Synthesis and Evaluation of Phenothiazine derivative for Anti-depressant activity

 

Nachiket S. Dighe1*, Renuka N.Barhate1, Ravindra B. Lawre2, Sunil A. Nirmal3

1Department of Pharmaceutical Chemistry, Pravara Rural College of Pharmacy, Loni, MS, India-413736

2Department of Pharmaceutics, Pravara Rural College of Pharmacy, Loni, MS, India-413736

3Department of Pharmacology, Pravara Rural College of Pharmacy, Loni, MS, India-413736

*Corresponding Author E-mail: nachiket1111@rediffmail.com

 

 

ABSTRACT:

This study was designed to synthesize, characterize and to evaluate the pharmacological activity of substituted phenothiazine  derivatives. Totally thirteen compounds, were synthesized by conventional method. Purity of the synthesized compounds was ascertained by TLC and melting point determination by open capillary tube method and they were characterized by IR and NMR spectroscopic methods. Antidepressant activity of all the synthesized compounds was evaluated by despair swim test by using Sprague Dawley Rats. Standard drug Imipramine was used as the control. In the results of the spectral study. all the compounds showed characteristic peak in IR and NMR spectroscopy. In the despair swim test, all the synthesized derivatives showed antidepressant activity. Among them three Compounds (A1, A3 A6 and A8) showed significant antidepressant activity comparing with control drug imipramine. These results are useful for the further investigation in the future.

 

KEYWORDS: Polyamide 6, Degradation mechanism, Flame retardants, Coats-Redfern method.

 

 


1. INTRODUCTION:

Current treatments for depression either fail to produce recovery or induce unwanted side effects. So there is still a large unmet clinical need(1-2). The heterocyclic compounds which contain nitrogen and sulphur possess an enormous significance in the field of medicinal chemistry.(10) The main aims in the development of new antidepressants were greater efficacy, absence of side effects, lack of toxicity in over dose and earlier onset of action(3).

 

Elaborate research work has been carried out in the past and continuing in the present to synthesize new compounds to meet this depression. The forced swim test (behavioral despair test) and tail suspension test in the rat are widely used for the initial screening of antidepressants. These tests have good predictive validity and allow rapid and economical detection of substances with potential antidepressant like activity. The tests are base on the same principle: measurement of the duration of immobility when rodents are exposed to an inescapable situation. The majority of clinically used antidepressants decrease the duration of immobility(4). Depression is a serious medical issue characterized by a variety of debilitating symptoms, such as persistent sadness and anxiety, chronic fatigue, feelings of worthlessness, disturbances in cognitive functioning and thoughts and attempts of suicide(5). Depression has been determined to be the leading cause of disability and the 4th leading contributor to the global burden of disease and is characterized by relapse, recurrence and chronicity(6). Antidepressants are the drugs used to treat depression thereby elevates mood and modifies the behavior. Half a century ago, antidepressants were discovered by serendipity(7).

 

As estimated by WHO, depression shall become the second largest illness in terms of morbidity by another decade in the world; already one out of every five women, and every twelve men have depression. Not only adults, but two percent of school children, and five percent of teenagers also suffer from depression, and these mostly go unidentified.[11]

 

To the present knowledge, antidepressant drugs used in the treatment of major depressive disorders are believed to act on the central monoaminergic systems mainly serotonin (5-hydroxytryptamine, 5-HT) and noradrenaline (NA) synaptic neurotransmissions. Selective serotonin reuptake inhibitors (SSRIs: paroxetine, fluoxetine, citalopram, escitalopram, fluvoxamine, sertraline) and noradrenaline reuptake inhibitors (NRIs: reboxetine, desipramine) are the most common prescribed antidepressant drugs.[12]

 

2. Materials and methods

2.1    Chemistry

Melting points were determined in open capillary method and are uncorrected. The 1H-NMR spectra were recorded on sophisticated multinuclear FT-NMR Spec-trometer model Advance-II (Bruker) using dimethylsulfoxide-d6 as solvent and tetramethylsilane as internal standard. IR spectra were recorded on Jasco FT-IR-spectrophotometer using KBr disc method. Antidepressant activity of all the synthesized compounds was evaluated by despair swim test using Sprague Dawley Rats.

