We here in describe the molecular hybridisation attack, to synthesise fresh ring constrained parallels cinnamide derived functions 5a-5l as possible antiepileptic, antinociceptive and antioxidant activities. The designing of compounds involved in uniting the structural characteristics i.e. , morpholine, piperidinyl, piperazine and arylpiperazines with cinnamoyl pharmacophoric group. [ A series of pealing constrained parallels cinnamide derived functions was synthesized as possible antiepileptic, antinociceptive and antioxidant activities by uniting the cardinal pharmacophoric group. The piperazine mediety and other parallels, besides the certain characteristics of SB366791 were hybridized/ clubbed to obtain the rubric compounds. ] Of these, compound 5e with 4-flourophenyl permutation on piperazine ring exhibited highest activity in capsaicin induced theoretical account and anticonvulsant theoretical accounts.
Further, all the derived functions studied for molecular and preadmet belongingss.
Cinnamides have a long history of human usage possessing assortment of biological belongingss, such as anticancer, antidepressant, antimycobacterial, anticonvulsant and antinociceptive activities, etc [ 1-6 ] . A series of N-aryl trans cinnamides were reported as novel, potent and selective competitory inhibitor of human and rat TRPV1 and therefore expose antinociceptive activity ( AMG9810, SB-366791 ) [ 7-9 ] . The derived functions of m- ( trifloromethyl ) cinnamide and some ( E ) and ( Z ) N-alkyl-alpha, beta-dimethyl cinnamides were besides reported to possess anticonvulsant activity [ 10-12 ] . The past decennaries have demonstrated many efforts to place the structural characteristics of compounds important for anticonvulsant and antinociceptive activities. As a consequence it was proved that one of the of import nucleus fragments possessing N incorporating heterocyclic system attached to the other aromatic system via a carbonyl or methylenyl group. In position of the above probes, the present survey is focussed on synthesising different N incorporating heterocyclic systems like piperidine, morpholine, piperazine and N-arylpiperazines attached to the styryl carbonyl mediety antinociceptive and anticonvulsant activities.
[ 13, 14 ] .Epilepsy and neuropathic hurting are upsets characterised by either inappropriate self-generated neural activity or inordinate neural activity in response to physiological stimulations. These upsets are presently managed by drugs that are capable of stifling neural irritability [ 15 ] . Drugs normally used for epilepsy therapy include carbamazepine, Phenytoin, ethosuximide, lamotrigine, Neurontin, etc [ 16 ] . Of these, Neurontin and carbamazepine are approved for the intervention of neuropathic hurting and lamotrigine has demonstrated efficaciousness for neuropathic hurting in clinical tests [ 17 ] . Pharmacological and clinical surveies have documented the pathophysiological similarities in epilepsy and neuropathic hurting theoretical accounts.
Therefore, antiepileptic agents may hold good potency to pull off neuropathic hurting [ 18 ] . Due to the shared pathomechanism of many cardinal and peripheral nervous system upsets, several antiepileptic and antinociceptive drugs may hold efficaciousness to cut down the oxidative stress/ antioxidant therapy.Based on the importance of the cinnamides, piperazine and N-arylpiperazine pharmacophoric medieties for antiepileptic and antinociceptive activities, it is planned to unite these possible scaffolds in to a fresh intercrossed molecule. We have designed and synthesized a fresh series of cinnamide derived functions incorporating morpholinyl, piperidinyl, piperazinyl and N-arylpiperazinyl medieties as ring constrained parallels possessing promising biological activities.
Consequences and treatment
Synthesis of 1- ( 4-substitutedpiperazin-1-yl ) prop-2-ene-1-one derived functions was carried out by simple and executable processs ( scheme 1 ) .
Here, cinnamicacid was treated with thionylchloride, a versatile and extremely reactive chlorinating agent, which produced cinnamoyl chloride by the nucleophilic permutation of Cl. This farther reacted with secondary aminoalkanes like piperidine, morpholine, piperazine and substituted piperazines by dehydrohalogenation reaction affording the rubric compounds 3a-3l as depicted in strategy 1. The constructions of the compounds were confirmed by IR, 1HNMR, mass and elemental analysis. The IR spectra of the compounds showed a wide set in the scope of 1655-1640cm-1 conveyable to the C=O stretching in amide functional group and a set at 1640-1610 cm-1 bespeaking the C=C stretching in trans cinnamoyl group. The mass spectra of the compounds ( 5a-5l ) showed the molecular ion extremums and the elemental analysis for the compounds are within the bounds of A±0.
4 % of theoretical value.The 1H NMR spectrum of the compounds supported the constructions of 3a-3l. These compounds showed a doublet in the part of 6.35-7.
