Synthesis of novel β-lactams: Antioxidant activity, acetylcholinesterase inhibition and computational studies

Designing a green poly(β-amino ester) for the delivery of nicotinamide drugs with biological activities and conducting a DFT investigation

The environmentally friendly polymerization process was carried out using microwave irradiation without additional solvents or catalysts to produce poly(β-amino ester) (PβAE) which served as a drug delivery system. PβAE was synthesized through Michael addition polymerization of 1,4-butane diol diacrylate and piperazine. Swelling and biodegradation studies were conducted in various solvents and phosphate-buffered saline (PBS, pH 7.4) at 37 °C to evaluate the properties of the polymeric gel. The PβAE matrix demonstrated solubility enhancement for hydrophobic antimicrobial and antitumor-active nicotinamide derivatives (TEINH, APTAT, and MOAPM), controlling their release over 10 days in (PBS). The successful formation of free and loaded PβAE with nicotinamide active materials was confirmed by spectroscopic analysis including Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Optimization and physical descriptor determination via the DFT/B3LYP-631(G) basis set were performed to aid in the biological evaluation of these compounds with elucidation of their physical and chemical interaction between poly(β-amino ester) and nicotinamide drugs.

Penisimplicins A and B: Novel Polyketide-Peptide Hybrid Alkaloids from the Fungus Penicillium simplicissimum JXCC5

In this study, two previously undescribed nitrogen-containing compounds, penisimplicins A (1) and B (2), were isolated from Penicillium simplicissimum JXCC5. The structures of 1 and 2 were elucidated on the basis of comprehensive spectroscopic data analysis, including 1D and 2D NMR and HRESIMS data. The absolute configuration of 2 was determined by Marfey's method, ECD calculation, and DP4+ analysis. Both structures of 1 and 2 feature an unprecedented manner of amino acid-derivatives attaching to a polyketide moiety by C-C bond. The postulated biosynthetic pathways for 1 and 2 were discussed. Additionally, compound 1 exhibited significant acetylcholinesterase inhibitory activity, with IC50 values of 6.35 μM.

Anti-proliferative activity, molecular genetics, docking analysis, and computational calculations of uracil cellulosic aldehyde derivatives

In this study, the oxidation of microcrystalline cellulose using NaIO4 to yield the corresponding cellulose aldehyde utilized microwave irradiation as a green tool, the obtained cellulosic aldehyde was confirmed through spectral analysis and it has an active site to react with the synthesized uracil acetamide to afford the corresponding arylidene cellulosic MDAU(4), the latter compound which can easily due to presence of active CH=group behind a cyano group react with nitrogen nucleophile's and cyclized with hydrazine hydrate to give pyrazole cellulosic MDPA(5). The spectral analysis of the obtained cellulosic derivatives was confirmed with FT-IR, NMR, and SEM. Additionally, a neutral red uptake analysis has been used to investigate the cytotoxic activity of the cellulosic compounds MDAC(2), MDAU(4), and MDAP(5) against the cancer cells A549 and Caco2. After 48 h, Compound MDAU(4) had a stronger inhibitory effect on the growth of A549 and Caco2, compared to standard values. Then, using QRT-PCR, the appearance sites of the genes -Catenin, c-Myc, Cyclin D1, and MMP7 in A549 cells were examined. By reducing the expression levels of the Wnt signaling cascade genes -Catenin, c-Myc, Cyclin D1, and MMP7 when administered to A549 cells, compound MDAU(4) was shown in this investigation to be a viable candidate compared to lung cancer. Additionally, docking simulation was used to explore the uracil cellulosic heterocycles attached to different proteins, and computational investigations of these compounds looked at how well their physical characteristics matched the outcomes of their experiments.

Antioxidant activity of novel nitrogen scaffold with docking investigation and correlation of DFT stimulation

Heterocyclic scaffolds are frequently employed in drug development to treat a variety of conditions, including cancers. These substances have the ability to engage covalently or non-covalently with particular residues in the target proteins, inhibiting them. In this study, the formation of N-, S-, and O-containing heterocycles by the interaction of chalcone with nitrogen-containing nucleophiles such as hydrazine, hydroxyl amine, guanidine, urea, and aminothiourea was explored. FT-IR, UV-visible, NMR, and mass spectrometric studies were used to confirm the heterocyclic compounds that were produced. These substances were tested for their antioxidant activity by their capacity to scavenge the artificial radicals 2,2-diphenyl-1-picrylhydrazyl (DPPH). The strongest antioxidant activity was demonstrated by compound 3 (IC₅₀ = 93.4 μM), whereas compound 8 (IC₅₀ = 448.70 μM) had the lowest activity when compared to vitamin C (IC₅₀ 141.9 μM). Also, the experimental findings and the docking estimation of these heterocyclic compounds with PDBID:3RP8 were in agreement. Additionally, the compounds' global reactivity characteristics, such as HOMO-LUMO gaps, electronic hardness, chemical potential, electrophilicity index, and Mulliken charges, were identified using DFT/B3LYP/6-31G(d,p) basis sets. The two chemicals that displayed the best antioxidant activity also had their molecular electrostatic potential (MEP) ascertained using DFT simulations.

