Molecular Docking Studies of N-(((5-Aryl-1,3,4-oxadiazol-2-yl)amino)methyl)- and N-(2,2,2-Trichloro-1-((5-aryl-1,3,4-oxadiazol-2-yl)amino)ethyl)carboxamides as Potential Inhibitors of GSK-3β

 

Pavlo V. Zadorozhnii*, Ihor O. Pokotylo, Vadym V. Kiselev, Oxana V. Okhtina, Aleksandr V. Kharchenko

Department of Organic Substances and Pharmaceutical Preparations, Ukrainian State University of Chemical Technology, Gagarin Ave., 8, Dnipro 49005, Ukraine.

*Corresponding Author E-mail: torfp@i.ua

 

ABSTRACT:

In this study it has been carried out in silico modeling of glycogen synthase kinase-3β inhibition by N-amidoalkylated derivatives of 2-amino-1,3,4-oxadiazole, using software ArgusLab 4.0.1. It has been shown that the structures being studied mainly form stronger complexes with the enzyme compared to the known inhibitor. Based on the results of molecular docking, the compounds leaders N-(((5-(2-bromophenyl)-1,3,4-oxadiazol-2-yl)amino)methyl) benzamide and 2,4-dichloro-N-(2,2,2-trichloro-1-((5-(p-tolyl)-1,3,4-oxadiazol-2-yl)amino)ethyl) benzamide have been chosen. The compound N-(((5-(2-bromophenyl)-1,3,4-oxadiazol-2-yl)amino)methyl)benzamide has been known before, and the compound 2,4-dichloro-N-(2,2,2-trichloro-1-((5-(p-tolyl)-1,3,4-oxadiazol-2-yl)amino)ethyl) benzamide has been obtained for the first time. They can be recommended for further studies in the treatment of Alzheimer's disease.

 

KEYWORDS: Alzheimer’s Disease, 1,3,4-Oxadiazole, Docking, GSK-3β, Inhibitors, Synthesis, ArgusLab.

 

 


INTRODUCTION:

Alzheimer's Disease (AD) is a neurodegenerative disease characterized by pathological features of neurofibrillary tangles (tau pathology) and β-amyloid plaques in the cerebral cortex. In this case, pathology of β-amyloid plaques varies considerably, and neurofibrillary tangles are closely correlated with symptoms of the disease and its progression.1 Pathology of neurofibrillary tangles is associated with abnormal aggregation of tau protein. Tau protein is associated with microtubules and stabilizes them after phosphorylation. Microtubules are fulfilling the role of the cytoskeleton of the neuron. They are involved in the transport of vital substances from the cell center towards the end of the axon and back.

 

In Alzheimer's Disease, tau protein undergoes excess phosphorylation, due to which its threads begin to merge and form neurofibrillary tangles within nerve cells. This causes the destruction of microtubules and the collapse of the transport system within the neuron.2,3 Initially, this leads to disruption of the biochemical signals transmission between cells, and then to their death.4

 

It has been shown that GSK-3β (glycogen synthase kinase-3β) is a key factor in the phosphorylation of tau protein,5 its increased activity leading to pathologies of neurofibrillary tangles and, consequently, to neurodegenerative changes in the brain.6,7 In this connection, the search for effective inhibitors of GSK-3β is a very important and urgent task, for their further use in the treatment of Alzheimer's Disease. In recent years, an increasing number of works devoted to this subject has appeared.8-11

 

M. Saitoh and colleagues proposed GSK-3β derivatives of 2-mercapto-1,3,4-oxadiazole as inhibitors (Figure 1a),12 using the method of X-ray analysis. They found the place of binding and the position of the inhibitor in the active center of the enzyme.

 

In this paper, we have proposed N-amidoalkylated derivatives of 2-amino-1,3,4-oxadiazole as potential inhibitors of GSK-3β (Figure 1b). The search for compounds leaders has been based on the results of the molecular docking.13,14 The structures of the compounds for the prediction have been taken from our virtual library, their general synthesis methodology having been developed by us earlier.15,16

 

 

Fig. 1: The structures of some inhibitors of GSK-3β (a)12 and structures of N-amidoalkylated derivatives of 2-amino-1,3,4-oxadiazole (b).15

 

MATERIAL AND METHODS:

Molecular docking studies:

We have carried out geometry optimization of analyzed structures within PM3 semi-empirical method, and GSK-3β molecular docking using software ArgusLab 4.0.1.17 Previously, this software package was successfully used to solve similar problems.18-27

 

The three-dimensional crystal structure of co-crystallizer GSK-3β and 2-(benzo[d][1,3]dioxol-5-yl)-5-((3-fluoro-4-methoxybenzyl)thio)-1,3,4-oxadiazole (1) (PDB ID: 3F7Z) has been loaded in PDB format from the data bank of protein molecules (http://www.rcsb.org). The protein molecule is symmetrical and contains two active sites, and consequently, co-crystallizer contains two molecules of inhibitor (1). To be able to assess the root-mean-square deviation of atomic positions (RMSD) one molecule from (1) was previously removed. Crystalline inclusions PTR 216 and PTR 560 were also removed for ease of operation. Before the molecular docking, the hydrogen atoms were added throughout the protein structure. The molecules of crystal water were not removed from the binding site since they were involved in the binding of the inhibitor by means of hydrogen bonds.12

 

On the basis of remaining inhibitor molecule (1) (code in co-crystallizer 3000 340), we have created ligand group named Ligand_X-ray. A three-dimensional model of the binding site has been created on the basis of this group, its dimensions being calculated automatically and being along the X-axis - 19.967, Y-axis - 15.898 and the Z-axis-17.203 Å. Docking has been done with a flexible ligand. A semi-empirical AScore function has been used to the scoring procedure, based on the XScore function.28 The cell resolution has been set at 0.250 Å. The calculation type has been Dock; Docking Engine - ArgusLab. Visualization of the results has been carried out using program PyMOL.29

