Synthesis and in vitro antitumoral activity of new 3,5-dicyanopyridine derivatives

A new series of 2-amino-4-aryl-6-dialkylamino-3,5-dicyanopyridines, 20-47, were synthesized in satisfactory overall yield, through a simple synthetic strategy using 3-amino-3-(dialkylamino)-propenenitriles 1 and 2 as key intermediates. 3,5-Dicyanopyridine derivatives 20-47 were evaluated for their in vitro anticancer activity toward cell lines of nine different types of human cancers. Some of the newly prepared compounds demonstrated inhibitory effects on the growth of a wide range of cancer cell lines generally at 10(-6) M level and in some cases at 10(-8) M concentration.     

Synthesis and in vitro antitumoral activity of new hydrazinopyrimidine-5-carbonitrile derivatives

A new series of 2-amino-6-(2-alkyl or arylidenehydrazinyl)-4-(dialkylamino)pyrimidine-5-carbonitriles, 5-24, were synthesized in satisfactory overall yield, using 2-amino-4-(dialkylamino)-6-hydrazino-5-pyrimidinecarbonitriles 3, 4, as key intermediates, by applying classical synthetic methods to construct the hydrazone moiety at C-6 of the pyrimidine ring. Hydrazinopyrimidine derivatives 5-24 were evaluated for their in vitro anticancer activity toward cell lines of nine different types of human cancers. Some of the newly prepared compounds demonstrated inhibitory effects on the growth of a wide range of cancer cell lines generally at 10(-5)M level and in some cases at 10(-7)M concentrations.     

Synthesis and in vitro antitumor activity of new butenolide-containing dithiocarbamates

Three series of butenolide-containing dithiocarbamates were designed and synthesized. Their anti-tumor activity in vitro was evaluated. Among them compound I-14 exhibited broad spectrum anti-cancer activity against five human cancer cell lines with IC₅₀ <30 μM. Structure-activity relationship analysis showed that the introduction of dithiocarbamate side chains on the C-3 position of butenolide was crucial for anti-tumor activity.     

Synthesis and in vitro antitumor activity of new 4,5-dihydropyrazole derivatives

A series of 3,5-diaryl-4,5-dihydropyrazole regioisomers, and their 1-acetylated derivatives, bearing a 3,4,5-trimethoxyphenyl moiety combined with a variety of substituted phenyl rings, was synthesized and evaluated for antitumor activity. Results of the in vitro assay against a non-small cell lung carcinoma cell line (NCI-H460) showed several compounds to be endowed with cytotoxicity in micromolar to sub-micromolar range, depending on substitution pattern and position of aryl rings on 4,5-dihydropyrazole core. Potent and selective activity was also observed in the NCI 60 human cancer cell line panel. 5-(3,4,5-Trimethoxyphenyl)pyrazolines 31 and 39 were found to possess potent antiproliferative activity against SR and MDA-MB-435, with GI₅₀ inhibitory values in nanomolar range. Structure–activity relationships revealed that introduction of a (hydroxy)acetyl group at N-1 of inactive 5-(3,4,5-trimethoxyphenyl)pyrazolines, results in a clear in vitro activating effect. Compound 31 (IC₅₀ = 5.16 μM) showed inhibition of tubulin polymerization comparable to that of CA-4 (IC₅₀ = 4.92 μM).     

Synthesis and in vitro biological activity of new 4,6-disubstituted 3(2H)-pyridazinone-acetohydrazide derivatives

New 3(2H)-pyridazinone derivatives containing a N'-benzyliden-acetohydrazide moiety at position 2 were synthesized. The structures of these newly synthesized compounds were confirmed by IR, 1H NMR, and MS data. These compounds were tested for their antibacterial, antifungal, antimycobacterial, and cytotoxic activities. The compounds 2-[4-(4-chlorophenyl)-6-(morpholin-4-yl)-3-oxo-(2H)-pyridazin-2-yl]-N'-(4-tert-butylbenzyliden)acetohydrazide and 2-[4-(4-chlorophenyl)-6-(morpholin-4-yl)-3-oxo-(2H)-pyridazin-2-yl]-N'-(4-chlorobenzyliden) acetohydrazide exhibited activity against both Gram-positive and Gram-negative bacteria. Most of the compounds were active against E. coli ATCC 35218. The preliminary results of this study revealed that some target compounds exhibited promising antimicrobial activities.     

