阅读说明：本技术 一种异烟酰胺的制备方法 (Preparation method of isonicotinamide ) 是由 龙华 李自云 邵树强 于 2019-12-02 设计创作，主要内容包括：本发明涉及药物化学技术领域,尤其是一种异烟酰胺的制备方法。该种异烟酰胺的制备方法,以固体斜面上保存的丙酸棒杆菌Corynebacteriumpropinquum为出发菌株,经过发酵、膜过滤、水合反应、再过滤、浓缩、干燥、包装的工艺生产异烟酰胺。本发明的一种异烟酰胺的制备方法采用微生物酶催化生产异烟酰胺,具有反应条件温和、选择性好、流程简单、产物产率和纯度高、成本低、环境污染小等优点,生产过程产生的废物少,进一步降低了生产成本,特别适合大规模生产。(The invention relates to the technical field of medicinal chemistry, in particular to a preparation method of isonicotinamide. The preparation method of the isonicotinamide takes corynebacterium propionicum propinquum stored on a solid inclined plane as an original strain, and produces the isonicotinamide through the processes of fermentation, membrane filtration, hydration reaction, refiltering, concentration, drying and packaging. The preparation method of isonicotinamide adopts microbial enzyme to catalyze and produce isonicotinamide, has the advantages of mild reaction condition, good selectivity, simple process, high product yield and purity, low cost, small environmental pollution and the like, generates less waste in the production process, further reduces the production cost, and is particularly suitable for large-scale production.)

1. A preparation method of isonicotinamide is characterized in that: the method comprises the following steps:

(1) fermentation: fermenting by taking corynebacterium propionicum propinquum stored on a solid inclined plane as a starting strain, and adding a fermentation culture medium into a fermentation tank, wherein the fermentation culture medium mainly comprises the following raw materials in percentage by mass: 0.5-3.0% of glucose, 0.2-0.5% of yeast extract, 0.03-0.08% of magnesium sulfate, 0.45-0.95% of urea and 0.45-0.95% of KH₂P0₄、0.45-0.95%K₂HPO₄、0.0001-0.001%FeCl₃Adjusting pH to 6.5-7.5, sterilizing with inoculation amount of 8-12%, continuously introducing sterile air at 20-30 deg.C, maintaining tank pressure, and culturing for 50-65 hr; stopping fermentation when the biomass reaches 5-12% and the enzyme activity reaches 300-;

(2) membrane filtration: adding deionized water with 2 times of the volume of the fermentation liquor into the fermentation liquor after fermentation for cleaning, filtering nitrile hydratase strain cells by using a membrane machine, and adding soft water into the filtrate to the initial volume of the fermentation liquor;

(3) hydration reaction: adding the filtrate added with the soft water into a reaction kettle, controlling the reaction temperature to be 20-50 ℃, slowly adding the 4-cyanopyridine for reaction, adjusting the adding amount according to the reaction temperature and chromatographic analysis of the residual amount of the 4-cyanopyridine, detecting that the residual amount of the 4-cyanopyridine is less than 150ppm when the reaction is finished, and finishing the reaction, wherein the conversion rate of the hydration reaction is more than 99.9%;

(4) and (3) re-filtering: filtering the reaction solution by a reaction liquid membrane machine to obtain filtrate and filter residue, wherein the main component of the filtrate is isonicotinamide aqueous solution, and the main component of the filter residue is hydrolyzed waste cells and trace 3-cyanopyridine;

(5) concentration: adding the reacted solution into an evaporator, and heating by using steam for concentration to obtain an isonicotinamide solution with the concentration of 50-90%;

(6) and (3) drying: pressing 50-90% isonicotinamide solution into a drying tower by a high-pressure pump for atomization and drying, evaporating water, granulating, further drying by a fluidized bed, and finally feeding the obtained granular isonicotinamide into a storage bin;

(7) packaging: the isonicotinamide in the storage bin is slowly and continuously put to a packing machine by using a control valve, and the isonicotinamide is automatically fed to a feed opening after passing through a vibrating screen, magnetic separation and metal detection in sequence, weighed, vacuumized, sealed in a heat seal manner, labeled and finally stacked to enter a finished product warehouse.

2. The method for preparing isonicotinamide according to claim 1, characterized in that: in the step (1), the fermentation medium mainly comprises the following raw materials in percentage by mass: 0.75% glucose, 0.3% yeast extract, 0.07% magnesium sulfate, 0.55% urea, 0.6% KH₂P0₄、0.45%K₂HPO₄、0.0005%FeCl₃And the balance of water.

3. The method for preparing isonicotinamide according to claim 1, characterized in that: and (3) in the membrane filtration process in the step (4), the method for separating the reacted waste cells from the nitrile hydratase producing bacteria and the trace 3-cyanopyridine comprises the steps of adding the filter residue into the reaction kettle again for further reaction, carrying out membrane filtration, circulating for many times, generating no new isonicotinamide, and adding the filter residue into an incinerator for incineration.

Technical Field

The invention relates to the technical field of medicinal chemistry, in particular to a preparation method of isonicotinamide.

