Chemotherapy of malignant melanoma is still a great challenge, as no effective drugs are available. The development of melanogenesis-based drugs is a promising area of research because melanogenesis is a unique biochemical pathway operating only in melanoma cells (and their normal counterparts) so that the tumour can be targeted. We have been using cysteinylphenol, a sulphur-containing analogue of tyrosine, and derivatives for that ...