[(3S,5R,8R,9R,10R,12R,13R,14R,17S)-17-[(2R)-2,6-dihydroxy-6-methylheptan-2-yl]-12-hydroxy-4,4,8,10,14-pentamethyl-2,3,5,6,7,9,11,12,13,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-3-yl] (2S)-3-(1H-imidazol-5-yl)-2-[(2-methylpropan-2-yl)oxycarbonylamino]propanoate 在
silica gel 作用下,
以
甲苯 为溶剂,
反应 6.0h,
以57%的产率得到(20R)-3β-O-(L-histidyl)dammarane-12β,20,25-triol