 

2.2.1General procedure for the preparation of 7, 8 or 9 substituted aniline Benzoic acid derivatives (I)

Equimolar amount of substituted aniline was added to a chloro benzoic acid  in 20 mL of DMF and 0.1 percent of potassium  hydroxide solution and the reaction mixture was heated under refluxed  at about 80°C temperature, for 2 h. TLC indicated the end of reaction. The mixture was cooled by addition of a water/ice mixture. The solid was filtered in excellent yield .

 

2.2.2General procedure for the preparation of 7, 8 or 9 substituted 10H-phenothiazine 1 carboxylic acid derivatives (II)

Equimolar amount of 7, 8 or 9 substituted Anilino Benzoic acid was added to a solution of sulfur powder and iodine in 5 mL of ethanol. Reaction mixture was heated under reflux with stirring for about 2 h and poured into ice/water mixture. The precipitate was filtered and washed with cold water (A1-A13).    


2.3 Scheme:

 

 


2.3 Pharmacology:

Rat-Sprague Dawley (220-255 gm), 8-12 weeks old, was obtained from National Institute of Bioscience, Pune. They were housed in autoclaved polypropylene cages in groups of 2-3 rats per cage and kept in a room maintained at 19 to 25 0 C and humidity 45 to 65 % with a 12-h light/dark cycle. They were allowed to acclimatize for four days before the experiments and were given free access to Standard sterilized extruded rodent diet was provided ad libitum, Reverse Osmosis water treated with UV light was provided ad libitum in autoclaved polypropylene bottles and Autoclaved corn cob was used as bedding material.

 

All procedures of the present study was in accordance with the standard operating procedures of the Prado Pvt. Ltd. guidelines provided by the Committee for the Purpose of Control and Supervision of Experiments on Animals (CPCSEA) as published in The Gazette of India, December 15, 1998. Prior approval of the Institutional Animal Ethics Committee (IAEC) was obtained before initiation of the study (IAEC-13-002).

 

2.3.1 Antidepressant activity (forced swim test in rat):

Behavioral despair or forced swim test (FST) was proposed as a model to test antidepressant activity by Porsolt et al. (1977) (8-9). It was suggested that mice or rats when forced to swim in restricted space from where they cannot escape are induced to a characteristic behavior of immobility. This behavior reflects a state of despair which can be reduced by several agents which are therapeutically effective in human depression. The behavioral despair test is employed to assess the antidepressant activity of synthesized derivatives. Sprague-Dawley rats of 200-270 gm in a group of two each were used and on the first day of the experiment (pretest session), rats were individually placed in a cylindrical recipient (Plexiglass cylinder) of dimensions (diameter, 10 cm; height, 25 cm) containing 10 cm of water 25°C. The animals were left to swim for 6 min before being removed, dried and returned to their cages. The procedure was repeated 24 h later, in 5 min swim session (test session). The synthesized compounds (25 mg kg-1), and imipramine, as a reference antidepressant drug (25 mg kg-1) were suspended in a 0.5 % aqueous solution of Na CMC (Corboxy Methyl Cellulose). The drugs were given by gavage in a standard volume of 10ml/kg body weight, 1 h prior to the test. Control animals received 0.5 % aqueous solution of Na CMC (Corboxy Methyl Cellulose). This test was performed after 1 hr, 5 hrs and 24 hrs of dose administration. For individual animal video recording was made.Then, the rats were dropped individually into the Plexiglass cylinder and left in the water for 6 min. After the first 2 min of the initial vigorous struggling, the animals were immobile. An immobility time is the time spent by rat floating in water without struggling, making only those moment necessary to keep the head above the water. The total duration of immobility was recorded during the last 5 min of the 6 min test session.

