Study On Chemical Constituents From Petroleum Ether And N-buoh Fractions Of Chimaphila Japonica Miq. And Their Cytotoxic Activities

The chemical constituents from the petroleum ether and n-Bu OH fractions of Chimaphila japonica Miq.and their cytotoxic activities of human tumor cell lines were investigated in this study.C.japonica belongs to Chimaphila genus in Ericaceae family,which is mainly distributed in Jilin and Liaoning Provinces of China,Korea,Russia and Japan.It has been reported that the ethanol and water extracts of C.japonica have various pharmacological effects,including anti-inflammatory,analgesic and anti-tumor.In addition,it can be used as a diuretic and urethral anti-inflammatory agent to treat all kinds of edema,water.However,there are few studies on the active components of this plant.The phylogeny of medicinal plants indicates that there is a certain correlation among plant phylogeny,chemical composition and medicinal efficacy.Chimaphila and Pyrola are closely related,and their constituents are very similar,mainly containing terpenoids,sterols,flavonoids,quinones.Meanwhile,they have anti-tumor,anti-inflammatory,anti-oxidation and other pharmacological activities.Therefore,the further study of this plant is of great significance to the development and utilization of superior resources in Changbai Mountain area.Twenty five compounds were isolated from the petroleum ether and n-Bu OH fractions of C.japonica using silica gel column chromatography,Sephadex LH-20 gel column chromatography and recrystallization.The chemical structures of the monomer compounds were determined by the physical and chemical properties,spectral analysis(¹H-NMR and ¹³C-NMR)and related literature,including nine triterpenoids:α-amyrin（1）,uvaol（2）,triptohypol E（3）,ursolic acid（4）,2α,3α,23-trihydroxyurs-12-en-28-oic acid（5）,3-epi-corosolic acid（6）,corosolic acid（7）,asiatic acid（8）,taraxerol（9）;six flavonoids:quercetin（10）,quercetin-3-O-α-L-（5’’-O-acetyl）-arabinofuranoside（11）,quercitrin（12）,kaempferol（13）,juglanin（14）,kaempferol-3-O-α-L-5’’-acetyl-arabinofuranoside（15）;two sterols:β-sitosterol（16）,daucosterol（17）;two quinonoids:chimaphilin（18）,3,4-dihydro-4-hydroxy-2,7-dimethyl-naphthalen-1（2H）one（19）;one aldehyde:5-hydroxymethylfurfural（20）;one phenolic glycoside:isohomoarbutin（21）;three megastigmane glycosides:（6S,9S）-roseoside（22）,（6R,9S）-9-hydroxymegastigma-4,7-dien-3-one-9-O-β-D-glucopy ranoside（23）,3β-hydroxy-7,8-dihydro-4-oxo-ionol-9-O-β-D-glucopyranoside（24）,and one lignin:koreanaside A（25）.Among them,compounds 11,15,and 23-25 were firstly isolated from the Ericaceae family.Compounds 1-3,5-8,12,14,17,19,20,and22 were reported from genus Chimaphila for the first time and compounds 4,9,10,13,and 16 were obtained from this plant for the first time.The results showed that compounds 2,7,16 and 18 exhibited certain inhibitory effects on three tumor cell lines（A549,He La and SK-Hep1）at 30μM.The results showed that compounds 2,7,16 and 18 exhibited certain inhibitory effects on three tumor cell lines.Compounds 7and 18 showed similar cytotoxic activity in human lung cancer cells（A549）compared with doxorubicin,with IC₅₀values of 5.21±1.42 and 1.25±1.14μM,respectively.Compounds 7,16 and 18 showed similar tumor cytotoxic activity in human cervical cancer cells（He La）,with IC₅₀values of 6.19±1.51,1.96±0.22 and 1.21±0.47μM,respectively.Compounds 16 and 18 exhibited similar tumor cytotoxic activity in human hepatoma cells（SK-Hep1）with IC₅₀values of 1.52±0.32 and 2.56±0.63μM,respectively.In this study,the chemical constituents of C.japonica were further understood,and clarified its cytotoxic active components,which provided a scientific basis for the utilization of this plant.