Microwave-assisted synthesis, antioxidant activity, docking simulation, and DFT analysis of different heterocyclic compounds

In this investigation, pressure microwave irradiation was used to clarify the activity of 1-(2-hydroxyphenyl)-3-(4-methylphenyl)prop-2-en-1-one (3) towards several active methylene derivatives utilized the pressurized microwave irradiation as green energy resource . Chalcone 3 was allowed to react with ethyl cyanoacetate, acetylacetone, and thioglycolic acid; respectively, at 70 °C with pressure under microwave reaction condition to afford the corresponding 2-hydroxyphenylcyanopyridone, 2-hydroxyphenyl acetylcyclohexanone, and thieno[2,3-c]chromen-4-one derivatives respectively. Moreover, the reaction of chalcone 3 with hydrogen peroxide with stirring affords the corresponding chromen-4-one derivative. All the synthesized compounds were confirmed through spectral tools such as FT-IR, ¹HNMR, ¹³CNMR, and mass spectrum. Furthermore, the synthesized heterocycles were exhibited excellent antioxidant activity and comparable with vitamin C, where the presence of the OH group increases the scavenger radical inhibition. Furthermore, the biological activity of compound 12 was demonstrated through molecular docking stimulation using two proteins, PDBID: 1DH2 and PDBID: 3RP8, which showed that compound 12 possesses greater binding energy and a shorter bond length comparable with ascorbic acid. Also, the compounds were optimized through DFT/B3LYP/6-31G (d,p) basis set and identification of their physical descriptors, whereas the compound 12 was confirmed through X-Ray single structure with Hirsh field analysis of the compound to know the hydrogen electrostatic bond interaction, and correlated with the optimized structure by comparing their bond length, bond angle, FT-IR, and NMR, which gave excellent correlation.

Synthesis, antimicrobial and molecular docking study of structural analogues of 3-((5-(dimethylcarbamoyl)pyrrolidin-3-yl)thio)-6-(1-hydroxyethyl)-4-methyl-7-oxo-1-azabicyclo[3.2.0]heptane-2-carboxylic acid

The goal of the current work was to create structural analogues of a beta lactam antibiotic that might be possibly effective against bacterial resistant strains. FTIR, 1H NMR, 13C NMR, and CHNS analyses were used to perform the spectroscopic study on the compounds M1-8. The effects of the aforementioned substances on gram-positive and gram-negative bacterial strains were investigated. Most of the eight compounds had antibacterial activity that was lower than or equivalent to that of the original medication, but two molecules, M2 and M3, surprisingly, had stronger antibacterial activity. The findings of synthesized analogues against alpha-glucosidase and DPPH inhibition were found to be modest, whereas M2, M3, and M7 strongly inhibited the urease. To comprehend the potential mode of action, a molecular docking research was conducted against urease and -amylase. The research may help in the quest for novel chemical compounds that would be effective against bacteria that are resistant to antibiotics.

Research progress on the synthesis and pharmacology of 1,3,4-oxadiazole and 1,2,4-oxadiazole derivatives: a mini review

Oxadiazole is a five-membered heterocyclic compound containing two nitrogen atoms and one oxygen atom. The 1,3,4-oxadiazole and 1,2,4-oxadiazole have favourable physical, chemical, and pharmacokinetic properties, which significantly increase their pharmacological activity via hydrogen bond interactions with biomacromolecules. In recent years, oxadiazole has been demonstrated to be the biologically active unit in a number of compounds. Oxadiazole derivatives exhibit antibacterial, anti-inflammatory, anti-tuberculous, anti-fungal, anti-diabetic and anticancer activities. In this paper, we report a series of compounds containing oxadiazole rings that have been published in the last three years only (2020–2022) as there was no report or their activities described in any article in 2019, which will be useful to scientists in research fields of organic synthesis, medicinal chemistry, and pharmacology.

Synthesis, antimicrobial, anti-proliferative activities, molecular docking and DFT studies of novel pyrazolo[5,1-c][1, 2, 4]triazine-3-carboxamide derivatives

In this investigation, we studied the reactivity of 5-aminouracil (1) with ethyl cyanoacetate (2) utilizing microwave irradiation to afford the corresponding 2-cyano-N-(2,4-dioxo-1,2,3,4-tetrahydropyrimidin-5-yl)acetamide (3) in excellent yield. The electrophilic azo-coupling reaction of acetamide 3 with aromatic diazonium salts afforded the corresponding hydrazone derivatives 4a-d. The Michael addition cyclization of hydrazone in pyridine to give pyrazolo[5,1-c][1, 2, 4]triazine-3-carboxamide 5a-d derivatives. The obtained compounds were elucidated against antimicrobial activity and antitumor activity breast cancer cells (MCF-7) and liver cancer cells (HepG2) utilized MTT assay. Compounds 5b, 5c and 5d revealed more inhibitory influence on MCF7 and HepG2 growth than the reference drug doxorubicin (Dox) after 48 h incubation. Furthermore, molecular docking studies were carried out on one of the most effective compound 4-amino-N-(2,4-dioxo-1,2,3,4-tetrahydropyrimidin-5-yl)-7-(4-fluorophenyl) pyrazole [5,1-c][1, 2, 4]triazine-3-carboxamide (5c) (TFC) with (PDB: 3t88), (PDB: 2wje) , (PDB: 4ynt), (PDB: 1tgh), (PDB: 4hdq) and (PDB: 3pxe) which attached with different proteins with different energies and shortage bond distance. Also; the comprehensive theoretical and experimental mechanical studies of compound TFC and TMC were compatible with FTIR and ¹H NMR spectral data. The optimized molecular structure of TFC with FTIR was examined via DFT/ B3LYP/6-31G (d) level.Communicated by Ramaswamy H. Sarma.