60 ppm due to alkenyl protons in cinnmoyl mediety ( J=12.0-15.8 Hz ) , a wide doublet or a three in the part of 2.1-2.
8 ppm and 3.2-3.9 ppm indicated the protons of the heterocycles like piperidinyl, morpholinyl and piperazinyl permutations. A multiplet in the part of 6.
5- 7.5 ppm indicated the aromatic protons present in the phenyl ring.Preclinical find and development of new drug campaigners for the rating of both antiepileptic and antinociceptive activities are based on the usage of animate being theoretical accounts. The profile of antinociceptive activity of the compounds 5a-5l was evaluated in capsaicin-induced and formol induced nociceptive methods after the unwritten disposal of the compounds to the male Swiss albino mices at the dosage of 10 mg/kg and observations were made after 1h. The consequences were shown in tabular arraies 2 & A ; 3, fig 3, 4 and 5. All the compounds 5a-5h, 5j and 5k exhibited the important activity in capsaicin induced nociception except 5i and 5l. Intensify 5e with 4-florophenyl permutation exhibited highest activity ( 73.
5 % ) , which may be due to the presence of negatron retreating p-floro permutation nowadays on phenyl piperazinyl mediety. whereas, compounds 5f and 5d possessing 4-chlorophenyl and phenyl permutations at the 4th place of piperazine besides showed promising activity ( 64.7 and 61.7 % ) . The isosteric replacing of N-phenyl ring in 5d with pyridin-2-yl and pyrimidin-2-yl as in 5h and 5i resulted in a drastic lessening in activity. Compounds 5j, 5k and 5l are structurally related to 5d, 5f and 5h severally with reduced antinociceptive activity.
This may be due to the presence of methylenedioxy group present on 3rd and 4th places of phenyl ring of cinnamoyl mediety.In formol induced nociception method, all compounds 5a-5l exhibited important activity. Isosteric replacing of morpholinyl mediety in 5b with piperazine as in 5c increased the activity, which may be due to the interaction of free NH with mark site. Presence of pheny ring at the 4th place of piperazine as in 5d decreased the activity, whereas 4-florophenyl as in 5e and 5k, and 4-chlorophenyl as in 5f exhibited good antinociceptive activity. The compounds are non comparable to tramadol in exhibiting the protection against formol induced nociception.The 2nd stage of formol induced nociception method indicates anti-inflammatory response.
Here, compounds 5b, 5c, 5e and 5k exhibited important activity. Out of these, compounds possessing morpholine ring showed good anti-inflammatory activity. Compound 5c possessing free piperazine ring besides showed good activity, followed by 4-fluorophenylpiperazinyl permutation. Other compounds did non exhibit important anti-inflammatory response.The antiepileptic profile of the compounds 5a-5l was evaluated by two methods, hypodermic pentylenetetrazole induced and maximum electroconvulsive therapy induced methods. All the compounds exhibited important protection except 5c and 5g against pentylenetetrazole induced ictuss.
Compounds possessing p-florophenyl permutation on piperazine ring as in 5f exhibited good latency periods and comparable to the standard drug, Valium. Comparison of the activity of the bioisosteric parallels as in 5a, 5b and 5c showed increased latency periods in the order of increased lipophilicity ( 5c & lt ; 5b & lt ; 5a ) . Compounds 5b, 5d and 5e exhibited maximal protection against mortality and are comparable to standard drug, Valium.In instance of maximum electroconvulsive therapy induced method, all the compounds 5a-5l showed important protection. Compounds possessing pyrimidin-2-yl permutation as in 5h displayed good protection against electroconvulsive therapy induced ictuss ( 100 % ) and is more powerful than the standard drug, diphenylhydantoin. Compounds with phenyl, 4-florophenyl and morpholinyl permutations as in 5d, 5e and 5b severally showed less limb extension periods and therefore marked ictus inhibitory activity and are comparable to the standard drug, Phenytoin.All the synthesized compounds were besides evaluated for in vitro antioxidant activity by three methods.
Compound 5i exhibited good scavenging activity ( IC50=7.4 Aµg ) against DPPH free groups and is more powerful than the standard ascorbic acid ( IC50=10.6 Aµg ) , which may be due to the N-pyrimidin-2-yl permutation. Table 6 shows the ability of the trial compounds to scavenge azotic oxide in the IC50 ranges from 6.9-40.2 Aµg.
Among these, compound possessing pyrimidin-2-yl permutation as in 5i exhibited highest activity ( IC50=6.9 Aµg ) and comparable to ascorbic acid ( IC50=7.1 Aµg ) . The compound holding 4-nitrophenyl permutation ( 5g ) showed the highest activity ( IC50=76 Aµg ) in ace oxide scavenging check, more active than ascorbic acid ( IC50=163.
