参考文献:
ACTELION PHARMACEUTICALS LTD AISSAOUI, Hamed BOSS, Christoph BROTSCHI, Christine KOBERSTEIN, Ralf SIEGRIST, Romain SIFFERLEN, Thierry TRACHSEL, Daniel WILLIAMS, Jodi T. Patent: WO00/44054 A, 00 Location in patent: Page/Page column 8 WO 00/044054 A