30891.三種苯并吡喃類黃烷酮天然產(chǎn)物的全合成研究

1、獨(dú)創(chuàng)性聲明本人聲明所呈交的論文是我個(gè)人在導(dǎo)師指導(dǎo)下進(jìn)行的研究工作及取得的研究成果。盡我所知，除了文中特別加以標(biāo)注和致謝的地方外，論文中不包含其他人已經(jīng)發(fā)表或撰寫過的研究成果，也不包含為獲得寧夏大學(xué)或其它教育機(jī)構(gòu)的學(xué)位或證書而使用過的材料。與我一同工作的同志對(duì)本研究所做的任何貢獻(xiàn)均已在論文中作了明確的說明并表示了謝意。研究生簽名：孓吞l曷禹。時(shí)間：刃／∥年r月f日關(guān)于論文使用授權(quán)的說明本人完全了解寧夏大學(xué)有關(guān)保留、使用學(xué)位論文的規(guī)定，即：

2、學(xué)校有權(quán)保留送交論文的復(fù)印件和磁盤，允許論文被查閱和借閱，可以采用影印、縮印或掃描等復(fù)制手段保存、匯編學(xué)位論文。同意寧夏大學(xué)可以用不同方式在不同媒體上發(fā)表、傳播學(xué)位論文的全部或部分內(nèi)容。(保密的學(xué)位論文在解密后應(yīng)遵守此協(xié)議)研究生簽名導(dǎo)師簽名：：7撕辰嬲時(shí)間：勵(lì)／孕年歲月糾日日擱：伊‘f年妨刁日AbstractThisthesisaimsatthestudiesonthetotalsynthesisofnaturalbenzoprany

3、lflavanoidsThefirsttotalsynthesisofthreenaturallyoccurringflavonoidsand26intermediateswerefinished，Thestructuresofthesecompoundsinvolved9knowncompoundsandl7newcompoundswereelucidatedbasedOllspectroscopicmethodsincludingn

4、uclearmagneticresonance，IRandmassspectrometryChapterI：ReviewNaturallyoccurringflavonoidswerereviewedontheircharacterizationofstructure，pharmacologicalactivities，distributioninplantsandtotalsynthesisChapterII：Thestudyonto

5、talsynthesisof(士)malaysianoneAand(士)tanariflavanonesBTwonaturalBenzopranylflavonoidshavebeensynthesizedthroughintermolecularlyandintramolecularlycatalizedcyclization，prenylation，protectionanddeprotectionofhydroxylgroup，a

6、ldolcondensationinfivestepsstartingfromcheap2，4，6TrihydroxyacetophenoneandCitralwithtotalyield129％and104％，respectivelyThekeystepwere5formaldehyde8hydroxy2[4’methyl3Lpenteneyl]dihydro1benzopyran(8)wassynthesizedfrom3，4dih

7、ydroxybenzaldehydeandcitralinanhydrouspyridineto21％yield，toimprovetheyieldofcompound8fromto30％bysimultaneousadditionofthedehydratingagent(ie，Na2S04，MgS04)inthereactionsystemChapterⅢ：Thestudyontotalsynthesisof5hydroxy2一me

8、thyl2(4’methyl3’pentenyl)2HlbenzopyranflavonoidsThechapterpresentedthesynthesisof5hydroxy2一methyl一2一(4“methyl3’一pentenyl)2H—l—benzopyranflavonoidsthroughthroughintermolecularlyandintramolecularlycatalizedcyclization，prot

9、ectionanddeprotectionofhydroxylgroup，aldolcondensationinfivestepsstartingfromcheap2，4，6TrihydroxyacetophenoneandCitral、)lrithtotalyield118％Keywords：(士)malaysianoneA，(士)一tanariflavanonesB，flavanone，totalsynthesis，benzopra