Publication
CP-225,917 and CP-263,114, novel Ras farnesylation inhibitors from an unidentified fungus. I. Taxonomy, fermentation, isolation, and biochemical properties.
During the course of our screening for squalene synthase inhibitors and Ras farnesylation inhibitors, a novel fungal culture was discovered to produce two structurally unique compounds, CP-225,917 and CP-263,114, as well as zaragozic acid A (squalestatin I). The two compounds are characterized by a bicyclo[4.3.1]dec-1,6-diene core plus two extended alkyl chains. CP-225,917 and CP-263,114 inhibit Ras farnesyl transferase from rat brain with IC50 values of 6 microM and 20 microM, respectively. CP-225,917 inhibits squalene synthase with an IC50 value of 43 microM and CP-263,114 with an IC50 of 160 microM. The producing organism, though not fully classified, exhibits the characteristics of a sterile Phoma species.