Synthesis and biological activities of phenylahistin derivatives

X-ray crystallographic analysis was performed and several phenylahistin der ivatives were synthesized to elucidate the structural components necessary for the anti-microtubule activity of phenylahistin. We primarily focused on the unique isoprenylated dehydrohistidine structure. Our results showed th at a uniplanar pseudo-three-ring structure formed by the hydrogen bonding o f diketopiperazine and imidazole rings is important for the anti-microtubul e activity of phenylahistin. (C) 1999 Elsevier Science Ltd. All rights rese rved.