9GUENIN E, MONTEIL M, BOUCHEMAL N, et al. Syntheses of phosphonic esters of alendronate, pamidronate and neridronate[J]. Eur J Org Chem,2007,(20):3380-3391.
10KUMAR A, DIKE S Y, NIJASURE A M, et al. Process for manufacture of 4-amino-hydroxybutylidene-1,1-bisphosphonic acid and its salts:USA, US2007149486[P]. 2007.