New synthesis and anti-HIV and antiviral properties of 3-arylsulfonyl derivatives of 4-ydroxycoumarin and 4-hydroxyquinolone

Design and Synthesis of Novel Coumarin Conjugated Acetamides as Promising Anticancer Agents: An In Silico and In Vitro Approach

BACKGROUND

Coumarin and benzophenone possess a vast sphere of biological activities, whereas thiazoles display various pharmacological properties. Hence, present study focused on the incorporation of coumarin and thiazole core to the benzophenone skeleton to enhance the bioactivity, anticipating their interesting biological properties.

OBJECTIVE

The objective of the current work is the synthesis and biological evaluation of a novel series of coumarin fused thiazole derivatives.

METHODS

A novel series of coumarin conjugated thiazolyl acetamide hybrid derivatives were synthesized by a multistep reaction sequence and were characterized by the FT-IR, LCMS, and NMR spectral techniques. The newly synthesized compounds were screened for anti-cancer activity by in silico and in vitro methods. The cytotoxicity of the synthesized unique compounds was executed for two different cancer cell lines, MCF-7 (Breast cancer) and KB (Oral cancer), in comparison with standard paclitaxel by MTT assay.

RESULTS

The compound 7f is a potent motif with an acceptable range of IC₅₀ values, for anti-cancer activity, i.e., 63.54μg/ml and 55.67μg/ml, against the MCF-7 and KB cell lines, respectively. Molecule docking model revealed that this compound formed three conventional hydrogen bonds with the active sites of the amino acids, MET 769, ARG 817, and LYS 721.

CONCLUSION

Compound 7f with two methyl groups on the phenoxy ring and one 4-position methoxy group on the benzoyl ring, showed a significant cytotoxic effect. An advantageous level of low toxicity against normal cell line (L292) by MTT assay was determined.

Direct synthesis of 4-hydroxycoumarins and 4-hydroxy-6-methyl-2-pyrone containing chroman-4-ones via a silver catalyzed radical cascade cyclization reaction

A novel AgNO3/K2S2O8 catalyzed radical cascade cyclization reaction of 2-(allyloxy)arylaldehydes with 4-hydroxycoumarins and 4-hydroxy-6-methyl-2-pyrone produces two new series of chroman-2-ones.

Synthesis, characterization and biological investigations of potentially bioactive heterocyclic compounds containing 4-hydroxy coumarin

In this paper, we have reported the synthesis of a series of heterocyclic azo dyes containing 4-hydroxy coumarin by diazo-coupling reaction. The structural aspect of the newly synthesized compounds was accomplished by various physico-chemical techniques like UV-Visible, FT-IR, NMR, and mass spectrometry. The computational calculations and geometrical optimization of the newly synthesized azo dyes were investigated by using Gaussian software with the help of Density functional theory (DFT)/B3LYP method using 6-31G(d,p) basis set at gaseous phase. Also, the quantum chemical parameters were evaluated to understand the structural activity concept of the dyes. The pharmacological efficacy of the azo dyes was investigated by antimicrobial, antitubercular, DNA cleavage and in silico molecular docking studies. All the newly synthesized compounds were able to exhibit significant inhibitory activity against tested microbes. Further, the in silico molecular docking showed effective binding properties of the compounds against RpsA target receptor.

tert-Butylhydroperoxide (TBHP) mediated oxidative cross-dehydrogenative coupling of quinoxalin-2(1H)-ones with 4-hydroxycoumarins, 4-hydroxy-6-methyl-2-pyrone and 2-hydroxy-1,4-naphthoquinone under metal-free conditions

We report an efficient and atom-economical method of C-3 functionalization of quinoxalin-2(1H)-ones with 4-hydroxycoumarins, 4-hydroxy-6-methyl-2-pyrone, and 2-hydroxy-1,4-naphthoquinone via the free radical cross-coupling pathway under metal-free conditions. tert-Butylhydroperoxide (TBHP) smoothly promotes the reaction furnishing the cross-dehydrogenative coupling (CDC) products in very good to excellent yields. The protocol neither uses any toxic reagents nor metal catalysts to carry out the reaction, and all the products have been obtained without column chromatography purification. Different radical trapping experiments with 2,2,6,6-tetramethylpiperidine-1-oxyl, butylated hydroxytoluene, and diphenyl ethylene confirm the involvement of radicals.

