Synthesis method for high-purity selamectin

Abstract

The invention provides a synthesis method for high-purity selamectin. The synthesis method comprises the following steps: with doramectin as a raw material, subjecting the doramectin to hydrogenation,oxidation, oximation and desugaring so as to obtain a crude selamectin product, wherein an oxidation system adopted by oxidation is a manganese dioxide / Dess Martin oxidant or manganese dioxide / 2-iodoylbenzoic acid. According to the invention, the use of a traditional single oxidant is broken through; the manganese dioxide / Dess Martin oxidant or the manganese dioxide / 2-iodoxybenzoic acid is selected as the oxidation system; the oxidation system is mild and controllable; oxidation reaction is more thorough; reaction byproducts are few; thus, the obtained crude selamectin product is high in purity, and conditions are provided for abandoning a C18 high-pressure preparation process in a subsequent refining process. Generally speaking, the synthesis method provided by the invention is short insynthetic route, not tedious in post-treatment process and low in cost, can obtain the selamectin with a purity of 99% or above, and has high total yield.

Description

technical field [0001] The invention relates to the technical field of synthetic pharmacy, in particular to a method for synthesizing high-purity selamectin. Background technique [0002] Selamectin is a new generation of abamectin antiparasitic drug produced by the fermentation of Streptomyces avermitilis. On the 13th, it was approved for marketing by the European Medicines Evaluation Committee (EMEA) and the US Food and Drug Commission (FDA). It was first listed in the UK in July 1999, with the trade name Revolution. It is an internal and external insecticide mainly targeting adult fleas, filarial worms and mange of pet cats and dogs. It has high safety and has good effects when taken orally or injected. [0003] The chemical structural formula of selamectin is as follows: [0004] [0005] The basic patent process route of selamectin is as follows: starting from doramectin, the hydrogenation intermediate is prepared by using Wilkinson catalyst and toluene as solvent ...

AI Technical Summary

Problems solved by technology

However, the overall yield of this process is not high, and each intermediate needs to be separated by silica gel chromatography, and the crude selamectin obtained at last needs to be purified by silica gel column chromatography and high pressure liquid chromatography. The whole process is very unfavorable for industrial production

[0006] Afterwards, there were also reports on improved selamectin synthesis methods, but there were still low purity selamectin crude products, and the final step still needed reversed-phase C18 silica gel column purification or multiple recrystallizations, resulting in a high yield of the entire route. lower, higher cost

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