Hierarchy of π-Stacking Determines the Conformational Preferences of Bis-Squaramates

CrystEngComm ◽  
2021 ◽  
Author(s):  
Abhishek Singh ◽  
Reman Kumar Singh ◽  
G. Naresh Patwari

A rational design of molecular building blocks leading to their aggregation in the solid-state requires control over the intricate array of non-covalent interactions and can serve as anchors in functional...

2021 ◽  
Author(s):  
Serena Gentile ◽  
Erica Del Grosso ◽  
Leonard J. Prins ◽  
Francesco Ricci

Taking advantage of the addressability and programmability of DNA/DNA non-covalent interactions we report here the rational design of orthogonal DNA-based addressable tiles that self-assemble into polymer-like structures that can be reconfigured and reorganized by external inputs. The different tiles share the same 5-nucleotide sticky ends responsible for self-assembly but are rationally designed to contain a specific regulator-binding domain that can be orthogonally targeted by different DNA regulator strands (activators and inhibitors). We show that by sequentially adding specific activators and inhibitors it is possible to re-organize in a dynamic and reversible way the formed polymer-like structures to display well-defined distributions: homopolymers made of a single tile, random polymers in which different tiles are distributed randomly and block structures in which the tiles are organized in segments.


2021 ◽  
Author(s):  
Serena Gentile ◽  
Erica Del Grosso ◽  
Leonard J. Prins ◽  
Francesco Ricci

Taking advantage of the addressability and programmability of DNA/DNA non-covalent interactions we report here the rational design of orthogonal DNA-based addressable tiles that self-assemble into polymer-like structures that can be reconfigured and reorganized by external inputs. The different tiles share the same 5-nucleotide sticky ends responsible for self-assembly but are rationally designed to contain a specific regulator-binding domain that can be orthogonally targeted by different DNA regulator strands (activators and inhibitors). We show that by sequentially adding specific activators and inhibitors it is possible to re-organize in a dynamic and reversible way the formed polymer-like structures to display well-defined distributions: homopolymers made of a single tile, random polymers in which different tiles are distributed randomly and block structures in which the tiles are organized in segments.


Molecules ◽  
2021 ◽  
Vol 26 (21) ◽  
pp. 6731
Author(s):  
Haruki Inoue ◽  
Yuga Yamashita ◽  
Yoshiki Ozawa ◽  
Toshikazu Ono ◽  
Masaaki Abe

Two hexanuclear paddlewheel-like clusters appending six carboxylic-acid pendants have been isolated with the inclusion of polar solvent guests: [Cu6(Hmna)6]·7DMF (1·7DMF) and [Ag6(Hmna)6]·8DMSO (2·8DMSO), where H2mna = 2-mercaptonicotininc acid, DMF = N,N’-dimethylformamide, and DMSO = dimethyl sulfoxide. The solvated clusters, together with their fully desolvated forms 1 and 2, have been characterized by FTIR, UV–Vis diffuse reflectance spectroscopy, TG-DTA analysis, and DFT calculations. Crystal structures of two solvated clusters 1·7DMF and 2·8DMSO have been unambiguously determined by single-crystal X-ray diffraction analysis. Six carboxylic groups appended on the clusters trap solvent guests, DMF or DMSO, through H-bonds. As a result, alternately stacked lamellar architectures comprising of a paddlewheel cluster layer and H-bonded solvent layer are formed. Upon UV illumination (λex = 365 nm), the solvated hexasilver(I) cluster 2·8DMSO gives intense greenish-yellow photoluminescence in the solid state (λPL = 545 nm, ΦPL = 0.17 at 298 K), whereas the solvated hexacopper(I) cluster 1·7DMF displays PL in the near-IR region (λPL = 765 nm, ΦPL = 0.38 at 298 K). Upon complete desolvation, a substantial bleach in the PL intensity (ΦPL < 0.01) is observed. The desorption–sorption response was studied by the solid-state PL spectroscopy. Non-covalent interactions in the crystal including intermolecular H-bonds, CH···π interactions, and π···π stack were found to play decisive roles in the creation of the lamellar architectures, small-molecule trap-and-release behavior, and guest-induced luminescence enhancement.


2011 ◽  
Vol 76 (3) ◽  
pp. 317-328 ◽  
Author(s):  
Zdravko Dzambaski ◽  
Milovan Stojanovic ◽  
Marija Baranac-Stojanovic ◽  
Dragica Minic ◽  
Rade Markovic

Configurational isomerization of stereo-defined 5-substituted and unsubstituted 2-alkylidene-4-oxothiazolidines 1 in the solid state, giving the Z/E mixtures in various ratios, was investigated by 1H-NMR spectroscopy, X-ray powder crystallography and differential scanning calorimetry (DSC). The Z/E composition can be rationalized in terms of non-covalent interactions, involving intermolecular and intramolecular hydrogen bonding and directional non-bonded 1,5-type S...O interactions. X-Ray powder crystallography, using selected crystalline (Z)-4- oxothiazolidine substrates, revealed transformation to the amorphous state during the irreversible Z ? E process. A correlation between previous results on the Z/E isomerization in solution and now in the solid state was established.


Polyhedron ◽  
2020 ◽  
pp. 114895
Author(s):  
Mikhail A. Bondarenko ◽  
Marianna I. Rakhmanova ◽  
Pavel E. Plyusnin ◽  
Pavel A. Abramov ◽  
Alexander S. Novikov ◽  
...  

2019 ◽  
Vol 43 (4) ◽  
pp. 1757-1763 ◽  
Author(s):  
Carolyne B. Braga ◽  
Weslley G. D. P. Silva ◽  
Roberto Rittner

The conformational preferences and role of non-covalent interactions on the geometries of Ac–Pro–NHMe were elucidated in isolated phase and solution.


2018 ◽  
Vol 42 (10) ◽  
pp. 7956-7968 ◽  
Author(s):  
Harrison Omorodion ◽  
Miguel Palenzuela ◽  
Manuel Ruether ◽  
Brendan Twamley ◽  
James A. Platts ◽  
...  

Three hosts for the encapsulation of perfluorooctanoic acid have been synthesized. The host:guest complexes have been characterized by multinuclear NMR spectroscopy in solution and the solid state.


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