Synthesis of new 2-naphthyl ethers and their protective activities against DNA damage induced by bleomycin-iron

Powerful Potential of Polyfluoroalkyl-Containing 4-Arylhydrazinylidenepyrazol-3-ones for Pharmaceuticals

4-Arylhydrazinylidene-5-(polyfluoroalkyl)pyrazol-3-ones (4-AHPs) were found to be obtained by the regiospecific cyclization of 2-arylhydrazinylidene-3-(polyfluoroalkyl)-3-oxoesters with hydrazines, by the azo coupling of 4-nonsubstituted pyrazol-5-oles with aryldiazonium chlorides or by the firstly discovered acid-promoted self-condensation of 2-arylhydrazinylidene-3-oxoesters. All the 4-AHPs had an acceptable ADME profile. Varying the substituents in 4-AHPs promoted the switching or combining of their biological activity. The polyfluoroalkyl residue in 4-AHPs led to the appearance of an anticarboxylesterase action in the micromolar range. An NH-fragment and/or methyl group instead of the polyfluoroalkyl one in the 4-AHPs promoted antioxidant properties in the ABTS, FRAP and ORAC tests, as well as anti-cancer activity against HeLa that was at the Doxorubicin level coupled with lower cytotoxicity against normal human fibroblasts. Some Ph-N-substituted 4-AHPs could inhibit the growth of N. gonorrhoeae bacteria at MIC 0.9 μg/mL. The possibility of using 4-AHPs for cell visualization was shown. Most of the 4-AHPs exhibited a pronounced analgesic effect in a hot plate test in vivo at and above the diclofenac and metamizole levels except for the ones with two chlorine atoms in the aryl group. The methylsulfonyl residue was proved to raise the anti-inflammatory effect also. A mechanism of the antinociceptive action of the 4-AHPs through blocking the TRPV1 receptor was proposed and confirmed using in vitro experiment and molecular docking.

Iodine-mediated construction of polyfunctionalized arylazopyrazoles from β-ketoesters or 2-arylpyrazol-3-ones and arylhydrazines

This paper describes step-economic iodine-mediated construction of functionalized arylazopyrazoles in the presence of catalytic AgNO3 starting from simple β-ketoesters and two equivalents of arylhydrazines. This cascade reaction includes in situα-iodination of β-ketoesters, pyrazol-3-one formation, substitution with a nitrogen nucleophile, and oxidation/aromatization.

Synthesis and Characterization of Some New Coumarins with in Vitro Antitumor and Antioxidant Activity and High Protective Effects against DNA Damage

Coumarins are naturally occurring oxygen heterocyclic compounds having multifarious medicinal properties, hence used as lead compounds for designing new potent analogs. The chromene butenoic acid 3 and the benzochromene butenoic acid 4 which are derived from the reaction of glyoxalic acid with 3-acetylcoumarin and 3-acetylbenzocoumarin, respectively, were reacted with different nitrogen and carbon nucleophiles to give new heterocyclic compounds. The structures of the prepared compounds were elucidated by IR, ¹H-NMR, and mass spectroscopy. Some of the newly prepared compounds were tested in vitro against a panel of four human tumor cell lines namely; hepatocellular carcinoma (liver) HepG2, colon cancer HCT-116, human prostate cancer PC3, and mammary gland breast MCF-7. Also they were tested as antioxidants. Almost all of the tested compounds showed satisfactory activity.

Utilization of Cyanoacetohydrazide and Oxadiazolyl Acetonitrile in the Synthesis of Some New Cytotoxic Heterocyclic Compounds

