Synthesis and biological evaluation of 5,6,7-trimethoxy-1-benzylidene-3,4-dihydro-naphthalen-2-one as tubulin-polymerization inhibitors

A series of new combretastatin-A4 analogs were synthesized, in which a six-membered ring connects the linking bridge and A ring, and their tumor cell growth and tubulin-polymerization inhibitory activity were evaluated. These compounds appear to be potential tubulin-polymerization inhibitors, Compounds 1b with amino substituted on position 3 of B ring conferred optimal bioactivity, higher than that of the lead compound 22b and equivalent to that of CA-4. The binding modes of these compounds to tuhulin were obtained by molecular docking, which can explain the structure-activity relationship. The studies presented here provide a new structural type for the development of novel antitumor agents.

Instantly Investigating the Adsorption of Polymeric Corrosion Inhibitors on Magnesium Alloys by Surface Analysis under Ambient Conditions

Surface engineering of magnesium alloys requires adequate strategies, processes and materials permitting corrosion protection. Liquid formulations containing corrosion inhibitors often are to be optimized according to the demands of the respective substrate and following the service conditions during its application. As an interdisciplinary approach, a combination of several techniques for instantly monitoring or elaborately analyzing the surface state of magnesium was accomplished in order to characterize the performance of new adsorbing sustainable amphiphilic polymers which recently were developed to facilitate a multi-metal corrosion protection approach. The application of established techniques like Contact Angle measurements and X-ray Photoelectron Spectroscopy investigations was supplemented by introducing related and yet faster online-capable and larger-scale techniques like Aerosol Wetting Test and Optically Stimulated Electron Emission. Moreover, an inexpensive setup was configured for scaling the inset and the extent of degradation processes which occur at local electrochemical circuits and lead to hydrogen bubble formation. Using these analytical tools, changes of the surface state of emeried AM50 samples were investigated. Even in contact with water, being a moderate corrosive medium, the online techniques facilitated detecting surface degradation of the unprotected magnesium alloy within some seconds. In contrast, following contact with a 1 weight% formulation of a polymeric corrosion inhibitor, surface monitoring indicated a delay of the onset of degradation processes by approximately two orders of magnitude in time. Mainly based on the spectroscopic investigations, the corrosion inhibiting effects of the investigated polymer are attributed to the adsorption of a primary polymer layer with a thickness of a few nanometers which occurs within some seconds. Immersion of magnesium for several hours brings up a protective film with around ten nanometers thickness.