Synthesis and Structure−Activity Relationships of New Benzodioxinic Lactones as Potential Anticancer Drugs

New and promising type of leukotriene B4 (LTB4) antagonists based on the 1,4-benzodioxine structure

New leukotriene B4 (LTB4) antagonists have been synthesized that can be considered as potential anti-inflammatory drugs. Structures containing the dioxygenated nucleus of 1,4-benzodioxine constitute a potential group of leukotriene B4 (LTB4) antagonists. The objective of this study was to access efficient and selective LTB4 antagonists as a way to elucidate the role of LTB4 in inflammatory processes and therefore allow the development of new types of structures based on 1,4-benzodioxine. Forty-one new 1,4-benzodioxine molecules substituted at different positions of the heterocyclic nucleus were synthesized to determine the minimum structural requirements by studying structure-activity relationships. Eighteen of them were tested in vitro and in vivo for their anti-inflammatory activity related to the antagonist character of LTB4. Pharmacological tests have shown satisfactory in vitro activity for compounds 24b, 24c and 24e with IC50's of 288, 439, 477 nM respectively. The results of the in vivo tests, carried out with the compound that presented greater activity in the in vitro tests 24b, have shown significant anti-inflammatory properties.

A new mode of cyclobutenedione ring opening for the synthesis of 2-oxobut-3-enamides and tetrasubstituted furans

A dichotomy between the additions of organolithiums and lithium amides to cyclobutenediones is described wherein the former give carbonyl addition products while the latter induce ring opening by enone cleavage via O- to C-lithium transfer. This distinct mode of ring scission gives access to 2-oxobut-3-enamides and tetrasubstituted furans.

Synthesis of N-2(5H)-furanonyl sulfonyl hydrazone derivatives and their biological evaluation in vitro and in vivo activity against MCF-7 breast cancer cells

A series of (E)-N-2(5H)-furanonyl sulfonyl hydrazone derivatives have been rationally designed and efficiently synthesized by one-pot reaction with good yields for the first time. This green approach with wide substrate range and good selectivity can be achieved at room temperature in a short time in the presence of metal-free catalyst. The cytotoxic activities against three human cancer cell lines of all newly obtained compounds have been evaluated by MTT assay. Among them, compound 5 k exhibits high cytotoxic activity against MCF-7 human breast cancer cells with an IC₅₀ value of 14.35 μM. The cytotoxic mechanism may involve G2/M phase arrest pathway, which is probably caused by activating DNA damage. Comet test and immunofluorescence results show that compound 5 k can induce DNA damage in time- and dose-dependent manner. Importantly, 5 k also can effectively inhibit the proliferation of MCF-7 cells and angiogenesis in the zebrafish xenograft model. It is potential to further develop N-2(5H)-furanonyl sulfonyl hydrazone derivatives as potent drugs for breast cancer treatment with higher cytotoxic activity by modifying the structure of the compound.

Berberine as Source of Antiproliferative Hybrid Compounds: In Vitro Antiproliferative Activity and Quantitative Structure-activity Relationship

BACKGROUND

Despite advances for cancer treatment, it still remains a major worldwide public health problem. Compounds derived from natural sources are important alternatives to combat this mortal disease. Berberine is an isoquinoline alkaloid with a wide variety of pharmacological properties, including antiproliferative activity. Previously, we have found that fatty acids also show antiproliferative activity against cancer cell lines..

OBJECTIVE

To combine berberine and fatty acids, or carboxylic acids, in order to improve their antiproliferative properties.

METHODS

We synthetized six new hybrid derivatives through a simple methylenedioxy group-cleavage method followed by the reaction with fatty acids, or carboxylic acids. The structure of the compounds was elucidated by IR, NMR and HRMS. The in vitro antiproliferative activity against four human cancer cell lines (HeLa, A-549, PC-3 and LS-180) and one normal cell line (ARPE-19), was evaluated by the MTT method. Chemical structures were drawn using SPARTAN '08 software and the conformational analysis was carried out with a molecular mechanic level of theory and the SYBIL force field. All molecular structures were subjected to geometrical optimization at the semi-empirical method PM3. Molecular descriptors were calculated using DRAGON 5.4 and SPARTAN ´08 programs.

RESULTS

The geranic acid and berberine hybrid compound (6) improved the antiproliferative activity shown by natural berberine, even more than the 16- to 18-carbon atoms fatty acids. Compound 6 showed IC50 values of 2.40 ± 0.60, 1.5 ± 0.24, 5.85 ± 1.07 and 5.44 ± 0.24 μM, against HeLa, A-549, PC-3 and LS-180 human cancer cell lines, respectively. Using this information, we performed a quantitative structure-activity relationship (QSAR) of the hybrid molecules and found that the molecular descriptors associated with the antiproliferative activity are: hydrophobic constant associated with substituents (π(A) = 6.5), molecular volume descriptor (CPKvolume≈ 700 Å3), EHOMO, number of rotatable bonds (RBN) and number of 6-membered rings (nR06).