A (pyridazinyl)acetate derivative was reacted with thiosemicarbazide and hydrazine hydrate to yield spiropyridazinone and acetohydrazide derivatives, respectively. The acetohydrazide derivative was used as a starting material for synthesizing some new heterocyclic compounds such as oxoindolinylidene, dimethylpyrazolyl, methylpyrazolyl, oxopyrazolyl, cyanoacetylacetohydrazide and oxadiazolylacetonitrile derivatives. The behavior of the cyanoacetylacetohydrazide and oxadiazolylacetonitrile derivatives towards nitrogen and carbon nucleophiles was investigated. The assigned structures of the prepared compounds were elucidated by spectral methods (IR, ¹H-NMR (13)C-NMR and mass spectroscopy). Some of the newly prepared compounds were tested in vitro against a panel of four human tumor cell lines, namely hepatocellular carcinoma (liver) HePG-2, colon cancer HCT-116, human prostate cancer PC3, and mammary gland breast MCF-7. Also they were tested as antioxidants. Almost all of the tested compounds showed satisfactory activity.

tert-Butyl nitrite mediated azo coupling between anilines and imidazoheterocycles

A ^tBuONO mediated practical and efficient method for the synthesis of azo imidazoheterocycles with broad functionalities has been achieved by the reaction between imidazoheterocycles and anilines at room temperature in goods yields.

Cytotoxic neviotane triterpene-type from the red sea sponge Siphonochalina siphonella

Background:

Siphonochalina siphonella is a marine sponge collected from saudi Red Sea water and scare study from this region.

Objective:

To isolate the anticancer triterpenes with potent cytotoxicity from marine sponge, Siphonochalina siphonella and state the mode of action in cancer cell lines.

Materials and Methods:

The sponge material was collected, extracted with organic solvent, and fractionated on different adsorbents. The structure of the pure metabolites were elucidated employing different spectroscopic techniques including 1D (¹H and ¹³C) and 2D (COSY, HMQC and HMBC) NMR, and MS spectroscopy.

Results:

A new Neviotine-C (1) was obtained, along with four known metabolites (2-5). All compounds, except 5, were tested towards MCF-7, PC-3 and A549 and showed effects with IC₅₀ in range 7.9-87 μM, whilst, 3 showed potent anti-proliferative activity against PC-3 and A549 with IC₅₀ = 7.9 ± 0.120 and 8.9 ± 0.010 μM, respectively.

Conclusion:

Compounds (1-4) showed significant cytotoxic activities, while 3 showed potent effect. The antiproliferative of 3 was attributed to significant S-phase cell cycle arrest.

Nucleobase-based barbiturates: their protective effect against DNA damage induced by bleomycin-iron, antioxidant, and lymphocyte transformation assay

A number of nucleobase-based barbiturates have been synthesized by combination of nucleic acid bases and heterocyclic amines and barbituric acid derivatives through green and efficient multicomponent route and one pot reaction. This approach was accomplished efficiently using aqueous medium to give the corresponding products in high yield. The newly synthesized compounds were characterized by spectral analysis (FT-IR, ¹H NMR, ¹³C NMR, HMBC, and UV spectroscopy) and elemental analysis. Representative of all synthesized compounds was tested and evaluated for antioxidant, bleomycin-dependent DNA damage, and Lymphocyte Transformation studies. Compounds TBC > TBA > TBG showed highest lymphocyte transformation assay, TBC > TBA > BG showed inhibitory antioxidant activity using ABTS methods, and TBC > BPA > BAMT > TBA > 1, 3-TBA manifested the best protective effect against DNA damage induced by bleomycin.

Synthesis and antioxidant and antitumor activity of novel pyridine, chromene, thiophene and thiazole derivatives

2-Tosylacetonitrile (1) when reacted with α,β-unsaturated nitriles 2a-c or a mixture of formaldehyde and 3-amino-2-substituted-pent-2-endinitriles 6a,b yielded pyridine derivatives 3a-c and 9a,b, respectively, while when subjected to react with salicylaldehyde yielded chromene derivatives 4 and 5, subsequently. The behavior of thiocarbamoyl derivative 10 derived from 1 towards some α-halogenated compounds have been investigated as well as its behavior towards elemental sulfur and phenyl isothiocyanate. Newly synthesized compounds were screened for their antioxidant activity, erythrocytes haemolysis and bleomycin-independent DNA damage. Some of the tested compounds exhibited promising activities.

