The current study reports the one-step synthesis and gelation properties of cyclohexane-based bis(acyl-semicarbazide) gelators with an additional -NH group incorporated into urea moieties and carrying hydrophobic chains of varying length (C8-C18). The gels exhibited thermoreversibility and could be tuned in the presence of anions at different concentrations in addition their the ultrasound-responsive nature, thus making them multi-stimuli-responsive. The combined experimental and computational study on these gels reveals that the balance between two noncovalent interactions, viz., hydrogen bonding between the amide groups in acyl-semicarbazide moieties and van der Waals forces between long hydrocarbon tails, is found to be the determining factor in the process of organogelation. A systematic increase in alkyl chain length leads to equilibrium between these two types of noncovalent forces that is manifested in the spectral and thermal properties of the gels. The H-bonding interactions dominated up to a certain chain length, and further increases in the alkyl chain length led to increased van der Waals interactions as observed by IR, XRD, and thermal studies. Computational calculations were carried out on dimer structures of C8-C18 to understand the variation in noncovalent forces responsible for aggregate formation in the gel state as a function of the alkyl chain length. The results indicate that both intermolecular and intramolecular hydrogen bonding stabilize the aggregate structures. Supramolecular aggregation in the gel state led to the viscoelastic nature of the gels, and the addition of anions led to the disruption of self-assembly, which was studied by rheology.

Porphyrins dyes are known as promising sensitizers for dye sensitized solar cell (DSC) devices because of their intrinsic features with maximum reported light-to-electricity conversion efficiency of about 12%. Our objective in this study is to rationally design new porphyin sensitizers with enhanced photovoltaic (PV) properties, V oc (open-circuit voltage), or J sc (short-circuit current density) for DSC applications. We have used quantitative structure-property relationship technique following a heuristic approach to build a structure-property (PV) relationship on a dataset of 45 experimentally reported push-pull Zn-porphyrin based sensitizers. The model is further used to predict PV properties; V oc and J sc of 71 new structures. The model includes a unique combination of constitutional, topological, and electrostatic descriptors along with the widely used quantum chemical descriptors to establish a structure-property relationship. The results furnished guide-in principles in identifying 8 structures as potential candidates based on their frontier molecular orbital energies, absorption in visible-near IR region (extending up to 900 nm), reorganization energies, in addition to favorable PV properties. In conclusion, the study has demonstrated how a subtle variation in porphyrin structure particularly of the auxiliary groups can be used to modulate their PV properties. K E Y W O R D S descriptors, dye sensitized solar cell, Porphyrin sensitizers, quantitative structure-property relationship, Voc and Jsc Int J Quantum Chem. 2017;117:e25385.

Molecular property diagnostic suite (MPDS) is a Galaxy-based open source drug discovery and development platform. MPDS web portals are designed for several diseases, such as tuberculosis, diabetes mellitus, and other metabolic disorders, specifically aimed to evaluate and estimate the drug-likeness of a given molecule. MPDS consists of three modules, namely data libraries, data processing, and data analysis tools which are configured and interconnected to assist drug discovery for specific diseases. The data library module encompasses vast information on chemical space, wherein the MPDS compound library comprises 110.31 million unique molecules generated from public domain databases. Every molecule is assigned with a unique ID and card, which provides complete information for the molecule. Some of the modules in the MPDS are specific to the diseases, while others are non-specific. Importantly, a suitably altered protocol can be effectively generated for another disease-specific MPDS web portal by modifying some of the modules. Thus, the MPDS suite of web portals shows great promise to emerge as disease-specific portals of great value, integrating chemoinformatics, bioinformatics, molecular modelling, and structure- and analogue-based drug discovery approaches.

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