5 Aµg ) .Drug-likeness is a qualitative construct, estimated from the molecular belongingss that affect their soaking up, distribution, metamorphosis and elimination ( ADME ) of a compound by utilizing Molinspiration package for the compounds under survey [ — ] . Some basic molecular forms such as divider coefficient ( log P ) , molecular weight ( MW ) , or H bond acceptors and givers in a molecule indicate membrane permeableness and bioavailability [ — ] . Number of rotatable bonds explains the conformational alterations and flexibleness of molecules and for the binding to the receptors. It is revealed that figure of rotatable bonds should be a‰¤10 to go through the unwritten bioavailability [ — ] . Compounds 5a-5l possesses 2-4 rotatable bonds and hence, exhibits the optimal conformational flexibleness.
Molecular polar surface country ( TPSA ) is a really utile parametric quantity to foretell the conveyance belongingss of drugs like enteric soaking up and blood-brain barrier traversing. TPSA and volume are reciprocally relative to the per centum of soaking up ( % ABS ) and calculated utilizing the equation: % ABS= 109 A± 0.345 A- TPSA, [ — ] . It was observed that all the rubric compounds exhibited a great % soaking up runing from 85 to 100 % ( table 5 ) . The Lipinski ‘s regulation of five provinces that most molecules with good membrane permeableness have logP a‰¤ 5, molecular weight a‰¤ 500, figure of H bond acceptors a‰¤ 10 and figure of H bond givers a‰¤ 5 and widely used as a filter for drug-likeness.
Furthermore, none of the compounds violated Lipinski ‘s parametric quantities, doing them potentially assuring agents for antiepileptic and antinociceptive therapy.The soaking up and distribution parametric quantities like unwritten bioavailability, in vitro plasma protein binding and blood-brain barrier incursion were calculated from preADME forecaster, a molecular form tool [ — ] . Oral drug soaking up can be predicted utilizing in vitro theoretical accounts like human enteric soaking up ( % HIA ) , Caco2 cell ( PCaco2 ) and MDCK cell ( PMDCK ) permeablenesss ( table 6 ) . As per the standard compounds of the series ( 5a-5l ) showed % HIA runing from 96-100 % , optimal Caco2 cell permeableness ( 4-70 nm/sec ) and compounds 5a-5e and 5l displayed optimal MDCK cell permeableness ( 25-500 nm/sec ) . Compounds 5a-5f and 5l showed optimal incursion into CNS via the blood-brain barrier.
The present survey revealed that compound 5e showed promising antiepileptic and antinociceptive activities. The presence of 4-florophenyl permutation on piperazine ring may be responsible //desirable characteristic to demo the antiepileptic and antinociceptive consequence.
Molecular belongingss anticipation informations support that, the compounds being as drug-likeness.
Aldehydes and esters were procured from Sigma-Aldrich and Merck chemicals. All other chemicals are of AR class. Purity of the samples was monitored by TLC analysis utilizing Precoated aluminum home bases ( Merck ) , coated with Silica Gel ( Kieselgel 60 ) with F254 index.
Melting points were determined in unfastened capillaries utilizing Analab runing point setup and were uncorrected. IR spectra were recorded as KBr pellets on a Jasco FTIR ( FTIR-4100 ) Spectrophotometer. 1H NMR spectra were carried out on Jeol-400 MHz NMR Spectrophotometer ( JNM-400 ) utilizing TMS as internal mention.
Chemical displacements ( I? values are given in parts per million ( ppm ) utilizing CDCl3 as solvent matching invariables ( J ) in Hz. Dividing forms are designated as follows: s, vest ; vitamin D, doublet ; t, three ; q, four ; m, multiplet.Accurate multitudes were obtained on LCMS ( schimadzu ) APCI modelLC-2010 EV. Elemental analyses were performed on Perkin Elmer 2400 C, H, N elemental analyser.
General method for the synthesis of compounds 5a-5l
To 0.01 mol of compound 3 or 4 dissolved in propanone, 0.01mol of different secondary aminoalkanes and 2-3 beads of triethylamine were added at room temperature and continuously stirred for 10 -12h to obtain the compounds 5a-5l. Completion of the reaction was monitored by TLC home bases.
synthesis of methylenedioxycinnamic acid ( 2 )
A mixture of piperonal ( 0.165 mol ) , malonic acid ( 0.36 mol ) , dry pyridine ( 75ml ) and piperidine ( 1.5 milliliter ) is refluxed for one hr ( a rapid development of carbondioxide takes topographic point ) . The cooled reaction mixture was poured into H2O incorporating adequate hydrochloric acid to fade out pyridine.
