Ulrike Holzgrabe

Summary

Country: Germany

Publications

  1. Messerer R, Dallanoce C, Matera C, Wehle S, Flammini L, Chirinda B, et al. Novel bipharmacophoric inhibitors of the cholinesterases with affinity to the muscarinic receptors M1 and M2. Medchemcomm. 2017;8:1346-1359 pubmed publisher
    ..Since 10-C10 showed almost no cytotoxicity, it emerged as a promising lead structure for the development of an anti-Alzheimer drug. ..
  2. Berninger M, Schmidt I, Ponte Sucre A, Holzgrabe U. Novel lead compounds in pre-clinical development against African sleeping sickness. Medchemcomm. 2017;8:1872-1890 pubmed publisher
    ..Of note, it may turn out to be difficult to confirm in vitro activity in an animal model of infection; however, possible reasons for the missing efficacy in unsuccessful in vivo studies are discussed. ..
  3. El Hossary E, Förstner K, Francois P, Baud D, Streker K, Schrenzel J, et al. A Novel Mechanism of Inactivating Antibacterial Nitro Compounds in the Human Pathogen Staphylococcus aureus by Overexpression of a NADH-Dependent Flavin Nitroreductase. Antimicrob Agents Chemother. 2018;62: pubmed publisher
    ..Biochemical reactions confirmed an NADH-dependent deactivation of the nitro-substituted compounds. Thus, this is the first report of a nitroreductase-based antibiotic resistance mechanism in the human pathogen S. aureus. ..
  4. Schilling K, Pawellek R, Lovejoy K, Muellner T, Holzgrabe U. Influence of charged aerosol detector instrument settings on the ultra-high-performance liquid chromatography analysis of fatty acids in polysorbate 80. J Chromatogr A. 2018;: pubmed publisher
    ..Overall, this new UHPLC method method offers improved detection limits, as well as time savings of over 75% and eluent savings of more than 40% compared to the previously published HPLC-CAD method for polysorbate analysis. ..
  5. Becht A, Schollmayer C, Wiest J, Heller D, Baumann W, Buschmann H, et al. Diffusion ordered NMR spectroscopy measurements as screening method of potential reactions of API and excipients in drug formulations. J Pharm Biomed Anal. 2018;162:41-46 pubmed publisher
    ..The reaction of 5-ASA with formic acid and benzocaine with dibutyl phthalate was also studied by means of DOSY experiments. ..
  6. Theiss C, Holzgrabe U. Characterization of polydisperse macrogols and macrogol-based excipients via HPLC and charged aerosol detection. J Pharm Biomed Anal. 2018;160:212-221 pubmed publisher
    ..e. macrogol ethers with FAA, macrogol esters with FA, and polysorbates, were successfully analyzed for oligomeric distribution and free precursor molecules in one run. ..
  7. Berninger M, Erk C, Fuß A, Skaf J, Al Momani E, Israel I, et al. Fluorine walk: The impact of fluorine in quinolone amides on their activity against African sleeping sickness. Eur J Med Chem. 2018;152:377-391 pubmed publisher
    ..b. brucei. The ability of the new quinolone amides to cross the BBB was confirmed using an 18F-labelled quinolone amide derivative by means of ex vivo autoradiography of a murine brain. ..
  8. Kühnreich R, Holzgrabe U. Impurity profiling of L-methionine by HPLC on a mixed mode column. J Pharm Biomed Anal. 2016;122:118-25 pubmed publisher
    ..The amount of impurities found in batches was very low. Only L-methionine-sulfoxide and N-acetyl-DL-methionine could be detected in levels less than 0.05%. ..
  9. Schilling K, Amstalden M, Meinel L, Holzgrabe U. Impurity profiling of l-asparagine monohydrate by ion pair chromatography applying low wavelength UV detection. J Pharm Biomed Anal. 2016;131:202-207 pubmed publisher
    ..In contrast to the currently used thin layer chromatographic test, the method is capable of separating and quantitatively assessing expected ninhydrin-positive and -negative impurities from synthetic and enzymatic production pathways. ..

