The Production Process of (+)-Lansoprazole

Introduction:
Lansoprazole is a widely used proton pump inhibitor drug for the treatment of acid-related diseases.
It is an important pharmaceutical product with a high demand in the market, and the production process of (+)-lansoprazole requires strict quality control and attention to detail to ensure the purity and efficacy of the drug.
In this article, we will discuss the production process of (+)-lansoprazole, including the raw material preparation, chemical reactions, purification, and quality control steps.

Raw Material Preparation:
The production of lansoprazole begins with the preparation of raw materials, which includes the stereoisomer (S)-2-[[[3-Methyl-4-(2,4,9-triméthyl-1,3-oxaida ndraz-2-yl)-1H-pyrazol-1-yl]methyl]sulphonyl]amide.
The precursor to this raw material is the amino acid tryptophan, which is synthesized through a multi-step process that involves the biosynthesis of its precursor, chorismate, followed by modifications such as the Sharpless epoxidation and the WACKER oxidation.

Chemical Reactions:
The raw materials are then subjected to various chemical reactions to produce lansoprazole.
The first step involves the reaction of the amino acid tryptophan with excess p-toluenesulfonyl chloride in the presence of a solvent such as benzene or chloroform.
This reaction leads to the formation of N-p-toluenesulphonyl-L-tryptophan.

The N-p-toluenesulphonyl-L-tryptophan is then converted into N-p-toluenesulphonyl-L-tyrosine through a series of reactions that involve the hydrolysis of the intermediate N-p-toluenesulphonyl-L-dipeptide and the oxidation of N-p-toluenesulphonyl-L-tyrosine.

The N-p-toluenesulphonyl-L-tyrosine is then treated with hydrogen chloride gas in the presence of a catalyst such as palladium on barium sulfate to form N-p-toluenesulphonyl-L-3,4-dihydroxybenzaldehyde.

The N-p-toluenesulphonyl-L-3,4-dihydroxybenzaldehyde is then subjected to the Knöfeldt reaction, where it is treated with sodium hydroxide and dimethyl sulfate in the presence of a solvent such as acetonitrile, to form N-p-toluenesulphonyl-L-3,4-dihydroxybenzyl alcohol.

The N-p-toluenesulphonyl-L-3,4-dihydroxybenzyl alcohol is then treated with sodium hydroxide in the presence of water to form N-p-toluenesulphonyl-L-3,4-dihydroxybenzylamine.

The N-p-toluenesulphonyl-L-3,4-dihydroxybenzylamine is then treated with hydrochloric acid in the presence of a solvent such as ethanol to form N-p-toluenesulphonyl-L-3,4-dihydroxybenzamide.

The N-p-toluenesulphonyl-L-3,4-dihydroxybenzamide is then treated with a strong base such as sodium hydroxide in the presence of water to form N-p-toluenesulphonyl-L-3,4-dihydroxybenzene sulfonamide.

The N-p-toluenesul