 

3. RESULT AND DISCUSSION:

3.1    Chemistry

The structures, yields and melting points of the compounds have been given in the (Table 1).Melting points of the synthesized compounds were sharp indicating that the compounds were pure; the yield value of the compounds also suggested that the chemical methods were reliable for the synthesis of the compound. All spectral data were in accordance with assumed structures.

 

 


 

 

Table no. 01: Analytical and physicochemical data of the synthesized compounds (A1-A13)

Comp.

Mol. Formula

Mol. Wt.

M.P.

° C

Yield

%

Elemental analyses Calculated

C

H

N

A1

C13H8N2O4S

288.29

184

   65

54.16

2.80

9.72

A2

C13H8N2O4S

288.29

180

62

54.16

2.80

9.72

A3

C13H8N2O4S

288.29

180

65

54.16

2.80

9.72

A4

C13H8ClNO2S

277.72

174

52

56.22

2.90

5.04

A5

C13H7N3O6S

333.72

194

60

46.85

2.12

12.61

A6

C13H8ClNO2S

277.72

170

52

56.22

2.90

5.04

A7

C13H7Cl2NO2S

312.17

172

70

50.02

2.26

4.49

A8

C13H7CIN2O4S

 

322.72

193

60

48.38

2.19

8.68

A9

C13H7Cl2NO2S

312.17

170

   65

50.02

2.26

4.49

A10

C13H6BrN3O6S

 

412.17

192

62

37.88

1.47

16.19

A11

C13H8BrNO2S

322.17

180

65

48.46

2.50

4.35

A12

C13H7Cl2NO2S

312.17

170

52

50.02

2.26

4.49

A13

C13H8ClNO2S

277.72

175

60

56.22

2.90

5.04

 

 


Spectral Data:

A1: IR (KBr) cm-1: 3010.23 (Ar-CH str.),1715.11 (-C=O str.), ,3300.23(OH str),3100.11 (CH str),1360.35) (nitro symetry), . 1H NMR: 1.74(carboxylic acid),7.16(1H-phenothiazine),7.58-8.01(benzene),0.25 1-N=O=O from benzene

 

A2: IR (KBr) cm-1: 3050.23 (Ar-CH str.),1750.12 (-C=O str.), ,2510.23(OH str),3020.11 (CH str),1295.30 (nitro symetry),  1H NMR: 1.74(carboxylic acid),7.16(1H-phenothiazine),7.58-8.01(benzene) ,0.25 1-N=O=O from benzene

 

A3: IR (KBr) cm-11700.11 (-C=O str.), 1640.32 (-C=C str), 1H NMR1.74 (carboxylic acid),7.16(1H-phenothiazine),7.58-8.01(benzene) ,0.25 1-N=O=O from benzene

A4: IR (KBr) cm-13010.23 (Ar-CH str.), 1710.11 (-C=O str.), 1550.32 (-C=N str), 850.22 (-C-Cl str),: 1H NMR: 1.74(carboxylic acid),7.16(1H-phenothiazine),7.58-8.01(benzene),0.52 1-cl from 1 benzene

 

A5: IR (KBr) cm-1: 3010.23 (Ar-CH str.), 1682.11 (-C=O str.), 1355.40(nitro sym) 1H NMR: 1.74(carboxylic acid),7.16(1H-phenothiazine),7.58-8.01(benzene),0.39 (2H-N=O=O from benzene)

 

A6: IR (KBr) cm-1: 3012.25 (Ar-CH str.), 1702.21 (-C=O str)850.22(C-Clstr) 1H NMR: 1.74(carboxylic acid),7.16(1H-phenothiazine),7.58-8.01(benzene) ,0.52 1-cl from 1 benzene

