Deoxycholamide Crystalline Frameworks as a Platform of Highly-Efficient Fluorescence Materials

Abstract

To achieve spatially oriented molecular arrays with a wide range of dye molecules, an organic lattice framework is a promising platform, because its flexible superstructure connected by labile hydrogen bonds can tune the host framework to provide the dyes geometrically oriented in the appropriate inclusion spaces. In this Article, we demonstrate that inclusion crystalline lattice composed of deoxycholamide (DCM) can be applied as a platform to arrange various "skinny" dye molecules such as anthracene and 1,6-diphenylhexatriene into a tandemly aligned array without π/π stacking interactions in the inclusion channel. As compared to its parent compound deoxycholic acid (DCA), DCM forms additional NÀH 3 3 3 O interactions between DCM molecules, stabilizing the host framework. The density of the guest dyes included in the DCM channels can be controlled upon changing crystallization solvent: nonpolar solvents give inclusion crystals (ICs) containing a small amount of dye molecules (I-state), while polar ones give ICs whose channels are filled by tandemly arrayed dyes (F-state). ICs of dyes, even in the densely packed F-sate, exhibit fluorescence quantum yields higher than the naked dye crystals and comparable to the diluted solutions.

Nanochannels: Hosts for the Supramolecular Organization of Molecules and Complexes

“…The extent of importance of the polydispersity of the objects depends on the properties that we are studying. We shall not often explicitly refer to this aspect, but it is advisible to keep it in mind. − …”

Molecular Recognition of Steroid Hormones in the Solid State: Stark Differences in Cocrystallization of β-Estradiol and Estrone

“…Whereas single crystal X-ray diffraction has been utilized extensively for studying steroids, − such work has focused mostly on single-component solids or fortuitously obtained solvates and hydrates. Thus, with very few exceptions, − cocrystallization and solid-state complexation of steroid hormones have remained largely unexplored.…”

“…Instead, steroid cocrystallization has been largely used as a noncovalent means to introduce heavy atoms into crystal structures in order to facilitate X-ray structural characterization: this strategy was pioneered in the 1960s by Eger and Norton who used p -bromophenol to facilitate structural characterization of steroids, while the Desiraju group employed a similar strategy to facilitate determination of steroid absolute configuration . Recently, steroid cocrystallization was brought back into the focus of solid-state chemists as a means to develop new pharmaceutical solids with improved properties (e.g., dissolution and tableting). − While the herein described study is primarily of academic nature, directed toward building a fundamental understanding of steroid recognition in the solid state, it is also of potential pharmaceutical and medicinal relevance as it provides the first insights on how to design new solid forms of two steroids of medicinal and pharmaceutical use in hormonal contraception, hormone replacement therapy, and treatment of menopausal and postmenopausal symptoms…”

Simultaneous Arrangement of up to Three Different Molecules on the Pore Surface of a Metal–Macrocycle Framework: Cooperation and Competition

“…[12a,b] In this study, we aimed to simultaneously capture up to three different guest molecules in a site-selective manner on the pore surface, using ferrocene (3), fluorene (4), their hydroxymethylated derivatives (5) and (6), and tetrathiafulvalene (TTF; 2). [13][14][15] As a result, the simultaneous arrangement of three different molecules was successfully achieved in two characteristic adsorption manners, guest-assisted cooperative co-adsorption and competitive adsorption. The structure of the ternary inclusion complex was determined by singlecrystal X-ray diffraction (XRD) analysis.…”