Unguisin B is a major analogue of a class of cyclic heptapeptides isolated from Emericella unguis (Aspergillus unguis) by Malstrom, University of Copenhagen, Denmark in 1999. Structurally, unguisuin B is comprised of only one proteogenic amino acid, L-leucine with two D-valines, two D-alanines and a D-tryptophan. Uniquely, the macrocycle of the unguisins is annealed to ɣ-aminobutyric acid. No reports of pharmacology of unguisin B have appeared in the literature to date.