A Cryptand-Type Aluminum Tris(salophen) Complex: Synthesis, Characterization, and Cell Imaging Application

Abstract

Abstract:Metal salen/salophen complexes have been used as fluorescent probes for cell imaging with various metal centers. Herein we synthesized cryptand-type aluminum salophen complexes LAl 3 and the corresponding mononuclear compound LAl. X-ray crystal diffraction verifies the cryptand-type structure of LAl 3 with C 3h symmetry. Both LAl 3 and LAl show moderate green fluorescence with quantum yields of 0.17 and 0.05, respectively. The hydrophilic and cationic nature of these aluminum salophen complexes renders them enhanced cellular uptake. Both complexes are internalized into cells by energy-dependent pathways and they distribute in lysosomal organelles.

Tri-Manganese(III) Salen-Based Cryptands: A Metal Cooperative Antioxidant Strategy that Overcomes Ischemic Stroke Damage In Vivo

“…Early on Akine, − Nabeshima, and others pioneered the chemistry of Salen-based cryptands with an eye toward improving guest recognition and selectivity for a range of applications, including materials and catalysis. Within the context of ongoing efforts to explore potential biological applications of metallosalen complexes, − we have recently reported biocompatible luminescent Zn and Al tris­(Salen) cryptands that are effective for live cell imaging. We reasoned that such complexes could also provide a platform for the cooperative binding of guest molecules as the result of the metal centers being in close proximity.…”

“…Three diamines were chosen, namely, o -phenylenediamine, 1,2-diaminocyclohexane, and ethylenediamine. They were incorporated into the three-dimensional hosts , by heating “3, 3’, 3”-methanetriyltris­(2-hydroxybenzaldehyde) at reflux with the chosen diamine (1.5 equiv) and Mn­(OAc) 2 (1.5 equiv) in a mixed CH 3 CN/MeOH solution (1:1). This afforded complexes 1 – 3 in good yields (≥40% in all cases).…”

The Supramolecular Attitude of Metal–Salophen and Metal–Salen Complexes

“…The supramolecular attitude of these scaffolds makes them perfect candidates for a series of important applications especially in the field of materials [53,54] and biological studies [55][56][57]. …”