Biologicallypotentdioxomolybdenum(VI)complexeswithnitrogen-sulfurandnitrogen-oxygendonarligands:Synthesis,characterisationandantimicrobialactivityINTRODUCTIONMolybdenumisanimportanttransitionelement,whichhasamajorroleastraceelementsandisanin-dispensableconstituentofenzymesthatareinvolvedinthefunctionofnitrogenfixingnitrogenase[1].
Alargenum-berofstableandaccessibleoxidationstatesandcoor-dinationnumberrendermolybdenumtobeaversatiletransitionelement.
Molybdenumistheonlyelementinthesecondandthirdtransitionserieswhichplaysmajorroleastraceelementinenzymes.
Thepresenceofcis-dioxymolybdenumcation[MoO2]+2intheoxidizedformofcertainmolybdoenzymeshasrecentlygeneratedtre-AshuChaudhary1*,R.
V.
Singh21DepartmentofChemistry,BanasthaliUniversity,Rajasthan,(INDIA)2DepartmentofChemistry,UniversityofRajasthan,Jaipur-302004,(INDIA)E-mail:ashuchaudhary21@gmail.
comReceived:24thJuly,2008;Accepted:29thJuly,2008mendousinterest[2].
Thecis-[MoO2]+2centredominatesthechemistryofdomolybdenum(VI)complexes[3]andparticipatesinmanyoxygenatomtransferreactions[4-6].
Schiffbasesareanimportantclassofligandsinco-ordinationchemistryandhavemanyapplications[7]invariousfields.
ThechemistryofSchiffbasecomplexescontinuestoattractmanyresearchers[8,9]becauseoftheirwideapplicationsinfoodindustry,dyeindustry,ana-lyticalchemistry,catalysis,antimicrobialactivity,agrochemicalactivity[10]andpharmacologicalapplications[11].
TheSchiffbaseshavebeenfoundtobeactiveagainstdifferenttypesofbacteriaandviruses.
IthasnowbeenobservedthatsomeoftheseshowincreasedKEYWORDSDioxomolybdenum(VI)complexes;Spectralstudies;Schiffbase;Antimicrobialstudies.
ABSTRACTMolybdenum(VI)complexesof3,4,5-trimethoxybenzaldehydethiosemicarbazone(TBTSCZH),3,4,5-trimethoxybenzaldehydesemicarbazone(TBSCZH),3,4,5-trimethoxy-benzaldehydebenzothiazoline(TBBZTH)and3,4,5-trimethoxybenzaldehyde-S-benzyldithiocarbazate(TBDTCZH)havebeensynthesizedandcharacterizedbyphysico-chemicalandspectroscopicstudies.
ThecomplexesMoO2(L)2(whereLrepresentedthedeprotonatedformoftheligands),wereformedbythereactionsbetweendioxobis(2,4-pentanedionato-O,O')molybdenum(VI)andtheligandsTBTSCZH,TBSCZH,TBBZTHandTBDTCZHbyusingbothtechniques(thermalandmicro-wave).
Thestructuralfeaturesofthesemolybdenumcomplexeswereex-ploredbyIR,1HNMR,13CNMRandmolecularweightdeterminations.
Anoctahedralarrangementofligandsaroundthecentralmolybdenumatomisproposed.
Allthefourligandsandtheircomplexeshavebeenscreenedfortheirbiologicalactivityonseveralpathogenicfungiandbacteriaandthedatashowgoodactivityofthesecomplexesandligands.
2008TradeScienceInc.
-INDIAFullPaperICAIJ,3(3),2008[188-192]AnIndianJournalTradeScienceInc.
Volume3Issue3September2008InorganicCHEMISTRYAshuChaudharyandR.
V.
Singh189FullPaperICAIJ,3(3)September2008InorganicCHEMISTRYInorganicCHEMISTRYAnIndianJournalactivitywhenadministeredintheformofazomethinemetalcomplexes[12].
Inviewoftheimportanceofthedioxomolybdenum(VI)complexes,wehavesynthesizedandcharacterizedsomenewcomplexesofthesaidpo-tentialbidentateligands.
EXPERIMENTALAllthechemicalsandsolventsusedweredriedandpurifiedbythestandardmethods.
Dioxobis(2,4-pentanedionato)molybdenum(VI)waspreparedac-cordingtotheliteraturemethod[13].
PreparationoftheLigandsThedifferentrouteswereemployedforthesynthe-sisoftheligands.
Theseare-1.
MicrowaveassistedsynthesisFormicrowaveassistedsynthesisoftheligandsTBTSCZH,TBSCZH,TBBZTHandTBDTCZHthethiosemicarbazide,semicarbazidehydrochloride,2-aminothiophenolandS-benzyldihiocarbazatewerere-actedwith3,4,5-trimethoxybenzaldehydeinethanolicmedia,usingaconventionalmicrowaveoven,wheretheconsumptionofethanolassolventisverylittle(2-3ml).
