivity sequence of alkali metal ions above belongs to the Eisenman s sequence I [14], and it is similar to that for beauvericin [15]. On the other hand, the selectivity sequence for nonactin is Rb+ >... 

In connection with studies on the ring-opening polymerization of cyclic acetals, we have undertaken investigations on the polymerization of bicyclic acetals, bicyclic oxalactone, and bicyclic oxalactam, which yield polysaccharide analogs, macrocyclic oligoesters, and a hydrophilic polyamide, respectively, some of which can be expected to be useful as novel speciality polymers. The monomers employed in the studies were prepared via synthetic routes presented in Scheme 1, starting from 3,4-dihydro-2H-pyran-2-carbaldehyde (acrolein dimer) I. 

The ion binding strength as evaluated from the Kg values in TABLE IV is comparable to that of beauvericin [12], an eighteen-membered depsipeptide belonging to enniatins, but it is much weaker than that of nonactin [13]. For both of the macrocyclic oligoesters, the Kg values decreased in the order, Cs" > Rb > K+ > Na+ > Li , and Ba " > Ca. ... 

Cs" > Na" [16], and also in this respect, the macrocyclic oligoesters differ from nonactin. 

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