A green procedure for the kinetic resolution of chiral amines via enzymatic acylation and deacylation has been demonstrated. The fully enzymatic approach obviates the common, waste-generating deacylation under strongly alkaline conditions. The acylating agent was (R)-phenylglycine propyl ester in combination with Candida antarctica lipase B as acylation catalyst. The enantiomerically enriched amides were subsequently deacylated in the presence of the penicillin G acylase from Alcaligenes faecalis. The degree of enantiomer recognition by CaLB in the acylation of aliphatic amines was unexpectedly modest, but a considerable further enantiomeric enrichment could be accomplished in the course of the subsequent enzymatic hydrolysis step.
A fully enzymatic methodology for the resolution of chiral amines has been demonstrated. Candida antarctica lipase B (CaLB)-catalyzed acylation with N-methyl-and N-phenylglycine, as well as analogues having the general formula R 1 À X À CH 2 CO 2 R 2 (R 1 = Me, Ph; X = O, S) afforded the corresponding enantioenriched amides, which were subsequently enzymatically hydrolyzed. Surprisingly, CaLB also proved to be the catalyst of choice for this latter step. The heteroatom in the acyl donor profoundly influences both the enzymatic acylation and deacylation; the O-substituted reagents performed best with regard to enantioselectivity as well as reaction rate in synthesis and hydrolysis.
Abstract. Rheumatoid arthritis is the most common autoimmune disease that affects the joints. The cause of the disease is unknown, many studies proposed hypothesis about the etiology of rheumatoid arthritis. The clinical manifestations of arthritis are different in each patients. In addition, the development of the medication is still continue to achieve the most effective role with less side effect. Nanoparticles may be the answer to this problem, since they have been widely used to improve the pharmacokinetic and pharmacodynamics of rheumatoid arthritis drugs. Using nanoparticles-tagged folate or PEG to deliver rheumatoid arthritis drugs may increase the specificity of the drugs to the target and consequently, may decrease the side effects of the drugs. The purpose of this review is to summarize the etiology, clinical manifestation and highlighting the use of nanoparticles in rheumatoid arthritis treatment.
Ribosome-inactivating protein (RIP) from Mirabilis jalapa L. leaves has cytotoxic effects on breast cancer cell lines but is less toxic towards normal cells. However, it can easily be degraded after administration so it needs to be formulated into nanoparticles to increase its resistance to enzymatic degradation. The objectives of this study were to develop a protein extract of M. jalapa L. leaves (RIP-MJ) incorporated into nanoparticles conjugated with Anti-EpCAM antibodies, and to determine its cytotoxicity and selectivity in the T47D breast cancer cell line. RIP-MJ was extracted from red-flowered M. jalapa L. leaves. Nanoparticles were formulated based on polyelectrolyte complexation using low viscosity chitosan and alginate, then chemically conjugated with anti-EpCAM antibody using EDAC based on carbodiimide reaction. RIP-MJ nanoparticles were characterised for the particle size, polydispersity index, zeta potential, particle morphology, and entrapment efficiency. The cytotoxicity of RIP-MJ nanoparticles against T47D and Vero cells was then determined with MTT assay. The optimal formula of RIP-MJ nanoparticles was obtained at the concentration of RIP-MJ, low viscosity chitosan and alginate respectively 0.05%, 1%, and 0.4% (m/v). RIP-MJ nanoparticles are hexagonal with high entrapment efficiency of 98.6%, average size of 130.7 nm, polydispersity index of 0.380 and zeta potential +26.33 mV. The IC 50 values of both anti-EpCAM-conjugated and non-conjugated RIP-MJ nanoparticles for T47D cells (13.3 and 14.9 µg/mL) were lower than for Vero cells (27.8 and 33.6 µg/mL). The IC 50 values of conjugated and nonconjugated RIP-MJ for both cells were much lower than IC 50 values of non-formulated RIP-MJ (>500 µg/mL).
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