A kind of preparation method of rifampicin Ⅱ crystal form

Abstract

The invention discloses a preparation method of a rifampicin II crystal form. The preparation method comprises the following steps: dissolving rifampicin crude materials with the purity being more than or equal to 90% in acetone, wherein the concentration of the solution is as follows: the ratio of rifampicin to acetone is equal to 0.08-0.24g / mL; adding water with the volume being 1-6% of the volume of the acetone, raising the temperature to 50-57 DEG C so as to completely dissolve rifampicin solid; adopting a vacuum evaporative crystallization to evaporate the rifampicin solution, and when the volume of the distilled liquid is 30-50% of the volume of the acetone, ending the evaporation; then adopting cooling crystallization, and reducing the temperature to 0-10 DEG C; and filtering, washing and drying crystal mush to obtain a rifampicin II crystal-form product. The yield in the crystallization process is more than 70%, the purity of crystal is more than 97%, the bulk density is more than 0.7g / mL, the average particle size reach more than 130mu m, and the filtering is easy. The preparation method disclosed by the invention has the advantages that the operation time is short, the seed crystal does not need to be added, the flowability of the product is good, the caking of crystal boards can be avoided, and the filtering time and the drying time are shortened, so that the application prospect is good.

Description

technical field [0001] The invention belongs to the technical field of chemical engineering industrial crystallization, and in particular relates to a preparation method of rifampicin II crystal form. Background technique [0002] Rifampicin, English name: Rifampicin, 3-(4-Methylpiperazinyliminomethyl)rifamycinSV; chemical name 3-[[(4-methyl-1-piperazinyl)imino]methyl]-rifamycin. Alias: Lifuping, Mepirifamycin, Rimidine, Molecular Formula C 43 h 58 N 4 o 12 , molecular weight 822.95, CAS number: 13292-46-1, the chemical structure is shown in the figure below. Rifampicin is bright red or dark red crystalline powder, tasteless and odorless, easily soluble in chloroform, soluble in methanol, almost insoluble in water. [0003] [0004] Rifampicin is an antibacterial drug that has high antibacterial activity against Mycobacterium tuberculosis, and has obvious antibacterial effects on Gram-positive bacteria and negative bacteria such as Neisseria meningitidis, Haemophilus...

AI Technical Summary

Problems solved by technology

This method has the disadvantage of long cooling and crystallization time

[0010] Electron micrographs of commercially available II crystal form rifampicin products are as follows: figure 1 As shown, the particle size of the product is small, and the crushing is serious. Its main particle size is about 70 μm, and its bulk density is 0.5 g / mL. The process method is to stand for a long time to cool and crystallize. poor environment

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