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Photochromic radionuclide-based “claw machines” characterizedviaa combination of isothermal titration calorimetry and spectroscopic analysis unlock a pathway for on demand radionuclide capture and release. 

Bridging the current gap between the precision and efficiency demonstrated by natural systems and synthetic materials requires interfacing and independently controlling multiple stimuli-responsive building blocks in a single platform. The mentioned orthogonal control over material properties (i.e., the ability to selectively activate one stimuli-responsive moiety without affecting another) could pave the way for a multitude of applications, including logic-gated optoelectronics, on-demand drug delivery platforms, and molecular shuttles, for example. In this Review, we highlight the recent successful strategies to achieve orthogonal control over material properties using a combination of stimuli-responsive building blocks and multiple independent stimuli. We begin by surveying the fundamental studies of multi-stimuli-responsive systems, which utilize a variety of stimuli to activate a single stimuli-responsive moiety (e.g., spiropyran, diarylethene, or dihydroazulene derivatives), because these studies lay the foundation for the design of systems containing more than one independently controlled fragment. As a next step, we overview the emerging field focusing on systems which are composed of more than one unique stimuli-responsive unit that can respond to independent stimuli, including distinct excitation wavelengths, or a combination of light, heat, pH, potential, or ionic strength. Recent advances clearly demonstrate how strategic coupling of orthogonally controlled stimuli-responsive units can allow for selective modulation of a range of material properties, such as conductivity, catalytic performance, and biological activity. Thus, the highlighted studies foreshadow the emerging role of materials with orthogonally controlled properties to impact the next generation of photopharmacology, nanotechnology, optoelectronics, and biomimetics. 

Abstract In this work, we report the regiospecific and stereoselective synthesis of novel pyrrolo thioxoimidazolidinones with promising biological activities due to the inherent pharmaceutical properties of thioxoimidazolidinone core. The reaction of different thioxoimidazolidinones withtrans‐4‐ethoxy‐1,1,1‐trifluorobut‐3‐en‐2‐one (ETFBO) yields bicyclic 1,3‐diaza heterocycles bearing the trifluoromethyl (CF₃) moiety. Our investigation involved both depth experimental analysis and theoretical calculations to fathom out the mode of reaction of this building block and elucidate the underlying mechanism operating for the observed reactions. Remarkably, this unusual mechanism retained the ethanol moiety from the building block in the final products, deviating from conventional nucleophilic reactions reported in the literature. 

Thermal isomerization reaction pathways through biradical species.