Development and synthesis of a novel salen-type ligand based on phenylalanine for Mizoroki-Heck, and S-arylation cross-coupling reactions.

In this article, we introduced a novel salen-type ligand precursor and applied it in the Pd-catalyzed Mizoroki-Heck and Cu-catalyzed S-arylation cross-coupling reactions. For the preparation of this structure, (DL)-phenyl alanine was employed as a starting material. These ligand precursor and related catalytic system can be readily synthesised. Various aryl halides (-I, -Br) and alkenes were applied successfully in this protocol to give the corresponding Mizoroki-Heck cross-coupling and S-arylated products in high to excellent yields.

Incensole derivatives from frankincense: Isolation, enhancement, synthetic modification, and a plausible mechanism of their anti-depression activity.

Encouraged by the potent anti-depression activities of incensole (1) and incensole acetate (2) isolated from the resin of Boswellia papyrifera in our previous work, different derivatives of 1 and 2 were synthesized in the present study. The reaction of 1 with m-CPBA afforded the mono-epoxide derivative 3a, while the same reaction with 2 led to three different epoxide derivatives 3a, 3b, and 3c. Oxidation of 1 with PCC to get compound 3b, however along with the target 3b, the reaction gave three interesting side products (3c-3e). Oxime (3b-1) resulted from the reaction of 3b with hydroxylamine hydrochloride in pyridine, while epoxidation of 2 generate three epoxide products (4a-4c). The structures of all products were unambiguously confirmed using NMR and Mass spectrometry. Compounds 3a-e and 4a-c (0.1-3 mg/kg, i.p.) demonstrated promising anti-depression activities in classical mouse models of depression of FST and TST. The results showed that compounds 3a-e and 4a-c (0.1-3 mg/kg, i.p.) caused dose dependent reduction in immobility time compared to the vehicle control, with 3c-3e and 4b-4c demonstrating higher potency and efficacy. The findings of the open field test excluded the motor effects of these compounds, thus further confirming their anti-depression activity. Preliminary investigation into their mechanism of action using GABA antagonist, PTZ and molecular docking has predicted that compounds 3e and 4c bind at the GABA binding site of GABAA receptor to produce GABAergic effects. Furthermore, the promising anti-depression potency of compounds 1 and 2 and their derivatives make them lead compounds for drug discovery.

Wet chemical development of CuO/GO nanocomposites: its augmented antimicrobial, antioxidant, and anticancerous activity.

This study employed a bottom-up technique to synthesize copper oxide (CuO) nanoparticles over hydrophilic graphene oxide (GO) nanosheets. The CuO/GO nanocomposite has been prepared using two selected precursors of copper nitrate and citric acid with an intermittent mixing of GO solutions. The synthesized Nanocomposites were characterized using different biophysical techniques like FT-IR, NMR, FE-SEM, and HR-TEM analyses. FT-IR analyses confirm the nanocomposites' successful formation, which is evident from the functional groups of C=C, C-O, and Cu-C stretching vibrations. Morphological analyses reveal the depositions of CuO nanoparticles over the planar rough GO sheets, which has been elucidated from the FE-SEM and HR-TEM analyses supported by respective EDAX analyses. The antimicrobial activities have been evident from the surface roughness and damages seen from the FE-SEM analyses. The CuO/GO sheets were tested against Gram-positive (e.g., Staphylococcus aureus) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa). It is evident that the intrinsic antibacterial activity of CuO/GO sheets, when combined in equal proportions, elicited a robust antibacterial activity when tested over Gram -ve representative bacteria Escherichia coli. The antioxidant behaviour of synthesized CuO/GO nanocomposite was evaluated by scavenging the free radicals of DPPH and ABTS. Moreover, the cytotoxic activity was also studied against epidermoid carcinoma cell line A-431. A brief mathematical formulation has been proposed in this study to uncover the possibilities of using the nanocomposites as potential drug candidates in theranostic applications in disease treatment and diagnosis. This study would help uncover the electronic properties that play in the nano-scaled system at the material-bio interface, which would aid in designing a sensitive nano-electromechanical device bearing both the therapeutic and diagnostic attributes heralding a new horizon in the health care systems.

New bioactive macrocyclic diterpenoids from Jatropha multifida.

Two new macrocyclic diterpenoids, multifidanol (1) and multifidenol (2) along with several known compounds have been isolated from the stem of Jatropha multifida. The structures of the new compounds were established from the extensive studies of their 1D and 2D NMR spectra. The cytotoxic and antimicrobial activities of these two constituents were examined.