SYNTHESIS AND PHARMACOLOGICAL EVALUATION OF

SOME NOVEL BENZOTRIAZOLE DERIVATIVES CONTAINING PYRAZOLIDINEDIONE MOIETIES

SYNOPSIS FOR

M.PHARM DISSERTATION

SUBMITTED TO

RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES BANGALORE, KARNATAKA

BY

NATESH N N

I M.PHARM (2009-10)

DEPARTMENT OF PHARMACEUTICAL CHEMISTRY

M.S. RAMAIAH COLLEGE OF PHARMACY

BANGALORE-560054

RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES, BANGALORE, KARNATAKA

ANNEXURE II

PROFORMA FOR REGISTRATION OF SUBJECT

FOR DISSERTATION

1. / NAME OF THE CANDIDATE AND ADDRESS / NATESH N N,
S\O NANJUNDAIAH SETTY N S,
H.NO 33 TRINETHRA NILAYA, CHURCH ROAD, NEAR SAINT THOMAS PUBLIC SCHOOL, H.A.L THIRD STAGE NEW THIPPASNADRA,
BANGALORE, KARNATAKA.
PIN-560075.
2. / NAME OF INSTITUTION / M.S.RAMAIAH COLLEGE OF PHARMACY,
M.S.R.I.T. POST,
M.S.R. NAGAR,
BANGALORE-560054
3. / COURSE OF THE STUDY AND SUBJECT / M.PHARM
PHARMACEUTICAL CHEMISTRY
4. / DATE OF ADMISSION / 20TH JUNE 2009
5. /
TITLE OF THE TOPIC
SYNTHESIS AND PHARMACOLOGICAL EVALUATION OF
SOME NOVEL BENZOTRIAZOLE DERIVATIVES CONTAINING PYRAZOLIDINEDIONE MOIETIES

6. BRIEF RESUME OF THE INTENDED WORK

6.1 NEED FOR THE STUDY

Willow bark (Salix alba) had been used for many centuries. Salicylic acid was prepared by hydrolysis of bitter glycoside obtained from this plant. Sodium salicylate was used for fever and pain in 1875; its success led to the introduction of aspirin in 1899. The next major advance was the development of phenyl butazone in 1949 having anti-inflammatory activity almost comparable to corticosteroids. The term Nonsteroidal Anti-inflammatory drugs were coined to designate to these drugs.

Anti-inflammatory drugs modify inflammatory responses to diseases, but are not curative and do not remove the underlying cause of the disease. An ideal anti-inflammatory drug should affect only aberrant, uncontrolled inflammation and not interfere with the normal inflammatory response, which is a part of the body’s vital defense mechanism and other environmental factors.1

Benzotriazoles constitute important class of heterocyclic compounds with wide spectrum of activity. In recent years benzotriazole derivatives have received significant attention for their diverse range of antibacterial, antifungal, anti-proliferative, anti-tubercular, anti-inflammatory, anti-convulsant, antiviral activities.5,16,17,18,19,20,50,51-55,66

Pyrazolidinedione moiety has been found to possess antibacterial, anti-hypertensive, diuretic, analgesic, and anti-cancer properties.56,57,58,60

Structural modification of lead compounds is a major line of approach to new drug development.2 Synthesis and evaluation of pharmacological activities of novel heterocyclic compounds incorporating benzotriazole with pyrazolidinedione moiety will be done to obtain better anti-inflammatory activity66, analgesic activities18,66, antifungal17 and antibacterial activities18.

REVIEW OF LITERATURE

Ø  Brief history of different chemotherapeutic agents was discussed.1

Ø  The new drug development based on structural modification of lead compounds was discussed.2

Ø  Kinetic investigation of diazotization reaction in benzotriazole with dead-stop-end-point method was reported .3

Ø  N-Substituted benzotriazoles : Properties, Reactivities, Synthetic utility were discussed.4

Ø  Synthesis of some 2-(substituted)-5-[(N-benzotriazolomethyl)-1,3,4-thiadiazoyl]-4-thiazolidinones for their anti-fungal activity were reported.5

Ø  Copper-free ‘click’: 1,3-dipolar cylcoaddition of azides and arynes were reported .6

Ø  Benzotriazoles, benzotriazines and quinoxalines with sulfone functional group (I): (benzotriazol-1-yl)alkyl arenesulfones were reported.7

Ø  A smooth access to benzotriazoles via azide-benzyne cycloaddition were reported.8

Ø  Highly regioselective N-alkylation of benzotriazole under solvent free conditions was reported.9

Ø  Water tolerant unstabilised carbanion equilvalents: Bismuth(III) chloride-aluminum promoted alkylation’s of immonium cations to amines in aqueous media were reported .10