Thereactionswerecompletedinashortperiod(4-8minutes).
ThecompletionofthereactionischeckedbyTLC.
2.
ConventionalheatingsynthesisForthecomparisonpurpose,aboveligandswerealsosynthesizedbythethermalmethod.
Forthistheweighedamountsof3,4,5-trimethoxybenzaldehydeandthiosemicarbazide,semicarbazidehydrochlorideand2-aminothiophenolandS-benzyldihiocarbazateweremixedtogetherin100mlethanolin250mlbeaker.
Thecontentswererefluxedfor4-16hrs.
onanoilbath.
Thesolidproductswereprecipitated.
Theseweredriedinvacuumandrecrystallizedfromthesamesolvent.
AcomparisonbetweenthermalmethodandmicrowavemethodhasbeengiveninTABLE1.
Theligandsusedare:Preparationofthecomplexes1.
MicrowaveAssistedMethod:Inmicrowaveas-sistedsynthesisthereactionsofdioxobis(2,4-pentanedionato-O,O')molybdenum(VI)withtheligands(TBTSCZH,TBSCZH,TBBZTHandTBDTCZH)werecarriedoutin1:2molarratios,using2-3mlofdrymethanolasasolventusingmi-crowaveoven.
Theproductswererecoveredfromthemicrowaveovenanddriedunderreducedpres-sure.
Theresultingproductswererepeatedlywashedwithdrycyclohexaneandthenfinallydriedat40-60o/0.
5mmfor3-4hours.
2.
ConventionalHeatingMethod:Thesemolybdenum(VI)complexeswerealsosynthesizedbythether-malmethod.
Inthethermalmethodinsteadof4-7minutesreactionswerecompletedin14-16hoursandyieldofproductswerealsolesserthanobtainedbythemicrowaveassistedsynthesis(TABLE1).
RESUTLSANDDISCUSSIONThereactionsofthedioxobis(2,4-pentanedionato-O,O')molybdenum(VI)withthesaidmonofunctionalHCOCH3OCH3OCH3NNHCSNH2HCOCH3OCH3OCH3NNCSHNH2(TBTSCZH)HCOCH3OCH3OCH3NNCOHNH2HCOCH3OCH3OCH3NNHCONH2(TBSCZH)HCOCH3OCH3OCH3NHSHCOCH3OCH3OCH3NHSHCOCH3OCH3OCH3NNHCSSCH2C6H5HCOCH3OCH3OCH3NNCSHSCH2C6H5(TBBZTH)(TBDTCZH).
190Biologicallypotentdioxomolybdenum(VI)complexesFullPaperICAIJ,3(3)September2008AshuChaudharyandR.
V.
Singh191FullPaperICAIJ,3(3)September2008InorganicCHEMISTRYInorganicCHEMISTRYAnIndianJournalservedintheregion3430-3350cm-1intheligandsat-tributedtoasymmetricandsymmetricmodesoftheNH2groupremainatnearlythesamepositioninthecom-plexes,indicatingthenon-involvementofthisgroupinchelation.
InadditiontothisthespectrumoftheligandTBDTCZHshowsdoubletat2900and2950cm-1,whichcanbeattributedtosymmetricandasymmetricvibrationsofS-CH2-C6H5grouping16andreducedtoaweakdoubletinthespectraofthecomplexes.
InthespectrumoftheligandTBBZTHtheabsenceof(SH)at2600-2530cm-1and(C=N)at1620-1590cm-1isastrongevidencefortheringstructure.
Oncomplexation,thebandat3240-3150cm-1duetoNHstretchingvibrationsofthebenzothiazoline,disap-pearsandabandat1600cm-1isobserveddueto(C=N)vibrations.
Thechelationofthisbenzothiazolineandthesaidligandsthroughtheazomethinenitrogenandthiolicsulphurfurthergetssupportbytheappear-anceofthenewbandsatca.
650cm-1,435cm-1and360cm-1,inthespectraofthecomplexesdueto(Mo-O),(MoN)and(Mo-S),respectively.
Adoubletinthespectraofthecomplexesatca.
910cm-1,whichmaybeassignedtosym(O=Mo=O)andasy.
(O=Mo=O),respectively,indicatesthecisMoO2struc-ture.
1HNMRspectraThebondingpatterndiscussedabovegetsfurthersupportbytheprotonmagneticresonancespectralstud-iesoftheligandsandtheircomplexes.
The1HNMRspectraoftheligandsTBTSCZH,TBSCZHandTBDTHshowsignalsdueto–NHgroup(10.
65-10.
98ppm)and–SHgroup(7.
88-7.
96ppm).
Incaseofthecorrespondingcomplexthesignalsdueto–NHand–SHprotonsoftheligandunitdisappearindi-catingdeprotonationandsimultaneouscovalentbondformationthroughnitrogenandsulphur.
Allthesaidfreeligandsandtheirmolybdenumcomplexesshowmultip-letsintheregion6.
25-8.
