Tubulysins, linear tetrapeptides produced by several strains of myxobacteria, show an extremely high toxicity
towards a wide range of cancer cell lines, with IC50 values in the nano or even picomolar range. Therefore, tubulysins and
their derivatives might be suitable candidates for the development of antitumor drugs. Several synthetic approaches for
tubulysins and derivates have been developed, which will be discussed in the review.