Accelerated Hydrolysis of Aspirin Using Alternating Magnetic Fields

The major problem of current drug-based therapy is selectivity. As in other areas of science, a combined approach might improve the situation decisively. The idea is to use the pro-drug principle together with an alternating magnetic field as physical stimulus, which can be applied in a spatially and temporarily controlled manner. As a proof of principle, the neutral hydrolysis of aspirin in physiological phosphate buffer of pH 7.5 at 40 °C was chosen. The sensor and actuator system is a commercially available gold nanoparticle (NP) suspension which is approved for animal usage, stable in high concentrations and reproducibly available. Applying the alternating magnetic field of a conventional NMR magnet system accelerated the hydrolysis of aspirin in solution

Determining the Absolute Configuration of (+)-Mefloquine HCl, the Side-Effect-Reducing Enantiomer of the Antimalaria Drug Lariam

Even though the important antimalaria drug <i>rac</i>-<i>erythro</i>-mefloquine HCl has been on the market as Lariam for decades, the absolute configurations of its enantiomers have not been determined conclusively. This is needed, since the (−) enantiomer is believed to cause adverse side effects in malaria treatment resulting from binding to the adenosine receptor in the human brain. Since there are conflicting assignments based on enantioselective synthesis and anomalous X-ray diffraction, we determined the absolute configuration using a combination of NMR, optical rotatory dispersion (ORD), and circular dichroism (CD) spectroscopy together with density functional theory calculations. First, structural models of <i>erythro</i>-mefloquine HCl compatible with NMR-derived ³<i>J</i>_HH scalar couplings, ¹⁵N chemical shifts, rotational Overhauser effects, and residual dipolar couplings were constructed. Second, we calculated ORD and CD spectra of the structural models and compared the calculated data with the experimental values. The experimental results for (−)-<i>erythro</i>-mefloquine HCl matched our calculated chiroptical data for the 11<i>R</i>,12<i>S</i> model. Accordingly, we conclude that the assignment of 11<i>R</i>,12<i>S</i> to (−)-<i>erythro</i>-mefloquine HCl is correct