Zhejiang Tianyu Pharmaceutical Co., Ltd.

Panasonic Motor (hangzhou) Co., Ltd.

Wei Xiao

Zhen Wang

Lei Zhang

Yongjun Tu

Gang Liu

Guorong Zhu

Ruiyun Lv

Zuwei He

Dequan Su

Provided is a preparation method of losartan, which is prepared by reacting a cyano group-containing intermediate represented by formula (I) with an azide reagent in toluene in the presence of a catalyst; wherein, after the reaction is completed, azide ions are removed by means of the following process: adding water to divide the reaction system into three layers, separating the intermediate layer and adding n-butanol to the intermediate layer for dilution, and adding triphenylphosphine to the resulting diluted solution so as to remove residual azide ions from the diluted solution. The preparation method provided by the present invention does not need to use sodium nitrite, thus fundamentally eliminating the formation of genotoxic impurities nitrosamines. The resulting target product has good purity, high yield, a simple preparation process, mild and easy-to-control operating conditions, and good safety, and is suitable for large-scale industrial production,

Preparation method for losartan

A waterproof motor, which includes a stator arranged on a motor housing, a rotor arranged in the motor housing, a rotating shaft connected to the rotor and extending out of the motor housing, and a circuit board arranged in the motor housing. An inner end cap is arranged in the motor housing, between the rotor and the circuit board, which surround the rotating shaft and extends in the radial direction of the rotating shaft.

Waterproof motor

Growing community of inventors

Zhejiang, China

Wei Xiao