The Synthesis of Beclomethasone Dipropionate by Chemical Reaction and Microbial Biotransformation
|Keywords||Dual beclomethasone dipropionate Chemical synthesis Microbial transformation Absidia Arthrobacter simplex PSO Aqueous suspension feeding mode Sodium cellulose sulfate (NaCS) / poly diallyl dimethyl ammonium chloride (PDMDAAC) microcapsules immobilized|
Dual beclomethasone dipropionate (beclomethasone dipropionate), ie, 9α-chloro-11β, 17α, 21 - trihydroxy-16β-methyl - progesterone -1,4 - diene-3 ,20 - dione -17,21 - dipropionate, is a new generation of synthetic glucocorticoids, local anti-inflammatory effect is significant, effect on vascular contraction, can be used for the treatment of asthma, dermatitis and allergic rhinitis. Because the dual beclomethasone selectively acting on the respiratory organ tissue, affecting the transcription of target genes specific aspects, so its aerosol formulations in the control and treatment of asthma, rhinitis than the oral medication is more effective and more economical. Currently, the domestic production of the aerosol many manufacturers, and pharmaceutical raw materials, but only a small part of the domestic production. Therefore, developing a low-cost, high yield, simple and green dual beclomethasone dipropionate synthesis route has significant social and economic benefits. In this paper, microbial transformation and chemical synthesis designed one pair of beclomethasone dipropionate synthesis process route. Epoxy progesterone as raw material, after 11 - hydroxylation, 1,2 - dehydrogenation step microbiological method and introducing 16β-methyl and 17α-, 21 - hydroxy-21 - propionate group, 9,11 - double button 17 - propionate ester group, and 9α-chloro and 11β-hydroxy-five-step chemical synthesis process and, ultimately, the content of 99.7% bis beclomethasone dipropionate, and the product was 30% overall yield. Firstly, the use of combined UV-β ray mutagenesis, yielding a blue screened plow mold (Absidia coerulea) AB04-12, for 11 - hydroxylated microbial conversion. In the conversion process, the optimization of 11 - hydroxylation feeding mode bioconversion and fermentation processes. By comparison, methanol, ethanol, 1,2 - propylene glycol and N, N-dimethylformamide was suspended four solvents conversion of feed size, determine the 1,2 - propanediol is an organic solvent suspension feeding mode of the best solvents. Further study of the novel aqueous suspension feeding mode, the particle size of 0.84μm substrate, and water, β-cyclodextrin, and traces of ethanol Tween 80, the ultrasonic oscillation to form a suspension, the direct feed, the 10g / L feed concentration conversion rate increased to about 70%. Multi-layer neural network prequel (MFNN) and particle swarm optimization (PSO) and the aqueous suspension medium optimized feed additive ratio, to get the optimum concentration of glucose added 15.58g / L, corn syrup 27.02g / L, yeast extract 3.47g / L, ammonium sulfate, 10.72g / L, magnesium sulfate 0.62g / L, Tween 80 0.68g / L, β-cyclodextrin 10.00g / L, penicillin 0.04g / L. Proven flask 11 - hydroxylation process 10g / L concentration of the feed conversion rate of 87.5%. Optimal conditions and the above-described aqueous feed suspension for a 3.7L fermenter Absidia 11 - hydroxylation of catalytic processes, 20g / L of substrate feed concentration to achieve the conversion was still 86.6%, a further enlarged potential. This paper also conducted a preliminary cell-catalyzed exploration, discovery hydroxylase catalytic effect after the lysing declined significantly, resulting mostly byproducts. Secondly, in 11 - hydroxylation products Arthrobacter simplex 1,2 - dehydrogenation process, the use of multi-layer neural network and the prequel particle swarm optimization for the training process, get the best medium ratio: Glucose 6.89g / L , corn syrup 9.48g / L, peptone, 1.74g / L, potassium dihydrogen phosphate 2.69g / L. In the conversion process, the effects of feeding time, feeding batches of liquid handling and feed concentration on the dehydrogenation conversion rate. The results showed that one-time feeding, simple operation, small chance of contamination, 28h after inoculation feeding is most appropriate; while the multi-batch feeding can induce dehydrogenase produce than a slightly higher feed conversion rate, especially in 26h, 32h secondary feeding better; organic solvent suspension cast compound, ethanol best; the use of a water suspension feeding can be 25g / L concentration of substrate conversion rate to 91%. This paper also examines the cellulose sulfate initially (NaCS) / poly diallyl dimethyl ammonium chloride (PDMDAAC) microcapsules immobilized Arthrobacter simplex transformation situation. Arthrobacter a simple feeding culture to meet standards embedded in microcapsules in the medium can be used after activation 4h biotransformation. The free culture is different, immobilized microbial conversion system, the organic solvent suspension feeding mode is better than aqueous suspension feeding mode, in the low substrate concentration conversion rate of 90%. NaCS / PDMDAAC weakened microcapsules presence of organic solvents on the growth of Arthrobacter simplex adverse effects of immobilized cells in organic / aqueous two-phase conversion is better than a two-phase conversion of free cells. Third, the use of trimethylchlorosilane and methyl magnesium bromide Grignard reagent reaction, then added m-chloroperbenzoic acid, using the intermediate product of the rearrangement process, the dual hydroxylation, continuously introducing the 16β-methyl group, 17α-hydroxy-and 21 - hydroxy, reducing the reaction steps and by-products, the reaction with high regioselectivity, the total yield of the product stability of 81%. Then, the reaction of propionic anhydride 21 - propionate. The reaction is simple, high yield of 87%. Next, the use of triethylamine and ethyl chloroformate to eliminate the raw material mixture, to give 9,11 - double bond, to avoid the traditional processes in the 11,12 - double bond of the product generation process, the resultant product of high purity, which isomeric byproduct content does not exceed 2% of the product after recrystallization content reaches 98%, the yield was 84%. Then, p-toluenesulfonic acid as a catalyst, the less reactive hydroxyl groups of 17α-propionyl reaction yield was 85%. Finally, the use of N-chlorosuccinimide (NCS) in a nitrogen atmosphere, was synthesized with a 9α-chloro and 11β-hydroxy group of the product, i.e. the final product bis beclomethasone dipropionate, the yield was 90%.