The invention provides compounds, or a salt or crystalline form of the compounds. A structure of the compounds is represented by a formula I shown in the specification. The compounds provided by the invention are novel-structural puerarin derivatives and are easily soluble in water, wherein the solubility of the compounds in the water is 100 times that of puerarin; and the compounds have obvious anti-hypoxia activity and effect better than that of the puerarin, can be clinically and widely used for preparing medicines for preventing and/or treating cardiovascular and cerebrovascular diseases and diseases such as diabetes, hypertension, cerebral infarction, viral myocarditis and glaucoma.