Three Types of Isocoumarins with Unusual Carbon Skeletons from Artemisia dubia var. subdigitata and Their Antihepatoma Activity

Ten novel isocoumarins,including four pairs of enantiomers,were isolated from Artemisia dubia var.subdigitata(Asteraceae).Compounds 1,2 and 3a/3b possessed a unique 6/6/6-tricyclic system comprising an unusual 1-(2-methylcyclohexyl)propan-1-one moiety fused with isocoumarin core skeleton.Compounds 4a/4b were characterized as an unexpected 2,5-dimethylcyclohexan-1-one scaffold,and compounds 5a/5b and 6a/6b were rare 1,2-seco-isocoumarin.Their structures and absolute configurations were elucidated through spectroscopic data,X-ray crystallography,ECD and NMR calculations with DP4+analyses.Plausible biosynthetic pathways were proposed from the naturally occurring isocoumarin.Network pharmacological analysis suggested that the targets of compound 1 were significantly enriched in the cell cycle and Pl3K-Akt signaling pathway.The molecular docking revealed that compound 1 had high binding affinity with CDK2(total score:6.8717).Furthermore,compounds 1 and 2 exhibited inhibitory activity on three human hepatoma cell lines,with inhibitory ratios of 85.1% and 84.5%(HepG2),88.2% and 87.3%(Huh7),and 69.2% and 69.1%(SK-Hep-1)at 200μmol·L^(-1),respectively.

Artemdubinoids A-N:novel sesquiterpenoids with antihepatoma cytotoxicity from Artemisia dubia

In pursuit of effective agents for hepatocellular carcinoma derived from the Artemisia species,this study built upon initial findings that an ethanol(EtOH)extract and ethyl acetate(EtOAc)fraction of the aerial parts of Artemisia dubia Wall.ex Bess.exhibited cytotoxicity against HepG2 cells with inhibitory rates of 57.1%and 84.2%(100μg·mL−1),respectively.Guided by bioactivity,fourteen previously unidentified sesquiterpenes,artemdubinoids A–N(1–14),were isolated from the EtOAc fraction.Their structural elucidation was achieved through comprehensive spectroscopic analyses and corroborated by the comparison between the experimental and calculated ECD spectra.Single crystal X-ray diffraction provided definitive structure confirmation for artemdubinoids A,D,F,and H.Artemdubinoids A and B(1–2)represented unique sesquiterpenes featuring a 6/5-fused bicyclic carbon scaffold,and their putative biosynthetic pathways were discussed;artemdubinoid C(3)was a novel guaianolide derivative that might be formed by the[4+2]Diels–Alder reaction;artemdubinoids D and E(4–5)were rare 1,10-seco-guaianolides;artemdubinoids F–K(6–11)were chlorinecontaining guaianolides.Eleven compounds exhibited cytotoxicity against three human hepatoma cell lines(HepG2,Huh7,and SKHep-1)with half-maximal inhibitory concentration(IC50)values spanning 7.5−82.5μmol·L^(−1).Artemdubinoid M(13)exhibited the most active cytotoxicity with IC50 values of 14.5,7.5 and 8.9μmol·L^(−1)against the HepG2,Huh7,and SK-Hep-1 cell lines,respectively,which were equivalent to the positive control,sorafenib.

烈香杜鹃精油和牛尾蒿精油对门源草原毛虫的生物活性

采用浸叶法和点滴法测定烈香杜鹃(Rhododendrom anthopogonoides Maxim)、牛尾蒿(Artemisa dubiaWall.ex Bess)植物精油对门源草原毛虫(Gynaephora menyuanensis)(鳞翅目Lepidoptera:毒蛾科Lymantriidae)6龄幼虫的生物活性。结果表明,烈香杜鹃和牛尾蒿植物精油对幼虫具有很强的胃毒、触杀活性和拒食作用,以及生长抑制作用。烈香杜鹃精油对门源草原毛虫幼虫的生物活性高于牛尾蒿精油。

艾、野艾及细叶艾的FTIR直接鉴别

目的:为了直接准确地鉴别艾、野艾及细叶艾。方法:采用傅里叶变换红外光谱法直接测定艾、野艾及细叶艾的红外光谱。结果:艾、野艾及细叶艾的红外光谱吸收差别较大。结论:可以采用FTIR法直接、快速、准确地对艾、野艾及细叶艾进行区别鉴定。

牛尾蒿、灌木亚菊挥发油对烟草甲防治作用研究

为有效防治烟草仓储害虫,本实验通过熏蒸和触杀试验测试牛尾蒿和灌木亚菊挥发油对烟草甲成虫的生物活性。结果显示:牛尾蒿、灌木亚菊挥发油对烟草甲触杀活性的半数致死量分别为19.30 μg/头和25.92 μg/头,熏蒸作用的半数致死浓度分别为50.89 mg/L和31.35 mg/L。牛尾蒿和灌木亚菊挥发油对烟草甲具有一定的防治作用。

牛尾蒿两变种精油的化学成分

本文以气相色谱-质谱计算机联用的方法分析了牛尾蒿原变种Artemisia dubia var.dubia及无毛变种A.dubia var.subdigitata的精油化学成分,共鉴定出82种化合物,其中萜类50种,芳香类12种,脂肪族类20种。经比较研究表明,这两变种的精油中有39种化合物(27种萜类,5种芳香类和7种脂肪族类化合物)相同,而它们的差别在于牛尾蒿无毛变种中二环、三环倍半萜、芳香类及脂肪族类化合物的类型比原变种多。从精油的萜类化学组成特点来看,这两个变种的萜类化合物环化程度比蒿亚属植物高,而与龙蒿亚属植物相近。因此,这两个变种归属于龙蒿亚属较合适。

野艾色素的研究

从野艾嫩枝叶中提制的色素,主要成分为叶绿素a和叶绿素b。野艾色素耐热性好。金属A1^(3+)和Ca^(2+)对野艾色素有不良影响,在实际生产中不能使用铝制品,不能与钙接触。低浓度的Fe^(3+)、Cu^(2+)和Zn^(2+)以及高浓度的Sn^(2+)对色素能起增色作用。

5种蒿属植物提取物对马铃薯晚疫病的抑菌活性研究

以牛尾蒿、黑蒿、艾蒿、青蒿及茵陈蒿5种蒿属植物的乙醇提取物为供试药剂,采用带毒平板法测定蒿属植物的乙醇提取物对马铃薯晚疫病pn5502和pn7604菌株的抑菌活性,采用硅胶柱层析法对牛尾蒿的乙醇提取物的抑菌活性成分进行追踪,筛选抑制马铃薯晚疫病菌活性成分。结果表明:当各粗提物浓度为1 mg/mL时,对供试菌株均有一定的抑菌活性,其中牛尾蒿粗提物的抑菌活性最强,对菌株pn5502和pn7604的抑菌率分别为89.04%和71.38%。其中,馏分Fr_(1)浓度为0.5 mg/mL时,对2株菌的抑制活性高达100%。馏分Fr_(1)对pn5502的EC_(50)为7.4733μg/mL,对pn7604的EC_(50)为9.4634μg/mL。因此,5种蒿属植物的乙醇提取物对2株马铃薯晚疫病均有一定的抑菌活性,其中牛尾蒿馏分Fr1抑制作用最强,抑菌活性高于阳性对照药剂霜脲·锰锌,其抑菌活性成分值得进一步研究。