Synthesis and antitumor evaluation of some new 1,3,4-oxadiazole-based heterocycles

The synthetic strategies and characterization of some novel 1,3,4-oxadiazole derivatives carrying different pharmacophores and heterocyclic rings that are relevant to potential antitumor and cytotoxic activities are described. The antitumor activities of the newly synthesized compounds were evaluated according to the protocol of the National Cancer Institute (NCI) in-vitro disease-oriented human cells screening panel assay. The results revealed that five compounds, namely 2, 7a, 11a, 12b, and 17; displayed promising in-vitro antitumor activity in the 4-cell lines assay. Incorporating a thiazole ring to 1,3,4-oxadiazole skeleton resulted in better antitumor activities than those displayed by the pyrazole and thiophene ring systems. Transformation of 1,3,4-oxadiazole 2 to N-(6-amino-7H-pyrazolo[5,1-c][1,2,4]triazol-3-yl)benzamide (15) diminished the antitumor activity.

Antioxidant, cytotoxic, antitumor, and protective DNA damage metabolites from the red sea brown alga Sargassum sp

Background:

Macroalgae can be viewed as a potential antioxidant and anti-inflammatory sources owing to their capability of producing compounds for its protection from environmental factors such as heat, pollution, stress, oxygen concentration, and UV radiations.

Objective:

To isolate major compounds which are mainly responsible for the pharmacological activity of brown alga under investigation, Sargassum sp.

Materials and Methods:

Algal material was air dried, extracted with a mixture of organic solvents, and fractionated with different adsorbents. The structures of obtained pure compounds were elucidated with different spectroscopic techniques, and two pure materials were tested for protection of DNA from damage, antioxidant, antitumor, and cytotoxicity.

Results:

Four pure compounds were obtained, of which fucosterol (1) and fucoxanthin (4) were tested; it was found that fucoxanthin has strong antioxidant and cytotoxicity against breast cancer (MCF-7) with IC₅₀ = 11.5 μg/ml.

Conclusion:

The naturally highly conjugated safe compound fucoxanthin could be used as antioxidant and as an antitumor compound.

Synthesis under microwave irradiation of [1,2,4]triazolo[3,4-b] [1,3,4]thiadiazoles and other diazoles bearing indole moieties and their antimicrobial evaluation

Microwave-assisted synthesis of some novel compounds, namely, 3-(2-methyl-1H-indol-3-yl)-6-aryl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles 5a,b was accomplished via bromination of 2-methyl-3-[4-(arylideneamino)-5-mercapto-4H-[1,2,4]triazol-3-yl]-1H-indoles 3a,b. Also, new [1,3,4]thiadiazoles 12a,b, [1,2,4]triazoles 15a,b and [1,3,4]oxadiazoles 19a,b, with indole moieties, were prepared by cyclization of 1-[(2-methyl-1H-indole)-3-carbonyl]thiosemicarbazides 8a,b under microwave irradiation using different reaction conditions. Moreover, reaction of acid hydrazide 7 with ethyl 2-(N-phenylhydrazono)-3-oxobutanoate (20) gave the respective phenylhydrazonopyrazole derivative 21 under the reaction conditions employed. The structures of the synthesized compounds were assigned based on elemental analyses and spectral data (IR, (1)H-NMR, (13)C-NMR, MS). The antifungal and antibacterial activities of the new products were also evaluated.

Cytotoxic and protective DNA damage of three new diterpenoids from the brown alga Dictoyota dichotoma

Three new diterpenes Amijiol acetate (3), dolabellane, Dolabellatrienol (4), and dolastane, Amijiol-7, 10-diacetate (9) were isolated together with the previously described Pachydictyol A (1), Isopachydictyol A (2), 8β-hydroxypachydictyol A (5), Amijiol (6), Isodictyohemiacetal (7) and Dictyol C (8) from the Red Sea brown alga Dictyota dichotoma var. implexa. The structures and relative stereochemistry of the new diterpenoids were proposed on the basis of their spectral data. Compounds 3 and 9 have potent activity against DNA damage, cytotoxicity against WI-38, HepG2, and MCF-7 cell lines, and antioxidant using ABTS and erythrocytes hemolysis.