The precipitated acid was filtered and washed with H2O to obtain compound 2 ( 88 % output ) .
synthesis of cinnamoyl chloride ( 3 ) or methylenedioxycinnamoyl chloride ( 4 ) .
0.01mol of cinnamicacid ( 1, 1.66g ) or compound ( 2, 2.1g ) dissolved in methylene chloride, 0.01mol of thionylchloride was added at room temperature and allowed for stirring for 5 h. After the completion of reaction, surplus of thionylchloride was removed by distillment to obtain the compound 3 or 4.
These compounds were used without farther purification for following measure.
PHYSICAL AND SPECTRAL DATA OF THE COMPOUNDS
synthesis of the ( E ) -3-phenyl-1- ( piperidin-1-yl ) prop-2-en-1-one // ( E ) -3-phenyl-1- ( piperidin-1-yl ) propenal ( 5a ) : 1.66g of cinnamoylchloride ( 3, 0.01mol ) was dissolved in propanone, 1ml of ( 0.01 mol ) piperidine and 2-3 beads of triethylamine was added at room temperature with uninterrupted stirring for 10 -12h to obtain the compound 5a as white coloring material pulverization with 58 % output. M.
p. 143A°C. I»max 285 nanometers, Rf: 0.
225. IR ( KBr ) I?max, cm-1: 3095, 3080 & A ; 3060 ( Ar C-H str ) , 3029 ( trans =CH str ) , 1652 ( amide C=O str ) , 1631 ( trans C=C str ) . 1H NMR ( 400MHz, CHCl3 ) I? ( ppm ) : 2.45-2.55 ( dt, 6H, J=4.7 Hz, 3CH2 of piperidine ) , 3.4 ( T, 4H, J=5.
2 Hz 2CH2 of piperidine ) , 6.35-6.45 ( vitamin D, 1H, J=15.6 Hz, -CH=CH- of cinnamoyl group ) , 7.35-7.45 ( vitamin D, 1H, J=15.67Hz, -CH=CH- of cinnamoyl group ) .
APCI-MS: m/z = 215.9 ( M ) + , 217.9 ( M+2H ) + .synthesis of the ( E ) -1-morpholino-3-phenylprop-2-en-1-one // ( E ) -1-morpholino-3-phenyl-acrplein ( 5b ) : 1.66g of compound 3 was dissolved in propanone, 1ml of ( 0.01mol ) morpholine and proceeded as in 5a obtain the compound 5b as white crystalline pulverization, give 57 % . m.p 148A°C.
I»max 275 nanometer. Releasing factor: 0.28, IR ( KBr ) I?max, cm-1: 3075 & A ; 3056 ( Ar C-H str ) , 3012 ( trans =CH str ) , 2987 ( C-H str ) , 1652 ( amide C=O str ) , 1631 ( trans C=C str ) . 1H NMR ( 400MHz, CHCl3 ) I? ( ppm ) : 2.45-2.
55 ( dt, 6H, J=5.2Hz, 2CH2 of morpholine ) , 3.4 ( T, 4H, J=5.2 Hz 2CH2 of morpholine ) , 6.35-6.45 ( vitamin D, 1H, J=14.8 Hz, -CH=CH- of cinnamoyl group ) , 7.35-7.
45 ( vitamin D, 1H, J=14.8 Hz, -CH=CH- of cinnamoyl group ) . APCI-MS: m/z = 216.9 ( M ) + , 218.9 ( M+2H ) + .synthesis of the ( E ) -3-phenyl-1- ( piperazin-1-yl ) prop-2-en-1-one // ( E ) -3-phenyl-1- ( piperazinyl ) propenal ( 5c ) : 1.86g of ( 0.
01mol ) N-boc-piperazine and proceeded as in 5a. The obtained compound was subjected for the deprotection and produced the compound 5c as white crystalline pulverization, give 62 % . m.
p 180A°C. I»max 282nm. Releasing factor: 0.235. IR ( KBr ) I?max, cm-1: 3095 & A ; 3060 ( Ar C-H str ) , 3029 ( trans =CH str ) , 1638 ( amide C=O str ) , 1599 ( Ar C-C str ) . 1H NMR ( 400MHz, CHCl3 ) I? ( ppm ) : 2.
30-2.45 ( br vitamin D, 4H, J=4.2 Hz, 2CH2 of Piperazine, 3.
