Chemical Constituents Of Ligularia Atroviolacea And Taraxacum Mongolicum And Studies On The Preparation Of Isocholorogenic Acids From Laggera Pterodonta

This dissertation dealt with the chemistry of the natural resources of three folk medical plants,Ligularia atroviolacea(Franch.)Hand.-Mazz.(Asteraceae), Taraxacum mongolicum Hand.-Mazz.(Asteraceae)and Laggera pterodonta(DC.) Benth.(Asteraceae).The thesis is composed of four chapters.Chapterâ… Phytochemieal Investigation and Evaluation of Anti-HBV Activity of Ligularia atroviolaceaLigularia atroviolacea was distributed in the northwestern Yunnan province, China.Previous investigation of the same plant collected from Yunnan Province led to the isolation of eremophilane derivatives.These interesting findings have prompted us to a phytochemical examination of Ligularia atroviolacea grown in Yunnan.The compounds were isolated by means of silica gel column chromatography,preparative thin layer chromatography and recrystallization,etc. The structures of these compounds were elucidated by spectroscopic experiments (¹H-NMR,¹³C-NMR,¹H-¹H COSY,NOESY,HMBC,HSQC,ESI-MS,HR-MS, UV,IR,X-ray,etc)and chemical methods.24 compounds have been isolated and elucidated from Ligularia atroviolacea,and nine of them are new compounds (â… -2～Ⅰ-10).1.8β-H-eremophil-3,7(11)-dien-12,8α;15,6α-diolide(â… -1);2.8β-Hydroxy-eremophil-3,7(11)-dien-12,8α;15,6α-diolide(â… -2);3.8β-Methoxy-eremophil-3,7(11)-dien-12,8α;15,6α-diolide(â… -3);4.Eremophil-3,7(11),8-trien-12,8;15,6α-diolide(â… -4);5.3β-Angeloyloxy-eremophil-7(11)-en-12,8β-olide-15-oic acid(â… -5);6.1α-Chloro-6β-isobutyroxy-9-oxo-10β-hydroxy-furanoeremophilane(â… -6);7.10β-H-8-oxo-eremophil-3(4),6(7)-dien-12,15-dioic acid(â… -7);8.10α-H-8-oxo-eremophil-3(4),6(7)-dien-12,15-dioic acid(â… -8);9.8β-[Eremophil-3',7'(11')-dien-12',8'α;5',6'α-diolide]-eremophil-3,7(11)-dien-12,8α;15,6α-diolide(â… -9); 10.Ligulatrovine A(â… -10);11.Furanoeremophil-3-en-15,6α-olide(â… -11);12.Furanoeremophil-15β,6α-olide(â… -12);13.1α-Hydroxy-6β-isobutyroxy-9-oxo-10β-H-furanoeremophilane(â… -13);14.1α-Hydroxy-6β-isobutyroxy-9-oxo-10α-H-furanoeremophilane(â… -14);15.1α,10β-Dihydroxy-6β-angeloyloxy-9-oxo-furanoeremophilane(â… -15);16.8β-Hydroxy-eremophil-7(11)-en-12,8α;15,6α-diolide(â… -16);17.3β-Angeloyloxy-8β-H-eremophil-7(11)-ene-12,8α;14β,6α-diolide(â… -17);18.3β-(2'-methylbutanoyloxy)-8β-H-eremophil-7(11)-ene-12,8α;14β,6α-diolide(â… -18);19.β-Sitosterol(â… -19);20.Stigmasterol(â… -20);21.3β,Δ⁴-Stigmasten-3-ol(â… -21);22.Daucosterol(â… -22);23.6-O-Acetyl-α-D-glucopyranoside(â… -23);24.Cerotic acid(â… -24).The structure of compounds(â… -1)and(â… -6)were confirmed by X-ray diffraction analysis.Compound(â… -11)was first obtained as natural products.All other compounds were first reported from this plant.The antiviral research on selected constituents from Ligularia atroviolacea was also investigated.The results indicated that compounds(â… -1),(â… -2),(â… -3)and(â… -4)had significant inhibitory effects on the expression of HBsAg secretion from HepG2.2.15 cells.Chapterâ…¡Phytochemieal Investigation and Evaluation of Antiviral Activity of Taraxacum MongolicumHerba Taraxaci,which has a long history as a Traditional Chinese Medicine, has different species as well as rich resources in China.Among which,the most popular species is Taraxacum mongolicum.Its roots,stems and leaves have long been used as folk medicine in China,passed with efficacy of inhibiting bacteria, anti-inflammation,resisting endotoxin,strengthening stomach,normalizing the secretion and discharge of bile,improving lactation,inhibiting tumors and immunological regulation.Previous phytochemical constituents of this genus were concentrated on Taraxacum