 A7: IR (KBr) cm-1: 945.20 (-C-Cl str), 3110.23 (Ar-CH str.), 1682.11 (-C=O str.), 930.50 (C-Cl str) 1H NMR1.74 (carboxylic acid), 7.16(1H-phenothiazine), 7.58-8.01(benzene)0.01-0.06(2H 1 cl from benzene)

 

A8: IR (KBr) cm-1: 3010.23 (Ar-CH str.), 1682.11 (-C=O str.) 1550(nitro) 3616.11 (-OH str.). 1H NMR: 1.74(carboxylic acid),7.16(1H-phenothiazine),7.58-8.01(benzene)0.01-0.21 (2H- Cl from benzene),0.93 1-c(=o)o from benzene

 

A9: IR (KBr) cm-1:  3010.23 (Ar-CH str.), 1682.11 (-C=O str.), 3616.11 (-OH str.), 855.56(C-Cl str).1H NMR: 1.74(carboxylic acid), 7.16(1H-phenothiazine), 7.58-8.01(benzene) 0.01-0.06(2H 1 cl from benzene

 

A10: IR (KBr) cm-1: 3010.23 (Ar-CH str.), 1689.78 (-C=O str), 1460(nitro sym) 940.21. 1H NMR: 1.74(carboxylic acid), 7.16(1H-phenothiazine),7.58-8.01(benzene)

 

A11: IR (KBr) cm-1:3010.23 (Ar-CH str.), 1689.78 (-C=O str),  3600.12 (-OH str.), 940.21(C-Cl str) 1H NMR: 1.74(carboxylic acid),7.16(1H-phenothiazine), 7.58-8.01(benzene),0.17- 1 Br from benzene

A12: IR (KBr) cm-1:3210.23 (-CH=CH str.), 3020.23 (Ar-CH str.), 1750.78 (-C=O str),935.11 (C-Cl str). 1H NMR: 1.74(carboxylic acid), 7.16(1H-phenothiazine), 7.58-8.01(benzene) 0.01-0.06(2H 1 cl from benzene

 

A13: IR (KBr) cm-1: 3110.23 (Ar-CH str.),  1689.78 (-C=O str), 934.12(C-Cl str). 1H NMR: 1.74(carboxylic acid), 7.16(1H-phenothiazine), 7.58-8.01(benzene) 0.52 1-cl from 1 benzene.

 

3.2 Antidepressant Activity

All the synthesized compounds were subjected to antidepressant activity study on Sprague-Dawley rats by despair swim test. Imipramine was used as standard control. The animals show more stable levels of immobility during the last four minutes of the session. The results showed that all the compounds showed antidepressant activity. Among them three Compounds (A1, A3, A6 and A8) showed significant antidepressant activity comparing with standard control imipramine (Table 02).

 


 

 

Table 03: Antidepressant activities of the compounds

Compound code.

Immobility time

% Immobility

1 Hr

5 Hr

24 Hr

1 Hr

5 Hr

24 Hr

A1

162.5

162.5

172

97.15

89.56

88.82

A2

156.5

160

167.5

92.56

87.21

85.41

A3

176

175.5

184.5

102.84

96.58

95.01

A4

142.5

156

163.5

85.84

85.47

83.84

A5

144

158.5

163.5

87.72

86.84

83.84

A6

164

164

173

96.34

89.86

88.71

A7

145.5

158

167.5

83.59

86.57

85.89

A8

160.5

163.5

173

95.34

89.90

88.74

A9

169.5

178.5

184

97.54

97.80

94.35

A10

151.5

156

165

80.08

85.47

84.61

A11

169

170.5

178

99.68

97.09

91.88

A12

165

168.5

176

97.51

94.78

90.23

A13

170

179.5

182

98.25

95.06

92.82

Control

172

182.5

195

100

100

100

Imipramine (std.)

