Kaan Kucukoglu

Synthesis of 4-(2-substituted hydrazinyl)benzenesulfonamides and their carbonic anhydrase inhibitory effects

Abstract In this study, 4-(2-substituted hydrazinyl)benzenesulfonamides were synthesized by microwave irradiation and their chemical structures were confirmed by 1H NMR, 13CNMR, and HRMS. Ketones used were: Acetophenone (S1), 4-methylacetophenone (S2), 4-chloroacetophenone (S3), 4-fluoroacetophenone (S4), 4-bromoacetophenone (S5), 4-methoxyacetophenone (S6), 4-nitroacetophenone (S7), 2-acetylthiophene (S8), 2-acetylfuran (S9), 1-indanone (S10), 2-indanone (S11). The compounds S9, S10 and S11 were reported for the first time, while S1–S8 was synthesized by different method than literature reported using microwave irradiation method instead of conventional heating in this study. The inhibitory effects of 4-(2-substituted hydrazinyl)benzenesulfonamide derivatives (S1–S11) against hCA I and II were studied. Cytosolic hCA I and II isoenzymes were potently inhibited by new synthesized sulphonamide derivatives with Kis in the range of 1.79 ± 0.22–2.73 ± 0.08 nM against hCA I and in the range of 1.72 ± 0.58–11.64 ± 5.21 nM against hCA II, respectively.

Synthesis, cytotoxicity and carbonic anhydrase inhibitory activities of new pyrazolines

Abstract A series of polymethoxylated-pyrazoline benzene sulfonamides were synthesized, investigated for their cytotoxic activities on tumor and non-tumor cell lines and inhibitory effects on carbonic anhydrase isoenzymes (hCA I and hCA II). Although tumor selectivity (TS) of the compounds were less than the reference compounds 5-Fluorouracil and Melphalan, trimethoxy derivatives 4, 5, and 6 were more selective than dimethoxy derivatives 2 and 3 as judged by the cytotoxicity assay with the cells both types originated from the gingival tissue. The compound 6 (4-[3-(4-methoxyphenyl)-5-(3,4,5-trimethoxyphenyl)-4,5-dihydro-1H-pyrazol-1-yl] benzene sulfonamide) showed the highest TS values and can be considered as a lead molecule of the series for further investigations. All compounds synthesized showed superior CA inhibitory activity than the reference compound acetazolamide on hCA I, and II isoenzymes, with inhibition constants in the range of 26.5–55.5 nM against hCA I and of 18.9–28.8 nM against hCA II, respectively.

Microwave-assisted synthesis and bioevaluation of new sulfonamides

Abstract In this study, 4-[5-(4-hydroxyphenyl)-3-aryl-4,5-dihydro-1H-pyrazol-1-yl]benzenesulfonamide derivatives (8-14) were synthesized for the first time by microwave irradiation and their chemical structures were confirmed by 1H NMR, 13C NMR and HRMS. Cytotoxic activities and inhibitory effects on carbonic anhydrase I and II isoenzymes of the compounds were investigated. The compounds 9 (PSE = 4.2), 12 (PSE = 4.1) and 13 (PSE = 3.9) with the highest potency selectivity expression (PSE) values in cytotoxicity experiments and the compounds 13 (Ki = 3.73 ± 0.91 nM toward hCA I) and 14 (Ki = 3.85 ± 0.57 nM toward hCA II) with the lowest Ki values in CA inhibition studies can be considered as leader compounds for further studies.

Synthesis of some Mannich bases with dimethylamine and their hydrazones and evaluation of their cytotoxicity against Jurkat cells.

