A novel scaffold for effective wound healing treatment was developed utilizing natural product bearing collagen-based biocompatible electrospun nanofibers. Initially, ostholamide (OSA) was synthesized from osthole (a natural coumarin), characterized by H,C, DEPT-135 NMR, ESI-MS, and FT-IR spectroscopy analysis. OSA was incorporated into polyhydroxybutyrate (PHB) and gelatin (GEL), which serve as templates for electrospun nanofibers. The coating of OSA-PHB-GEL nanofibers with collagen resulted in PHB-GEL-OSA-COL nanofibrous scaffold which mimics extracellular matrix and serves as an effective biomaterial for tissue engineering applications, especially for wound healing. PHB-GEL-OSA-COL, along with PHB-GEL-OSA and collagen film (COLF), was characterized in vitro and in vivo to determine its efficacy. The developed PHB-GEL-OSA-COL nanofibers posed an impressive mechanical stability, an essential requirement for wound healing. The presence of OSA had contributed to antimicrobial efficacy. These scaffolds exhibited efficient antibacterial activity against common wound pathogens, Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus). The zones of inhibition were observed to be 14 ± 22 and 10 ± 2 mm, respectively. It was observed that nanofibrous scaffold had the ability to release OSA in a controlled manner, and hence, OSA would be present at the site of application and exhibit bioactivity in a sustained manner. PHB-GEL-OSA-COL nanofiber was determined to be stable against enzymatic degradation, which is the most important parameter for promoting proliferation of cells contributing to repair and remodeling of tissues during wound healing applications. As hypothesized, PHB-GEL-OSA-COL was observed to imbibe excellent cytocompatibility, which was determined using NIH 3T3 fibroblast cell proliferation studies. PHB-GEL-OSA-COL exhibited excellent wound healing efficacy which was confirmed using full thickness excision wound model in Wistar rats. The rats treated with PHB-GEL-OSA-COL nanofibrous scaffold displayed enhanced healing when compared to untreated control. Both in vitro and in vivo analysis of PHB-GEL-OSA-COL presents a strong case of therapeutic biomaterial suiting wound repair and regeneration.

Rhodium-catalysed decarbonylative annulation of isatoic anhydrides with alkynes through C-H activation for the synthesis of aminoisocoumarins was developed. This enables the gram-scale transformation to iodoisocoumarin which is a vital building block in transition-metal-catalysed cross couplings. These compounds exhibit blue-emitting luminescence properties.

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We report the synthesis of spirooxindole–pyrrolidines tethered with indole and pyridine heterocycles using 1,3-dipolar cycloaddition, and their anticancer activities and molecular docking studies.

A facile ruthenium(II)-catalyzed regiospecific C–H/O–H oxidative annulation methodology was developed to construct isochromeno[8,1-ab]phenazines. This methodology delivers various advantages, such as scope for diverse substrates, tolerance to a range of functional groups, stability under air, and yields regioselective products. This methodology was successfully applied to synthesize far red (FR) fluorescent probes for live cancer cell imaging. The synthesized compounds displayed notable fluorescence properties in solution and thin-film. Their application in live cancer cell imaging was investigated using various cancer cell lines. The synthesized compound showed prominent FR fluorescence, with high quantum yield, and exhibited better cell-imaging properties, with excellent biocompatibility.