L-Isoleucyl-L-phenylalanine dihydrate.

The structure of the title compound, C(15)H(22)N(2)O(3).2H(2)O, was derived from data collected on a very thin twinned needle. The peptide molecule is in a rare conformation normally associated with hydrophobic dipeptides that form nanotubes. Nevertheless, the present structure is divided into hydrophobic and hydrophilic layers.