A synthetic receptor for the Cbz-L-Ala-L-Ala-OH dipeptide sequence

Abstract

A novel bowl-shaped macrobicyclic receptor has been prepared and is a particularly strong and selective receptor for Cbz-L-Ala-L-Ala-OH (–ΔG_ass = 25 kJ mol^–1 at 293 K in CDCl₃).

References

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11. In view of the selectivity of macrobicycle 13for Cbz-L-Ala-L-Ala-OH over Cbz-D-Ala-D-Ala-OH (Table 1, entries 5 and 6), and for Cbz-L-Ala-OH over Cbz-D-Ala-OH (entries 2 and 3), the preference for Cbz-Gly-D-Ala-OH over Cbz-Gly-L-Ala-OH (entries 7 and 8) is somewhat surprising. The origin of this selectivity is unclear at this stage and will need to be examined in further studies.