1-Aryl-3-dimethylamino-1-propanone hydrochlorides type mono Mannich bases, D series, and corresponding hydrazone derivatives, K series, were synthesized and their cytotoxicity was tested against Jurkat cells (transformed human T-lymphocytes). The aryl part was changed as phenyl in D1 and K1, 4-methylphenyl in D2 and K2, 4-methoxyphenyl in D3 and K3, 4-hydroxyphenyl in D4 and K4, 4-chlorophenyl in D5 and K5, 3-methoxyphenyl in D6 and K6, 4-fluorophenyl in D7 and K7, 4-bromophenyl in D8 and K8, 3-hydroxyphenyl in D9 and K9, and 2-acetylthiophene in D10 and K10. Of the compounds synthesized, K2, K3, K5, K6, K7, K8, K9, and K10 are reported for the first time. Cytotoxic activities of the D and K series were compared with each other to see alterations in bioactivity depending on the chemical structures in Jurkat cells. Cytotoxicities of the compounds synthesized were also compared with the reference compound, 5-fluorouracil (CAS 148-82-3). Mono Mannich bases, D1 (3.60 times), D2 (4.45 times), D3 (2.46 times), D4 (3.52 times), D5 (5.18 times), D6 (3.20 times), D7 (3.23 times), D8 (3.95 times), D9 (3.36 times) and D10 (3.99 times) had 2.46-5.18 times higher cytotoxic potency than the reference compound 5-fluorouracil against Jurkat cells, while hydrazones K1 (4.92 times), K2 (4.65 times), K3 (6.04 times), K4 (6.34 times), K5 (4.67 times), K6 (5.12 times), K7 (5.39 times), K8 (8.31 times), K9 (4.65 times) and K10 (8.65 times) had 4.65-8.65 times higher cytotoxic potency than the reference compound 5-fluorouracil against the same cell line. On the other hand, hydrazone compounds K1 (1.37 times), K3 (2.46 times), K4 (1.80 times), K6 (1.60 times), K7 (1.67 times), K8 (2.11 times), K9 (1.38 times), and K10 (2.17 times) had 1.37-2.46 times higher cytotoxic potency than their corresponding mono Mannich bases. The results of this study suggest that hydrazones were better compounds compared with the corresponding mono Mannich bases in terms of cytotoxicity, and they may serve as model compounds to develop new cytotoxic agents for further studies.

Synthesis of new N,N′-bis[1-aryl-3-(piperidine-1-yl)propylidene]hydrazine dihydrochlorides and evaluation of their cytotoxicity against human hepatoma and breast cancer cells

Abstract N,N′-Bis[1-aryl-3-(piperidine-1-yl)propylidene]hydrazine dihydrochlorides were synthesized by the reaction of 2 mols of 1-aryl-3-(piperidine-1-yl)-1-propanone hydrochlorides with 1 mol of hydrazine hydrate. Aryl part was C6H5 (P1), 4-CH3C6H4 (P2), 4-CH3OC6H4 (P3), 4-HOC6H4 (P4), 4-ClC6H4 (P5), 3-CH3OC6H4 (P6), 4-FC6H4 (P7) and 4-BrC6H4 (P8). Except P1, all compounds were reported for the first time. The chemical structures were confirmed by UV, 1H NMR, 13C NMR and HRMS spectra. P1, P2, P7 and P8 against human hepatoma (Huh7) cells and P1, P2, P4, P5, P6, P7 and P8 against breast cancer (T47D) cells have shown cytotoxicity. P1, P2 and P7 had more potent cytotoxicity against Huh7 cells than the reference compound 5-FU, whereas only P2 was more potent than the 5-FU against T47D cells. Representative compound P7 inhibited the mitochondrial respiration at 144, 264 and 424 µM concentrations dose-dependantly in liver homogenates. The results suggest that P1, P2, P7 and P8 may serve as model compounds for further synthetic studies.

Synthesis and antimicrobial activity evaluation of new dithiocarbamate derivatives bearing thiazole/benzothiazole rings

GRAPHICAL ABSTRACT ABSTRACT The synthesis of 2-(substituted phenyl)-2-oxoethyl 4-(pyrimidin-2-yl)piperazin-1-carbodithiodate (A1-A24) derivatives and 2-(4-substituted thiazol-2-ylamino)-2-oxoethyl 4-(pyrimidin-2-yl)piperazin-1-carbodithiodate (B1-B14) derivatives was undertaken starting from the potassium salt of 4-(2-pyrimidinyl)piperazine dithiocarbamate. The structures of the obtained compounds were elucidated by 1H NMR, 13C NMR, MS spectral data, and elemental analysis. The antimicrobial activity of the thirty eight newly synthesized compounds were tested against 12 microorganism strains using the microdilution technique. Compounds 2-(4-ethoxycarbonylthiazol-2-ylamino)-2-oxoethyl 4-(pyrimidin-2-yl)piperazin-1-carbodithiodate (B12), 2-(3-fluorophenyl)-2-oxoethyl 4-(pyrimidin-2-yl)piperazin-1-carbodithiodate (A18) and 2-(3,4-difluorophenyl)-2-oxoethyl 4-(pyrimidin-2-yl)piperazin-1-carbodithiodate (A21) were determined to possess high antimicrobial activity.

Synthesis and evaluation of new thiadiazole derivatives as potential inhibitors of human carbonic anhydrase isozymes (hCA-I and hCA-II).