 

Chemical synthesis:

IR spectra were recorded in KBr pellets using a Spectrum BX II spectrometer. FAB mass spectra were recorded on a VG7070 instrument. Desorption of ions from the samples in meta-nitrobenzyl alcohol was carried out with a beam of argon atoms having an energy of 8 keV.1H NMR (400 MHz) and 13C NMR (100 MHz) spectra were recorded for solutions in DMSO-d6 on a Varian VXR-400 spectrometer. Elemental analysis was performed on a LECO CHNS-900 instrument. Control of the reactions and the purity of compounds were performed by TLC on Silufol UV-254 plates eluting with chloroform/acetone (3:1).

 

2,4-Dichloro-N-(2,2,2-trichloro-1-isothiocyanatoethyl)benzamide (4.37b). 12 mmol of thionyl chloride was added to the suspension of 10 mmol (3.37 g) 2,4-dichloro-N-(2,2,2-trichloro-1-hydroxyethyl)benzamide (4.37а)30 in 30-35 mL of CCl4. The mixture was refluxed for 1-1.2 hours. After completion of the reaction, the solution was still warm filtered, and the filtrate was evaporated on a rotary evaporator. The residue after evaporation was treated with hexane (2×10 mL), filtered and dissolved in 30-35 mL of anhydrous acetonitrile. 10 mmol (0.97 g) of carefully dried KSCN was added in portions to the resulting solution. The reaction mixture was being stirred for 1.5-2 hours. The precipitated KCl was filtered off, the filtrate was evaporated on a rotary evaporator without raising the heating temperature above 55-60 °C. The residue after evaporation was treated with water (3×50 mL), filtered and dried at room temperature for 48 hours. The product was recrystallized from acetonitrile. Light yellow crystals; yield 78% (2.95 g); mp. 113-115 °C (MeCN); Rf = 0.72. 1H NMR: δ 10.39 (d, J = 8.8 Hz, 1Н, NH), 7.76 (s, 1H, Harom.), 7.57-7.55 (m, 1H, Harom.), 7.50-7.48 (m, 1H, Harom.), 6.68 (d, J = 8.8 Hz, 1H, CH). 13C NMR: δ 165.6 (C=O), 140.7 (-N=C=S), 135.4, 133.5, 131.2, 130.3, 129.2, 127.3, (arom.), 98.8 (CCl3), 72.4 (CH). IR: νmax 3226, 3188 (NH), 3024, 2927, 2852 (CH), 2033 (-N=C=S), 1667 (C=O), 1591, 1533, 1283, 1220, 1163, 1129, 1001, 813, 795, 624, 509 cm-1. MS (FAB): m/z 377 [M+H]+. Anal. Calcd (%) for C10H5Cl5N2OS (378.47): C, 31.74; H, 1.33; Cl, 46.83; N, 7.40; S, 8.47. Found: C, 31.71; H, 1.35; Cl, 46.87; N, 7.44; S, 8.51.

 

2,4-Dichloro-N-(2,2,2-trichloro-1-(2-(4-methylbenzoyl)hydrazine-1-carbothioamido)ethyl)benzamide (4.37d). An equimolar amount (1.50 g) of para-toluic hydrazide in 12-15 mL of EtOH was added to the solution of 10 mmol (3.79 g) of isothiocyanate (4.37a) in 18-20 mL of EtOH. The mixture was reflux for 2-3 minutes and left for 24 hours. The precipitate, which formed, was filtered off, washed with 10-12 mL of EtOH and dried at room temperature for 48 hours. The product was recrystallized from acetonitrile. White crystals; yield 83% (4.39 g); mp. 157-159 °C (MeCN); Rf = 0.64. 1H NMR: δ 10.63 (brs, 1Н, NH), 10.29 (brs, 1Н, NH), 9.67 (d, J = 7.8 Hz, 1H, NH), 9.32 (d, J = 8.3 Hz, 1Н, NH), 7.83-7.75 (m, 3H, Harom.), 7.56-7.54 (dd, J = 7.8, 8.3 Hz, 1H, CH), 7.50-7.41 (m, 2H, Harom.), 7.33-7.31 (m, 2H, Harom.), 2.36 (s, 3Н, СН3). 13C NMR: δ 184.54 (C=S), 166.12, 164.13 (C=O), 142.40, 135.52, 133.80, 131.28, 130.34, 129.57, 129.54, 128.97, 128.88, 127.62 (arom.), 101.55 (CCl3), 69.45 (CH), 21.04 (CH3). IR: νmax 3398, 3324 (NH), 2918, 2858, 2784 (CH), 1712, 1659 (C=O), 1604, 1542, 1448, 1314, 1136, 1092, 1024, 832 cm-1. MS (FAB): m/z 527 [M+H]+. Anal. Calcd (%) for C18H15Cl5N4O2S (528.65): C, 40.90; H, 2.86; Cl, 33.53; N, 10.60; S, 6.06. Found: C, 40.87; H, 2.85; Cl, 33.57; N, 10.64; S, 6.11.

