The application of isocyanide-based multicomponent reactions for triterpenoid functionalization is few reported. Triterpenoids and their derivatives are an important class of natural products due to their potential applications as antibacterial, antifungal, and cytotoxic agents. Herein, we describe the use of ethanol as solvent in the Passerini reaction for the functionalization of masticadienonic acid isolated from fruits and peduncles of P. mexicana. A small series of α-acyloxycarboxamides was synthesized with moderate yields of 33 to 57%, evaluating and extending the scope of the aldehyde component.

Introduction

Currently, in the development of new biologically active compounds, a trend is developing towards the concept of molecular hybridization, which consists in combining two or more pharmacophoric fragments in one molecule. From this point of view, chromen-4(4H)-ones and furan-2(3H)-ones are promising starting compounds.

Experimental details

3-{[2-Oxo-5-arylfuran-3(2H)-ylidene]methyl}-4H-1-benzopyran-4-ones were synthesized by the reaction of equimolar amounts of 5-arylfuran-2(3H)-ones with 3-formylchromone in glacial acetic acid with good yields. The composition and structure of all compounds were characterized by a set of spectroscopic methods (IR, NMR).

Results and Discussion

By screening various reaction conditions, we found that using the Monowave 50 reactor resulted in increased product yields as well as significantly improved reaction efficiency Based on NMR, it was shown that the resulting compounds exist only in the form of E-isomers.

Lassa fever is an animal-borne, or zoonotic, acute viral hemorrhagic illness caused by Lassa virus, a member of the arenavirus family of viruses. There is currently no licensed vaccine for Lassa fever, but several potential vaccines are in development. However, there is still a need for a safe treatment with proven efficacy and a range of potential treatments. In both viral RNA synthesis and immunological suppression, the Lassa virus' nucleoprotein (NP) plays a crucial roles. An arenaviral NP that demonstrates surprising capabilities and suggests particular mechanisms for immune evasion and cap binding. These discoveries have a lot of potential for therapeutic development. Based on chemoinformatics approach, we focused on designing a computational drug for the targeting of viral nucleoprotein of human pathogenic Lassa fever virus. We accomplished several vital steps including target protein and ligand identification and refinement, active site analysis, ADMET analysis, molecular docking, protein-ligand interaction analysis, etc. We retrieved Lassa viral nucleoprotein receptor from widely used RSCB PDB website as well as control ligand molecules includings Arbidol, Ribavirin, Favipiravir, UTP (Uridine 5'-Triphosphate) from significant chemical database Pubchem. ADMET property analysis by SwissAdme and pkCSM server, molecular docking study done by PyRx virtual screening tools, and Discovery studio used for further protein-ligand interaction analysis. We found a very significant molecular binding affinity score that promises the designed drug is more stable and reliable. However, it will demand to be considered considerably in vivo and in vitro experimental drug design models.

The use of heterogeneous catalytic systems in the production of esters of secondary alcohols (monoterpenic and steroidal) allows obtaining satisfactory yields of these derivatives widely used in the industry.
The use of the heterogeneous system uranyl acetate / chloroform, under laboratory conditions, allows to reach yields higher than 90 %, optimizing the purification steps and without the use of extreme conditions (inert atmosphere, high temperatures or corrosive agents). All compounds were characterized by the use of spectroscopic techniques.

Hantzsch 1,4-dihydropyridines (Hantzsch 1,4-DHP), first described in 1882, have been extensively utilised as the analogs of NAD(P)H coenzymes to study the mechanism and synthetic-pharmacological potential of various redox processes. In addition, several 1,4- DHP based drugs, such as Nifedipine, Niguldipine, Amlodepine besylate have been recognised as calcium channel blockers for the treatment of cardiovascular diseases, including hypertension. Both during the redox processes and in the course of drug metabolism, 1,4-DHP systems are oxidatively transformed into the corresponding pyridine derivatives. Furthermore, the oxidation of readily accessible Hantzsch 1,4-DHP constitutes the more accesible, at laboratory scale, method to obtain pyridine derivatives with a great spectrum of important properties. Pyritic ashes, a waste material from the metallurgical industry, present a varied composition and multiple phases with potential catalytic activity. Taking into account that the use of some catalytic agents and conditions for the oxidative aromatization of dihydropyridines results in low yields and tedious separation processes, the use of pyritic ash can facilitate the obtaining of derivatives from dihydropyridines under sustainable conditions.

This report describes the preliminary characterization of pyritic ashes and their use as a catalyst for the aromatization process of dihydropyridines. the results allow to corroborate the effectiveness of this industrial waste as a catalyst. All the synthesized derivatives were characterized by NMR and XRD techniques.

Parkinson's disease (PD) is the second most common neurodegenerative chronic disorder in the older people, caused by the loss of dopaminergic neurons in the brain, which leads to the dopamine depletion. Among its symptoms (resting tremor, rigidity, dementia...). Monoamine oxidase B (MAO-B) is a key enzyme in PD. The inhibition of it increases the level of dopamine in the brain by preventing its degradation, especially in the early stages of the disease.

