Empirical Formula: C₄H₁₈NNaO₁₀P₂
Molecular Weight: 325.1237
Nominal Mass: 325 Da
Average Mass: 325.1237 Da
Monoisotopic Mass: 325.030363 Da 
Flash Point: 326.7 °C
Enthalpy of Vaporization: 104.87 kJ/mol
Boiling Point: 616.7 °C at 760 mmHg
Vapour Pressure: 8.72E-18 mmHg at 25 °C
Melting point: 245 °C(lit.)
Storage tempreture: -20 °C
Solubility: Water, double-distilled: 10 mg/mL
Appearance: White crystalline solid
Structure of Alendronate sodium (CAS NO.121268-17-5):
                            
IUPAC Name: Sodium (4-amino-1-hydroxy-1-phosphonobutyl)-hydroxyphosphinate trihydrate
Canonical SMILES: C(CC(O)(P(=O)(O)O)P(=O)(O)[O-])CN.O.O.O.[Na+]
InChI: InChI=1S/C4H13NO7P2.Na.3H2O/c5-3-1-2-4(6,13(7,8)9)14(10,11)12;;;;/h6H,1-3,5H2,(H2,7,8,9)(H2,10,11,12);;3*1H2/q;+1;;;/p-1
InChIKey: DCSBSVSZJRSITC-UHFFFAOYSA-M
Product Category of 2-Chloro-5-nitroanisole (CAS NO.1009-36-5): Miscellaneous Biochemicals;Osteoporosis;Inhibitors;Intermediates & Fine Chemicals;Pharmaceuticals;Miscellaneous Compounds

 Alendronate sodium (CAS NO.121268-17-5)  is a bisphosphonate drug used for osteoporosis and several other bone diseases. And it used for prophylaxis and in treatment of female and male osteoporosis. It has been used for prevention and treatment of corticosteroid-associated osteoporosis together with supplements of calcium and vitamin D, and used for paget's disease.

A poison by intravenous route. Experimental reproductive effects. When heated to decomposition it emits toxic vapors of NO_x, PO_x, and NaO.
Hazard Codes: Xn,Xi
The Risk Statements:
22:  Harmful if swallowed 
36/37/38:  Irritating to eyes, respiratory system and skin
The Safety Statements:
26:  In case of contact with eyes, rinse immediately with plenty of water and seek medical advice 
36:  Wear suitable protective clothing  
WGK Germany: 3

 Alendronate sodium , its cas register number is 121268-17-5. It also can be called Fosamax ; Monosodium alendronate ; Alendronic acid monosodium salt ; Fosalan ; Alendros ; Bifosa ; NeoBon ; 4-Amino-1-hydroxybutylidene-1,1-bisphosphonic acid monosodium salt ; and Osteovan . It is marketed alone as well as in combination with vitamin D, and Merck's U.S. patent on alendronate expired in 2008 and Merck lost a series of appeals to block a generic version of the drug from being certified by the U.S. Food and Drug Administration (FDA). Alendronate inhibits osteoclast-mediated bone-resorption.