Chemistry On Secondary Metabolites From ?dim5 Of Neurospora Crassa

Neurospora crassa is one of model fungi belonging to the sordariacia,most wildly used in the laboratory.This fungus is branched in mycelia with multineuclei in the transparent orange conidia.Elucidating the chemical structure of the secondary metabolites in N.crassa and using these metabolites as standards will help to reveal the mechanisms for gene cluster regulation mechanisms.The strain used in this study is N.crassa?dim5 mutant.Dim5 is histone methyltransferase,closely related to the formation of heterochromatin.It has been shown that deletion of dim5 led to increased versatility in chemical profiles and upregulated levels in accumulation of secondary metabolites.Therefore,the?dim5mutant strains was used in this study for elucidaing the chemical constituents of its secondary metabolites.The main research contents and results were summarized as follows:1.Cultivation of the?dim5 mutant strain of Neurospora crassa by rice.The culture was extracted with ethyl acetate to separate the mycelium.The ethyl acetate extract of mycelium was gained.Subsequently,the secondary metabolites of ethyl acetate extract with higher chemical diversity were analyzed by TLC,leading to the localization of target constituents.2.The secondary metabolites were qualitatively analysed by TLC followed by extraction using ethyl acetate extract,and subsequently isolated by combined methods of chromatography including but not limited to silica gel column chromatography,Sephadex LH-20 andpreparative TLC.Their structures were elucidated by means of various modern spectroscopic techniques(GC-MS,LC-MS,¹H-NMR,¹³C-NMR,DEPT,¹H-¹HCOSY,HSQC,HMBC,single crystal X ray diffraction etc).Eleven compounds were identified.These include 3,6-diisobutyl piperazine-2,5-dione,nonanoic acid,lauric acid,hexadeca-3,5,11,13-tetraenoic acid,linoleic acid,?4-hydroxy-phenyl?-acetic acid,4-hydroxy-benzoic acid,ergosterol,formic acid-1-amino-2-?4-hydroxy-phenyl?-ethyl este,3-?2,5-dimethoxy phenyl?-2-?2-hydroxy benzoyl?-furo[3,2-c]chromen-4-one,1-?4-methoxy phenyl?-3a-methyl-4-oxo-3,3a,4,5-tetrahydro cyclopenta[c]N-4-methoxy benzenesulfonamide quinoline-2,2-N,N-dimethyl urea.In addition,hexadeca-3,5,11,13-tetraenoic acid,and formic acid1-amino-2-?4-hydroxy-phenyl?-ethyl este are new compounds,3-?2,5-dimethoxy phenyl?-2-?2-hydroxy benzoyl?-furo[3,2-c]chromen-4-one is found for the first time in the living organism and it is the metabolic product of the pks6,and 1-?4-methoxy phenyl?-3a-methyl-4-oxo-3,3a,4,5-tetrahydro cyclopenta[c]N-4-methoxy benzenesulfonamide quinoline-2,2-N,N-dimethyl-urea is the metabolic product of the nrps-1.