 

2,4-Dichloro-N-(2,2,2-trichloro-1-((5-(p-tolyl)-1,3,4-oxadiazol-2-yl)amino)ethyl)benzamide (4.37). 11 mmol (2.27 g) of DCC and 50-55 mL of anhydrous acetonitrile were added to 10 mmol (5.29 g) of compound (4.37d). The mixture was reflux for 20-30 minutes. The completion of the reaction was determined by TLC method. The reaction mixture was cooled for one hour at room temperature; the precipitate was filtered off, washed with acetonitrile (2×5 mL) and dried. The product was recrystallized from ethyl alcohol. White crystals; yield 63% (3.12 g); mp. 230-232 °C (EtOH); Rf = 0.91. 1H NMR: δ 9.32 (brs, 1H, NH), 8.74 (brs, 1H, NH), 7.77 (d, J = 7.8 Hz, 2H, Harom.), 7.50-7.48 (m, 2H, Harom.), 7.40-7.38 (m, 1H, Harom.), 7.29 (d, J = 7.8 Hz, 2H, Harom.), 6.53 (brs, 1H, CH), 2.41 (s, 3H, CH3). 13C NMR: δ 164.73 (C=O), 158.44, 140.09 (C=N), 135.16, 133.78, 133.75, 131.50, 130.41, 129.21, 128.87, 126.60, 125.17, 121.22 (arom.), 100.39 (CCl3), 70.10 (CH), 21.02 (CH3). IR: νmax 3328 (NH), 2937, 2863, 2772 (CH), 1665 (C=O), 1624, 1540, 1442, 1300, 1132, 1097, 1022, 830 cm-1. MS (FAB): m/z 493 [M+H]+. Anal. Calcd (%) for C18H13Cl5N4O2 (494.58): C, 43.71; H, 2.65; Cl, 35.84; N, 11.33. Found: C, 43.68; H, 2.63; Cl, 35.87; N, 11.37..

 

RESULTS AND DISCUSSION:

The active GSK-3β site is a large lipophilic pocket with small polar regions at opposite ends. In these areas, there are molecules of crystalline water, which take an active part in ligand-protein interactions. In carrying out molecular docking, we have used 2-(benzo[d][1,3]dioxol-5-yl)-5-((3-fluoro-4-methoxybenzyl)thio)-1,3,4-oxadiazole (1) as a reference. According to X-ray diffraction analysis, the molecule of compound (1) interacts additionally with the active site of GSK-3β due to the formation of a complex system of intermolecular hydrogen bonds involving water molecules H2O 3121 and H2O 3120 and the Nitrogen atom of pyridine type of N(4) 1,3,4-oxadiazole rings. The Oxygen atom of the benzodioxole cycle and the amino acid valine 135 also form the hydrogen bond, the bond length is 2.887 Å. The calculated energy of inhibitor binding (1) with the active site of the enzyme is -9.8475 kcal/mol, the calculation time - 5 seconds. The calculated position of the inhibitor in the active site of the enzyme is similar to the results obtained by X-ray analysis (Figure 2), root-mean-square deviation of atomic positions (RMSD) is 1.4 Å. According to molecular docking data, the molecule of compound (1) interacts additionally with the active site of GSK-3β due to the formation of a complex system of intermolecular hydrogen bonds involving water molecules H2O 3121 and H2O 3120 and the Nitrogen atom of pyridine type of N(4) 1,3,4-oxadiazole rings. The Nitrogen atom of pyridine type of N(3) 1,3,4-oxadiazole ringsand the amino acid asparagine 200 also form the hydrogen bond, the bond length is 3.316 Å.

 

 

a)

 

b)

Fig. 2: Position of compound (1) in active site of GSK-3β according to X-ray analysis data (a)12 and molecular docking (b)

 

The results of geometry optimization of N-amidoalkylated derivatives of 2-amino-1,3,4-oxadiazoles indicate their structural similarity to compound (1) (Figure 3). The total energy of (3.1)-(3.42) compounds ranges from -107897.1456 to -62791.5327 kcal/mol, and compounds (4.1)-(4.42) - from -132174.4408 to -87070.1177 kcal/mol.

 

According to the molecular docking, compounds (3.25), (4.37) have formed the most stable complexes with GSK-3β. The energy of complexes with other investigated structures is somewhat higher (Table 1). Compounds (3.1)-(3.7), (3.9), (3.11), (3.12), (3.19), (3.26), (3.31), (3.32), (3.34), (4.1), (4.2), (4.5), (4.6), (4.8), (4.12), (4.17), (4.18), (4.25), (4.31), (4.32), (4.35) are inferior inhibitor (1) to the strength of the complex formed with the enzyme. Root-mean-square deviation of atomic positions has been calculated only for the 1,3,4-oxadiazole ring and the aromatic moiety adjacent to it in the fifth position.

 

 

 

Fig. 3: Comparison of the three-dimensional structures of the molecules of inhibitor (1) (green), compounds (3.25) (pink) and (4.37) (orange)

N-(((5-(2-Bromophenyl)-1,3,4-oxadiazol-2-yl)amino)methyl)benz-amide (3.25) effectively binds to GSK-3β by the formation of two intermolecular hydrogen bonds (Figure 4a). Hydrogen bonds are formed by 1) The Nitrogen atom N(3) of the 1,3,4-oxadiazole cycle and -NH group of valine (135), bond length 2.988 Å; 2) The Hydrogen atom of the amine moiety and the Oxygen atom of valine (135), bond length 2.853 Å. The molecule of 2,4-dichloro-N-(2,2,2-trichloro-1-((5-(p-tolyl)-1,3,4-oxadiazol-2-yl)amino)ethyl)benzamide (4.37) is additionally fixed in the active center of InhA enzyme due to the complex system of intermolecular hydrogen bonds involving the molecules of crystalline water – H2O 3070, H2O 3071 and H2O 3145 (Figure 4b).

