New Cladiellin-Type Diterpenoids from the South China Sea Soft Coral Cladiella krempfi : Structures and Molecular Docking Analysis in EGFRs.

Two new cladiellin-type diterpenoids ( 1 and 2 ) and four known related compounds 3 - 6 , were isolated from the South China Sea soft coral Cladiella krempfi . Compound 2 is the third example of cladiellins of an unusual peroxy group in the C-6 position in C. krempfi . The structures and absolute configurations of the new compounds were established by extensive spectroscopic analysis, X-ray diffraction, and/or chemical correlation. In bioassay, all the compounds were evaluated for cytotoxicity and epidermal growth factor receptor (EGFR) inhibitory activity. A molecular docking experiment was conducted to study the structure-activity relationship of cladiellin-type diterpenoids on EGFR inhibitory activity.