Studies On Sesquiterpenoids And Other Constituents Of Three Herbal Medicines From Asteraceae

The traditional Chinese medicines (TCMs) with functions of Heat-clearing and toxin-resolving have been used to treat febrile disease due to heat-toxin syndrome in clinical. And modern pharmacological studies indicated these herbal medicines were used to treat influenza, cancer, diabetes, coronary heart disease, arthritis and cardiovascular disease because of possess anti-pathogenic microorganism, antiendotoxin, anti-inflammatory, and enhancing immunologic effects. Cancer is the leading death cause worldwide. At present, the main cancer therapies are surgery, radiotherapy and chemotherapy, and combined with adjuvant treatment with certain anticancer drugs, so search for new anticancer drugs are a rearch hot spot all the time. TCMs play an irreplaceable role in the prevention and treatment of cancer, and herein we gave an overview of antitumor activities of 72 TCMs being recorded in Chinese Pharmacopoeia,2010 version.In the course of our group continuing research on sesquiterpenoids from the Asteraceae plants, we have made systematic studies on chemical constituents from Ye-Ju-Hua and Yan-Guan-Tou-Cao and Kuan-Dong-Hua. Ye-Ju-Hua, as TCM, is the dried flowers of C. indicum of the Asteraceae, recorded in Chinese Pharmacopoeia, which is used to treat furunculosis, swelling and pain of eye, headache and dizziness and all kinds of inflammations, such as prostatitis, chronic pelvic inflammation, etc.; and Kuan-Dong-Hua is the dries flower buds of T. farfara of the Asteraceae, also recorded in Chinese Pharmacopoeia, being used for treatment of cough, bronchitis and asthmatic disorders; Yan-Guan-Tou-Cao, as a herbal medicine, is the whole plant of C. cernuum of the Asteraceae, being used in folk medicine to instead of C. divaricatum for treatment of anti-malarial and laryngitis, and more.Various chromatographic techniques, i.e. Silica gel, C18 reversed-phase Silica gel and Sephadex LH-20 for column chromatography and HPLC were used in the process of extraction, isolation and structural elucidation. And 129 compouds, including 29 new structures and two of them beared a rare polyacetylene skeleton, were elucidated on the basis of comprehensive spectroscopic methods, such as IR, UV, MS, CD and 1D/2D NMR, etc. The structure names, sketelon types and sources of these new compounds and sesquiterpeniods were showen in Table 1.60 compounds determined as sesquiterpenoids, flavonoids, polyacetylenes and triterpenoids, were isolated from the flowers of C. indicum; and 34 of them bearing 9 skeletons were elucidated as sesquiterpenoids, including 17 eudesmanes (11 of them as new ones),6 germacranes (4 of them as new ones),5 guaianes (including one new compound) and one new iphionane compoud; additionally,10 polyacetylenes, including 4 new ones were also isolated from the flowers of C. indicum. From the flower buds of T. farfara,25 compounds appearing as sesquiterpenoids, 2,2-dimethylchromans,5-hydroxymethylfurfural derivatives, alkaloids, fructofuranoside, steroids and triterpenoids were isolated; among these compounds,11 of them with 5 frameworks were elucidated as sesquiterpenoids, including 4 oplopananes (including one new compound),3 eudesmanes (including one new compound) and one new bisabolane, and 3 new artifact products with EtO groups were elucidated as (4R*)-6-(1-ethoxyethyl)-2,2-dimethylchroman-4-ol,5-ethoxymethyl-lH-pyrrole-2-carbaldehyde and 3-hydroxy-7-ethoxy-24-ethyl-cholest-5-ene; the absolute configurations of these new compounds were assigned by CD experiments.44 compounds including sesquiterpenoids, flavonoids, phenols, steroids, lignans and triterpenoids were isolated from the whole plant of C. cernuum; among these compounds,24 of them were elucidated as sesquiterpenoids bearing 8 frameworks, and more of them as sesquiterpene lactones, including 9 eudesmanolides,5 guaianolides (including one new compound) and one new eremophilenolide.In the dissertation,69 sesquiterpenoids with various skeletons were obtained, indicating that the sesquiterpenoids were their main components. The results can provide several scientific evidences for these herbs in chemotaxonomy, active components screening and treatment principles. And credible quality control standards can be afforded from the results to the effective components. While our results can offer some references for new dosage form development.