Ø  Electron-deficient benzotriazoles for the selective N-acetylation of nucleosides were reported .11

Ø  Microwave assisted green guanylations was reported.12

Ø  Enantioselective ethylation of N-(amidobenzyl)benzotriazoles catalysed by chiral aminoalcohols were reported .13

Ø  Benzotriazolophanes-New class of novel cyclophanes were reported.14

Ø  Synthesis of heteroaryl-benzotriazoles by Mannich condensations were reported.15

Ø  Microwave assisted synthesis and antifungal evaluation of Schiff bases of benzotriazolyl-4-amino-1,2,4 triazoles were reported.16

Ø  Synthesis of some new 5-[2-{(1,2,3-benzotriazole)-1-yl-methyl}-1´-(4´substituted aryl-3´-chloro-2´-oxo azetidine)]-amino-1,3,4-thiadiazoles: antifungal and antibacterial agents were reported.17

Ø  Synthesis of 5-arylidene-2-aryl-3-(benzotriazloacetamidyl)-1,3-thiazololidin-4-ones as analgesic and antimicrobial agents were reported.18

Ø  Fundamental structure-activity relationships associated with a new structural class of respiratory syncytial virus inhibitor was reported.19

Ø  Synthesis and biological evaluation of 2,5 di-substituted 1,3,4 oxadiazoles were reported.20

Ø  Synthesis of aminomethyl arylsulfides via novel synthetic auxiliary benzotriazole promoted by samarium diiode was reported.21

Ø  A new synthetic method for N-substituted selenoamides were reported.22

Ø  Synthesis of new benzotriazole derivatives were reported.23

Ø  Novel metallation of benzotriazoles and its utility in the synthesis of 4- substituted oxindoles were reported.24

Ø  Synthesis of original thiazoloindolo [3,2-c]quinoline and novel 8-N-substituted-11H-indolo[3,2-c] quinoline derivatives from benzotriazoles. Part I were reported.25

Ø  A convenient synthesis of functionalized N-(ethynyl)benzotriazoles were reported.26

Ø  Synthesis of vincinal diamines by SmI2-promoted reduction of N-(N´,N´-dialkylaminoalkyl) benzotriazoles were reported.27

Ø  Preparation of various enantiomerically pure (benzotriazole-1-yl)-and (benzotriazo-2-yl)-alkan-2-ols were reported.28

Ø  Samarium diiode promoted formation of 1,2-diketones and 1-acylamido-2-substituted benzimidazoles from N-acylbenzotriazoles were reported.29

Ø  Preparation of resin-bound alkynyl iodonium salts and their application in organic synthesis as alkynyl transfer reagents were discussed.30

Ø  Alkynylbenzotriazoles by direct alkylation of benzotriazole using alkynyliodonium Salts were reported.31

Ø  Elimination of benzotriazolyl group in N-(α-benzotriazol-yl-1-alkyl)amides and N-(α-benzotriazol-yl-1-alkyl)sulfonamides: Their self-coupling and cross coupling reactions with carbonyl compounds were reported.32

Ø  Sulfonyl derivatives of benzotriazole: Part 1. A novel approach to the activation of carboxylic acids were reported.33

Ø  Synthesis of 5,6-dihydro-4H-pyrido[3,2,1-jk]carbazoles via intermolecular [4+2] cycloaddition were reported.34

Ø  1,2,4-Triazolo[1,2-a]benzotriazoles: First examples of a novel ring system were reported.35

Ø  A novel Mannich-type reaction: Lanthanide triflate-catalyzed reactions of N-(α-aminoalkyl)benzotriazoles with silyl enolates were discussed.36

Ø  Cyclization reactions of α-amino radicals derived from N-(N´,N´-dialkylaminoalkenyl)benzotriazoles and samrium diiode were reported.37

Ø  The chemistry of N-Substituted benzotriazoles: A novel route to dienamines were discussed.38

Ø  Benzotriazole mediated synthesis of α-fluoro-β-amino esters were reported.39

Ø  Synthesis and structure of azol-1-yl derivatives of nitronyl and imino nitroxides were reported.40

Ø  N-(α-Amidoalkyl)benzotriazole-mediated synthesis of β´-amido β-diketones: a general synthetic protocol for N-[β-(3,5-di and 1,3,5-trisubstituted pyrazol-4yl)alkyl] amides were reported.41

Ø  Reductive cyclization of O-nitrophenylazobenzenes to 2-aryl-2-H-benzotriazoles by SmI2 were reported.42

Ø  Synthesis, structure, and isomerism of N-2,4-dinitophenylbenzotriazoles were reported.43

Ø  2-Aryl-2H-benzotriazole derivatives syntheses via constant current cathodic electrolysis reaction were reported.44

