Broadband-Light-Induced [2+2] Cycloaddition and Thermoinduced Cycloreversion-Powered Dynamic Molecular Crystals.

Photomechanically responsive dynamic molecular crystals are central to developing efficient, rapid, and robust materials capable of conversion of light energy to mechanical work. However, unlike some other, mainly photochromic molecular solar thermal energy storage (MOST) systems, solids that undergo photoinduced [2+2] cycloaddition have not been thoroughly explored for powering reversible actuation, despite that this reaction system carries potential in the heavily strained bonds of the cyclobutane ring. In this study, we propose that broadband-light-induced [2+2] cycloaddition can be used to store energy and actuate dynamic organic crystals by irradiation with visible light.

Strategies to Diversification of the Mechanical Properties of Organic Crystals.

Structurally ordered soft materials that respond to complementary stimuli are susceptible to control over their spatial and temporal morphostructural configurations by intersectional or combined effects such as gating, feedback, shape-memory, or programming. In the absence of general and robust design and prediction strategies for their mechanical properties, at present, combined chemical and crystal engineering approaches could provide useful guidelines to identify effectors that determine both the magnitude and time of their response. Here, we capitalize on the purported ability of soft intermolecular interactions to instigate mechanical compliance by using halogenation to elicit both mechanical and photochemical activity of organic crystals.

Flavonoids from Rhododendron nivale Hook. f delay aging via modulation of gut microbiota and glutathione metabolism.

Background: Rhododendron nivale Hook. f (R.n), one of the four Manna Stash used in Tibetan medicine to delay aging, possesses anti-aging pharmacological activity.