 

 

a)

 

 

 

 

b)

Fig. 4: Position of N-(((5-(2-bromophenyl)-1,3,4-oxadiazol-2-yl)amino)methyl)benzamide (3.25) (a) and 2,4-dichloro-N-(2,2,2-trichloro-1-((5-(p-tolyl)-1,3,4-oxadiazol-2-yl)amino)ethyl)benzamide (4.37) (b) in GSK-3β active site according to the results of molecular docking.

 

 


Table 1: The results of molecular docking of N-amidoalkylated derivatives of 2-amino-1,3,4-oxadiazole with GSK-3β.

 

 

Comp.

R

Ar*

E, kcal/mol

RMSD**, Å

Comp.

R

Ar*

E, kcal/mol

RMSD**, Å

3.1

CH3

C6H5

-9.5341

5.9

4.1

CH3

C6H5

-9.5246

5.4

3.2

CH3

4-CH3C6H4

-9.1845

5.7

4.2

CH3

4-CH3C6H4

-9.1353

5.6

3.3

CH3

4-CH3OC6H4

-9.1672

5.9

4.3

CH3

4-CH3OC6H4

-10.0572

5.0

3.4

CH3

3-BrC6H4

-9.5864

4.9

4.4

CH3

3-BrC6H4

-9.9083

4.7

3.5

CH3

4-C5H4N

-9.2717

6.6

4.5

CH3

4-C5H4N

-9.4909

5.5

3.6

CH3

2-NO2C6H4

-9.4257

8.5

4.6

CH3

2-NO2C6H4

-9.6077

7.3

3.7

CH3

4-NO2C6H4

-8.9518

5.8

4.7

CH3

4-NO2C6H4

-10.1108

4.5

3.8

C2H5

C6H5

-9.9624

4.8

4.8

C2H5

C6H5

-9.3602

5.2

3.9

C2H5

4-CH3C6H4

-9.4033

5.5

4.9

C2H5

4-CH3C6H4

-10.0348

5.3

3.10

C2H5

4-CH3OC6H4

-10.0251

4.3

4.10

C2H5

4-CH3OC6H4

-10.1033

4.7

3.11

C2H5

3-BrC6H4

-9.1475

5.5

4.11

C2H5

3-BrC6H4

-9.8575

6.2

3.12

C2H5

4-C5H4N

-9.1724

6.0

4.12

C2H5

4-C5H4N

-9.2754

5.8

3.13

C2H5

2-NO2C6H4

-10.3423

4.8

4.13

C2H5

2-NO2C6H4

-10.4833

6.0

3.14

C2H5

4-NO2C6H4

-10.7845

5.7

4.14

C2H5

4-NO2C6H4

-10.1045

4.4

3.15

CH2=CH

C6H5

-10.4878

5.4

4.15

CH2=CH

C6H5

-10.1007

6.0

3.16

CH2=CH

4-CH3C6H4

-10.6742

5.8

4.16

CH2=CH

4-CH3C6H4

-9.8506

5.9

3.17

CH2=CH

4-CH3OC6H4

-10.1714

4.9

4.17

CH2=CH

4-CH3OC6H4

-9.3440

4.8

3.18

CH2=CH

3-BrC6H4

-9.8997

6.8

4.18

CH2=CH

3-BrC6H4

-9.0181

3.6

3.19

CH2=CH

4-C5H4N

-9.4347

8.4

4.19

CH2=CH

4-C5H4N

-9.7747

8.0

3.20

CH2=CH

2-NO2C6H4

-10.3104

4.8

4.20

CH2=CH

2-NO2C6H4

-10.3057

4.8

3.21

CH2=CH

4-NO2C6H4

-9.9920

5.5

4.21

CH2=CH

4-NO2C6H4

-9.8240

5.5

3.22

C6H5

C6H5

-10.5105

4.8

4.22

C6H5

C6H5

-10.3832

5.0

3.23

C6H5

4-CH3C6H4

-9.9624

5.6

4.23

C6H5

4-CH3C6H4

-10.5441

5.4

3.24

C6H5

4-CH3OC6H4

-10.0560

6.0

4.24

C6H5

4-CH3OC6H4

-9.6651

6.1

3.25

C6H5

3-BrC6H4

-11.1231

4.8

4.25

C6H5

3-BrC6H4

-9.1442

5.4

3.26

C6H5

4-C5H4N

-9.1556

6.0

4.26

C6H5

4-C5H4N

-10.0332

3.9

3.27

C6H5

2-NO2C6H4

-10.3943

5.1

4.27

C6H5

2-NO2C6H4

-10. 4127

5.1

3.28

C6H5

4-NO2C6H4

-10.1005

5.7

4.28

C6H5

4-NO2C6H4

-10.1956

5.8

3.29

4-CH3C6H4

C6H5

-10.1441

5.9

4.29

4-CH3C6H4

C6H5

-10.1865

5.7

3.30

4-CH3C6H4

4-CH3C6H4

-9.7713

4.8

4.30

4-CH3C6H4

4-CH3C6H4

-10.1542

5.9

3.31

4-CH3C6H4

4-CH3OC6H4

-9.2817

3.9

4.31

4-CH3C6H4

4-CH3OC6H4

-9.2092

6.7

3.32

4-CH3C6H4

3-BrC6H4

-9.0918

7.4

4.32

4-CH3C6H4

3-BrC6H4

-9.2605

8.3

3.33

4-CH3C6H4

4-C5H4N

-10.1205

4.6

4.33

4-CH3C6H4

4-C5H4N

-10.8103

4.1

3.34

4-CH3C6H4

2-NO2C6H4

-9.4644

5.7

4.34

4-CH3C6H4

2-NO2C6H4

-9.9763

4.9

3.35

4-CH3C6H4

4-NO2C6H4

-10.1077

5.8

4.35

4-CH3C6H4

4-NO2C6H4

-9.2918

6.6

3.36

2,4-Cl2C6H3

C6H5

-10.1203

4.3

4.36

2,4-Cl2C6H3

C6H5

-10.1033

4.9

3.37

2,4-Cl2C6H3

4-CH3C6H4

-9.8545

6.1

4.37

2,4-Cl2C6H3

4-CH3C6H4

-11.8573

2.0

3.38

2,4-Cl2C6H3

4-CH3OC6H4

-9.9372

5.1

4.38

2,4-Cl2C6H3

4-CH3OC6H4

-9.9936

5.6

3.39

2,4-Cl2C6H3

3-BrC6H4

-10.3092

5.0

4.39

2,4-Cl2C6H3

3-BrC6H4

-10.3432

4.0

3.40

2,4-Cl2C6H3

4-C5H4N

-10.2147

5.2

4.40

2,4-Cl2C6H3

4-C5H4N

-9.8542

5.1

3.41

2,4-Cl2C6H3

2-NO2C6H4

-10.1784

5.3

4.41

2,4-Cl2C6H3

2-NO2C6H4

-10.1831

4.7

3.42

2,4-Cl2C6H3

4-NO2C6H4

-10.5879

6.0

4.42

2,4-Cl2C6H3

4-NO2C6H4

-10.1542

4.3

* 4-C5H4N – pyridyl;