Ø  Manganese (III)-based oxidation of 1, 2-disubstituted pyrazolidione-3,5-diones in the presence of alkenes were reported. 45

Ø  Acylimine mediated N-N bond cleavage of pyrazolidinediones and subsequent conversion to dihydropyrimidinediones and malonamides were reported. 46

Ø  Expanding on the purification methodology of polyethylene glycol (PEG) Bound Molecules: The synthesis of 3, 5-pyrazolidinediones were reported. 47

Ø  Formation of 3-pyrazoline-5-thione disulfides from 3,5-pyrazolidinediones. C-alkylation of 1,5-pyrazolidinediones were reported. 48

Ø  Chemical electrochemical mechanism. Electrochemical reduction of some pyrazolidine-3, 5 diones in DMSO. Relation between voltammetric behavior and H nuclear magnetic resonance spectra was reported.49

Ø  Synthesis and antimycobacterial activity of selected nitrobenzyloxylated benzotriazoles were reported. 50

Ø  Synthesis of α-amino amides via α-amino imidoylbenzotriazoles were reported.51

Ø  Synthesis and characterization of some alkoxyphthalimide derivatives of benzotriazoylthiadiazoles and benzotriazolylthiazolidinones were reported. 52

Ø  Synthesis of new amino-1, 5-benzodiazapine and benzotriazole derivatives from dimedone were reported. 53

Ø  Toxicity of benzotriazole and benzotriazole derivatives to three aquatic species were reported. 54

Ø  Synthesis, characterization and antimicrobial activity of metal chelates of 5-[1(H)-benzotriazole methylene]-8-quinolinol were reported.55

Ø  Small molecule antagonists of the MDM2 oncoprotein as anticancer Agents were reported.56

Ø  Synthesis and antimicrobial evaluation of new isoxazole and pyrazole derivatives were reported.57

Ø  Aminomethinylierung H-aktiver verbindungen in der reihe analgestscher wirkstoffe was reported.58

Ø  Synthesis of 4,4-bis(2-hydroperoxyalkyl)pyrazolidine-3,5-diones using manganese(III)-catalyzed autoxidation were reported.59

Ø  Synthesis of some new indole derivatives of possible antimicrobial activity were reported.60

Ø  Process for the preparation of bromo-functionalized benzotriazole uv absorbers were reported.61

Ø  Benzotriazole mixtures, processes for producing them, and their use as metal passivators were reported.62

Ø  Synthesis and biological evaluation of aromatic benzotriazole amides were reported.63

Ø  Synthesis and antifungal activity of azetidinones were reported.64

Ø  Synthesis of 1-[3-(2-methyl-5-nitro-1H-imidazol-1-yl)propyl]-1H-1,2,3-benzotriazole and 1-[3-(2-methyl-5-nitro-1H-imidazol-1-yl)butyl]-1H-1,2,3-benzotriazole were reported.65

Ø  Synthesis of some novel triazole derivatives as anti-nociceptive and anti-inflammatory agents were reported.66

Ø  Synthesis and pharmacological evaluation of new pyrazolidine-3,5-diones as AT1 angiotensin II receptor antagonists were reported.67

Ø  Synthesis of new salicylamide derivatives with evaluation of their anti-inflammatory, analgesic and antipyretic activities were reported.68

Ø  Anticonvulsant activity of 1-alkyl-4-substituted 3,5-pyrazolidinediones were reported.69

Ø  Pyrazolidine-3,5-diones and 5-hydroxy-1H-pyrazol-3(2H)-ones, Inhibitors of UDP-N-acetlenolpyruvyl glucosamine reductase were reported.70

Ø  Pyrazolidine-3,5-dione derivatives as potent non-steroidal agonists of farnesoid X receptor: Virtual screening, synthesis, and biological evaluation were reported.71

Ø  Syntheisis studies on the synthesis of some new fused heterocylic compounds derived from 3,5-pyrazolidinedione was reported.72

6.3 OBJECTIVES OF STUDY

1)  To synthesize the proposed derivatives with optimum yield.

2)  To purify the synthesized compounds.

3)  To characterize the synthesized compounds by Spectral interpretation and by means of chemical tests.

4)  To evaluate the antimicrobial19, analgesic18,66 and anti-inflammatory66 activity of the synthesized compounds.

7. MATERIAL AND METHODS

7.1 SOURCE OF DATA

1)  Chemical abstracts, Tetrahedron, websites.

2)  Journals and publications.

3)  Lab based studies.

7.2 METHODS OF COLLECTION OF DATA

PRE-LABORATORY AND LABORATORY WORK

1)  PRE-LABORATORY WORK

The chemicals & reagents required for the synthesis and evaluation of the proposed compounds will be procured from reputed chemical suppliers like Merck, Ranbaxy, Qualigens, Himedia, S.D Fine Chemicals, Spectrochem, etc.

