Discovery Of Quinone Reductase Inducers From Salvia Miltiorrhiza

The chemical constituents from dichlormethane fraction of 95%ethanol extract of Salvia miltiorrhiza were studied.Fifteen tanshinones were separated and identified as 15,16-dihydrotanshinoneâ… ,tanshinoneâ… ,tanshinoneâ…¡A,tanshinonâ…¡B,tanshindiol B, cryptotanshinone,trijuganone C,17-hydroxycryptotanshinon,1,2-dihydrotanshinoneâ… , tanshindiol A,miltirone,1-oxomiltirone,4-methylenemiltirone,1,2-didehydromiltirone, danshenxinkun B,by thesis physical-chemical properties.It is becoming more and more important that prevent tumor in the first developing stage.Phaseâ…¡enzymes is considered to be significant to protect human from cancer and quinone reductase is one of them.The evaluation of the QR induction of compounds is becoming much more valuable than before.In the thesis,the QR induction activities of tanshinones were evaluated and indicated that miltirone(11), 1-oxomiltirone(12),4-methenemiltirone(13) and 1,2-didehydromiltirone(14) showed high QR activities with the CD value of 0.92μM,0.40μM,0.46μM and 1.04μM, respectively.The high cost of time and money limit a lot for this,so we try to find an easy and rapid method for the discovery of compounds with QR induction activities.Usually,the Keapl and Nrf2 bind to each other,then the Nrf2 is part from Keapl and transferred to nucleus,leading to the expression of phaseâ…¡enzymes when exogenous substances like oxidants and radicals invaded.GSH shares the same -SH with the Keapl and can bind to substances that able to bind to Keap1.The experiments of conjugation of GSH with tanshinones showed that tanshinones which had similar structure with miltirone all had high activities,which were consistent with the results of cells assay.The methods were used to discover the QR inducers from the CH₂Cl₂ extract of danshen after having the reference compounds and validated the results with cell assay. In order to determine the conjugation site of miltirone with GSH,the NMR experiments were employed and the results showed conjugation happened at C-14 of miltirone.Also, we studied the cleavage patterns of tanshinones and found some new cleavage pathway.