Abstract: A polyethylene glycol derivative compound is represented by Formula 1 described in the detailed description. In Formula 1, n is a natural number of 30 to 115, and R1 and R2 are C1 to C5 alkyl that are identical to or different from each other.

Abstract: The present invention relates to a novel intermediate used for physiologically active polypeptides and a method for preparing the same. The novel intermediate may be effectively used as an intermediate for the preparation of physiologically active polypeptide pharmaceuticals, and may be efficiently used for the preparation of high-quality pharmaceuticals by providing a polypeptide intermediate of high yield and high purity.

Abstract: The present invention relates to an improved method for preparing a high purity polyethylene glycol dialdehyde derivative. The preparation method can provide the polyethylene glycol dialdehyde derivative suitable as a raw material for pharmaceuticals because of high purity and terminal activity, by using PEG-diacetal, which is prepared by reacting polyethyleneglycol methanesulfonate with dialkoxy-1-propanol, as an intermediate.

Abstract: The present invention relates to a polyethylene glycol derivative and a preparation method thereof. A preparation process of a polyethylene glycol derivative, according to the present invention, may provide a novel polyethylene glycol derivative which can be utilized in various ways as a drug linker, and is appropriate and effective for mass production and is advantageous in reproducible mass production of high-quality products.

Abstract: The present invention relates to an improved method for preparing a high purity polyethylene glycol dialdehyde derivative. The preparation method can provide the polyethylene glycol dialdehyde derivative suitable as a raw material for pharmaceuticals because of high purity and terminal activity, by using PEG-diacetal, which is prepared by reacting polyethyleneglycol methanesulfonate with dialkoxy-1-propanol, as an intermediate.

Abstract: The present invention relates to a new, simple, and easy process for preparing cephalosporin antibiotics of the following formula (I), such as ceftazidime and cefixime. The process comprises acylating a 7-amino cephalosporanic acid derivative of the following formula (III) with a crystalline aminothiazole compound of the following formula (II): wherein R1 and R2 are the same or different and independently represent H, a C1-4 alkyl or C3-5 cycloalkyl group, R4 represents acetoxymethyl, methylpyridine, or vinyl, X represents chlorine or bromine, and the acid in the acid addition salt represents an inorganic acid, such as hydrochloric acid, or an organic acid, such as formic acid or acetic acid.

Abstract: The present invention relates to a new crystalline aminothiazole derivative represented by the following formula (I) which is very useful for the preparation of cephalosporin antibiotics, including ceftazidime and cefixime, etc: wherein R1 and R2 are the same or different and independently represent H, an alkyl group of 1 to 4 carbon atoms, or a cycloalkyl group of 3 to 5 carbon atoms, X represents chlorine or bromine, and the acid in the acid addition salt represents an inorganic acid, such as hydrochloric acid, hydrobromic acid, sulfuric acid, or perchloric acid, or an organic acid, such as formic acid, acetic acid, trifluoroacetic acid, propionic acid, methanesulfonic acid, or benzenesulfonic acid.