We report lipase-catalyzed inclusion of p-hydroxy benzylalcohol to peptide bolaamphiphiles. The lipase-catalyzed reactions of peptide bolaamphiphiles with p-hydroxy benzylalcohol generate dynamic combinatorial libraries (DCL) in aqueous medium that mimic the natural dissipative system. The peptide bolaamphiphile 1 (HO-WY-Suc-YW-OH) reacts with p-hydroxy benzylalcohol in the presence of lipase forming an activated diester building block. The activated diester building block self-assembles to produce nanofibrillar thixotropic hydrogel. The subsequent hydrolysis results in the dissipation of energy to form nonassembling bolaamphiphile 1 with collapsed nanofibers. The thixotropic DCL hydrogel matrix is used for 3D cell culture experiments for different periods of time, significantly supporting the cell survival and proliferation of human umbilical cord mesenchymal stem cells.

The mechanistic aspects of supramolecular ordering of synthetic β‐amino acid based peptides in different organic solvents and fuel oils are reported. The peptide Boc‐cis‐ACHC‐Aib‐Phe‐OMe (Boc=tert‐butyloxycarbonyl, cis‐ACHC=cis‐2‐aminocyclohexanecarboxylic acid, Aib=α‐amino isobutyric acid, Phe=phenylalanine; 1) is able to entrap various organic solvents and oils, leading to the formation of self‐supporting gels. Spectroscopic studies confirm the turn‐type β‐sheet arrangement of peptide 1 in the gel phase. A morphology study shows that a bundle of nanofibers form from self‐assembled peptide 1. Peptide 1 is capable of entrapping organic or oil layers selectively over the aqueous layer. Furthermore, the phase‐selective gelation behavior of peptide 1 is effectively used as a model study for oil spill recovery from a biphasic mixture of oil and water.

Here, we report the effects of electron donor and acceptor units attached with benzoselenadiazole for the change in optoelectronic and packing patterns in solid states. We have synthesized 4-methoxybenzene, naphthalene, and 4-nitrobenzene capped benzoselenadiazoles (compounds 1–3 respectively) and studied their photophysical as well as electrochemical properties. All three molecules show two absorption bands (π–π transition band and CT-band). Three molecules (1–3) show orange, yellow-green, and green colors in dichloromethane solutions upon irradiation of UV light at 365 nm. Benzoselenadiazole-based compounds 1–2 form head to head dimers via Se···N interactions in the solid states. Compounds 1 and 2 show interlock type packing via Se···N interaction in their solid state structures. Se···π interaction takes a major role to form interlocked sheet type structures in crystal packing of compound 1, whereas Se···N, N···N, and CH···π interactions help to form a supramolecular sheet type of structure in the crystal packing of compound 2. Band gaps of these compounds were tuned by changing the electron donating to electron withdrawing units attached with a benzoselenadiazole core.

We use the oxo-ester mediated native chemical ligation (NCL) reaction to generate a peptide self-assembly process to make supramolecular nanofibers and self-supporting gels.

Regulating the nanostructural morphology of synthetic hybrid peptides through external stimuli is still a great challenge. Here, we report the synthesis of constrained amino acid building block gabapentin (Gpn) based hybrid peptides and their structural and morphological diversity in different conditions. The synthesized three hybrid peptides Boc-Gpn-Aib-Phe-Aib-OMe (P), Boc-Gpn-Aib-Leu-Aib-OMe (P) and Boc-Gpn-Aib-Tyr-Aib-OMe (P) are folded into C12/C10 hydrogen-bonded double turn conformations. The double turn feature is probed and confirmed by conformational analysis of hybrid peptides using 2D-NMR studies and X-ray crystallography. DMSO-d6 solvent titration investigations also support the double turn conformation adopted by our reported peptides in CDCl3 solution. Solvent assisted self-assembled morphological features of peptides P-P and the salt-prompted mineralization studies of peptide P under ambient conditions are studied. All three reported peptides P-P form diverse supramolecular scaffolds in solid states through non-covalent interactions to attain higher order architectures.