Silver(I)-Tazobactam Frameworks with Improved Antimicrobial Activity

Tazobactam (TazoH) is a penicillinate sulfone β-lactamase inhibitor with negligible antimicrobial activity, commonly used with other antibiotics to provide an effective combination against many susceptible organisms expressing β-lactamases. Two novel Ag(I)-tazobactam frameworks ([Ag(I)-Tazo] and [Ag(I)-Tazo2]) prepared by mechanochemistry are presented herein as alternative forms to improve the antimicrobial activity of tazobactam by exploring synergistic effects with silver, being the first crystal structures reported of tazobactam coordinating to a metal site. The topological analysis of the 3D ([Ag(I)-Tazo]) and 2D+1D ([Ag(I)-Tazo2]) frameworks revealed underlying nets with the cbs (CrB self-dual) and decorated sql topologies, respectively. These novel frameworks are stable and show an enhanced antimicrobial activity when compared to tazobactam alone. Amongst the tested microorganisms, Pseudomonas aeruginosa is the most sensitive to tazobactam and the new compounds. This study thus unveils novel facets of tazobactam chemistry and opens up its application as a multifunctional linker for the design of antibiotic coordination frameworks and related materials.

Mechanochemistry in Portugal-A Step towards Sustainable Chemical Synthesis

In Portugal, publications with mechanochemical methods date back to 2009, with the report on mechanochemical strategies for the synthesis of metallopharmaceuticals. Since then, mechanochemical applications have grown in Portugal, spanning several fields, mainly crystal engineering and supramolecular chemistry, catalysis, and organic and inorganic chemistry. The area with the most increased development is the synthesis of multicomponent crystal forms, with several groups synthesizing solvates, salts, and cocrystals in which the main objective was to improve physical properties of the active pharmaceutical ingredients. Recently, non-crystalline materials, such as ionic liquids and amorphous solid dispersions, have also been studied using mechanochemical methods. An area that is in expansion is the use of mechanochemical synthesis of bioinspired metal-organic frameworks with an emphasis in antibiotic coordination frameworks. The use of mechanochemistry for catalysis and organic and inorganic synthesis has also grown due to the synthetic advantages, ease of synthesis, scalability, sustainability, and, in the majority of cases, the superior properties of the synthesized materials. It can be easily concluded that mechanochemistry is expanding in Portugal in diverse research areas.