Bagadhar Brahma Kishan College

A mild and concise method for the synthesis of chromenopyrrole from 2'-hydroxychalcone is devised. The reaction proceeds via an initial [3 + 2] cycloaddition on the C═C bond of 2'-hydroxychalcone and 1,3-dipolarophile, generated in situ by the reaction of ethyl isocyanoacetate and AgOAc. This is then followed by an intramolecular C-O bond formation with the -OH group and C5-H of the in situ generated pyrrole, leading to chromenopyrroles.

Owing to their unique structural features, isothiocyanates (ITCs) are a class of highly useful and inimitable reagents as the -NCS group serves both as electrophile and nucleophile in organic synthesis. ITCs share a rich legacy in organic, medicinal, and combinatorial chemistry. Compared to their oxygen equivalents, isocyanates, ITCs are easily available, less unpleasant, and somewhat less harmful to work with (mild conditions) which makes them happy-go-lucky reagents. Functionalized ITCs can finely tune the reactivity of the -NCS group and thus can be exploited in the late-stage functionalization processes. This review's primary aim is to outline ITC chemistry in the construction and derivatization of heterocycles through the lens of sustainability. For ease and brevity, the sections are divided based on reactive centers present in functionalized ITCs and modes of cyclisation. Scrutinizing their probable unexplored directions for future research studies is also addressed.

The development of highly sensitive, long-lasting and cost-effective dual hydrogen peroxide (H 2 O[Formula: see text]/glucose sensors is crucial for various industries, particularly in medical, clinical diagnostics, pharmaceuticals, environmental monitoring and food business. In our study titanium dioxide/copper oxide (TiO 2 /CuO) hierarchical nanostructure electrodes have been grown using hydrothermal process and their nonenzymatic H 2 O 2 sensing and glucose sensing properties have been demonstrated using cyclic voltammetry and amperometry measurements. The surface morphology of TiO 2 nanorods (TiO 2 NRs) and TiO 2 /CuO hierarchical nanostructure was investigated using a scanning electron microscope (SEM). The TiO 2 /CuO hierarchical nanostructure electrodes demonstrated sensitivity of 20.09 [Formula: see text]A mM[Formula: see text] cm[Formula: see text] toward H 2 O 2 , in the concentration range 0.25–18.25 mM. The TiO 2 /CuO hierarchical nanostructure electrodes demonstrated a sensitivity of 1.5 mA mM[Formula: see text] cm[Formula: see text] towards glucose, in the concentration range 0.05–5 mM. Furthermore, artificial neural networks (ANN) were used to model the observed experimental results.

This study investigated the physicochemical properties and antioxidant activity of Bambusa tulda tea. The tea exhibited low moisture and ash content, indicative of good drying quality. Its acidic pH was attributed to the presence of organic acids. Phytochemical analysis confirmed the presence of carbohydrates, reducing sugars, triterpenoids and cardiac glycosides. The dry extract contained higher levels of phenolics and flavonoids compared to the infusion, resulting in stronger antioxidant activity, as demonstrated by a lower IC 50 value of 3.794 in the DPPH radical scavenging assay. Furthermore, silica (SiO₂) was extracted from the tea leaves and characterized using X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). These analyses revealed an amorphous structure and spherical morphology. Field Emission Scanning Electron Microscopy (FE-SEM) and Energy Dispersive Spectroscopy (EDS) analyses corroborated the spherical morphology and elemental composition of the SiO₂. The extracted SiO₂ effectively degraded methylene blue and Congo red dyes under sunlight, highlighting the potential of B. tulda tea as a sustainable source of SiO₂ for environmental remediation. • Bambusa tulda tea possesses a rich phytochemical profile having high antioxidant activity. • SiO 2 was successfully extracted from Bambusa tulda tea leaves. • XRD analysis confirmed the amorphous nature of the extracted silica; FTIR spectroscopy revealed characteristic Si-O-Si bond vibrations. • FE-SEM and EDS analysis confirmed the spherical morphology and elemental composition of the SiO 2 . • The extracted SiO 2 demonstrate effective photocatalytic activity for methylene blue and Congo red dyes degradation, suggesting potential for sustainable environmental remediation.

This review article discusses about transformable directing groups in transition metal-catalyzed regioselective C(sp 2 )–H functionalizations.

Hybrid Ultraviolet photodetector (UVPD) was fabricated by depositing reduced graphene oxide on zinc oxide nanorods (ZnO NRs) array-coated FTO glass. Structural and optical properties of ZnO NRs were studied using TEM, SEM, XRD and UV–Vis spectroscopy. Graphene oxide (GO) sheets were synthesized from graphite powder using the modified Hummer’s method. rGO films were obtained after illuminating the GO in UV radiation. The formation of rGO and GO films was studied using AFM surface topography and UV–Vis spectroscopy. External quantum efficiency (EQE), responsivity and transient response of rGO/ZnO NR-based UV photodetector were studied in detail. The photodetector device shows very high EQE ([Formula: see text]45 257%) and responsivity ([Formula: see text][Formula: see text]130 A/W).