Synthesis and evaluation of antitumoral activity of ester and amide derivatives of 2-arylamino-6-trifluoromethyl-3-pyridinecarboxylic acids

The synthesis and antitumoral activity of ester and amide derivatives of 2-arylamino-6-trifluoromethyl-3-pyridinecarboxylic acids 8-58 is described. Trifluoromethylpyridine derivatives 8-58 were evaluated for their anticancer activity toward human tumoral cell lines by the National Cancer Institute (NCI). Most of them possess encouraging anticancer activity, having GI(50) values in the low micromolar to nanomolar concentration range. The 3,4,5-trimethoxyphenylamide 44 was the most active, and it is now under review by NCI Biological Evaluation Committee for possible further studies.     

Synthesis and in vitro activity of new methylenepiperidinyl and methylenepyrrolidinyl oxazolidinone antibacterial agents

We have prepared and evaluated the antibacterial activities of a series of substituted methylenepiperidinyl and methylenepyrrolidinyl oxazolidinones against several gram-positive strains including the resistant strains of Staphyloccus and Enterococcus, such as MRSA, CRSA, MSSA and VRE. Some of them showed comparable or superior in vitro activities (MIC) to vancomycin.     

Synthesis and in vitro antioxidant activity study of some new piperazinyl flavone compounds

Flavones exhibit a variety of beneficial effects and are well known for their medicinal importance in several diseases, including cardiovascular, neurodegenerative and cancer. The inclusion of the piperazine ring to the flavone backbone is an important strategy in drug discovery but only a few studies have synthesized piperazinyl flavone compounds to test their biological activity. While there is a major focus on the antioxidant properties of drugs in therapy of several diseases of inflammatory origin, we synthesized a series of the novel piperazinyl flavone analogues bearing the phenyl ring with different substituents. The analogues were evaluated for in vitro antioxidant activity against superoxide anion radical, hydroxyl radical, 2,2‐diphenyl‐1‐picrylhydrazyl radical, and hydrogen peroxide scavenging properties. The total antioxidant status based on the absorbance of the 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid) radical cation (ABTS^+?) and total antioxidant capacity using the Fe(III)‐ferrozine complex were also monitored. The results of the above studies showed that the compounds synthesized were found possessed moderate radical scavenging potential, and that their interaction with reactive oxygen species is complex and depends on their structural conformation and the type of substituent R in the piperazine ring being attached. Best antiradical activity were found for the compounds with methoxy groups on the phenyl ring of substituent R, whereas the presence of methoxy or trifluoromethyl groups in substituent R resulted in higher ABTS^+? and ion Fe(III) reduction. These compounds are promising molecules to be used for their antioxidant properties and may be regarded, after improvement of the antioxidant potential, to control diseases of free radical etiology.     

Synthesis of new isoxazoles and dihydroisoxazoles and in vitro evaluation of their antifungal activity

New 2-(2,4-dihalogenophenyl)-1-(1H-imidazol-1-yl)-3-(isoxazol-5-yl)propan-2-ols and 2-(2,4-dihalogenophenyl)-1-(1H-imidazol-1-yl)-3-(4,5-dihydroisoxazol-5-yl)propan-2-ols were synthesized by 1,3-dipolar cycloaddition between homopropargylic or homoallylic alcohols and in-situ generated nitrile oxide. Their antifungal activity was evaluated against Candida albicans, C. glabrata, Aspergillus fumigatus and an azole-resistant petite mutant of C. glabrata. Preliminary SAR results are discussed.     

Synthesis and in vitro antifungal activities of new 3-substituted benzopyrone derivatives

A series of new benzopyrone compounds were designed and synthesized and their antifungal activities in vitro were evaluated. The results showed that the benzopyrone derivatives with short terminal alkyl chain exhibited potent antifungal activity, which represent a novel class of promising leads for the development of novel non-azole antifungal agents. Compound 5j is the most potent one with MIC(80) value 1.5 μg/mL against Trichophyton rubrum. Flexible molecular docking was used to analyze the structure-activity relationships (SARs) of the compounds. The designed compounds interact with CA-CYP51 through hydrophobic and van der Waals interactions.     