More Information

Publications22

  1. Ilko D, Steiger C, Keller R, Holzgrabe U, Meinel L. Tamper-proof tablets for distinction between counterfeit and originator drugs through PEG coding. Eur J Pharm Biopharm. 2016;99:1-6 pubmed publisher
    ..The approach is limited to cases in which PEGs are not present for formulation purposes as excipients, as coding against this background was unfeasible. ..
  2. Mwalwisi Y, Hoellein L, Kaale E, Holzgrabe U. Development of a simple, rapid, and robust liquid chromatographic method for the simultaneous determination of sulfalene, sulfadoxine, and pyrimethamine in tablets. J Pharm Biomed Anal. 2016;129:558-570 pubmed publisher
  3. Wahl O, Holzgrabe U. Amino acid analysis for pharmacopoeial purposes. Talanta. 2016;154:150-63 pubmed publisher
    ..Production methods and possible impurities as well as separation and detection methods suitable for said impurities are subject to this review. ..
  4. Hiltensperger G, Hecht N, Kaiser M, Rybak J, Hoerst A, Dannenbauer N, et al. Quinolone Amides as Antitrypanosomal Lead Compounds with In Vivo Activity. Antimicrob Agents Chemother. 2016;60:4442-52 pubmed publisher
    ..Spray-dried GHQ168 demonstrated exciting antitrypanosomal efficacy. ..
  5. Unger N, Holzgrabe U. Stability and assessment of amino acids in parenteral nutrition solutions. J Pharm Biomed Anal. 2018;147:125-139 pubmed publisher
    ..This review focuses on amino acid stability in pure amino acid solution and name methods of assessment. Incompatibilities of amino acids with the other ingredients are matter of concern in clinical practice and evaluated for relevance. ..
  6. Skaf J, Hamarsheh O, Berninger M, Balasubramanian S, Oelschlaeger T, Holzgrabe U. Improving anti-trypanosomal activity of alkamides isolated from Achillea fragrantissima. Fitoterapia. 2018;125:191-198 pubmed publisher
    ..1. Toxicity of 26 and 27 was assessed using the greater wax moth Galleria mellonella larvae as an in vivo model. No significant toxicity was observed for the concentration range of 1.25-20mM. ..
  7. Seufert F, Kuhn M, Hein M, Weiwad M, Vivoli M, Norville I, et al. Development, synthesis and structure-activity-relationships of inhibitors of the macrophage infectivity potentiator (Mip) proteins of Legionella pneumophila and Burkholderia pseudomallei. Bioorg Med Chem. 2016;24:5134-5147 pubmed publisher
    ..Synthesis and evaluation of the compounds in PPIase assays resulted in highly active inhibitors. The activities can be interpreted in terms of a common binding mode obtained by docking calculations. ..
  8. Schmidt I, Göllner S, Fuß A, Stich A, Kucharski A, Schirmeister T, et al. Bistacrines as potential antitrypanosomal agents. Bioorg Med Chem. 2017;25:4526-4531 pubmed publisher
    ..In addition, the inhibition of trypanothione reductase by bistacrines was found. This flavoprotein oxidoreductase is the main defense against oxidative stress in the thiol redox system unique for protozoa. ..
  9. Wahl J, Holzgrabe U. Capillary electrophoresis separation of phenethylamine enantiomers using amino acid based ionic liquids. J Pharm Biomed Anal. 2018;148:245-250 pubmed publisher
    ..The best results for the separation of all enantiomers were achieved using 125mmol/L tetrabutylammonium l-argininate in a 75mmol/L phosphate buffer pH 1.5 containing 30mmol/L ?-cyclodextrin. ..
  10. Wahl O, Cleynhens J, Verbruggen A, Holzgrabe U. Impurity profiling of N,N'-ethylenebis-l-cysteine diethyl ester (Bicisate). J Pharm Biomed Anal. 2018;150:132-136 pubmed publisher
    ..A new degradation product of bicisate, bicisate lactam, was identified during sample solution stability assessment. ..
  11. Zilker M, Sorgel F, Holzgrabe U. A stability-study of expired ampoules manufactured more than 40 years ago. J Pharm Biomed Anal. 2018;150:318-326 pubmed publisher
    ..In Suprarenin and Adrenalin in Oil, both containing epinephrine, Impletol (procaine), and Persantin® (dipyridamole) contents were decreased to 70%, 74%, 79%, and 86%, respectively, and therefore out of specification. ..
  12. Schmidt I, Pradel G, Sologub L, Golzmann A, Ngwa C, Kucharski A, et al. Bistacrine derivatives as new potent antimalarials. Bioorg Med Chem. 2016;24:3636-42 pubmed publisher
  13. Schmidt M, Skaf J, Gavril G, Polednik C, Roller J, Kessler M, et al. The influence of Osmunda regalis root extract on head and neck cancer cell proliferation, invasion and gene expression. BMC Complement Altern Med. 2017;17:518 pubmed publisher
    ..Thin layer chromatography identified ferulic acid to be present in the extract. The presented results justify the use of royal fern extracts as an anti-cancer remedy in history and imply a further analysis of ingredients. ..