** For the structures containing the pyridine ring we have calculated root-mean-square deviation of atomic positions only for the 1,3,4-oxadiazole ring.

 


The compound (3.25) had been obtained earlier.16 The compound (4.37) was not described in the literature before. Its synthesis was carried out according to scheme 1. 2,4-Dichloro-N-(2,2,2-trichloro-1-isothiocyanatoethyl)benzamide (4.37b) was obtained based on 2,4-dichloro-N-(2,2,2-trichloro-1-hydroxyethyl)benzamide (4.37a).30 The preparation of (4.37b) was carried out in acetonitrile, which greatly facilitated the isolation of the product and allowed it to be obtained in high yields and of sufficient purity for use in further conversions without further purification. Addition of para-toluic hydrazide (4.37c) to isothiocyanate (4.37b) resulted in the formation of 2,4-dichloro-N-(2,2,2-trichloro-1-(2-(4-methylbenzoyl)hydrazine-1-carbothioamido)ethyl)benzami-de (4.37d). To complete the oxadiazole cycle, a 10% excess of dicyclohexylcarbodiimide (DCC) was used as the dehydrosulfinating agent. The reaction was carried out during refluxing for 20-30 minutes without formation of by-products, and the compound (4.37) was obtained in high yields.

 

It should be noted that 2,4-dichloro-N-(2,2,2-trichloro-1-hydroxyethyl)benzamide (4.37a) and its analogues thanks to their easy accessibility and polyfunctionality, they are successfully used in the synthesis of heterocyclic compounds,15,31-37 pesticides,38,39 accelerators of rubbers vulcanization,40 etc.41 These compounds are of particular interestas synthons for the preparation of potential medications, for example, potassium channel activators,42 means for combating schistosomiasis,43 anticonvulsants,44,45 as well as Salubrinal and its analogues.46-48


 

 

Scheme 1. Synthesis of 2,4-dichloro-N-(2,2,2-trichloro-1-((5-(p-tolyl)-1,3,4-oxadiazol-2-yl)amino)ethyl)-benzamide (4.37). Reagents and conditions: a) chloral carboxamide (4.37a), SOCl2, CCl4, reflux - 1-1.2 h; b) KSCN, acetonitrile, stirring - 1.5-2 h; c) isothiocyanate (4.37b), p-toluic hydrazide (4.37c), EtOH, reflux - 2-4 minutes; d) acetonitrile, DCC, reflux - 20-30 minutes.

 


The structure of the compounds obtained is confirmed by complex spectral studies. Thus, in the IR spectra of the compounds (4.37b), (4.37d) and (4.37) in the 3398-3264 cm-1 region, intense absorption bands of symmetric and antisymmetric stretching vibrations of NH groups have been detected, these bands being most intense and represented by several peaks for the compound (4.37d). The vibrations of the C=O group of the amide fragment in these compounds and for the compound (4.37d) - the hydrazide fragment as well, lie in the region of 1712-1654 cm-1. IR spectrum of the compound (4.37b) is also characterized by an intense band at 2054 cm-1, which corresponds to vibrations of the isothiocyanate group.49

In 1Н NMR spectra, the signal of the methine proton located in the trichloromethyl group is in the region of 7.58-6.53 ppm and is manifested as the doublet for the compound (4.37b), the doublet of doublets for the compound (4.37d), and the broadened singlet - for (4.37). The proton signal of amide, hydrazide and amino groups is observed in the region of 10.65-9.31 ppm. In 13С NMR spectrum of the compounds (4.37) in the region of 185-181 and 166-165 ppm, there are no signals C=S and C=O (hydrazide) carbons, characteristic for the starting compound (4.37d). In this case, carbon signals of two C=N groups located in the region of 159-140 ppm are observed. The presence of the signal of the amide carbon atom (C=O) in the region of 165-164 ppm, CH - in the region of 73-69 ppm and CCl3 - in the region of 102-99 ppm is characteristic in 13С NMR spectra of all compounds.

 

The mass spectra of electron impact (EI) turned out to be poorly informative because of the high lability of the compounds (4.37b), (4.37d). Thus, for the compound (4.37d), the intensity of the molecular ion peak did not exceed 1.0%, as for the compound (4.37b) - it was not observed at all. FAB Spectra were more informative.

