Lanthanide-based Metal-organic Frameworks Offering Hydrogen Bonding Cavities: Luminescent Characteristics and Sensing Applications.

This work presents the synthesis and characterization of three isomorphous lanthanide-based metal-organic frameworks (Ln-MOFs) (Ln3+ = Eu (1), Tb (2), and Sm (3)) supported by a pyridine-2,6-dicarboxamide-based linker offering appended arylcarboxylate groups. Single crystal X-ray diffraction studies highlight that these Ln-MOFs present three-dimensional porous architectures offering large cavities decorated with hydrogen bonding (H-bonding) groups. These Ln-MOFs display noteworthy luminescent characteristics.

Selective sensing of picric acid using a Zn(II)-metallacycle: experimental and theoretical validation of the sensing mechanism and quantitative analysis of sensitivity in contact mode detection.

A combination of ,',''-tris(3-pyridyl)-1,3,5-benzenetricarboxamide (L1) and -chlorobenzoic acid (HL2) with Zn(NO)·6HO resulted in the formation of a dinuclear metallacycle [ZnL1(L2)(DMF)] (1(DMF)4). In 1(DMF)4, the Zn(II) centre adopts a square pyramidal geometry, while one of the pyridyl N out of the three pyridyl groups in L1 remained uncoordinated. Solvated DMF molecules are present in 1(DMF)4.

Tailored Inorganic-Organic Architectures via Metalloligands.

This article discusses the design principles and strategies and the structural outcome of various supramolecular architectures constructed by utilizing well-defined coordination complexes as the metalloligands. We have included selected examples of metalloligands, offering either pyridyl or arylcarboxylic acid groups as the appended functional groups, for illustrating the construction of their supramolecular architectures. Both geometrical position and the number of the appended functional groups emerging from a metalloligand were found to critically regulate the structural aspects and dimensionality of the resultant material.

Molecular Assemblies Offering Hydrogen-Bonding Cavities: Influence of Macrocyclic Cavity and Hydrogen Bonding on Dye Adsorption.

This work presents a set of Hg macrocycles of amide-phosphine-based ligands offering H-bonding cavities of different dimensions. Such macrocycles are shown to selectively adsorb anionic dyes followed by neutral dyes as well as Prontosil, a biologically relevant antibiotic, within their cavities with the aid of H-bonding-assisted encapsulation. Kinetic experiments supported by spectroscopic and docking studies illustrate the importance of the cavity structure as well as H-bonds for the selective adsorption of dyes.

Synthesis, In Silico Study, and Anti-Cancer Activity of Thiosemicarbazone Derivatives.

Thiosemicarbazones are known for their biological and pharmacological activities. In this study, we have synthesized and characterized 3-Methoxybenzaldehyde thiosemicarbazone (3-MBTSc) and 4-Nitrobenzaldehyde thiosemicarbazone (4-NBTSc) using IR, HNMR and C NMR. The compound's in vitro anticancer activities against different cell lines were evaluated.

Supramolecular catalysis: the role of H-bonding interactions in substrate orientation and activation.

Hydrogen bonding plays significant roles in various biological processes during substrate orientation and binding and therefore assists in assorted organic transformations. However, replicating the intricate selection of hydrogen bonds, as observed in nature, in synthetic complexes has met with only limited success. Despite this fact, recent times have seen the emergence of several notable examples where hydrogen bonds have been introduced in synthetic complexes.

Half-Sandwich Ruthenium Complexes of Amide-Phosphine Based Ligands: H-Bonding Cavity Assisted Binding and Reduction of Nitro-substrates.

We present synthesis and characterization of two half-sandwich Ru(II) complexes supported with amide-phosphine based ligands. These complexes presented a pyridine-2,6-dicarboxamide based pincer cavity, decorated with hydrogen bonds, that participated in the binding of nitro-substrates closer to the Ru(II) centers, which is further supported with binding and docking studies. These ruthenium complexes functioned as the noteworthy catalysts for the borohydride mediated reduction of assorted nitro-substrates.

Architectural and catalytic aspects of designer materials built using metalloligands of pyridine-2,6-dicarboxamide based ligands.

This perspective presents the design, synthesis and crystal structures of a large number of architectures constructed using assorted metalloligands of pyridine-2,6-dicarboxamide based ligands. The metalloligands offered various appended functional groups, whereas design strategies included varying both their position and number. A combination of these parameters resulted in the development of assorted architectures including discrete trinuclear and tetranuclear complexes as well as 1D/2D/3D coordination polymers.

Zn- and Cd-based Coordination Polymers Offering H-Bonding Cavities: Highly Selective Sensing of S O and Fe Ions.

We present two Zn - and Cd -based coordination polymers (CPs), L-Zn and L-Cd, offering H-bonding-based cavities of varying dimensions. Both CPs were used for the highly selective detection of S O and Fe ions where H-bonding based cavities played an important role. Fluorescence quenching, competitive binding studies and binding parameters substantiated significant recognition of S O and Fe ions by both CPs.

Size-Selective Detection of Picric Acid by Fluorescent Palladium Macrocycles.

This work presents the synthesis and characterization of two palladium-based fluorescent macrocycles offering hydrogen-bonding cavities of contrasting dimensions. Both palladium macrocycles function as chemosensors for the detection of nitroaromatics, whereas the larger macrocycle not only illustrates nanomolar detection of picric acid but also transports its significant amount from an aqueous to an organic phase.