The molecular diversity scope of 4-hydroxycoumarin in the synthesis of heterocyclic compounds via multicomponent reactions

4-Hydroxycoumarins are some of the most versatile heterocyclic scaffolds and are frequently applied in the synthesis of various organic compounds. 4-Hydroxycoumarin-based compounds are important among heterocyclic structures due to their biological and pharmaceutical activities. In this study, we provide an overview on the recent applications of 4-hydroxycoumarin in multicomponent reactions for the synthesis of various heterocyclic compounds during the time period of 2015-2018.

Dicoumarol derivatives: Green synthesis and molecular modelling studies of their anti-LOX activity

Dicoumarol derivatives were synthesized in the InCl3 catalyzed pseudo three-component reactions of 4-hydroxycoumarin with aromatic aldehydes in excellent yields. The reactions were performed in water under microwave irradiation. All synthesized compounds were characterized using NMR, IR, and UV-Vis spectroscopy, as well as with TD-DFT. Obtained dicoumarols were subjected to evaluation of their in vitro lipid peroxidation and soybean lipoxygenase inhibition activities. It was shown that five of ten examined compounds (3e, 3h, 3b, 3d, 3f) possess significant potential of antilipid peroxidation (84-97%), and that compounds 3b, 3e, 3h provided the highest soybean lipoxygenase (LOX-Ib) inhibition (IC50 = 52.5 µM) and 3i somewhat lower activity (IC50 = 55.5 µM). The bioactive conformations of the best LOX-Ib inhibitors were obtained by means of molecular docking and molecular dynamics. It was shown that, within the bioactive conformations interior to LOX-Ib active site, the most active compounds form the pyramidal structure made of two 4-hydroxycoumarin cores and a central phenyl substituent. This form serves as a spatial barrier which prevents LOX-Ib Fe2+/Fe3+ ion activity to generate the coordinative bond with the C13 hydroxyl group of the α-linoleate. It is worth pointing out that the most active compounds 3b, 3e, 3h and 3i can be candidates for further examination of their in vitro and in vivo anti-inflammatory activity and that molecular modeling study results provide possibility to screen bioactive conformations and elucidate the mechanism of dicoumarols anti-LOX activity.

“On water” synthesis of highly functionalized 4H-chromenes via carbon–carbon bond formation under microwave irradiation and their antibacterial properties

Microwave assisted synthesis catalyst-free synthesis water as a solvent anti bacterial properties.

Synthesis, antibacterial activities, and theoretical studies of dicoumarols

In this work, we report the synthesis, evaluation of antibacterial activity and theoretical study of dicoumarols including DC, 2-PyDC, 3-PyDC and 4-PyDC.

Practical synthesis of hydroxychromenes and evaluation of their biological activity

A simple and efficient seven steps synthesis of brodifacoum and difethialone from phenylacetyl chloride is described. The key synthetic strategies involve Friedel-Crafts acylation, intramolecular ring cyclization and condensation reaction in the presence of Brønsted-Lowry acids. It was found that brodifacoum showed favorable inhibiting activities on LPS-stimulated nitrite production in BV-2 microglia cells. Brodifacoum exhibited superior anti-inflammatory effects than difethialone. We expect that an efficient linear synthesis of 4-hydroxycoumarin derivatives and key fragments that are useful agents for the modulation of inflammation as well as inhibition of coagulation will be of practical use.

Synthetic Approaches and Biological Activities of 4-Hydroxycoumarin Derivatives

The main purpose of this review is to summarize recent chemical syntheses and structural modifications of 4-hydroxycoumarin and its derivatives, of interest due to their characteristic conjugated molecular architecture and biological activities.