Background

Isonicotinamide, also known as 4-pyridinecarboxamide, is an important pharmaceutical intermediate. Isonicotinamide is a second-line antitubercular drug.

At present, the method for synthesizing isonicotinamide mainly adopts an alkaline hydrolysis method, wherein 4-cyanopyridine reacts with alkali, and the addition amount and reaction temperature of the alkali are controlled by a reaction process to obtain isonicotinamide. The method has low reaction selectivity and side reaction can occur in the reaction process. The isonicotinamide is produced by adopting microbial enzyme catalysis, has the advantages of mild reaction conditions, good selectivity, simple process, high product yield and purity, low cost, small environmental pollution and the like, generates less waste in the production process, further reduces the production cost, and is particularly suitable for large-scale production. Praven KumarMehta et al used Geobacillus subterraneus amidase to biotransform isonicotinamide to synthesize isonicotinic acid (Process Biochemistry, 2015,50(9): 1400-1404). However, no literature report on the production of isonicotinamide from 4-cyanopyridine by using nitrile hydratase is found at present, so that the research has good theoretical significance and practical value.

Disclosure of Invention

The invention aims to provide a preparation method of isonicotinamide, which overcomes the defects of the prior art, adopts microbial enzyme to catalyze and produce isonicotinamide, and has the advantages of mild reaction conditions, good selectivity, simple process, high product yield and purity, low cost and little environmental pollution.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a preparation method of isonicotinamide comprises the following steps:

(1) fermentation: fermenting by taking corynebacterium propionicum propinquum stored on a solid inclined plane as a starting strain, and adding a fermentation culture medium into a fermentation tank, wherein the fermentation culture medium mainly comprises the following raw materials in percentage by mass: 0.5-3.0% of glucose, 0.2-0.5% of yeast extract, 0.03-0.08% of magnesium sulfate, 0.45-0.95% of urea, 0.45-0.95% of KH2P04, 0.45-0.95% of K2HPO4, 0.0001-0.001% of FeCl3 and the balance of water, adjusting the pH to 6.5-7.5, sterilizing, continuously introducing sterile air at the temperature of 20-30 ℃, maintaining the tank pressure, and culturing for 50-65 hours; stopping fermentation when the biomass reaches 5-12% and the enzyme activity reaches 300-;

(2) membrane filtration: adding deionized water with 2 times of the volume of the fermentation liquor into the fermentation liquor after fermentation for cleaning, filtering nitrile hydratase strain cells by using a membrane machine, and adding soft water into the filtrate to the initial volume of the fermentation liquor;

(3) hydration reaction: adding the filtrate into a reaction kettle, controlling the reaction temperature to be 20-50 ℃, slowly adding 4-cyanopyridine for reaction, adjusting the adding amount according to the reaction temperature and the residual amount of the 4-cyanopyridine in chromatographic analysis, and controlling the conversion rate of hydration reaction to be more than 99.9%;

(4) and (3) re-filtering: filtering the reaction solution by a reaction liquid membrane machine to obtain filtrate and filter residue, wherein the main component of the filtrate is isonicotinamide aqueous solution, and the main component of the filter residue is hydrolyzed waste cells and trace 3-cyanopyridine;

(5) concentration: adding the reacted solution into an evaporator, and heating by using steam for concentration to obtain an isonicotinamide solution with the concentration of 50-90%;

(6) and (3) drying: pressing 50-90% isonicotinamide solution into a drying tower by a high-pressure pump for atomization and drying, evaporating water, granulating, further drying by a fluidized bed, and finally feeding the obtained granular isonicotinamide into a storage bin;

(7) packaging: the isonicotinamide in the storage bin is slowly and continuously put to a packing machine by using a control valve, and the isonicotinamide is automatically fed to a feed opening after passing through a vibrating screen, magnetic separation and metal detection in sequence, weighed, vacuumized, sealed in a heat seal manner, labeled and finally stacked to enter a finished product warehouse.

Preferably, in the step (1), the fermentation medium mainly comprises the following raw materials by mass percent: 0.75% glucose, 0.3% yeast extract, 0.07% magnesium sulfate, 0.55% urea, 0.6% KH2P04, 0.45% K2HPO4, 0.0005% FeCl3, and the balance water.

Preferably, in the step (4), the method for separating the waste cells after the reaction from the nitrile hydratase producing bacteria and the trace amount of 3-cyanopyridine in the membrane filtration step is to add the filter residue into the reaction kettle again for further reaction and perform membrane filtration, so that no new isonicotinamide is generated after the cycle is repeated for many times, and the filter residue is added into an incinerator for incineration.

The invention has the beneficial effects that: compared with the prior art, the preparation method of isonicotinamide has the following advantages: the isonicotinamide is produced by adopting microbial enzyme catalysis, has the advantages of mild reaction conditions, good selectivity, simple process, high product yield and purity, low cost, small environmental pollution and the like, generates less waste in the production process, further reduces the production cost, and is particularly suitable for large-scale production.

Detailed Description