Solid-phase synthesis and biological activity of malformin C and its derivatives.

We accomplished the solid-phase total synthesis of malformin C, which is adaptable for the easy preparation of various derivatives. A solid-phase total synthesis of malformin C was achieved by on-resin macrolactamization and disulfide bond formation, with concurrent cleavage from the resin. Antimalarial and antitrypanosomal activities were examined, which helped elucidate partial structure-activity relationships. Results indicate that the disulfide bond is essential and branched amino acids are also crucial components if the compound is to exhibit potent antimalarial and antitrypanosomal properties.