In the present work, we combined molecular docking with ADME analysis of a new class of ten derivatives of indanone in order to reduce the metabolic depletion of dopamine through inhibiting the MAO-B.

A molecular docking study was performed to clarify bonding modes and affinities between the active site residues of MAO-B with the new class derivatives of indanone, followed by the ADME prediction to check the druglikeness properties of the best ligands obtained using the method above.

Molecular docking results show that the ligands: L3 and L5 present a high negative score energy (-8.809 kcal/mol, -9.276 kcal/mol) respectively with a good RMSD values (1.419Å, 1.560 Å) respectively. Moreover, the ADME prediction gave promising results that those ligands have an oral bioavailability and a high level of gastrointestinal absorption, which means they can be good inhibitors against Parkinson's disease.

Aromatic ketones are important compounds because of their utility as synthetic intermediates, because they have importan applications as light absorbing compounds and for the biological activities, for instance. Suzuki coupling reaction is a C-C bond forming procedure catalyzed by palladium species under a basic medium. In this reaction, a halide or pseudohalide reacts with electrophiles and a zerovalent palladium specie (nucleophile) initiates the catalytic cycle. Bifonazole (antifungal) and Ketoprofen (antinflamatory) are commercial drugs having aryl ketones as synthetic intermediates. Acyl chlorides can be used as electrophiles in Suzuki-Miyaura cross-couplings and, in this case, their reaction with arylboronic acids results in aryl ketones. Considering the synthesis of intermediates that can generate the medicines mentioned above as well as their analogous, in this work, selectivity in Suzuki coupling reactions between acid chlorides and boronic acids, the catalytic system for such reactions and other aspects such as the use of conventional heating or microwave irradiation are studied. Intermediates of interest are: 4-bromobenzophenone, 4-phenylbenzophenone and 3-bromobenzophenone.

Abstract: In this study, we have characterized the pectin extracted from peels of Algerian Citrus sinensis and evaluated its antibacterial action, its antioxidant activity and its anticoagulant effect. Pectin was extracted under acidic conditions using hydrochloric acid for PCT-1 and citric acid for PCT-2 and determined their physicochemical properties by Fourier Transformed Infrared spectroscopy (FTIR), X-ray powder diffraction (PXRD), differential scanning calorimetry (DSC), yield, degree of methylation, water content and ash content. In addition, the FTIR results showed desired banding characteristics, and their thermal properties evaluated by DSC showed that the thermal degradation was around 240°C. XRD results showed that PCT-1 and PCT-2 were amorphous and have similar characteristics with commercial pectin. On the other hand, the antibacterial action showed that PCT-1 and PCT-2 have no effect on Pseudomonas aeruginosa and E. coli bacteria, unlike Staphylococcus epidermidis, where it showed considerable antibacterial action [1]. The antioxidant activity of PCT-1 and PCT-2 was observed by 2,2 diphenyl-1-picrylhydrazyl (DPPH) method, the absorbance values recorded for PCT-1 and PCT-2 confirmed their antioxidant potential explained by the presence of several free hydroxyl groups in PCT-1 and PCT-2 structure. On the other hand, our findings indicate that PCT-1 and PCT-2 don’t have a marked anticoagulant effect, but have acceptable potential and can be used as anticoagulants for the treatment of thrombotic diseases with fewer side effects compared to the widely used heparin. These results suggest that pectin from peels of Algerian Citrus sinensis has potential properties as biomaterial for several biomedical applications.

This paper is covered up with the comparative studies of ortho, meta and para substituted benzaldehyde using computational chemistry. We have first optimized the structures of titled chloro benzaldehyde by using Gaussian 09 software with the B3LYP/631-G (d,p) basis set. The titled compound's polarizability and hyper-polarizability values have been computed, along with an examination of its non-linear optical characteristics. The titled molecule's total initial static hyper-polarizability as determined by DFT may be a topic for future NLO content that is appealing.

Carbon-based nanomaterials, particularly carbon dots (C-dots) have emerged as outstanding candidates for several areas such as biomedicine, (bio)sensors, photocatalysis, optoelectronics and bioimaging, due to their excellent luminescence, photostability, small size, low cytotoxicity, and biocompatibility.

C-dots can be prepared by several procedures (top-down and bottom-up methods), using various carbon sources. Bottom-up green approaches based on the use of renewable biomass precursors for producing C-dots are particularly attractive since an effective reduction of environmental impacts of those wastes can be foreseen, while high-valued nanomaterials can be obtained, contributing to a circular economy.

In this work, we highlight recent green synthesis of C-dots from Porphyridium cruentum biomass, a red marine microalga, expecting that the
as-synthesized nanoparticles have good luminescence, biocompatibility, and antioxidant capabilities. The obtained nanomaterials were characterized regarding surface functional groups by FTIR spectroscopy and optic properties using UV-Vis and fluorescence spectroscopies. Antioxidant properties were explored through the ABTS assay, and their cytotoxicity was evaluated against Vero and HeLa cell-lines.

Fluorescence microscopy images were acquired and showed that C-dots have good interaction with the cell plasma membrane, encouraging their use on bioimaging.