The present disclosure relates to compounds and compositions for the treatment of malarian diseases. The compounds comprise a class of halogenated alkyl-aromatic secondary metabolites, including hierridic C, or pharmaceutically acceptable salts, esters, solvates or prodrugs thereof. The compounds comprise a halogen; C1-C6 alkyl, H, COCH3, COH, CO-alkyl, or CO-aryl; and a C3-C30 alkyl. In at least one embodiment, the compound is 3-chloro-4,6-dimethoxy-2-pentadecylphenol. The present disclosure also relates to methods of obtain the compounds from a solution comprising a cyanobacterium.