Abstract 2-[[5-(2,4-Difluoro/dichlorophenylamino)-1,3,4-thiadiazol-2-yl]thio] acetophenone derivatives (3a--s) were designed as human carbonic anhydrase isozymes (hCA-I and hCA-II) inhibitors and synthesized. hCA-I and hCA-II were purified from erythrocyte cells by the affinity chromatography. The inhibitory effects of 18 newly synthesized acetophenones on hydratase activity of these isoenzymes were studied in vitro. The average IC50 values of the new compounds for hydratase activity ranged from 0.033 to 0.14 μM for hCA-I and from 0.030 to 0.11 μM for hCA-II. Among the newly synthesized compounds, 2-[[5-(2,4-dichlorophenylamino)-1,3,4-thiadiazol-2-yl]thio]-4′-bromoacetophenone (3n) can be considered as a promising hCA-II inhibitor owing to its selective and potent inhibitory effect on hCA-II.

Synthesis of 3-aroyl-4-aryl-1-isopropylamino-4-piperidinols and evaluation of the cytotoxicities of the compounds against human hepatoma and breast cancer cell lines

Abstract Some 4-piperidinol derivatives were synthesized and their cytotoxicity was tested against human hepatoma (Huh7) and breast cancer (T47D) cells. Aryl part was changed as phenyl in 2a, 4-methylphenyl in 2b, 4-methoxyphenyl in 2c, 4-chlorophenyl in 2d, 4-fluorophenyl in 2e, 4-bromophenyl in 2f, 4-nitrophenyl in 2g and 2-thienyl in 3. Compounds were synthesized and reported for the first time by this study except 2a and 2d. Chemical structures were confirmed by 1H NMR, 13C NMR, IR, MS and elemental analyses. Compounds 2a (3.1 times), 2c (3.8 times), 2f (4.6 times), 2g (1.3 times) and 3 (3.2 times) had 1.3–4.6 times higher cytotoxic potency than the reference compound 5-FU against Huh7 cell line while all the compounds synthesized had shown lower activities against T47D cell line than 5-FU. In the light of these results, compounds 2a, 2c, 2f, 2g and 3 may serve as model compounds for further studies.

Cytotoxicities of novel hydrazone compounds with pyrrolidine moiety: inhibition of mitochondrial respiration may be a possible mechanism of action for the cytotoxicity of new hydrazones

N,N’-Bis[1-aryl-3-pyrrolidine-1-yl)propylidene]hydrazine dihydrochlorides (R1–R7) were synthesized by the reaction of 2 mols of 1-aryl-3-(pyrrolidine-1-yl)-1-propanone hydrochlorides with 1 mol of hydrazine hydrate and reported for the first time with their detailed spectral analysis and cytotoxicities towards human hepatoma (Huh7) and breast cancer (T47D) cell lines. Compounds R2, R6, and R7 with the IC50 values of 5.16, 6.96, and 5.96 μM, respectively, showed higher cytotoxic potency than the reference compound 5-FU with 7.0 μM against Huh7 cell line. However, all compounds did not show better cytotoxic activities than 5-FU against T47D cell line at the conditions studied. The representative compound of series, R2, inhibited the mitochondrial respiration at 90, 165, and 265 µM concentrations in a dose dependent manner in liver homogenates, suggesting that mitochondrial respiration may be one of the contributing factor to the cytotoxicity of the compounds synthesized. The compounds R2, R6, and R7 can be chosen as the leader compounds of this study for further studies.

In Silico Molecular Docking And Adme Studies Of 1,3,4-Thiadiazole Derivatives In Relation To In Vitro Pon1 Activity

BACKGROUND Paraoxonase 1 (PON1) is a paraoxonase, arylesterase and lactonase associated with protection of lipoproteins and cell membranes against oxidative modification. OBJECTIVE Based on antioxidative properties of PON1 and significance of 1,3,4-thiadiazoles in pharmaceutical chemistry, herein we aimed to evaluate the potentials of 1,3,4-thiadiazole derivatives as PON1 activators. METHODS 2-[[5-(2,4-Difluoro/dichlorophenylamino)-1,3,4-thiadiazol-2-yl]thio]acetophenone derivatives (1-18) were in vitro evaluated for their activator effects on PON1 which was purified using ammonium sulfate precipitation (60-80%) and DEAE-Sephadex anion exchange chromatography. Molecular docking studies were performed for the detection of affinities of all compounds to the active site of PON1. Moreover, Absorption, Distribution, Metabolism and Excretion (ADME) properties of all compounds were also in silico predicted. In silico molecular docking and ADME studies were carried out according to modules of Schrodingers Maestro molecular modeling package. RESULTS All compounds, particularly compounds 10, 13 and 17, were determined as promising PON1 activators and apart from compound 1, all of them were detected in the active site of PON1. Besides, ADME results indicated that all compounds were potential orally bioavailable drug-like molecules. CONCLUSION PON1 activators, compounds 10, 13 and 17 stand out as potential drug candidates for further antioxidant studies and these compounds can be investigated for their therapeutic effects in many disorders such as atherosclerosis, diabetes mellitus, obesity, chronic liver inflammation and many more.