 

CONCLUSION:

In this study, we have carried out in silico modeling of enzyme inhibition GSK-3β with ArgusLab 4.0.1 software package. N-amidoalkylated derivatives of 2-amino-1,3,4-oxadiazole have been proposed as potential inhibitors. It has been shown that the structures being studied mainly form more stable complexes with the enzyme compared to the known inhibitor. Two compounds leaders have been selected on the basis of the results of molecular docking - (3.25), (4.37). Four-step synthesis of the compound (4.37) has been carried out. They can be recommended for further studies in the treatment of Alzheimer's disease.

 

CONFLICT OF INTEREST:

The authors declare no conflict of interest.

 

REFERENCES:

1.     Hasegawa M. Molecular Mechanisms in the Pathogenesis of Alzheimer's disease and Tauopathies-Prion-Like Seeded Aggregation and Phosphorylation. Biomolecules 2016; 6(2): E24. doi: 10.3390/biom6020024

2.     Canter RG, Penney J, Tsai L-H. The road to restoring neural circuits for the treatment of Alzheimer's disease. Nature 2016; 539(7628): 187-196. doi: 10.1038/nature20412

3.     Iqbal K, Alonso AC, Chen S, Chohan MO, El-Akkad E, Gong CX, Khatoon S, Li B, Liu F, Rahman A, Tanimukai H, Grundke-Iqbal I. Tau pathology in Alzheimer disease and other tauopathies. Biochim. Biophys. Acta. 2005; 1739(2-3): 198-210. doi: 10.1016/j.bbadis.2004.09.008

4.     Chun W, Johnson GV. The role of tau phosphorylation and cleavage in neuronal cell death. Front. Biosci. 2007; 12(2): 733-756. doi: 10.2741/2097

5.     Ishiguro K, Takamatsu M, Tomizawa K, Omori A, Takahashi M, Arioka M, Uchida T, Imahori K. Tau protein kinase I converts normal tau protein into A68-like component of paired helical filaments. J. Biol. Chem. 1992; 267(15): 10897-10901.

6.     Pei JJ, Tanaka T, Tung YC, Braak E, Iqbal K, Grundke-Iqbal I. Distribution, Levels, and Activity of Glycogen Synthase Kinase-3 in the Alzheimer Disease Brain. J. Neuropathol. Exp. Neurol. 1997; 56(1): 70-78. doi: 10.1097/00005072-199701000-00007

7.     Pei JJ, Braak E, Braak H, Grundke-Iqbal I, Iqbal K, Winblad B, Cowburn RF. Distribution of Active Glycogen Synthase Kinase 3β (GSK-3β) in Brains Staged for Alzheimer Disease Neurofibrillary Changes. J. Neuropathol. Exp. Neurol. 1999; 58(9): 1010-1019. doi: 10.1097/00005072-199909000-00011

8.     Eldar-Finkelman H, Licht-Murava A, Pietrokovski Sh, Eisenstein M. Substrate Competitive GSK-3 Inhibitors - strategy and Implications. Biochim. Biophys. Acta. 2010; 1804(3): 598-603. doi: 10.1016/j.bbapap.2009.09.010

9.     Wagner FF, Bishop JA, Gale JP, Shi X, Walk M, Ketterman J, Patnaik D, Barker D, Walpita D, Campbell AJ, Nguyen Sh, Lewis M, Ross L, Weïwer M, Frank An W, Germain AR, Nag PP, Metkar Sh, Kaya T, Dandapani S, Olson DE, Barbe A-L, Lazzaro F, Sacher JR, Cheah JH, Fei D, Perez J, Munoz B, Palmer M, Stegmaier K, Schreiber SL, Scolnick E, Zhang Y-L, Haggarty SJ, Holson EB, Pan JQ. Inhibitors of Glycogen Synthase Kinase 3 with Exquisite Kinome-Wide Selectivity and Their Functional Effects. ACS Chem. Biol. 2016; 11(7): 1952-1963. doi: 10.1021/acschembio.6b00306

10.   Licht-Murava A, Paz R, Vaks L, Plotkin B, Eisenstein M, Eldar-Finkelman H. A unique type of GSK-3 inhibitor brings new opportunities to the clinic. Sci. Signal. 2016; 9(454): ra110. doi: 10.1126/scisignal.aah7102

11.   Palomo V, Martinez A. Glycogen synthase kinase 3 (GSK-3) inhibitors: a patent update (2014-2015). Expert Opin. Ther. Pat. 2017; 27(6): 657-666. doi: 10.1080/13543776.2017.1259412.

12.   Saitoh M, Kunitomo J, Kimura E, Hayase Y, Kobayashi H, Uchiyama N, Kawamoto T, Tanaka T, Mol CD, Dougan DR, Textor GS, Snell GP, Itoh F. Design, synthesis and structure–activity relationships of 1,3,4-oxadiazole derivatives as novel inhibitors of glycogen synthase kinase-3β. Bioorg. Med. Chem. 2009; 17(5): 2017-2029. doi: 10.1016/j.bmc.2009.01.019

13.   Young DC. Computational drug design. New Jersey: John Wiley & Sons, Inc., Hoboken. 2009.

14.   Holtje HD, Sippl W, Rognan D, Folkers R. Molecular Modeling. Basic Principles and Applications. Weinheim: Wiley-VCH Verlag GmbH & Co. KGaA; 2008.

15.   Zadorozhnii PV, Kiselev VV, Kharchenko AV. Synthesis of Nitrogen-Containing Heterocycles Based on N-(Isothiocyanatoalkyl)carboxamides. In: Novikov V. Ed., Modern Directions in Chemistry, Biology, Pharmacy and Biotechnology. Lviv: Lviv Polytechnic Publishing House; 2015.