4-3.6 ( br T, 4H, J=4.2Hz, 2CH2 of Piperazine ) , 6.0 ( Br s, 1H, NH of piperazine ) , 6.5 ( vitamin D, 1H, J=12.5 Hz, -CH=CH-C6H5 ) , 7.12-7.
35 ( m, 5H, Ar-H ) , 7.6 ( vitamin D, 1H, J=12.5 Hz, -CH=CH-C6H5 ) . APCI-MS: m/z = 216.
9 ( M ) + , 217.9 ( M+H ) + .synthesis of the ( E ) -3-phenyl-1- ( 4-phenylpiperazin-1-yl ) prop-2-en-1-one ( 5d ) : 1.62g of ( 0.01mol ) N-phenylpiperazine and proceeded as in 5a to obtain the compound 5d as glistening white crystalline flakes, yield 78 % . M.
p. 146A°C. I»max 276.3 nanometer. Releasing factor: 0.29. IR ( KBr ) I?max, cm-1: 3098 & A ; 3063 ( Ar C-H str ) , 3027 ( trans =CH str ) , 1638 ( amide, C=O str ) .
1H NMR ( 400MHz, CHCl3 ) I? ( ppm ) : 3.28-3.36 ( br vitamin D, 8H, 4CH2 of piperazine ) , 6.79 ( vitamin D, 1H, J=15.8 Hz, -CH=CH-C6H5 ) , 6.89-7.49 ( m, 10H, Ar-H ) , 7.51-7.
55 ( vitamin D, 1H, J=15.8 Hz, -CH=CH-C6H5 ) . APCI-MS: m/z = 292.9 ( M ) + .synthesis of the ( E ) -1- ( 4- ( 4-fluorophenyl ) piperazin-1-yl ) -3-phenylprop-2-en-1-one ( 5e ) : 1.82g of ( 0.01mol ) N- ( 4-florophenyl ) -piperazine and proceeded as in 5a to obtain the compound 5e. It was obtained as white silky pulverization, give 72 % .
M.p. 142A°C. I»max 325 nanometers, Rf: 0.215, IR ( KBr ) I?max, cm-1: 3097 & A ; 3070 ( Ar C-H str ) , 3024 ( trans =C-H str ) , 2994,2950 & A ; 2893 ( alkyl CH2 C-H str ) , 1641 ( amide C=O str ) . 1H NMR ( 400MHz, CHCl3 ) I? ( ppm ) : 3.
28-3.40 ( br vitamin D, 8H, 4CH2 of piperazine ) , 6.35-6.45 ( Doctor of Divinity, 1H, J=13.8HZ, -CH=CH-C6H5 ) , 6.5-7.65 ( m, 9H, J=7.
29Hz, J=8.1Hz Ar-H ) , 7.3-7.4 ( Doctor of Divinity, 1H, J=13.8HZ, -CH=CH-C6H5 ) . APCI-MS: m/z = 310.9 ( M ) + , 292.
1 ( C19H19N2O ) + .synthesis of the ( E ) -1- ( 4- ( 4-chlorophenyl ) piperazin-1-yl ) -3-phenylprop-2-en-1-one ( 5f ) : 1.96g of ( 0.
01mol ) N- ( 4-chlorophenyl ) -piperazine and proceeded as in 5a to obtain the compound 5f. It was obtained as white silky crystals, yield 71 % .. M.p. 155A°C, I»max 277 nanometer, Rf: 0.25.
IR ( KBr ) I?max, cm-1: 3091 & A ; 3057 ( Ar C-H str ) , 3024 ( trans =C-H str ) , 2984 & A ; 2943 ( alkyl CH2 C-H str ) , 1641 ( amide C=O str ) . 1H NMR ( 400MHz, CHCl3 ) I? ( ppm ) : 3.28-3.
40 ( br vitamin D, 8H, 4CH2 of piperazine ) , 6.25-6.35 ( Doctor of Divinity, 1H, J=12.2 Hz, -CH=CH-C6H5 ) , 6.45-7.45 ( m, 9H, Ar-H ) , 7.
35-7.45 ( Doctor of Divinity, 1H, J=12.2Hz, -CH=CH-C6H5 ) . APCI-MS: m/z = 326.9 ( M+H ) + .synthesis of the ( E ) -1- ( 4- ( 4-nitrophenyl ) piperazin-1-yl ) -3-phenylprop-2-en-1-one ( 5g ) : 2.07g of ( 0.
01mol ) N- ( 4-nitrophenyl ) -piperazine was used to obtain the compound 5g and appeared as pale xanthous coloring material, give 67 % . M.p. 175A°C, I»max 407 nanometer, Rf: 0.