2) LABORATORY WORK

A) SYNTHESIS

Conventional methods of synthesis as well as microwave assisted synthesis12,16,26,49 will be attempted. The completion of the reaction will be determined by TLC, IR. Advantages and feasibility of the methods will be analyzed.

B)  PURIFICATION AND PHYSICAL CONSTANTS

The synthesized compounds will be purified by different methods like Fractional

Crystallization, recrystallization, distillation and chromatographic methods. The purity will be ascertained by TLC, IR, NMR, Mass Spectroscopy.

The physical parameters like solubility in various solvents, melting point or boiling point, nature of the crystals, color and percentage of yield will be obtained after the purification by recrystallizing in a suitable solvent.

C)  CHARACTERIZATION

The synthesized compounds will be characterized by:

1. Chemical tests for important functional groups.

2. Study of spectral data.

D)  PHARMACOLOGICAL STUDIES

Antinflammatory activity will be performed by using carragenean induced paw edema method66 and Analgesic activity will be performed by Eddy’s hot plate method.18, 66

SCREENING OF ANTI-INFLAMMATORY ACTIVITY

Anti-inflammatory agents are agents which modulate the process of inflammation. Currently much interest has been paid in the search for molecules with anti-inflammatory activity, which may lead to the discovery of new therapeutic agents which suppress inflammation in diverse disease conditions and prevent the amplification of disease process.

This review will address the commonly used animal models for the evaluation of anti-inflammatory activity in laboratory practice, including the principle and procedure behind each model.

Acute toxicity study:

This involves estimation of the minimum lethal dose, all animal experiments will be conducted under the conditions of the animal scientific procedures. The experimental protocol approved by the animal care review committee. Determination of minimum lethal dose of the drug molecules will be followed as per OECD guidelines.

INVIVO:

Acute model:

Carrageenan-induced paw edema in rats:

Principle: This model is based on the principle of release of various inflammatory mediators by carrageenan.

Procedure: Albino rats of Wistar strain, weighing 170-200g, of either sex will be divided into ten groups of six animals each. The animals will be maintained under normal environmental conditions. They will be fed with standard feed and water ad libitum. Tween 80 suspension (0.5%, v/v) of test compounds will be administered intraperitoneally. The control group will be given only 0.5% (v/v) Tween 80(0.5ml) suspension. One group will be administered diclofenac sodium as standard, intraperitoneally. Thirty minutes after the administration of test compounds and diclofenac sodium, paw edema will be induced by injecting 0.1ml of carragenean suspension (1 %v/v in normal saline), into sub planatar region of the left hind paw of each rat after measuring the normal paw volume. Three hours after carragenean injection, the increase in paw volume will be measured with plethysmometer. The anti-inflammatory activity will be measured in terms of percentage inhibition The percent inhibition is calculated using the formula as follows.

% edema inhibition = [1- (Vt / Vc)] X 100

Vt and Vc are edema volume in the drug treated and control groups respectively.

The rats will be divided into 10 groups of six animals each as follows:

Route of administration is intra-peritoneal.

Group I (control group) : Vehicle

Group II (standard) : Diclofenac Sodium (50mg/kg)

Group III : Derivative I

Group IV : Derivative II

Group V : Derivative III

Group VI : Derivative IV

Group VII : Derivative V

Group VIII : Derivative VI

Group IX : Derivative VII

Group X : Derivative VIII

STATISTICAL ANALYSIS

Results will be presented as mean ± SEM. Statistical differences between the means of the various groups are evaluated using one-way analysis of variance (ANOVA) followed by Bonferroni t-test against control. Statistical analysis will be performed using wistat statistical software.

SCREENING OF ANALGESIC ACTIVITY

Analgesics are the agents used to reduce pain.

This will address the commonly used animal models for the evaluation of analgesic activity in laboratory practice along with principle and procedure involved in each animal model.

Analgesic Activity:

1.  Eddy’s hot plate method:

Here the pain threshold is considered to be reached when the animals lift/lick their paws, or jump.The hot plate is used to measure the response latencies.

Procedure: The animals will be placed on Eddy’s Hot Plate maintained at a temperature of 55°C±1°C. A cut off period of 15 sec, will be observed each time to avoid damage to the paws. Reaction time and the type of response viz. jumping, withdrawal of paws or the licking of the paws will be noted using a stopwatch. The latency will be recorded before and after 15, 30, 60 and 120 min of treatment.

Animals required:

Group I (control group) : Untreated

Group II (Standard) : Tramadol (30mg/kg)

Group III : Derivative I

Group IV : Derivative II

Group V : Derivative III

Group VI : Derivative IV

Group VII : Derivative V