Biologically active peptides and compositions, their use

摘要

Derivatives of hemiasterlin or Geodiamolide G having anti-mitotic activities and useful in treating cancer. These derivatives are represented by formula I wherein Y, n, R₁, R₂, R₃, R₇, R₇₀, R₇₁, R₇₂, R₇₄, and R₇₅ are as defined in the specification.