Synthesis and in vitro antiproliferative and antibacterial activity of new thiazolidine-2,4-dione derivatives

In our present research, we synthesised new thiazolidine-2,4-diones (12–28). All the newly synthesised compounds were evaluated for antiproliferative and antibacterial activity. Antiproliferative evaluation was carried out using normal human skin fibroblasts and tumour cell lines: A549, HepG2, and MCF-7. The IC₅₀ values were determined for tested compounds revealing antiproliferative activity. Moreover, safety index (SI) was calculated. Among all tested derivatives, the compound 18 revealed the highest antiproliferative activity against human lung, breast, and liver cancer cells. More importantly, the derivative 18 showed meaningfully lower IC₅₀ values when compared to the reference substance, irinotecan, and relatively high SI values. Moreover, newly synthesised compounds were screened for the bacteria growth inhibition in vitro. According to our screening results, most active compound was the derivative 18 against Gram-positive bacteria. Therefore, it may be implied that the novel compound 18 appears to be a very promising agent for anticancer treatment.     

Synthesis and in vitro antimicrobial activity of new 4-phenyl-5-methyl-4H-1,2,4-triazole-3-thione derivatives

This study presents the synthesis, spectral analysis and antimicrobial evaluation of a new series of substituted 1,2,4-triazole (5a–i) and 1,3,4-thiadiazole derivatives (9a, c, g, h). New compounds were obtained by cyclization reaction of acyl thiosemicarbazide derivatives in the presence of alkaline and acidic media. All synthesized compounds were screened for their in vitro antimicrobial activities. Nine of the compounds had potential activity against Gram-positive bacteria (MIC?=?3.91–500 µg/mL). Some compounds showed good activity especially against: Micrococcus luteus ATCC 10240 (MIC?=?3.91?31.25 µg/mL), Bacillus subtilis ATCC 6633 (MIC?=?15.63? 62.5 µg/mL), and Staphylococcus aureus ATCC 25923 (MIC?=?15.63?125 µg/mL).     

Synthesis and in vitro activity of new oxazolidinone antibacterial agents having substituted isoxazoles.

Two series of oxazolidinone derivatives having substituted isoxazoles were synthesized and tested for antibacterial activities against several Gram-positive strains including the resistant strains of Staphylococcus and Enterococcus, such as MRSA, CRSA, MSSA and VRE. Some of them showed in vitro activities (MIC) comparable or superior to the reference compound vancomycin.     

Synthesis of new oxathiazinane dioxides and their in vitro cancer cell growth inhibitory activity

New oxathiazinane dioxides have been derived from d- and l-serine and tested for their in vitro cell growth inhibitory activity toward SKBR3 breast cancer cells. (5R)-5-(4-(4′-Bromomethyl)phenyl)benzyloxymethyl-[1,3,4]-oxathiazinane-3,3-dioxide showed a cytotoxicity of IC₅₀ ≈ 10 μM.     

New liposome-encapsulated-polyoxometalates: synthesis and antitumoral activity

Liposome-encapsulated polyoxometalates (abbreviated as LEP): incorporating K(6)SiW(11)TiO(40) {(SiW(11)Ti) LEP} have been synthesized and structurally characterized by elemental analysis, and IR, UV-Vis, and NMR spectroscopy. The particle sizes of these complexes ranged from 15 to 60 nm. The polyoxometalate retained the parent structure after encapsulation by the liposome. Based upon in vitro measurements with KB and HeLa cancer cells, the liposome-encapsulation enhances cell-membrane penetration, and the stability and antitumoral activity of the polyoxometalate. The toxicity of the polyoxometalate was reduced when LEPs were employed against HL-60 tumors in vivo.     

Synthesis,in vitro antiproliferative activity and kinase profile of new benzimidazole and benzotriazole derivatives

Protein kinase 2 (CK2), a member of the serine/threonine kinase family, has been established as a promising target in anticancer therapy. New derivatives of known CK2 inhibitors 4,5,6,7-tetrabromo-1H-benzimidazole (TBBi) and 4,5,6,7-tetrabromo-1H-benzotriazole (TBBt) bearing azide or substituted triazole groups were synthesized. Their influence on the activity of human recombinant CK2α and cytotoxicity against normal and cancer cell lines were evaluated. TBBi derivatives with triazole substituted with carboxyl substituent (7 and 10) exhibited the most potent inhibitory activity against CK2 with K_i value in the range of 1.96–0.91 μM, respectively. New TBBi derivatives 2, 3, 5 and 9 have demonstrated the EC₅₀, in the range of 12–25 μM and 13–29 μM respectively towards CCRF-CEM and MCF-7 cells. Derivatives TBBi decreased viability of cancer cells more efficiently than BALB cells and the biggest differences were observed for the azide substituted compounds 3 and 5. The effect of the most active compounds on the activity of eight off-target kinases was evaluated. Inhibitory efficiency of CK2-mediated p65 phosphorylation was demonstrated for the TBBi and compound 12.     

Synthesis and antituberculosis activity of new 3-alkylsulfanyl-1,2,4-triazole derivatives

The increasing clinical importance of drug-resistant mycobacterial pathogens has lent additional urgency to microbiological research and new antimycobacterial compound development. For this purpose, new alkylsulfanyltriazoles were synthesized and evaluated for antituberculosis activity. The reaction of thienyl-2-acetic acid with thiocarbohydrazide gave the mercaptotriazoles (II). The 4-amino-5-(2-thienylmethyl)-3-[1-(2-thienyl)-3-aryl)propion-3-yl]sulfanyl-4H-1,2,4-triazole (III) derivatives were synthesized by reacting the mercaptotriazoles with chalcones (I). Antituberculosis activities of the synthesized compounds were determined by broth microdilution assay, the Microplate Alamar Blue Assay, in BACTEC12B medium and results were screened in-vitro, using BACTEC 460 Radiometric System against Mycobacterium tuberculosis H₃₇Rv (ATCC 27294) at 6.25?μg/ml and the tested compounds showed considerable inhibition ranging from 58–84%.     

Synthesis and antituberculosis activity of new 3-alkylsulfanyl-1,2,4-triazole derivatives

The increasing clinical importance of drug-resistant mycobacterial pathogens has lent additional urgency to microbiological research and new antimycobacterial compound development. For this purpose, new alkylsulfanyltriazoles were synthesized and evaluated for antituberculosis activity. The reaction of thienyl-2-acetic acid with thiocarbohydrazide gave the mercaptotriazoles (II). The 4-amino-5-(2-thienylmethyl)-3-[1-(2-thienyl)-3-aryl) propion-3-yl] sulfanyl-4H-1,2,4-triazole (III) derivatives were synthesized by reacting the mercaptotriazoles with chalcones (I). Antituberculosis activities of the synthesized compounds were determined by broth microdilution assay, the Microplate Alamar Blue Assay, in BACTEC 12B medium and results were screened in-vitro, using BACTEC 460 Radiometric System against Mycobacterium tuberculosis H37Rv (ATCC 27294) at 6.25 microg/ml and the tested compounds showed considerable inhibition ranging from 58-84%.     

Synthesis and antirhinovirus activity of new 3-benzyl chromene and chroman derivatives

A series of 3-benzyl chromenes and chromans were synthesized and tested in vitro against human rhinovirus (HRV) 1B and 14, two representative serotypes for rhinovirus group B and A, respectively. All the new compounds, with the exception of 3-benzyl-2H-chromene (3a), showed a potent activity against HRV serotype 1B within micro or submicromolar range (IC₅₀s from 0.11 to 6.62 μM). The low cytotoxicity of all the derivatives resulted in compounds with high therapeutic index (TI). On the contrary, HRV 14 infection was only weakly inhibited by the majority of these compounds. The 3-benzylidenechromans 2b and 2c showed the highest anti-HRV 1B activity (IC₅₀ 0.12 and 0.11 μM, respectively) coupled with remarkable TI (625.00 and 340.91, respectively). Mechanism of action studies on (Z)-3-(4-chlorobenzylidene)chroman (2b) suggest that the new compounds behave as capsid binders and interfere with very early stages of HRV 1B replication, similarly to related flavanoids.