16.   Zadorozhnii PV, Kiselev VV, Chernous SY, Kharchenko AV, Okhtina OV. Synthesis of amidoalkylation 2-amino-1,3,4-oxadiazole derivatives (In Ukrainian). Vopr Khim Khim Tekhnol. 2012; 6: 30-32.

17.   Thompson M. ArgusLab 4.0.1., Planaria software LLC, Seattle, Wash, USA, 2004. (http://www.arguslab.com)

18.   Mohammadi-Farani A, Ahmadi A, Nadri H, Aliabadi A. Synthesis, docking and acetylcholinesterase inhibitory assessment of 2-(2-(4-Benzylpiperazin-1-yl)ethyl)isoindoline-1,3-dione derivatives with potential anti-Alzheimer effects. DARU J. Pharm. Sci. 2013; 21(1): 47. doi: 10.1186/2008-2231-21-47

19.   Aliabadi A, Mohammadi-Farani A, Ahmadvand MJ, Rahmani-Khajouei M. Synthesis, docking and acetylcholinesterase inhibitory evaluation of (E)-3-(4-(diethylamino)phenyl)-1-phenylprop-2-en-1-one derivatives with probable anti-Alzheimer effects. J. Rep. Pharm. Sci. 2017; 6(2): 134-141.

20.   Mahendran R, Jeyabasker S, Francis A, Manoharan Sh. Insights into the Identification of p38-alpha Mitogen activated Protein Kinase against Pyridazinopyridinone Derivatives in the Treatment of Rheumatoid Arthritis. Res. J. Pharm. Technol. 2017; 10(9): 2875-2879. doi: 10.5958/0974-360X.2017.00507.8

21.   Narayanan S, Ramchandran B, Rajendiran S, Chandra S, Tiwari A, Rajarethinam R, Kureeckal VR. Potent antitumour activity of (–)epigallocatechin gallate: indications from in vitro, in vivo and in silico studies. Curr. Sci. 2016; 110(2): 187-195. doi: 10.18520/cs/v110/i2/187-195

22.   Ikram H, Bano Kh, Jameel M, Azhar M, Saeed K, Sufian M. Conformational analysis and geometry optimization of apomorphine as an Anti-parkinsonian agent. Pak. J. Pharm. Sci. 2015; 28(5): 1685-1690.

23.   Nair NPr, Joy J, Kumar SS, Sathianarayanan S, Manakadan AA, Saranya TS. In-silico docking studies of coumarin derivatives as caspase 8 and PDE4 antagonist. Res. J. Pharm. Technol. 2016; 9(12): 2199-2204. doi:10.5958/0974-360X.2016.00445.5

24.   Dash R, Uddin MMN, Hosen SMZ, Rahim ZB, Dinar AM, Kabir MS, Sultan RA, Islam A, Hossain MK. Molecular docking analysis of known flavonoids as duel COX-2 inhibitors in the context of cancer. Bioinformation 2015; 11(12): 543-549. doi: 10.6026/97320630011543

25.   Zadorozhnii PV, Kiselev VV, Titova AE, Kharchenko AV, Pokotylo IO, Okhtina OV. Molecular Docking Studies of N-5-Aryl-1,3,4-oxadiazolo-2, 2-dichloroacetamidines as Inhibitors of Enoyl-ACP Reductase Mycobacterium tuberculosis. Res. J. Pharm. Technol. 2017; 10(4), 1091-1097. doi:10.5958/0974-360X.2017.00198.6

26.   Zadorozhnii PV, Kiselev VV, Teslenko NO, Kharchenko AV, Pokotylo IO, Okhtina OV, Kryshchyk OV. In Silico Prediction and Molecular Docking Studies of N-Amidoalkylated Derivatives of 1,3,4-Oxadiazole as COX-1 and COX-2 Potential Inhibitors. Res. J. Pharm. Technol. 2017; 10(11): 3957-3963. doi:10.5958/0974-360X.2017.00718.1

27.   Muthukumaran P, Rajiniraja M. In silico binding study of bioactive Hispolon and its Analogues to mycobacterial mtfabH. Res. J. Pharm. Technol. 2017, 10(7), 2229-2232. doi:10.5958/0974-360X.2017.00394.8

28.   Wang R, Lai L, Wang S. Further development and validation of empirical scoring functions for structure-based binding affinity prediction. J Comput. Aided Mol. Des. 2002; 16(1): 11-26.

29.   DeLano WL. The PyMOL Molecular Graphics System, DeLano Scientific: Palo Alto, CA, 2003. (http://www.pymol.org)

30.   Pokotylo IO, Zadorozhnii PV, Kiselev VV, Kharchenko AV. Solvent-free synthesis and spectral characteristics of N-(2,2,2-trichloro-1-hydroxyethyl)carboxamides. Chem. Data Collect. 2018; 15-16: 62-66. doi: 10.1016/j.cdc.2018.04.002

31.   Guirado A, López-Caracena L, López-Sánchez JI, Sandoval J, Vera M, Bautista D, Gálvez J. A new, high-yield synthesis of 3-aryl-1,2,4-triazoles. Tetrahedron 2016; 72(49): 8055-8060. doi: 10.1016/j.tet.2016.10.045

32.   Demydchuk BA, Kondratyuk KM, Kornienko AN, Brovarets VS, Vasylyshyn RYa, Tolmachev AA, Lukin O. A facile synthesis of 1,3-thiazole-4-sulfonyl chlorides. Synth. Commun. 2012; 42(19): 2866-2875. doi: 10.1080/00397911.2011.571356

33.   Zadorozhnii PV, Pokotylo IO, Kiselev VV, Kharchenko AV. New 2,2-dichloroacetamidines with heterocyclic fragments. Chem. Sci. Trans. 2016; 5(4): 1056-1062. doi: 10.7598/cst2016.1310 .