officinale.In order to find out the active components of Taraxacum mongolicum,which was investigated and 40 compounds were isolated and elucidated,and four of them are new compounds(â…¡-14～Ⅱ-15 andâ…¡-32～Ⅱ-33).The structures of known and new compounds were mainly elucidated by spectral data and shown to be:1.Artemitin(â…¡-1);2.Quercetin(â…¡-2);3.Quercetin-3',4',7-trimethyl ether(â…¡-3);4.Luteolin(â…¡-4);5.Luteolin-7-O-β-D-glucopyranoside(â…¡-5);6.Luteolin-7-O-β-D-galactopyranoside(â…¡-6);7.Genkwanin(â…¡-7);8.Isoetin(â…¡-8);9.3',5,7-Trihydroxy-4'-methoxyflavanone(â…¡-9);10.Genkwanin-4'-O-β-D-lutinoside(â…¡-10);11.Hesperidin(â…¡-11);12.Quercetin-7-O-[β-D-glucopyranosyl(1→6)-β-D-glucopyranoside](â…¡-12);13.Quercetin-3,7-O-β-D-diglucopyranoside(â…¡-13);14.Isoetin-7-O-β-D-glucopyranosyl-2'-O-α-L-arabinopyranoside(â…¡-14);15.Isoetin-7-O-β-D-glucopyranosyl-2'-O-α-D-glucopyranoside(â…¡-15);16.Isoetin-7-O-β-D-glucopyranosyl-2'-O-β-D-xyloypyranoside(â…¡-16);17.Caffeic acid(â…¡-17);18.Furulic acid(â…¡-18);19.3-O-Caffeoylquinic acid(â…¡-19);20.3,5-Di-O-caffeoylquinic acid(â…¡-20);21.3,4-Di-O-caffeoylquinic acid(â…¡-21);22.4,5-Di-O-caffeoylquinic acid(â…¡-22);23.1-Hydroxymethyl-5-hydroxy-phenyl-2-O-β-D-glucopyranoside(â…¡-23); 24.p-Hydroxybenzoic acid(â…¡-24);25.p-Coumaric acid(â…¡-25);26.3,5-Dihydroxybenzoic acid(â…¡-26);27.Gallic acid(â…¡-27);28.Gallicin(â…¡-28);29.Syringic acid(â…¡-29);30.Esculetin(â…¡-30);31.Rufescidride(â…¡-31);32.Mongolicumin A(â…¡-32);33.Mongolicumin B(â…¡-33);34.Isodonsesquitin A(â…¡-34);35.Taraxasteryl acetate(â…¡-35);36.φ-Taraxasteryl acetate(â…¡-36);37.Lupenol acetate(â…¡-37);38.Palmitic acid(â…¡-38);39.Stigmasterol(â…¡-39);40.β-Sitosterol(â…¡-40).It can be seen from the above results,the flavonoids and phenolic acids are the main metabolism of Taraxacum mongolicum.The anti-viral research of constituents from Taraxacum mongolicum was also carried out.Isochlorogenic acids display significant antiviral activity.Chapterâ…¢Studies on Behavior of Chromatographic Separation of Isochlorogenic Acids from Laggera pterodontaLaggera pterodonta is mainly distributed in Africa and southwestern of Asia, especially in Yunnan Province of China.It has anti-flammatory and antibacterial properties.The isochlorogenic acids were the main compounds of Laggera pterodonta.For advanced investigation,the behavior of chromatographic separation of isochlorogenic acids from Laggera pterodonta was studied.In this dissertation,modern technologies such as preparative high performance liquid chromatography and macroporous were employed to purify the three bioactive compounds.Main contents are as follows:1.Flexible analytical methods of effective components in Laggera pterodonta were established in the dissertation.Simultaneous and quick determination methods of three main isochlorogenic acids by HPLC were presented.2.3,4-O-dicaffeoylquinic acid,3,5-O-dicaffeoylquinic acid and 4,5-O-di-caffeoylquinic acid were prepared by preparative high performance liquid chromatography method.A new method was presented that three target compounds could be purified in one step.For 300×100 mm chromatography column,the suitable chromatography conditions were obtained to prepare 3,4-O-dicaffeoylquinic acid,3,5-O-dicaffeoylquinic acid and 4,5-O-dicaffeoylquinic acid in one step,such as the solid phase,composition of mobile phase and flow rate.The chromatography conditions were as follows:C₁₈ (grain size 10μm)as stationary phase;mobile phase was MeOH/H₂O/HAc[27:73: 0.1(v/v/v)],the rate of flow was 45 mL/min and sample capacity was 3.6 g.Under the chromatography stations,the purities of three isochlorogenic acids were above 95%.Chapterâ…£reviewed the development of eremophilane derivatives.