Pharmacological evaluation of 9,10-dihydrochromeno[8,7-e][1,3]oxazin-2(8H)-one derivatives as potent anti-inflammatory agent

Design, synthesis of benzimidazole tethered 3,4-dihydro-2H-benzo[e] [1, 3] oxazines as anticancer agents

A series of novel 3-(1H-benzo[d]imidazol-2-yl)-3,4-dihydro-2H-benzo[e][1,3] oxazine analogues synthesized through a two-step synthetic protocol. The structure of the compounds were established by interpretation 1H NMR, 13C NMR and Mass spectral data recorded after purification. All the title compounds 4a-k were screened for their in vitro anti-cancer activity against two breast cancer cell lines MCF 7 and MDA-MB-231 by using Doxorubicin as standard reference. Compound 4e displayed superior activity against both the cell lines MCF-7 and MDA-MB-231 with IC50 values of 8.60 ± 0.75 and 6.30 ± 0.54 µM respectively, compared to the Doxorubicin IC50 value of 9.11 ± 0.54 and 8.47 ± 0.47 µM. Compound 4i also indicated good activity with IC50 value of 9.85 ± 0.69 μM on par with Doxorubicin against MCF-7 cells. Compound 4g demonstrated best activity on par with standard reference to IC50 value of 8.52 ± 0.62 μM against MDA-MB-231 cell line. And all other compounds demonstrated good to moderate activity compared to Doxorubicin. Docking studies against EGFR showed that all the compounds have very good binding affinities towards the target. The predicted drug-likeness properties of all compounds enable them to be used as therapeutic agents.

Umbelliferone and Its Synthetic Derivatives as Suitable Molecules for the Development of Agents with Biological Activities: A Review of Their Pharmacological and Therapeutic Potential

Umbelliferone (UMB), known as 7-hydroxycoumarin, hydrangine, or skimmetine, is a naturally occurring coumarin in the plant kingdom, mainly from the Umbelliferae family that possesses a wide variety of pharmacological properties. In addition, the use of nanoparticles containing umbelliferone may improve anti-inflammatory or anticancer therapy. Also, its derivatives are endowed with great potential for therapeutic applications due to their broad spectrum of biological activities such as anti-inflammatory, antioxidant, neuroprotective, antipsychotic, antiepileptic, antidiabetic, antimicrobial, antiviral, and antiproliferative effects. Moreover, 7-hydroxycoumarin ligands have been implemented to develop 7-hydroxycoumarin-based metal complexes with improved pharmacological activity. Besides therapeutic applications, umbelliferone analogues have been designed as fluorescent probes for the detection of biologically important species, such as enzymes, lysosomes, and endosomes, or for monitoring cell processes and protein functions as well various diseases caused by an excess of hydrogen peroxide. Furthermore, 7-hydroxy-based chemosensors may serve as a highly selective tool for Al3+ and Hg2+ detection in biological systems. This review is devoted to a summary of the research on umbelliferone and its synthetic derivatives in terms of biological and pharmaceutical properties, especially those reported in the literature during the period of 2017-2023. Future potential applications of umbelliferone and its synthetic derivatives are presented.

Development of Combretastatin A-4 Analogues as Potential Anticancer Agents with Improved Aqueous Solubility

Combretastatin A-4 (CA-4) is a potent tubulin polymerisation inhibitor. However, the clinical application of CA-4 is limited owing to its low aqueous solubility and the easy conversion of the olefin double bond from the more active cis- to the less active trans-configuration. Several structural modifications were investigated to improve the solubility of CA-4 derivatives. Among the compounds we synthesized, the kinetic solubility assay revealed that the solubility of compounds containing a piperazine ring increased the most, and the solubility of compounds 12a1, 12a2, 15 and 18 was increased 230-2494 times compared with that of the control compound (Z)-3-(4-aminophenyl)-2-(3,4,5-trimethoxyphenyl)acrylonitrile (9a). In addition, these synthesised stilbene nitriles had high anticancer cell (AGS, BEL-7402, MCF-7, and HCT-116) selectivity over L-02 and MCF-10A normal cells while maintaining micromolar activity against cancer cells. The most cytotoxic compound is 9a, and the IC50 value is 20 nM against HCT-116 cancer cells. Preliminary studies indicated that compound 12a₁ had excellent plasma stability and moderate binding to rat plasma proteins, suggesting it is a promising lead compound for the development of an anticancer agent.

Synthesis of new coumarin[1,3]oxazine derivatives of 7-hydroxy-6-isobornyl-4-methylcoumarin and their antioxidant activity

In this work, we synthesized a series of new 9,10-dihydro-2H,8H-chromeno[8,7e][1,3]oxazine-2-on derivatives which incorporate isobornylcoumarin and 1,3-oxazine moieties. A structure-antioxidant activity relationship was analyzed. A comparative evaluation of their radical scavenging activity, antioxidant and membrane-protective properties was carried out in test with DPPH, as well as on the models of Fe²⁺ /ascorbate-initiated lipid peroxidation and oxidative hemolysis of mammalian red blood cells. The results suggest that all the obtained coumarin[1,3]oxazine derivatives of 7-hydroxy-6-isobornyl-4-methylcoumarin are capable of exhibiting antioxidant activity in various model systems. Compound 7 with a phenyl fragment, combining high radical scavenging activity and the ability to inhibit Fe²⁺ /ascorbate-initiated peroxidation of animal lipids in a heterogeneous environment, also proved to be the most effective membrane protector and antioxidant in the model of H₂ O₂ -induced erythrocyte hemolysis.

Tandem CuAAC/Ring Cleavage/[4 + 2] Annulation Reaction to Synthesize Dihydrooxazines and Conversion to 2-Aminopyrimidines

A tandem CuAAC/ring cleavage/[4 + 2] annulation reaction of terminal ynones, sulfonyl azides, and oximes has been developed to synthesize functionalized dihydrooxazines under mild conditions. In particular, intermediate N-sulfonyl acylketenimines are the first example of a 4π-system participating in [4 + 2] cycloadditions, and dihydrooxazines can convert to 2-aminopyridines through ring cleavage under basic conditions.