Structures, biogenesis, and biological activities of pyrano[4,3-c]isochromen-4-one derivatives from the Fungus Phellinus igniarius.

Further chemical investigation of the Chinese medicinal fungus Phellinus igniarius has resulted in the isolation and structural elucidation of three pyrano[4,3-c]isochromen-4-one derivatives, phelligridins H (1), I (2), and J (3), together with the known compounds davallialactone (4), scopolin, nebularine, uridine, trehalose, glucitol, and ethyl glucoside. The structures of 1-3 were elucidated by spectroscopic methods. Phelligridins H (1) and I (2) possess unprecedented carbon skeletons, and phelligridin J (3) is an oxidative derivative of the co-occurring phelligridin A.

Phelligridimer A, a highly oxygenated and unsaturated 26-membered macrocyclic metabolite with antioxidant activity from the fungus Phellinus igniarius.

[structure: see text] A highly oxygenated and unsaturated 26-membered macrocyclic metabolite, phelligridimer A (1), has been isolated from the Chinese medicinal fungus Phellinus igniarius. Its structure was elucidated by spectroscopic methods. A possible biogenesis of 1 mediated by the fungal metabolite hispidin was postulated.

A unique highly oxygenated pyrano[4,3-c][2]benzopyran-1,6-dione derivative with antioxidant and cytotoxic activities from the fungus Phellinus igniarius.

[structure: see text] A unique pyrano[4,3-c][2]benzopyran-1,6-dione derivative with an unprecedented carbon skeleton, phelligridin G (1), has been isolated from the fruiting body of the fungus Phellinus igniarius. Its structure was elucidated by detailed spectroscopic analysis. A possible biogenetic origin of 1 mediated by the fungal metabolite precursor 4-hydroxy-6-methyl-2-pyrone was postulated.

[Studies on chemical constitutes of Phellinus igniarius].

Objective: To study the chemical constituents of Phellinus igniarius.

Method: Compounds were isolated by nomal phasc sillica gel and Al2O3 chromatography and reverse phase HPLC. Their structures were elucidated by spectroscopic methods including IR, MS and NMR.

Furostanol oligoglycosides from Asparagus cochinchinensis.

Three new furostanol oligoglycosides, named aspacochioside A (1), B (2) and C (3), together with the known compound 3-O-[(alpha-L-rhamnopyranosyl-(1 --> 4))(beta-D-glucopyranosyl)]-26-O[beta-D-glucopyranosyl]-(25S)-5beta-spirostane-3beta-ol were isolated from the roots of Asparagus cochinchinensis. Their structures were elucidated by spectroscopic techniques (IR, HR-ESIMS, ESIMS/MS, ID and 2D NMR) and chemical methods as 3-O-[(alpha-L-rhamnopyranosyl-(1 --> 4))(beta-D-glucopyranosyl)]-26-O-[beta-D-glucopyranosyl]-(25S)-5beta-furostane-3beta,22alpha,26-triol (1), 3-O-[(alpha-L-rhamnopyranosyl-(1 --> 4))(beta-D-glucopyranosyl)]-26-O-[beta-D-glucopyranosyl]-22alpha-methoxy-(25S)-5beta-furostane-3beta,26-diol (2), and 3-O-[(alpha-L-rhamnopyranosyl-(1 --> 4))(beta-D-glucopyranosyl)]-26-O-[beta-D-glucopyranosyl]-(25S)-5beta-furost-20(22)-en-3beta,26-diol (3).

Chemical constituents of the rhizomes of Coeloglossum viride var. bracteatum.

Seven new compounds, named coelovirins A-G (1-7), along with fourteen known constituents were isolated from the rhizomes of Coeloglossom viride var. bracteatum (Orchidaceae). On the basis of chemical and spectroscopic methods, including 2D-NMR techniques, the structures of new compounds were elucidated as 1-(4-beta-D-glucopyranosyloxybenzyl)-(2R,3S)-2-isobutyltartrate (1), 4-(4-beta-glucopyranosyloxybenzyl)-(2R,3S)-2-isobutyltartrate (2), 1-(4-beta-D-glucopyranosyloxybenzyl)-(2R,3S)-2-beta-D-glucopyranosyl-2-isobutyltartrate (3), 4-(4-beta-D-glucopyranosyloxybenzyl)-(2R,3S)-2-beta-D-glucopyranosyl-2-isobutyltartrate (4), (2R,3S)-2-beta-D-glucopyranosyl-2-isobutyltartaric acid (5), bis(4-beta-D-glucopyranosyloxybenzyl)-(2R,3S)-2-[beta-D-glucopyranosyl-(1 --> 4)-beta-D-glucopyranosyl]-2-isobutyltartrate (6) and bis(4-beta-D-glucopyranosyloxybenzyl)-(2R)-2-[beta-D-glucopyranosyl-(1 --> 4)-beta-D-glucopyranosyl]-2-isobutylmalate (7).

Chemical constituents of Pyrrosia petiolosa.

The new flavone diglycoside 7-O-[6-O-(alpha-L-arabifuranosyl)-beta-D-glucopyranosyl]-gossypetin, named as pyrropetioside, along with 13 known compounds (including 3 artifacts) have been isolated from Pyrrosia petiolosa. Their structures have been elucidated by means of chemical and spectroscopic methods including IR, MS, 1D and 2D NMR techniques.