Separation and Determination of Eremophilenolides from Ligulariopsis shichuana by Capillary Zone Electrophoresis

A new method of capillary zone electrophoresis (CZE) was established by simultaneous assay of four eremophilenolides, 3β-acetoxy-9β-angeloyloxy-1β,10β-epoxy-8α-hydroxyeremophil-7(11)-en-8β (12)-olide (1), 3β-senecioyloxy -1β,10β-epoxy-8α-hydroxyeremophil-7(11)-en-8β (12)-olide (2), 6α-hydroxy-1β,10β-epoxy-8α-hydroxyeremophil-7(11)-en-8β (12)-olide (3) and 3β-acetoxy- 6β-angeloyloxy-1β,10β-epoxy-8α-hydroxyeremophil-7(11)-en-8β (12)-olide (4) in the Chinese herbal extract from Ligulariopsis shichuana. The optimum buffer system was 20 mM borate buffer (pH 10.00). Voltage was 25 kV and detection at 214 nm. Regression equations revealed linear relationships (correlation coefficients 0.9986, 0.9990, 0.9992 and 0.9995) between the peak area of each compound and its concentration. The relative standard deviations of migration times and peak areas were <1.35 and 3.94% within 1 day, respectively. The effects of several CE parameters on the resolution were studied systematically. The contents of four eremophilenolides in Ligulariopsis shichuana were successfully determined with satisfactory repeatability and recovery.     

假橐吾中四对新的倍半萜结构研究

从假橐吾全草中分离得到四对新的(1/2,3/4,5/6,7/8)和一对已知的（9／10） 8，9－开环艾里莫芬内酯型倍半萜，每一对均为C－8位差向异构体。它们的结构通 过波谱方法阐明并通过酰化或酯化分离后得到证实。活性筛选实验表明，1／2和3 ／4具有细胞毒活性。     

A New Highly Oxygenated Eremophilenolide from Ligulariopsis shichuana

a new highly oxygenated eremophilenolide was isolated from Ligulariopsis shichuana. Its structure was elucidated by NMR spectroscopic and X-ray diffraction methods.     

New Sesquiterpenes from Ligulariopsis Shichuana

A thorough investigation of Ligulariopsis shichuana afforded five new sesquiterpenes, including 1β,10β‐epoxy‐3α‐angeloyloxy‐9β‐acetoxy‐8α,11β‐dihydroxybakkenolide ( 1 ), 1β,7‐dihydroxy‐3β‐acetoxy‐noreremophil‐6(7),9(10)‐dien‐8‐one ( 2 ), 8α‐hydroxy‐3‐oxoeremophil‐1(2),7(11),9(10)‐trien‐8β(12)‐olide ( 3 ), 1β,10β‐dihydroxy‐3β‐acetoxyeremophil‐7(11),8(9)‐dien‐8(12)‐olide ( 4 ) and 1β,10β‐epoxy‐8,12‐dihydroxy‐3β‐acetoxy‐9β‐angeloyloxyeremophil‐7(11)‐en‐8,12‐disemiketal ( 5 ). Their structures were established by spectroscopic methods and 2D NMR techniques. In addition, bakkenolide ( 1 ) and eremophilenolides ( 5 ) showed antibacterial and cytotoxic activities.     

Two new eremophilenolides from the roots of Ligulariopsis shichuana and their anti-phytopathogenic fungal and antifeedant activities

Two new eremophilenolides, ligushicins A (1) and B (2), and two known compounds including β-sitosterol and ursolic acid were isolated from Ligulariopsis shichuana. The structures of new compounds were established on the basis of 1D and 2D NMR data and HRESIMS data interpretation. The absolute configuration of new compounds was assigned by ECD spectroscopy, and that of ligushicins A (1) was confirmed by X-ray diffraction analysis. The antifungal and antifeedant activities of new compounds were evaluated against four plant pathogenic fungi and third-instar larvae of Plutella xylostella, respectively. Ligushicins A (1) and B (2) exhibited potent antifungal activity against Botrytis cinerea and Fusarium oxysporum with minimum inhibitory concentration (MIC) values ranging from 50 to 100 mg/L, while they also exhibited weak antifeedant activities.