Abstract: An isoflavone derivative is provided. The isoxazole derivative has following formula: wherein R1 and R2, independently, include C1-C12 alkyl optionally substituted with oxirane, thiirane, aziridine, amino, cycloamino, aminohydroxy or cycloaminohydroxy, and R3 includes hydrogen, hydroxy or C1-C12 alkoxy optionally substituted with oxirane, thiirane, aziridine, amino, cycloamino, aminohydroxy or cycloaminohydroxy. The invention also provides a pharmaceutical composition for treatment of osteoporosis including an isoflavone derivative or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier.