Roman Lesyk

Synthesis of novel thiazolone-based compounds containing pyrazoline moiety and evaluation of their anticancer activity

To examine the anticancer activity several novel thiazolone-based compounds containing 5-aryl-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl framework were obtained. Reaction of 5-aryl-3-phenyl-4,5-dihydropyrazole with 4-thioxo-2-thiazolidinone or 2-carbethoxymethylthio-2-thiazoline-4-one yielded starting 4- (1 and 2) or 2-substituted (11 and 12) thiazolones which were utilized in Knoevenagel condensation for obtaining a series of 5-arylidene derivatives 3-10, 13-18. Alternatively 11, 12 and their 5-arylidene derivatives were synthesized by means of 3-phenyl-5-aryl-1-thiocarbamoyl-2-pyrazoline as S,N-binucleophile via [2+3]-cyclocondensation approach. The structures of compounds were determined by (1)H, (13)C NMR, LC-MS, EI-MS and X-ray analysis. The in vitro anticancer activity of synthesized compounds were tested by the National Cancer Institute and most of them displayed anticancer activity on leukemia, melanoma, lung, colon, CNS, ovarian, renal, prostate and breast cancer cell lines. Relations between structure and activity are discussed, the most efficient anticancer compound 16 was found to be active with selective influence on colon cancer cell lines, especially on HT 29 (logGI(50)=-6.37).

Synthesis and anticancer activity evaluation of 4-thiazolidinones containing benzothiazole moiety

Antitumor screening of several novel 4-thiazolidinones with benzothiazole moiety has been performed. Reactions of (benzothiazole-2-yl)hydrazine with trithiocarbonyl diglycolic acid or 6-methyl-2-aminobenzothiazole with 2-carbethoxymethylthio-2-thiazoline-4-one have yielded starting 3- (1) or 2-substituted (11) 4-thiazolidinones which have been subsequently utilized in a Knoevenagel condensation for obtaining a series of 5-arylidene derivatives 2-10, 12-16. Compound 11 has been obtained alternatively by a counter synthesis method based on the reaction of 2-chloro-N-(6-methylbenzothiazol-2-yl)-acetamide and ammonium thiocyanate. The structures of compounds have been determined by (1)H, (13)C NMR, IR and X-ray analysis. In vitro anticancer activity of the synthesized compounds was tested by the National Cancer Institute and two (6, 16) of them has revealed the anticancer activity on leukemia, melanoma, lung, colon, CNS, ovarian, renal, prostate and breast cancers cell lines. Among tested compounds, 2-{2-[3-(benzothiazol-2-ylamino)-4-oxo-2-thioxothiazolidin-5-ylidenemethyl]-4-chlorophenoxy}-N-(4-methoxyphenyl)-acetamide (6) was found to be the most active candidate with average logGI(50) and logTGI values -5.38 and -4.45 respectively.

Synthesis of New 4-Thiazolidinone-, Pyrazoline-, and Isatin-Based Conjugates with Promising Antitumor Activity

The synthesis and antitumor activity screening of novel 3-[2-(3,5-diaryl-4,5-dihydropyrazol-1-yl)-4-oxo-4,5-dihydro-1,3-thiazol-5-ylidene]-2,3-dihydro-1H-indol-2-ones 1-23 and 3-(3,5-diarylpyrazol-1-yl)-2,3-dihydro-1H-indol-2-ones 24-39 are performed. In vitro anticancer activity of the synthesized compounds was tested by the National Cancer Institute. Most of them displayed anticancer activity on leukemia, melanoma, lung, colon, CNS, ovarian, renal, prostate, and breast cancers cell lines. The structure-activity relationship is discussed. The most effective anticancer compound 10 was found to be active with mean GI₅₀ and TGI values of 0.071 μM and 0.76 μM, respectively. It demonstrated the highest antiproliferative influence on the non-small-cell lung cancer cell line HOP-92 (GI₅₀ < 0.01 μM), colon cancer line HCT-116 (GI₅₀ = 0.018 μM), CNS cancer cell line SNB-75 (GI₅₀ = 0.0159 μM), ovarian cancer cell line NCI/ADR-RES (GI₅₀ = 0.0169 μM), and renal cancer cell line RXF 393 (GI₅₀ = 0.0197 μM).

Manganic encephalopathy due to "ephedrone" abuse.

We describe the clinical and neuroimaging features of 6 drug‐abuse patients with self‐inflicted manganese poisoning. The patients injected a home‐brewed mixture called “ephedrone” (slang term) that contained manganese to produce an amphetamine‐like euphoria. The desired chemical product, phenylpropanoneamine (also called methcathinone), was synthesized from a common‐cold–remedy compound using permanganate as the catalyst. Manganese was a by‐product in the ephedrone mixture. After months of self‐injections, a clinical picture emerged, consisting of apathy, bradykinesia, gait disorder with postural instability, and spastic‐hypokinetic dysarthria. There was no response to levodopa. The MRI revealed symmetric hyperintense T1‐weighted signals in the basal ganglia, typical of manganese accumulation.

Synthesis of 5-arylidene-2-amino-4-azolones and evaluation of their anticancer activity

Series of novel 5-arylidene-2-arylaminothiazol-4(5H)-ones and 2-aryl(benzyl)amino-1H-imidazol-4(5H)-ones were synthesized from appropriate 2-alkylthioazol-4-ones using nucleophilic substitution in position 2 by various anilines and benzylamines and Knoevenagel reaction. X-ray structural studies of 22 revealed the structure to be intermediate between amino and imino tautomeric forms. All the target compounds were evaluated for the anticancer activity in vitro in standard National Cancer Institute 60 cancer cell lines assay. Majority of compounds showed significant antitumor cytotoxicity effect at micromolar and submicromolar level (Mean LogGI50 ranges -5.77 to -4.35). Some of the most potent compounds, namely 10 and 13, possessed selectively high effect on all leukemia cell lines at submicromolar level (Mean LogGI50 [leukemia lines], respectively, -6.41 and -6.29), which are probably associated with immunosuppressive activity. Individual cancer cell lines sensitivity to synthesized compounds and SAR studies are discussed. COMPARE analysis allowed to disclose probable modes of anticancer action for synthesized compounds, in particular showed number of high correlations with activity patterns of alkylating agents (PCC approximately 0.606-0.731).

Synthesis and in vitro anticancer activity of 2,4-azolidinedione-acetic acids derivatives.

The synthesis and evaluation of anticancer activity of 2,4-thia(imida)zolidinedione-3- and 5-acetic acids amides were described. The structures of compounds were determined by IR, (1)H NMR, and MS analysis. In vitro anticancer activity of these compounds has been tested in National Cancer Institute (NCI) and the relationships between structure and anticancer activity are discussed. Among 2,4-azolidinedione-acetic acids derivatives 2-[5-(4-chlorobenzylidene)-2,4-dioxo-imidazolidin-3-yl]-N-(2-trifluoromethyl-phenyl)-acetamide (Ic) was superior to other related compounds in terms of high selectivity for the leukemia CCRF-CEM (logGI(50)=-6.06), HL-60(TB) (logGI(50)=-6.53), MOLT-4 (logGI(50)=-6.52) and SR (logGI(50)=-6.51) cell lines.

Synthesis and Anticancer Activity of Isatin-Based Pyrazolines and Thiazolidines Conjugates

The synthesis and antitumor activity screening of novel isatin based conjugates with thiazolidine and pyrazoline moieties were performed. Reaction of 3,5‐diaryl‐4,5‐dihydropyrazoles with chloroacetyl chloride yielded starting 2‐chloro‐1‐(3,5‐diaryl‐4,5‐dihydropyrazol‐1‐yl)‐ethanones which were utilized in alkylation of isatin and 5‐bromoisatin. Thus, corresponding 1‐[2‐(3,5‐diaryl‐4,5‐dihydropyrazol‐1‐yl)‐2‐oxoethyl]‐1H‐indole‐2,3‐diones (1a–1d) have been obtained. The compounds 1a–1d have been used in Knoevenagel condensation with 4‐thiazolidinones for obtaining a series of 5‐ylidenederivatives 2a–2f and 3a–3d. The synthesized compounds were tested for their anticancer activity in NCI60 cell lines. Among the tested compounds, 5‐bromo‐1‐{2‐[5‐(4‐chlorophenyl)‐3‐(4‐methoxyphenyl)‐4,5‐dihydropyrazol‐1‐yl]‐2‐oxoethyl}‐1H‐indole‐2,3‐dione (1d) was found to be the most active candidate with selective influence on leukemia subpanel tumor cell lines with GI50 values range of 0.69–3.35 µM.

A Facile Synthesis and Anticancer Activity Evaluation of Spiro(Thiazolidinone-Isatin) Conjugates

The synthesis and evaluation of the anticancer activity of 3′-aryl-5′-arylidene-spiro[3H-indole-3,2′-thiazolidine]-2,4′(1H)-diones and spiro[3H-indole-3,2′-thi-azolidine]-2,4′(1H)-dione-3′-alkanoic acid esters were described. The structure of the compounds was determined by 1H and 13C NMR and their in vitro anticancer activity was tested in the National Cancer Institute. Among the tested compounds, (5′Z)-5′-(benzylidene)-3′-(4-chlorophenyl)spiro[3H-indole-3,2′-thia-zolidine]-2,4′(1H)-dione (IIa) and (5′Z)-3′-(4-chlorophenyl)-5′-[4-(1-methylethyl)-benzylidene]spiro[3H-indole-3,2′-thiazolidine]-2,4′(1H)-dione (IIb) were superior to other related compounds.

Synthesis and Anticancer Activity of Novel Nonfused Bicyclic Thiazolidinone Derivatives

A series of new 2-{4-oxo-2-[(4-oxothiazolidin-2-ylidene)-hydrazono]-thiazolidin-5-yl}-N-arylacetamides ( 4a–e ), 5-(2-oxo-2-aryl-ethyl)-2-[(4-oxothiazolidin-2-ylidene)-hydrazono]-thiazolidine-4-ones ( 5a–d ), 2-(4-oxo-2-[(2-oxothiazolidin-4-ylidene)-hydrazono]-thiazolidin-5-yl)-N-arylacetamides ( 7a–e ), and 5-(2-oxo-2-aryl-ethyl)-2-[(2-oxothiazolidin-4-ylidene)-hydrazono]-thiazolidine-4-ones ( 8a–d ) have been synthesized starting from 2-thioxothiazolidin-4-one and 4-thioxothiazolidin-2-one through a multistep reaction sequence. 2-Thioxothiazolidin-4-one was alkylated via the intermediate formation of the triethylammonium salt 1 by ethyl chloroacetate. Compound 2 and 4-thioxothiazolidin-2-one reacted with thiosemicarbazides to give the 1-(4-thiazolidinone-2-ylidene)-4-R-thiosemicarbazones ( 3a,b ) and 1-(2-thiazolidinone-4-ylidene)thiosemicarbazones ( 6a,b ), respectively. Following [2+3]-cyclization of thiazolidinone-substituted thiosemicarbazones ( 3a,b and 6a,b) with N-arylmaleimides and aroylacrylic acids as equivalents of dielectrophilic synthon [C2]2 +, novel non-fused bicyclic thiazolidinones ( 4a–e, 5a–d, 7a–e, 8a–d ) were synthesized. The structures of the new compounds ( 4a–e, 5a–d, 7a–e, 8a–d ) were established on the basis of their elemental analysis and 1H NMR and mass spectral data. Eight of the synthesized compounds were tested, and three of them displayed different levels of antitumor activity. The most efficient antitumor agent—2-{4-oxo-3-furylmethyl-2-[(4-oxothiazolidin-2-ylidene)-hydrazono]-thiazolidin-5-yl}-N-4-chlorophenylacetamide ( 4d ) was found to be active against leukemia, melanoma, lung, colon, CNS, ovarian, renal, prostate, and breast cancer cell lines with mean lgGI50 and lgTGI values of –5.35 and –4.78, respectively.

Synthesis and antitrypanosomal activity of new 6,6,7-trisubstituted thiopyrano[2,3-d][1,3]thiazoles

А series of novel 6,6,7-trisubstituted thiopyrano[2,3-d][1,3]thiazoles-based molecules have been synthesized and evaluated as potential antitrypanosomal agents. The most active analogue 3b inhibited Trypanosoma brucei brucei and Trypanosoma brucei gambiense with an IC(50) of 0.26 and 0.42 μМ, respectively. They could be considered as potent hits for further antitrypanosomal drug discovery efforts.