Abstract: The present disclosure provides a compressor rotor, a compressor and a refrigerant circulation system. The compressor rotor includes: a motor rotor including a plurality of rotor sections, a locking rod, a compression unit rotating part and a locking member. The rotor sections are fixedly connected in an axial direction and are provided with an axial through hole and the locking rod penetrates through the axial through hole. The compression unit rotating part is located at the end part of the motor rotor and is connected to the locking rod. The locking member is configured to lock the compression unit rotating part on the locking rod. The locking rod, the compression unit rotating part and the locking member form a pressing structure which applies a pressure toward an axial inner side to the motor rotor.

Abstract: A synthesis method for selamectin was developed, where doramectin is oxidized by manganese dioxide, oximated and de-sugared in one-step by an aqueous solution of hydroxylamine hydrochloride, and then selectively reduced in the presence of Wilkinson's catalyst and hydrogen to obtain selamectin. Doramectin is oxidized to a carbonyl group firstly, so that the generation of impurities during the subsequent reaction is reduced; t-butyl alcohol with a larger steric hindrance is used as a solvent, so that transesterification impurities are avoided; the hydrogenation is implemented in the final step, and the crude product is recrystallized before the hydrogenation reaction, so that the cost is greatly reduced. The method of the present application with an overall yield of 57%. The purity of product was 97.11%. All impurities meet the requirements of Pharmacopoeia. The present application is a simpler, more economical and more efficient synthesis method, and is suitable for industrial production.

Abstract: The present application provides the preparation and use of a 3,4-dihydroxyl-N-(1?-benzyl-2?-hydroxyethyl)-2-methyl pyridine chloride. According to the present application, a 3,4-dihydroxyl-N-(1?-benzyl-2?-hydroxyethyl)-2-methyl pyridine chloride is directly synthesized by a one-step reaction, and the compound includes a pharmaceutically acceptable salt thereof. 3,4-dihydroxyl-N-(1?-benzyl-2?-hydroxyethyl)-2-methyl pyridine chloride has been proved to have a good antiparkinsonian activity by animal tests, and it is a class of novel antiparkinsonian drug candidates.

Abstract: Disclosed are as represented by Formula (I) a quinazoline derivative and a pharmaceutical acceptable salt thereof, or, an enantiomer, a non-enantiomer, a tautomer, a racemate, a solvate, a metabolic precursor, or a prodrug of both. Also disclosed are a preparation method therefor, an intermediate, a pharmaceutical composition having the quinazoline derivative, and an application thereof. The quinazoline derivative of the present invention is provided with improved anti-tumor activity.

Abstract: Disclosed are as represented by Formula (I) a quinazoline derivative and a pharmaceutical acceptable salt thereof, or, an enantiomer, a non-enantiomer, a tautomer, a racemate, a solvate, a metabolic precursor, or a prodrug of both. Also disclosed are a preparation method therefor, an intermediate, a pharmaceutical composition having the quinazoline derivative, and an application thereof. The quinazoline derivative of the present invention is provided with improved anti-tumor activity.