Flagpole type interaction

Here, 4 kcal of eclipsing strain is involved. In addition, a pair of hydrogens are forced to come together in a flagpole type of interaction. It is experimentally measured that each flagpole interaction (where the... 

Finally, cyclodipeptides in which both the amino acid units have aliphatic side chains have also been investigated (83BCJ1155). In the case of the cis cyclodipeptides, cyclo(L-Val)2 and cyclo(L-Leu)2, the hydro-phobic interaction between the two side chains may stabilize the planar-axial or the flagpole-boat-type conformation, respectively, in polar solvents. 

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