ABSTRACT
The purity of 4,4′-dimethoxy-5,6,5′,6′-bis (methylenedioxy)-2′-morpholine methylenebiphenyl-2-methyl formate methanesulfonate (IMH), a new drug for fatty liver treatment, was determined through differential scanning calorimetry (DSC). Analysis of two-factor non repeatability method was performed in the investigation the effects of two factors (heating rate and sample weight) on purity determination. The DSC experimental parameters were optimized as follows: heating rate was 10 ℃·min-1, temperature range was 150-300 ℃, sample weight was 2.0-4.1 mg, and N2 flow rate was 80 mL·min-1. The linear correlation coefficient (r) of this DSC method was 0.999 8. The RSD value (n = 6) of precision was 0.03%. The standard value and uncertainty of the purity results of the multiple batches of IMH drugs were (99.74 ± 0.29)%, (99.91 ± 0.28)%, (99.90 ± 0.28)%, and (99.81 ± 0.28)% with inclusion factor (K) of 2 and confidence probability (P) of 0.95. The results were basically consistent with the results of the mass balance method. The DSC mehod is a simple, rapid and accurate method, and provides a new reference method for determining the purity of IMH drugs, improves the accuracy and reliability of purity determination.
ABSTRACT
Compared with other drug-resistant strains, Acinetobacter baumannii has the characteristics of serious drug resistance, high mortality and difficulty to treat. As the phenomena of resistance to existing anti-Acinetobacter baumannii drugs continuously occurs, the development of new anti-Acinetobacter baumannii drugs is urgent. This review introduces the clinical application and research progress of anti-Acinetobacter baumannii drugs, aiming to provide help for the research and development of anti-Acinetobacter baumannii drugs.
ABSTRACT
Lefamulin (BC-3781) is a semi-synthetic pleuromutilin antibiotic, approved for the treatment of community-acquired bacterial pneumonia (CABP) by Food and Drug Administration (USA) in August 2019, with the commodity name of Xenleta. It is the first pleuromutilin antibiotics used for systemic treatment of bacterial infections in human. Lefamulin binds to the peptidyl transferase center of the 50S ribosomal subunit to prevent peptide transfer, thus inhibits protein synthesis. Lefamulin displays expanded activity against gram-positive organisms, and also shows high activity against atypical microorganism like Mycoplasma pneumoniae. This review discusses the mechanism, bacterial spectrum of activity, preclinical and clinical data of Lefamulin.