136.5

150.5

154.5

79.41

82.49

79.26

  

 


4. DISCUSSION:

Statistical evaluation of the equations is in accepted range. The correlation coefficient is high with less standard error. The residual value and residual variance for each series also is less indicating good predictive power of models. From equation  it is observed that two electronic parameters Dipole Moment Z Component (Whole Molecule) and VAMP HOMO (Whole Molecule) as well as one steric parameter Inertia Moment 2 Length (Whole Molecule) contribute (-0.227, –1.469 and – 0.414 respectively) negatively for the activity so electron withdrawing and less bulky groups may enhance the activity (% Immobility).

5. CONCLUSION:

We investigated the importance of functional group substitutions, in the structural framework of the compounds for their antidepressant activity. All compounds showed significant antidepressant activity at dose (25 mg/kg). The compounds A4, A5 and A7) showed better activity. Finally, the encouraging result of the antidepressant activity displayed by these compounds may be of interest for further structural modifications to the lead compound and next level studies in the hope of finding a new potent antidepressant prescription.

 

 

6. REFERENCES:

1.        Vincent Castagne., Paul Moser., Sylvain Roux., Roger D Porsolt., 2010.Rodent models of depression: Forced swim and tail suspension behavioral despair tests in rats and mice. Current Protocols in Pharmacology 49: 5.8.1-5.8.14.

2.        Slattery DA, Hudson AL, Nutt DJ. 2004 Invited review: The evolution of antidepressant mechanisms. Fundam. Clin. Pharmacol. 18: 1-21.

3.        Eleni Palazidou. 1997 Development of new antidepressants. Advances in Psychiatric treatment 3: 46-51.

4.        Vincent Castagne, Paul Moser, Sylvain Roux, Roger D Porsolt, 2010 Rodent models of depression: Forced swim and tail suspension behavioral despair tests in rats and mice. Current Protocols in Pharmacology 49: 5.8.1-5.8.14.

5.        Ray M Merrill., Arielle A Sloan., 2014. Associations between the uses antidepressants and other medications, open journal of depression 3(1):24-31

6.        Joanna L Iddon., Lee Grant., 2013. Behavioral and cognitive treatment interventions in depression: An analysis of the evidence base. Open Journal of Depression 2(2): 11-15.

7.        Benoit Petit – Demouliere, Franck Chenu., Michel Bourin., 2005. Forced swimming test in mice: A review of antidepressant activity. Psychopharmacology 177:245-255.

8.        Porsolt RD, Anton G, Blavet N, Jalfre M., 1978 Behavioural despair in rats: a new model sensitive to antidepressive treatments. Eur J Pharmacol,  47:379–391

9.        Porsolt RD, Bertin A, Jalfre M., 1977 Behavioural despair in mice: A primary screening test for antidepressants. Arch Int Pharmacodyn, 229:327-333.

10.     Girly vicent, B. Mathew Y, Jini Joseph, meena chandran, biological activity of thaiazine derivetivies ,international journal of pharmaceutical and  chemical sciences ISSN: 2277-5005,vol 3 (2) apr-june 2014,314-348.

11.      N.S. Dighe, P.S. Shinde, S.B. Vikhe, S.B. Dighe, D.S.Musmade, QSAR study, synthesis and antidepressant studies of some novel Schiff base derivatives of benzothiazepin, Bulgarian Chemical Communication, Volume 47, Number 3 (pp 837-843) 2015.

12.     Nachiket S. Dighe, Pankaj S.Shinde, Prajakta Tambe, Deepak S Musmade and Santosh B Dighe, Design, synthesis and antidepressant activity of some novel derivatives of benzothiazipine, International Journal of Pharmaceutical Chemistry.

 

 

 

 

 

Received on 12.12.2015         Modified on 22.12.2015

Accepted on 29.12.2015         © AJRC All right reserved

Asian J. Research Chem. 8(12): December 2015; Page 745-750

DOI: 10.5958/0974-4150.2015.00120.0