The trifluoromethyl (CF 3) group is an advantageous structural motif in various biologically active molecules as well as materials, which is depicted by steadily increasing demand from the industries involved in drug discovery, agrochemicals and material development. β-trifluoromethyl α,βunsaturated carbonyl compounds constitute a very efficient building blocks as starting material in the synthesis of fluorinated molecules. Their usage for the synthesis of various heterocycles and organic molecules bearing stereogenic carbon containing CF 3 motif has received significant attention during the recent times. This review provides the existing methods for the synthesis of β-substituted trifluoromethyl-α,β-unsaturated ketones and the efforts made by researchers for the synthetic development through various reactions by employing them as synthetic building blocks for trifluoromethylated organic scaffolds.

Peptides are signaling epitopes that control many vital biological events. Increased specificity, synthetic feasibility with concomitant lack of toxicity, and immunogenicity make this emerging class of biomolecules suitable for different applications including therapeutics, diagnostics, and biomedical engineering. Further, chitosan, a naturally occurring linear polymer composed of D-glucosamine and N-acetyl-D-glucosamine units, possesses anti-microbial, muco-adhesive, and hemostatic properties along with excellent biocompatibility. As a result, chitosan finds application in drug/gene delivery, tissue engineering, and bioimaging. Despite these applications, chitosan demonstrates limited cell adhesion and lacks biosignaling. Therefore, peptide−chitosan hybrids have emerged as a new class of biomaterial with improved biosignaling properties and cell adhesion properties. As a result, recent studies encompass increased application of peptide−chitosan hybrids as composites or conjugates in drug delivery, cell therapy, and tissue engineering and as anti-microbial material. This review discusses the recent investigations involving chitosan−peptide materials and uncovers various aspects of these interesting hybrid materials for biomedical applications.

Owing to their properties such as biocompatibility, tunable mechanical properties, permeability toward oxygen, nutrients, and the ability to hold a significant amount of water, hydrogels have wide applications in biomedical research. They have been engaged in drug delivery systems, 3D cell culture, imaging, and extracellular matrix (ECM) mimetics. Injectable hydrogels represent a major subset of hydrogels possessing advantages of site-specific conformation with minimal invasive techniques. It preserves the inherent properties of drug/biomolecules and is devoid of any side effects associated with surgery. Various polymeric materials utilized in developing injectable hydrogels are associated with the limitations of toxicity, immunogenicity, tedious manufacturing processes, and lack of easy synthetic tunability. Peptides are an important class of biomaterials that have interesting properties such as biocompatibility, stimuli responsiveness, shear thinning, self-healing, and biosignaling. They lack immunogenicity and toxicity. Therefore, numerous peptide-based injectable hydrogels have been explored in the past, and a few of them have reached the market. In recent years, minimalistic dipeptides have shown their ability to form stable hydrogels through cooperative noncovalent interactions. In addition to inherent properties of lengthy peptide-based injectable hydrogels, dipeptides have the unique advantages of low production cost, high synthetic accessibility, and higher stability. Given the instances of expanding significance of injectable peptide hydrogels in biomedical research and an emerging recent trend of dipeptide-based injectable hydrogels, a timely review on dipeptide-based injectable hydrogels shall highlight various aspects of this interesting class of biomaterials. This concise review that focuses on the dipeptide injectable hydrogel may stimulate the current trends of research on this class of biomaterial to translate its significance as interesting products for biomedical applications.

An efficient synthesis of 3-trifluoromethylindanones via C–H annulation of N-methoxybenzamides with β-trifluoromethyl-α,β-unsaturated ketones under Rh(iii)-catalysis is described.

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