25. IR ( KBr ) I?max, cm-1: 3086 ( Ar C-H str ) , 3020 ( trans =C-H str ) , 2989 & A ; 2933 ( alkyl CH2 C-H str ) , 1645 ( amide C=O str ) . 1H NMR ( 400MHz, CHCl3 ) I? ( ppm ) : 3.
25-3.40 ( br vitamin D, 8H, 4CH2 of piperazine ) , 6.20-6.
35 ( Doctor of Divinity, 1H, J=12.5 Hz, -CH=CH-C6H5 ) , 6.45-7.45 ( m, 9H, Ar-H ) , 7.35-7.
45 ( Doctor of Divinity, 1H, J=12.5Hz, -CH=CH-C6H5 ) . APCI-MS: m/z = 337.1 ( M ) + .synthesis of the ( E ) -3-phenyl-1- ( 4- ( pyridin-2-yl ) piperazin-1-yl ) prop-2-en-1-one ( 5h ) : 1.63g of ( 0.
01mol ) N- ( pyridin-2-yl ) -piperazine was used to obtain the compound 5h appaered as white crystals, yield 64 % . M.p. 125A°C.
I»max 290 nanometers, Rf: 0.275. IR ( KBr ) I?max, cm-1: 3094 & A ; 3076 ( Ar C-H str ) , 1625 ( amide C=O str ) . 1H NMR ( 400MHz, CHCl3 ) I? ( ppm ) : 2.
15-2.25 ( T, 4H, J=4.2 Hz, 2CH2 of piperazine ) , 3.8-3.9 ( T, 4H, J=4.2 Hz, 2CH2 of piperazine ) , 6.35-6.45 ( vitamin D, 1H, J=14.
5 Hz, -CH=CH-C6H5 ) , 6.9-8.1 ( m, 9H, J=7.35Hz, J=7.9 Hz, Ar-H ) , 7.6-7.7 ( vitamin D, 1H, J=14.5 Hz, -CH=CH-C6H5 ) .
APCI-MS: m/z = 292.9 ( M ) + , 214.9 ( M+2H ) + .synthesis of the ( E ) -3-phenyl-1- ( 4- ( pyrimidin-2-yl ) piperazin-1-yl ) prop-2-en-1-one ( 5i ) : 1.
64g of ( 0.01mol ) N- ( pyrimidin-2-yl ) -piperazine used in the 5a process to obtain the compound 5i as dull White coloring material crystals, yield 68 % . M.p. 140A°C. I»max 401 nanometers, Rf: 0.
28. IR ( KBr ) I?max, cm-1: 3079 & A ; 3072 ( Ar C-H str ) , 2926 ( C-H str, CH2 ) , 1625 ( amide C=O str ) . 1H NMR ( 400MHz, CHCl3 ) I? ( ppm ) : 2.15-2.25 ( T, 4H, J=4.5 Hz, 2CH2 of piperazine ) , 3.8-3.9 ( T, 4H, J=4.
5 Hz, 2CH2 of piperazine ) , 6.35-6.45 ( vitamin D, 1H, J=14.2 Hz, -CH=CH-C6H5 ) , 6.8-8.1 ( m, 9H, Ar-H ) , 7.6-7.
7 ( vitamin D, 1H, J=14.2 Hz, -CH=CH-C6H5 ) . APCI-MS: m/z = 293.9 ( M ) + .synthesis of the ( E ) -3- ( benzo [ vitamin D ] [ 1,3 ] dioxol-6-yl ) -1- ( 4-phenyl ) piperazin-1-yl ) prop-2-en-1-one ( 5j ) : 2.
1g of ( 0.01mol ) compound 4 was dissolved in propanone, 1.62g of ( 0.01mol ) N- ( phenyl ) -piperazine and 2-3 beads of triethylamine was added at room temperature with uninterrupted stirring for 10 -12h to obtain the compound 5j and appeared as white pulverization with 66 % output. M.p.
252A°C. I»max 322 nanometers, Rf: 0.235.
IR ( KBr ) I?max, cm-1: 3098 & A ; 3075 ( Ar C-H str ) , 1638 ( amide C=O str ) . 1H NMR ( 400MHz, CHCl3 ) I? ( ppm ) : 3.1-3.
3 ( br vitamin D, 4H, J=5.7Hz, 2CH2 of piperazine ) , 3.75-3.90 ( br vitamin D, 4H, J=5.7Hz, 2CH2 of piperazine ) , 5.
85 ( s, 2H, CH2 of -OCH2-O ) , 6.35-6.45 ( vitamin D, 1H, J=15.8Hz, CH general practitioner of -CH=CH-C6H5 ) , 7.
