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Chemical constituents of Ligularia hookeri (Asteraceae) collected in Yunnan and Sichuan Provinces in China were examined for the first time. Seven furanoeremophilanes, five of which were new, as well as known bisabolane- and eudesmane-type sesquiterpenoids, were isolated. Spectroscopic evidence indicates that the previously reported 3β-(2'-methylpropenoyloxy)furanoeremophilan-15,6β-olide should be revised to 3β-(2'-methylpropenoyloxy)furanoeremophilan-15,6α-olide.

The terpenoid constituents of Ligularia virgaurea (30 samples), Ligularia pleurocaulis (8 samples), Ligularia dictyoneura (8 samples), Ligularia brassicoides (5 samples), Ligularia lingiana (1 sample), and Ligularia liatroides (1 sample)(all belonging to section Senecillis of Ligularia, Asteraceae and collected in Yunnan, Sichuan, Qinghai, and Gansu provinces, China), from which 220 compounds were isolated, including 113 novel ones, are reviewed. Five chemotypes were identified in L. virgaurea based on their chemical constituents, while three clades were detected from the base sequences. Although intra-specific diversity was found in L. virgaurea, more samples were needed of other species in order to reach a definite conclusion. Inter-specific diversity was also examined in section Senecillis but was restricted due to the scarcity of samples. Synthetic studies on chiral natural products to determine their absolute configurations, especially those of riccardiphenols A and B as well as crispatanolide, which were all isolated from the liverwort, are briefly reviewed.

A chemical analysis of 30 samples of Ligularia virgaurea (Asteraceae) collected in Sichuan province and its adjacent territories in China was reviewed. These samples afforded 146 compounds, 73 of which were novel, and the chemical constituents were classified into 8 categories: (1) simple eremophilanes (without ring C) and eudesmanes including nor-derivatives, (2) furanoeremophilanes and lactones with a 1(10)-saturated bond, (3) furanoeremophilanes and lactones with a 1(10)-unsaturated bond, 1,10-epoxide, or 10-ol, (4) furanoeremophilanes and lactones with 1(10)-en-2-one, 1(10)-en-2-ol, or 1-en-3-one, (5) furanoeremophilanes and lactones with 1(10)-en-9-one, 1(10)-en-9-ol, or 1,10-epoxy-9-one, (6) cacalol and their derivatives, (7) bakkanes and their derivatives, and (8) others, as shown in Tables 1-7. In these studies, five chemotypes were identified in addition to three clades from the DNA sequences of L. virgaurea. The structural determination of some compounds was also discussed and a comment on how to express the real structure was proposed, particularly for spiro compounds.

Eight new hydroperoxides and a new enone of germacrane-type sesquiterpenoids were isolated from the aerial parts of eight different samples of Eupatorium heterophyllum DC. (Asteraceae) collected in P.R. China. The structures were determined based on spectroscopic analyses. Seven of the eight samples produced hiyodorilactone A as a major constituent, while one afforded neither hiyodorilactone nor hydroperoxide. The results indicated the presence of diversity within this species.

Four new germacrane-type sesquiterpenoids with unsaturated acids as esters at the 8-position, two chlorine atom-containing lactones, 2alpha-acetoxyepitulipinolide, and 12 previously known compounds have been isolated from the MeOH extract of Eupatorium glehni (Compositae) and their structures have been determined on the basis of spectral data analyses.

Nitrogen-containing compounds have been subjected to electrochemical oxidation with Et3N-3HF as an electrolyte. Caffeine afforded 8-fluorocaffeine as a sole product in 40.3% yield. Guanosine tetraacetate and uridine triacetate gave the fluorinated compounds in 17.5 and 4.6% yields, rspectively. Similar electrochemical oxidation of caffeine with methanol, KCl, or KCN afforded 8-methoxycaffeine, 8-chlorocaffeine, or 8-cyanocaffeine, respectively.

Eight new sacculatane-type diterpenoids, named 12-deoxy-1β, 11α-dihydroxy-sacculatanolide (1), 11α-hydroxysacculatanolide (2), pellianolactones A, B, (3, 4), 1β, 11α-dihydroxysacculatanolide (5), 1β-hydroxysacculatal (6), 1β-hydroxy-isosacculatal (7), and 1β-hydroxysacculatanolide (8), have been isolated from the liverwort Pellia endiviifolia.

Three novel polyacetylene triglycerides, named lycogarides A-C (1-3), have been isolated from the Myxomycetes Lycogala epidendrum. Their relative structures have been established by a combination of two-dimension NMR spectroscopy and chemical degradation. The absolute structures of compounds 1 and 2 were deduced from the modified Mosher's and dibenzoate exiton chirality methods of their derivatives.

Three novel azaphilone derivatives, daldinins A∼C, have been isolated from the fungus (Ascomycetes) Daldinia concentrica. Their structures including the absolute configuration have been established by a combination of high resolution NMR and CD spectra, X-ray crystallographic analysis, and chemical degradation.

Fusicorrugatol, a new fusicoccane-type diterpene alcohol, has been isolated from the Venezuelan liverwort Plagiochila corrugata and its structure determined on the basis of spectroscopic evidence and X-ray crystallography.

Two novel bis(bibenzyls) named paleatins A (1) and B (2) have been isolated from the liverwort, Marchantia paleacea var. diptera. Their structures have been establishied by a combination of high-resolution NMR spectra and chemical degradation. A total synthesis of paleatin A has been accomplished in ten steps.

A novel binaphthyl (1) and three novel benzophenone derivatives (2-4) have been isolated from the fungus (Ascomycetes) Daldinia concentrica. Their structures have been established by a combination of high resolution NMR spectra, X-ray crystallographic analysis and chemical degradation. Compounds 2 and 3 possess plant-growth inhibitory activity.

Five new diarylheptanoids, yashabushidiol A and B, yashabushiketodiol A and B, and yashabushitriol, have been isolated from the male flowers of Alnus sieboldiana MATSUM. and their absolute structures determined by spectral methods and chemical transformations to known yashabushiketol and dihydroyashabushiketol.

Epoxidation of alnus-5 (10)-en-3β-yl acetate (3) with m-chloroperbenzoic acid gave a 5α, 10α-epoxide (4), which was subjected to the BF3·OEt2-catalyzed backbone rearrangement to afford multiflora-5, 8-dien-3β-yl acetate (6) as a main product. Hydrogenation of the diene (6) followed by hydrolysis gave isomultiflorenol (1a).

The title compound has been reductively carboxylated under the Birch reduction conditions. The resulting keto esters are assigned to cis and trans fused hydrindanones by transofrmations into 1, 5-dimethyl-4, 5, 6, 7, 8, 9-hexahydroindan-4-ones.