Strain-Induced Photochemical Opening of Ferrocene[6]cycloparaphenylene: Uncaging of Fe with Green Light.

We present the synthesis, structural analysis, and remarkable reactivity of the first carbon nanohoop that fully incorporates ferrocene in the macrocyclic backbone. The high strain imposed on the ferrocene by the curved nanohoop structure enables unprecedented photochemical reactivity of this otherwise photochemically inert metallocene complex. Visible light activation triggers a ring-opening of the nanohoop structure, fully dissociating the Fe-cyclopentadienyl bonds in the presence of 1,10-phenanthroline.

Surfing the limits of cyanine photocages one step at a time.

Near-infrared light-activated photocages enable controlling molecules with tissue penetrating light. Understanding the structural aspects that govern the photouncaging process is essential to enhancing their efficacy, crucial for practical applications. Here we explore the impact of thermodynamic stabilization on contact ion pairs in cyanine photocages by quaternarization of the carbon reaction centers.

Azobenzene-Based Photoswitchable Substrates for Advanced Mechanistic Studies of Model Haloalkane Dehalogenase Enzyme Family.

The engineering of efficient enzymes for large-scale production of industrially relevant compounds is a challenging task. Utilizing rational protein design, which relies on a comprehensive understanding of mechanistic information, holds significant promise for achieving success in this endeavor. Pre-steady-state kinetic measurements, obtained either through fast-mixing techniques or photoswitchable substrates, provide crucial mechanistic insights.

Concurrent Subcellular Delivery of Hydrogen Sulfide and a Payload with Near-Infrared Light.

Hydrogen sulfide (HS) is a gaseous signaling molecule, exerting crucial regulatory functions in organelles and cellular environments. HS exhibits high therapeutic potential and synergistic effects with other drugs, and its potency is notably enhanced through organelle-specific targeting. Yet, the navigation of light-activated HS donors to specific organelles remains absent.

Light in a Heartbeat: Bond Scission by a Single Photon above 800 nm.

Photocages enable scientists to take full control over the activity of molecules using light as a biocompatible stimulus. Their emerging applications in photoactivated therapies call for efficient uncaging in the near-infrared (NIR) window, which represents a fundamental challenge. Here, we report synthetically accessible cyanine photocages that liberate alcohol, phenol, amine, and thiol payloads upon irradiation with NIR light up to 820 nm in aqueous media.