ABSTRACT
Objective: To optimize the synthesis process of 1-(4-aminophenyl)-5, 6-dihydro-3-(4-orpholinyl)-2(1H)-pyridinone.Methods: Using p-nitroaniline as the raw material, the target compound was obtained by amidation, cyclization, chlorination, nitration and reduction reactions. The sodium hydride catalyst for cyclization was taken out in the reaction, the reaction acid binding agent was improved, the reaction temperature of intermediate was reduced, the optimal ratio and reaction ratio condition were investigated, and the post-processing conditions were optimized for each reaction. Results: The target compound was confirmed by 1H NMR and 13C NMR data, and the total yield was 65.4%. Conclusion: The optimized process is simple to operate, mild and controllable, and the solvent is easy to recycle, low-polluting and more conducive to industrial production.
ABSTRACT
<p><b>AIM</b>To establish an efficient method for preparation of solid lipid nanoparticles with high recovery.</p><p><b>METHODS</b>Monostearin solid lipid nanoparticles was prepared by solvent diffusion method in aqueous system. The recovery of the method was greatly improved by adjusting the Zeta potential.</p><p><b>RESULTS</b>The drug-loaded solid lipid nanoparticles suspension was quickly produced and easily separated with centrifugation at 4,000 r.min-1 under acidic condition. Compared with the nanoparticles made without adjusting the Zeta potential, the recovery of nanoparticles prepared in this way was significantly increased. The release behavior in vitro showed an initial burst effect in the first 3 hours followed by a slower rate stage of 4 days with nearly 6% drug released in each day.</p><p><b>CONCLUSION</b>The solvent diffusion method in aqueous system might be used as a new method to prepare solid lipid nanoparticles in the future. The loaded drug can be released in a controlled manner.</p>