80ppmattributabletoaro-maticprotons,whichappearalmostatthesameposi-tionintherespectiveligands.
TheNH2protonsgivesingletat3.
48-4.
20intheligandsTBTSCZHandTBSCZHaswellastheircorrespondingmolybdenum(VI)complexes.
ItshowsthattheNH2groupisnottakingpartinthecomplexation.
The1HNMRspectrumoftheligandTBBZTHshowsthesignalof–NHprotonat5.
40ppmwhichfoundabsentinthespectraofthemolybdenum(VI)complexesconfirmingthedeprotonationof–NHgroupandcoordinationofmolybdenumwithnitrogenatom.
TheH-C=Nsignalisfoundinupfieldorshieldedre-gioninbenzothiazolineligandanditsmolybdenum(VI)complexesascomparedtothethiosemicarbazone,semicarbazoneanddithiocarbazateandtheirmolybdenum(VI)complexes.
ThespectrumoftheligandTBDTCZHalsoshowsanadditionalpeakat1.
78ppmduetoS-CH2-Phprotonsandthispeakappearsindeshieldregioninitscorrespondingmetalcomplex.
13C-NMRspectraThe13CNMRspectraofoneoftheligandanditscorrespondingmetalcomplexeshavebeenrecordedinCDCl3.
Thechemicalshiftvaluesofthecarbonatomattachedtotheazomethinenitrogen,thiolicsulfuroramidooxygen,showconsiderableshiftwhichfurthersupporttheproposedcoordinationinthecomplexes.
Onthebasisoftheabovestudiesthecoordinationpatternshowninfigure1isconcluded.
AntimicrobialstudiesBioefficiencyoftheparentligandsandtheircom-plexeswastestedinvitroforthegrowthinhibitingpo-tentialagainstvariousfungalandbacterialstrainsusingRadialGrowthMethodandPaperDiscTechnique,re-spectively.
FungalstrainsM.
phaseolina,F.
oxysporumandBacterialstrainsS.
aureusandK.
aerogenous,wereused.
Thebiocidalactivityhavebeencomparedwiththeconventionalfungicide.
Bavistinandtheconven-tionalbactericide,Streptomycin.
AllthescreeningdataaregiveninTABLES3and4.
Itisapparentthatsulfurcontainingcompoundsaremoretoxicthantheoxygencontainingcompounds.
ItXMoXNOONWhere,X=SandOandNXisthedonorsystemoftheligandsFigure1.
192Biologicallypotentdioxomolybdenum(VI)complexesFullPaperICAIJ,3(3)September2008
昨天有分享到"2021年Vultr新用户福利注册账户赠送50美元"文章,居然还有网友曾经没有注册过他家的账户,薅过他们家的羊毛。通过一阵折腾居然能注册到账户,但是对于如何开通云服务器稍微有点不对劲,对于新人来说确实有点疑惑。因为Vultr采用的是预付费充值方式,会在每月的一号扣费,当然我们账户需要存留余额或者我们采用自动扣费支付模式。把笔记中以前的文章推送给网友查看,他居然告诉我界面不同,看的不对...
Hostadvice主机目录对我们的服务进行了测试,然后给PQ.hosting颁发了十大WordPress托管奖。为此,宣布PQ.Hosting将在一周内进行折扣优惠,购买和续订虚拟服务器使用优惠码:Hostadvice ,全部优惠10%。PQ.hosting,国外商家,成天于2019年,正规公司,是全球互联网注册商协会 RIPE 的成员。主要是因为提供1Gbps带宽、不限流量的基于KVM虚拟的V...
官方网站:点击访问亚州云活动官网活动方案:地区:美国CERA(联通)CPU:1核(可加)内存:1G(可加)硬盘:40G系统盘+20G数据盘架构:KVM流量:无限制带宽:100Mbps(可加)IPv4:1个价格:¥128/年(年付为4折)购买:直达订购链接测试IP:45.145.7.3Tips:不满意三天无理由退回充值账户!地区:枣庄电信高防防御:100GCPU:8核(可加)内存:4G(可加)硬盘:...
avmoo.com为你推荐
netlife熊猫烧香是怎么制作的嘀动网动网和爱动网各自的优势是什么?同ip站点查询如何查看几个站是不是同IPwww.522av.com在白虎网站bhwz.com看电影要安装什么播放器?789se.comhttp://gv789.com/index.php这个网站可信吗?是真的还是假的!www.544qq.COM跪求:天时达T092怎么下载QQavtt4.comCOM1/COM3/COM4是什么意思??/抓站工具抓鸡要什么工具?广告法请问违反了广告法,罚款的标准是什么www.aise.com怎么观看网页一些视频?
北京主机租用 如何注销域名备案 namecheap 电影服务器 isatap 香港cdn softbank官网 外国域名 网站保姆 工信部icp备案号 免费吧 如何注册阿里云邮箱 服务器硬件防火墙 免费的asp空间 中国域名 ledlamp 服务器防御 hdsky 香港博客 sonya 更多