34.   Zadorozhnii PV, Kiselev VV, Pokotylo IO, Kharchenko AV. A new method for the synthesis of 4H-1,3,5-oxadiazine derivatives. Heterocycl. Commun. 2017; 23(5): 369-374. doi: 10.1515/hc-2017-0083

35.   Zadorozhnii PV, Kiselev VV, Pokotylo IO, Okhtina OV., Kharchenko AV. Synthesis and mass spectrometric fragmentation pattern of 6-(4-chlorophenyl)-N-aryl-4-(trichloromethyl)-4H-1,3,5-oxadiazin-2-amines. Heterocycl. Commun. 2018; 24(5): 273-278. doi: 10.1515/hc-2018-0082

36.   Zadorozhnii P, Kiselev V, Krvavych A, Novikov V, Kharchenko A. The molecular structure N-{2,2,2-trichloro-1-[(5-phenyl-1,3,4-thiadiazol-2-yl)amino]ethyl}acet- and Thioacetamide. Res. J. Pharm., Biol. Chem. Sci. 2015; 6(2): 689-695.

37.   Drach BS, Brovarets VS, Smolii OB. Syntheses of Nitrogen-Containing Compounds On the Basis of Amidoalkylation Agents. Naukova Dumka, Kiev, 1992.

38.   Larocca JP, Leonard JM, Weaver WE. The preparation and fungicidal activity of some amides of chloral and α,α,β-trichlorobutyraldehyde. J. Org. Chem. 1951; 16(1): 47-50. doi: 10.1021/jo01141a007

39.   Hudson HR, Mavrommatis ChN, Pianka M. Organophosphorus compounds as potential fungicides. Part V. The preparation and properties of some novel N,N,N’,N’-tetramethyl-N”-(1-substituted-2,2,2-trichloroethyl)phosphoric triamide. Phosphorus Sulfur Silicon Relat. Elem. 1996; 108(1-4): 141-153. doi: 10.1080/10426509608029647

40.   Podgornova VA, Farafontova VI, Borovkova GV, Ustavshchikov BF. Synthesis of N-substituted acrylamides. Part 2. Synthesis and use of N-(1-hydroxy-2,2,2-trichloroethyl)acryl- and -methacrylamide, new vulcanizing agents for rubbers. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 1999; 42: 58-61.

41.   Aizina JA, Rozentsveig I.B, Levkovskaya GG. A novel synthesis of chloroacetamide derivatives via C-amidoalkylation of aromatics by 2-chloro-N-(2,2,2-trichloro-1-hydroxyethyl)acetamide, Arkivoc 2011; 8: 192-199. doi: 10.3998/ark.5550190.0012.815 .

42.   Altenbach RJ, Bai H, Brioni JD, Carroll WA, Gopalakrishnan M, Gregg RJ, Holladay MW, Huang PP, Kincaid JF, Kort ME, Kym PhR, Lynch JK, Perez-Medrano A, Zhang H.Q. Potassium channel openers. U.S. Patent No. 2002/28836 A1, 2002; Chem. Abstr. 2002; 136: 231935.

43.   Schraufstaetter E, Goennert R. Alkyliden- und Aryliden-bis-chloracetamide, eine neue Gruppe gegen Bilharziose wirksamer Verbindungen. Z. Naturforsch. B. 1962; 17(8): 505-516. doi: 10.1515/znb-1962-0804

44.   Zadorozhnii PV, Kiselev VV, Pokotylo IO, Okhtina OV, Kharchenko AV. In silico prediction of anticonvulsant activity of N-(2,2,2-trichloro-1-hydroxyethyl)carboxamides. J. Chem. Pharm. Sci. 2017; 10(3): 1099-1105.

45.   Zadorozhnii PV, Popykhach NP, Kiselev VV, Pokotylo IO, Okhtina OV, Kharchenko A.V. In Silico Prediction of Anticonvulsant Activity of N-(2,2,2-Trichloro-1-hydroxyethyl)alkenyl- and –alkylarylcarboxamides. Res. J. Pharm. Technol. 2018; 11(2): 711-716. doi:10.5958/0974-360X.2018.00134.8

46.   Boyce M, Bryant KF, Jousse C, Long K, Harding HP, Sheuner D, Kaufman RJ, Ma D, Coen DM, Ron D, Yuan J. A Selective Inhibitor of eIF2alpha Dephosphorylation Protects Cells from ER Stress, Science 2005; 307 (5711): 935-939. doi: 10.1126/science.1101902

47.   Liu J, He K-L, Li X. SAR, cardiac myocytes protection activity and 3D-QSAR studies of salubrinal and its potent derivatives. Curr. Med. Chem. 2012; 19(35): 6072-6079. doi: 10.2174/0929867311209066072

48.   Long K, Boyce M, Lin H, Yuan J, Ma D. Structure-activity relationship studies of salubrinal lead to its active biotinylated derivative. Bioorg. Med. Chem. Lett. 2005; 15(17): 3849-3852. doi: 10.1016/j.bmcl.2005.05.120

49.   Nakanishi J. Infrared absorption spectroscopy. Holden-Day Inc., San Francisco, 1962.

 

 

 

 

Received on 16.12.2018          Modified on 05.01.2019

Accepted on 21.01.2019        © RJPT All right reserved

Research J. Pharm. and Tech 2019; 12(2):523-530.

DOI: 10.5958/0974-360X.2019.00092.1