Abstract: The present invention relates to an improved method of preparing adefovir dipivoxil of Formula 1. The method of the present invention is characterized by using dimethylsulfoxide as a reaction solvent, and comprises a process of preparing adefovir dipivoxil of Formula 1 by allowing adefovir of Formula 2 to react with chloromethylpivalate at a reaction temperature of 30 to 50° C. under the presence of dimethylsulfoxide and triethylamine solvents.

Abstract: Provided is a fast dissolving oral tablet, and a method for the production thereof, including the steps of: compressing a mixture of active ingredients, pharmaceutically acceptable additives, and supercritical fluid-soluble substances to produce the tablets; and allowing the tablets to contact a supercritical fluid to extract supercritical fluid-soluble substances from fine pores in the tablets.

Abstract: The present invention relates to an improved method of preparing adefovir dipivoxil of Formula 1. The method of the present invention is characterized by using dimethylsulfoxide as a reaction solvent, and comprises a process of preparing adefovir dipivoxil of Formula 1 by allowing adefovir of Formula 2 to react with chloromethylpivalate at a reaction temperature of 30 to 50° C. under the presence of dimethylsulfoxide and triethylamine solvents.

Abstract: The present invention relates to a novel method of purifying adefovir dipivoxil of Formula 1. The purification method according to the present invention comprises the steps of dissolving impure adefovir dipivoxil containing byproducts generated during a synthetic reaction, salts thereof or complexes thereof in water or a water-containing mixed solvent; purifying the adefovir dipivoxil solution through a reverse-phase column; and adding a base to the purified adefovir dipivoxil solution and extracting the same with an organic solvent. Further, the present invention provides a method of preparing amorphous adefovir dipivoxil by removing the solvent from the high purity solution of adefovir dipivoxil represented by formula I purified by the above method.

Abstract: The present invention relates to an amorphous solid dispersion with improved stability comprising 9-[2-[[bis[(pivaloyloxy)methyl]phosphono]methoxy]ethyl]adenine as a nucleotide analogue, a pharmaceutical composition comprising the same, and a method for preparing the same.

Abstract: The present invention relates to a process for preparing lovastatin and simvastatin which comprises (1) performing step of a lactonization of mevinic acid and analog thereof compounds in the presence of a dehydrating agent and without an acid catalyst under nitrogen sweep; and then (2) making step of crystals at a high temperature. In the process of the present invention, lovastatin and simvastatin highly purified can be produced in a high yield and especially, heterodimers formed as a by-product can be reduced in an amount remarkably. Therefore, the process of the present invention is convenient and economical.

Abstract: The present invention relates to a process for preparing lovastatin and simvastatin which comprises (1) performing step of a lactonization of mevinic acid and analog thereof compounds in the presence of a dehydrating agent and without an acid catalyst under nitrogen sweep; and then (2) making step of crystals at a high temperature. In the process of the present invention, lovastatin and simvastatin highly purified can be produced in a high yield and especially, heterodimers formed as a by-product can be reduced in an amount remarkably. Therefore, the process of the present invention is convenient and economical.

Abstract: The present invention relates to a process for preparing a cephem derivative represented by the following formula (I): ##STR1## useful as an intermediate for the preparation of antibiotics.