أرسل هذا في رسالة قصيرة: Synthesis and properties of phospha[5]helicenes bearing an inner-rim phosphorus center

            ______   _    _     _____     ______  
    ___    /_   _// | || | ||  |  ___||  /_   _// 
   /   ||   -| ||-  | || | ||  | ||__    `-| |,-  
  | [] ||   _| ||_  | \\_/ ||  | ||__      | ||   
   \__ ||  /_____//  \____//   |_____||    |_||   
    -|_||  `-----`    `---`    `-----`     `-`'   
     `-`