Abstract: Provided is a method for preparing apremilast of formula I. Method one: (S)-1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethylamine N-acetyl-L-leucine salt of formula II is reacted with 3-acetylaminophthalic anhydride of formula III in an aprotic solvent to produce the compound of formula I; method two: (S)-1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethylamine N-acetyl-L-leucine salt of formula II is reacted with 3-acetylaminophthalic anhydride of formula III in an organic solvent in the presence of an organic alkali or an alkali metal hydride to produce the compound of formula I. The method for preparing apremilast requires inexpensive raw materials and reagents, is suitable for industrial production, and has great economic effects.

Abstract: Provided is a synthesis method for a voriconazole intermediate condensate as shown in formula II or an acid addition salt thereof. As shown in reaction formula 1, the product is prepared via compounds III and IV. The synthesis method adjusts the feeding means, and the reaction conditions are mild and controllable, thereby reducing the production of impurity A, avoiding the use of highly toxic metal lead, and eliminating the risk of highly toxic metal remaining in a drug. The product has a higher purity and significant industrial application value.

Abstract: Provided is a method for preparing apremilast of formula I. Method one: (S)-1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethylamine N-acetyl-L-leucine salt of formula II is reacted with 3-acetylaminophthalic anhydride of formula III in an aprotic solvent to produce the compound of formula I; method two: (S)-1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethylamine N-acetyl-L-leucine salt of formula II is reacted with 3-acetylaminophthalic anhydride of formula III in an organic solvent in the presence of an organic alkali or an alkali metal hydride to produce the compound of formula I. The method for preparing apremilast requires inexpensive raw materials and reagents, is suitable for industrial production, and has great economic effects.

Abstract: Provided is a synthesis method for a voriconazole intermediate condensate as shown in formula II or an acid addition salt thereof. As shown in reaction formula 1, the product is prepared via compounds III and IV. The synthesis method adjusts the feeding means, and the reaction conditions are mild and controllable, thereby reducing the production of impurity A, avoiding the use of highly toxic metal lead, and eliminating the risk of highly toxic metal remaining in a drug. The product has a higher purity and significant industrial application value.