55-7.65 ( vitamin D, 1H, J=15.8Hz, CH general practitioner of -CH=CH-C6H5 ) , 6.85-7.45 ( m, 8H, Ar-H ) .
APCI-MS: m/z = 335.9 ( M ) + , 215.0 ( C13H15N2O ) + .synthesis of the ( E ) -3- ( benzo [ vitamin D ] [ 1, 3 ] dioxol-6-yl ) -1- ( 4- ( 4-fluorophenyl ) piperazin-1-yl ) prop-2-en-1-one ( 5k ) : 1.
82g of ( 0.01mol ) N- ( 4-florophenyl ) -piperazine used and proceeded as in 5j to obtain the compound 5k as white pulverization with 60 % output. M.p. 250A°C. I»max 315 nanometers, Rf: 0.24.
IR ( KBr ) I?max, cm-1: 3058 ( Ar C-H str ) , 2964 ( C-H str in CH2 ) , 1638 ( amide C=O str ) . 1H NMR ( 400MHz, CHCl3 ) I? ( ppm ) : 3.1-3.2 ( T, 4H, J=4.
2Hz, 2CH2 of piperazine ) , 3.65-3.80 ( br vitamin D, 4H, J=4.9Hz, 2CH2 of piperazine ) 5.9 ( s, 2H, CH2 of -OCH2-O ) , 6.
65-6.75 ( Doctor of Divinity, 1H, J=15.3Hz, CH of -CH=CH-C6H5 ) , 7.55-7.70 ( vitamin D, 1H, J=15.3Hz, CH of -CH=CH-C6H5 ) , 7.05-7.
45 ( m, 7H, Ar-H ) . APCI-MS: m/z = 354.9 ( M+H ) + .synthesis of the ( E ) -3- ( benzo [ vitamin D ] [ 1,3 ] dioxol-6-yl ) -1- ( 4- ( pyridin-2-yl ) piperazin-1-yl ) prop-2-en-1-one ( 5l ) : 1.63g of ( 0.
01mol ) N- ( pyridin-2-yl ) -piperazine used in 5j process to obtain the compound 5l. It was obtained as white pulverization with 60 % output. M.p.
249A°C. I»max 317 nanometers, Rf:0.255. IR ( KBr ) I?max, cm-1: 3064 ( Ar C-H str ) , 2973 ( C-H str, CH2 ) , 1625 ( amide C=O str ) . 1H NMR ( 400MHz, CHCl3 ) I? ( ppm ) : 2.
15-2.25 ( T, 4H, J=4.2 Hz, 2CH2 of piperazine ) , 3.8-3.9 ( T, 4H, J=4.
2 Hz, 2CH2 of piperazine ) , 6.35-6.45 ( vitamin D, 1H, J=14.5 Hz, -CH=CH-C6H5 ) , 6.9-8.1 ( m, 9H, J=7.
35Hz, J=7.9 Hz, Ar-H ) , 7.6-7.7 ( vitamin D, 1H, J=14.
5 Hz, -CH=CH-C6H5 ) . APCI-MS: m/z = 336.9 ( M ) + .
Male Swiss Albino mices ( 18-22g ) and Male wistar rats ( 150-200g ) were used as experimental animate beings and were obtained from King Institute Of Preventive Medicine, Guindy, Chennai-32.
The animate beings were maintained in well-ventilated room by keeping the temperature 23A±2A°C with natural 12A±1 h day-night rhythm in the polypropene coops. They were fed ad libitum with balanced rodent pellet diet and H2O throughout the experimental period. The animate beings were sheltered for one hebdomad and prior to the experiment they were acclimatized to laboratory temperature.
The protocol was approved by Institutional Animal Ethics Committee constituted for the intent as per CPSCEA guidelines ( 1220/a/08/CPCSEA/ANCP/06 ) .
Acute toxicity survey:
The survey was conducted as per OECD-425 usher lines for proving of chemicals acute unwritten toxicity [ 22 ] and used to repair the safe dosage for the compounds 5a-5l. Swiss albino mice were divided into 14 groups each incorporating 5 animate beings. Drugs were administered by unwritten path in different concentrations ( 2000, 1000, 500, 250, 100, 50, 20 and 10mg/kg organic structure weight ) . The animate beings were observed for their decease over a period of 7days. The LD50 values were calculated by up and down method and dosage was fixed as 10mg/kg organic structure weight.
Evaluation of Anticonvulsant Activity
The Hypodermic Pentylenetetrazole Seizure trial ( Sc PTZ )
This method utilizes a dosage of Pentylenetetrazole ( PTZ ) 80mg/kg in rats that produces clonic ictuss. The Male wistar rats were divided into 14 groups of six rats each.