CONCLUSION

The methylendioxy and methoxyl groups in berberine are important for the antiproliferative activity shown by its derivatives. Better results in antiproliferative activity were obtained in compound 6 with the prenyl moiety. The QSAR indicates that the molecular descriptors which associated positively with the antiproliferative activity are: hydrophobic constant associated with substituents (π(A) = 6.5), molecular volume descriptor (CPKvolume≈ 700 Å3) and EHOMO. This research gave the basis for the design and preparation of new, easily afforded molecules derived from berberine and carboxylic acids, with improved antiproliferative activity.

Multigram scale synthesis of polycyclic lactones and evaluation of antitumor and other biological properties

An efficient four-step synthesis of tetracyclic lactones from 1,4-benzodioxine-2-carboxylic acid was developed. Ellipticine derivatives exhibit antitumor activity however only a few derivatives without carbazole subunit have been studied to date. Herein, several tetracyclic lactones were synthesized and biologically evaluated. Several compounds (2a, 3a, 4a and 5a) were found to be inhibitors of the Kras-Wnt pathway. The lactone 2a also exerted a potent inhibition of Tau protein translation and was shown to have capacity for CYP1A1-bioactivation. The results obtained are further evidence of the therapeutic potential of tetracyclic lactones related to ellipticine. Molecular modeling studies showed that compound 2a is inserted between helix α3 and α4 of the KRas protein making interactions with the hydrophobic residues Phe90, Glu91, Ile9364, Hie94, Leu133 and Tyr137and a hydrogen bond with residue Arg97.

Modeling the Antileukemia Activity of Ellipticine-Related Compounds: QSAR and Molecular Docking Study

The antileukemia cancer activity of organic compounds analogous to ellipticine representes a critical endpoint in the understanding of this dramatic disease. A molecular modeling simulation on a dataset of 23 compounds, all of which comply with Lipinski's rules and have a structure analogous to ellipticine, was performed using the quantitative structure activity relationship (QSAR) technique, followed by a detailed docking study on three different proteins significantly involved in this disease (PDB IDs: SYK, PI3K and BTK). As a result, a model with only four descriptors (HOMO, softness, AC1RABAMBID, and TS1KFABMID) was found to be robust enough for prediction of the antileukemia activity of the compounds studied in this work, with an R² of 0.899 and Q² of 0.730. A favorable interaction between the compounds and their target proteins was found in all cases; in particular, compounds 9 and 22 showed high activity and binding free energy values of around -10 kcal/mol. Theses compounds were evaluated in detail based on their molecular structure, and some modifications are suggested herein to enhance their biological activity. In particular, compounds 22_1, 22_2, 9_1, and 9_2 are indicated as possible new, potent ellipticine derivatives to be synthesized and biologically tested.

Irreversible endo-selective diels-alder reactions of substituted alkoxyfurans: a general synthesis of endo-cantharimides

The [4+2] cycloaddition of 3-alkoxyfurans with N-substituted maleimides provides the first general route for preparing endo-cantharimides. Unlike the corresponding reaction with 3H furans, the reaction can tolerate a broad range of 2-substitued furans including alkyl, aromatic, and heteroaromatic groups. The cycloaddition products were converted into a range of cantharimide products with promising lead-like properties for medicinal chemistry programs. Furthermore, the electron-rich furans are shown to react with a variety of alternative dienophiles to generate 7-oxabicyclo[2.2.1]heptane derivatives under mild conditions. DFT calculations have been performed to rationalize the activation effect of the 3-alkoxy group on a furan Diels-Alder reaction.

Induction of apoptosis by cyclobutanones and derived polycyclic γ-lactones: a preliminary analysis of antiproliferative activity

A series of cyclobutanones (7a–f) were synthesized by irradiation of β-ionone derived chalcones (4a–f) in aqueous methanol and further converted to polycyclic γ-lactones (8a–f) by Baeyer–Villiger oxidation.

Synthesis of some novel D-glucuronic acid acetylated derivatives as potential anti-tumor agents

A structurally diverse series of Δ(4,5) -uronamide derivatives have been chemically synthesized starting from D-glucuronic acid itself by means of acetylation, activation, amide bond formation and base-catalyzed elimination protocols. Structure elucidation for all products along with optimization of the synthetic steps is described. The synthesized compounds were evaluated for their in-vitro anti-tumor activity against MCF-7, TK-10 and UACC-62 cell lines. The compounds 5, 11, 13, 15 and 16 were the most active against TK-10 cell line. On the other hand, the most active compounds against the MCF-7 cell line were 11 and 15. However, compounds 5, 7, 11, 13, 15 and 16 were the most active against the UACC-62 cell line.