A new series of (S)-flurbiprofen derivatives 4a–4p and 5a–5n were synthesized with different aromatic or aliphatic aldehydes and ketones to produce Schiff’s bases and their structures were confirmed through HR-ESI-MS, ¹H, and ¹³C-NMR spectroscopy. The α-glucosidase inhibitory activities of the newly synthesized compounds were scrutinized, in which six compounds 5k, 4h, 5h, 4d, 4b, and 5i showed potent inhibition in the range of 0.93 to 10.26 µM, respectively, whereas fifteen compounds 4c, 4g, 4i, 4j, 4l, 4m, 4o, 4p, 5c, 5d, 5j, 5l, 5m, 5n and 1 exhibited significant inhibitory activity with IC₅₀ in range of = 11.42 to 48.39 µM. In addition, compounds 5g, 5f, 4k, 4n, and 4f displayed moderate-to-low activities. The modes of binding of all the active compounds were determined through the molecular docking approach, which revealed that two residues, specifically Glu277 and His351 are important in the stabilization of the active compounds in the active site of α-glucosidase. Furthermore, these compounds block the active site with high binding energies (−7.51 to −3.36 kcal/mol) thereby inhibiting the function of the enzyme.

Urease belongs to the family of amid hydrolases with two nickel atoms in their core structure. On the basis of literature survey, this research work is mainly focused on the study of bis-Schiff base derivatives of benzyl phenyl ketone nucleus. Synthesis of benzyl phenyl ketone based bis-Schiff bases in search of potent urease inhibitors. In the current work, bis-Schiff bases were synthesized through two steps reaction by reacting benzyl phenyl ketone with excess of hydrazine hydrate in ethanol solvent in the first step to get the desired hydrazone. In last, different substituted aromatic aldehydes were refluxed in catalytic amount of acetic acid with the desired hydrazone to obtain bis-Schiff base derivatives in tremendous yields. Using various spectroscopic techniques including FTIR, HR-ESI-MS, and ¹H NMR spectroscopy were used to clarify the structures of the created bis-Schiff base derivatives. The prepared compounds were finally screened for their in-vitro urease inhibition activity. All the synthesized derivatives (3–9) showed excellent to less inhibitory activity when compared with standard thiourea (IC₅₀ = 21.15 ± 0.32 µM). Compounds 3 (IC₅₀ = 22.21 ± 0.42 µM), 4 (IC₅₀ = 26.11 ± 0.22 µM) and 6 (IC₅₀ = 28.11 ± 0.22 µM) were found the most active urease inhibitors near to standard thiourea among the synthesized series. Similarly, compound 5 having IC₅₀ value of 34.32 ± 0.65 µM showed significant inhibitory activity against urease enzyme. Furthermore, three compounds 7, 8, and 9 exhibited less activity with IC₅₀ values of 45.91 ± 0.14, 47.91 ± 0.14, and 48.33 ± 0.72 µM respectively. DFT used to calculate frontier molecular orbitals including; HOMO and LUMO to indicate the charge transfer from molecule to biological transfer, and MEP map to indicate the chemically reactive zone suitable for drug action. The electron localization function (ELF), non-bonding orbitals, AIM charges are also calculated. The docking study contributed to the analysis of urease protein binding.

Polyhydroquinoline (PHQ) are the unsymmetrical Hantzsch derivatives of 1,4-dihydropyridines with several biological applications. In this work, twenty-five (3–27) new Schiff’s base derivatives of polyhydroquinoline hydrazide were synthesized in excellent to good yields by a multi-component reaction. The structures of the synthesized products (1–27) were deduced with the help of spectroscopic techniques, such as ¹H-, ¹³C -NMR, and HR-ESI-MS. The synthesized products (1–27) were tested for their antibacterial and in vitro calcium -channel-blocking (CCB) potentials using the agar-well diffusion method, and isolated rat aortic ring preparations, respectively. Among the series, sixteen compounds were found to inhibit the growth of Escherichia coli and Enterococcus faecalis. Among them, compound 17 was observed to be the most potent one at a dose 2 µg/mL, with an 18 mm zone of inhibition against both bacteria when it was compared with the standard drug amoxicillin. Eight compounds showed CCB activity of variable potency; in particular, compound 27 was more potent, with an EC₅₀ value of 0.7 (0.3–1.1) µg/mL, indicating their CCB effect.

This research work is based on the synthesis of bis-Schiff base derivatives of the commercially available ibuprofen drug in outstanding yields through multistep reactions. Structures of the synthesized compounds were confirmed by the help of modern spectroscopic techniques including high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), ¹H NMR, and ¹³C NMR. The synthesized compounds were evaluated for their anticancer activity using a normal human embryonic kidney HEK293 cell and U87-malignant glioma (ATCC-HTB-14) as a cancer cell line. All of the synthesized compounds among the series exhibited excellent to less antiproliferative activity having IC₅₀ values ranging from 5.75 ± 0.43 to 150.45 ± 0.20 μM. Among them, compound 5e (IC₅₀ = 5.75 ± 0.43 μM) was found as the most potent antiprolifarative agent, while 5f, 5b, 5a, 5n, 5r, 5s, 5g, 5q, 5i, and 5j exhibited good activity with IC₅₀ values from 24.17 ± 0.46 to 43.71 ± 0.07 μM. These findings suggest that these cells (HEK293) are less cytotoxic to the activities of compounds and increase the cancer cell death in brain, while the lower cytotoxicity of the potent compounds in noncancerous cells suggests that these derivatives will provide promising treatment for patients suffering from brain cancer. The results of the docking study exposed a promising affinity of the active compounds toward casein kinase-2 enzyme, which shows green signal for cancer treatment.