Group 1 was the control group received vehicle ; Group 2 received 5 mg/kg organic structure weight of Diazepam, Group 3 -14 received the 10mg/kg organic structure weight of compounds 5a-5l severally, which were prepared by suspended in 0.5 % sodiumcarboxymethylcellulose. All the drugs were administered 1h anterior to the PTZ disposal and the latency period of the ictuss and the mortality were observed [ — – ] .
The Maximal Electric Shock trial ( MES )
The anticonvulsant belongings of the drug in this theoretical account was assessed by its ability to protect against Maximal Electric Shock induced paroxysms. Male Wistar albino rats were divided into 14 groups of six rats each. Group 1 was the control group received vehicle ; Group 2 received 30 mg/kg organic structure weight of Phenytoin, Group 3 -14 received the trial compounds 5a-5l severally. Maximal Electric Shock of 150mA current for 0.
2 sec was applied through corneal electrodes to bring on paroxysms in the control, standard and test compounds treated animate beings [ — – ] .
Evaluation of antinociceptive activity:
Method for Capsaicin-induced nociception:
Male Swiss mice ( 18-22g ) were used for the method and followed the version to the experimental conditions. 20Aµl of capsaicin ( 1nmol/paw ) was injected subplantarly in to the right hind paw, and the entire figure of flinchings of the injected paw was measured separately for 5 min and used as a measuring of nociception. The animate beings were treated with control and trial compounds 5a-5l utilizing unwritten forced feedings ( 10mg/kg ) 1 H prior to capsaicin injection [ — – ] .
Method for formalin-induced nociception:
The mice were divided in to fourteen groups each incorporating six animate beings. Group 1 was the control group received vehicle ; Group 2 received tramadol injection ( 5mg/ kilogram, s.
c. ) , Group 3 -14 received the trial compounds 5a-5l ( 10mg/kg, p.o ) severally, 1h prior to the formol injection. Animals were injected intraplantarly with 20 I?l of 2.5 % formalin solution ( 0.92 % of methanal, made up in saline solution 137 millimeter NaCl ) . Mice were instantly placed in a glass cylinder 20 centimeter in diameter and observed from 0 to 30 min following formalin injection.
The sum of clip spent creaming the injected paw was timed with a chronometer and was considered as declarative mood of nociception. The first stage of the nociceptive response usually peaked 5 min after the formol injection and the 2nd stage 15 to 30 min after the formol injection, stand foring the neurogenic and inflammatory nociceptive responses, severally.
Evaluation of antioxidant activity:
DPPH extremist scavenging check:
The ability to scavenge 2, 2-diphenyl-1-Picryl-Hydrazyl ( DPPH ) group was determined by utilizing DPPH method is as follows.
1 milliliter of trial compound ( 5a-5i ) ( 10, 50, 100, 250, 500 Aµg/ml ) in ethyl alcohol and the reaction mixture was added to 4 milliliter of 0.004 % methanol solution of DPPH and incubated in a dark topographic point for 30 min. The optical density of the samples was read at 517 nanometer. Ascorbic acid was used as mention criterion. Percentage suppression of DPPH free group by the sample was calculated [ — – ] .
Measurement of azotic oxide activity:
The process is based on the rule that, sodiumnitroprusside in aqueous solution at physiological pH spontaneously generates azotic oxide which interacts with O to bring forth nitrite ions that can be estimated utilizing Griess reagent. Scavengers of azotic oxide compete with O, taking to reduced production of nitrite ions.
For the experiment, sodiumnitroprusside ( 10 millimeter ) , in phosphate-buffered saline, was assorted with different concentrations of the trial compounds 5a-5i, dissolved in H2O and incubated at room temperature for 15 min. After the incubation period, 0.5 milliliter of Griess reagent was added. The optical density of the chromophore formed was read at 570 nanometers.
The consequences of anticonvulsant and antinociceptive activities were expressed as Mean A± SEM. The statistical significance of the differences between the groups was analyzed by one-way analysis of discrepancy ( ANOVA ) followed by the Dunnett ‘s multiple comparing trial.
Calculation of molecular and ADME belongingss
The molecular belongingss like TPSA, miLogP, figure of rotatable bonds and misdemeanors of Lipinski ‘s Rule-of-Five were calculated utilizing Molinspiration on-line belongings reckoner tool kit [ 28 ] . Topological polar surface country was used to cipher the per centum of Absorption ( % ABS ) harmonizing to the equation: % ABS = 109 – [ 0.345A- TPSA ] [ 21 ] .In vitro plasma protein adhering values were obtained from ADME reckoner.