Tubiferic acid, a new 9,10-secocycloartane triterpenoid acid isolated from the myxomycete Tubulifera arachnoidea.

Tubiferic acid (1), a new triterpenoid acid having a 2,6-dimethyl-4,5-dihydroxy-2-hexenoic acid moiety as a side chain, was isolated from field-collected fruit bodies of the myxomycete Tubulifera arachnoidea, and its structure was elucidated by spectral data. Tubiferic acid (1) had the same unique 9,10-secocycloartane carbon skeleton as tubiferal A (2).

Cribrarione C, a naphthoquinone pigment from the myxomycete Cribraria meylanii.

Chemical investigation of field-collected fruit bodies of the myxomycete Cribraria meylanii resulted in the isolation of a naphthoquinone pigment, cribrarione C, and its structure was elucidated by spectral data as 2,5,6,7-tetrahydroxy-1,4-naphthoquinone (1). This compound (1) had been synthesized previously, while it was isolated here for the first time as a natural product, and its NMR and MS data are described in this study.

Bisindole alkaloids from myxomycetes Arcyria denudata and Arcyria obvelata.

A new bisindole sulfate (1) and arcyroxocin B (2) were isolated from wild fruiting bodies of Arcyria denudate, along with three known bisindoles (4-6). Dihydroarcyriacyanin A (3) was obtained from wild fruiting bodies of Arcyria obvelata, along with a known bisindole (7). The structures of these compounds were elucidated on the basis of spectroscopic data, and this is the first report of full characterizations of arcyroxocin B (2) and dihydroarcyriacyanin A (3). Compounds 2, 3, and 6 showed cytotoxicity against Jurkat cells.

New cytotoxic bisindole alkaloids with protein tyrosine kinase inhibitory activity from a myxomycete Lycogala epidendrum.

Two new bisindole alkaloids, 6-hydroxystaurosporinone (1) and 5,6-dihydroxyarcyriaflavin A (2) were isolated from field-collected fruit bodies of a myxomycete Lycogala epidendrum, along with eight known bisindoles (3-10). The structures of these new compounds were determined on the basis of spectroscopic data. Compounds 1 and 2 showed cytotoxicity against HeLa, Jurkat, and vincristine resistant KB/VJ300 cells, and compound 1, particularly, inhibited protein tyrosine kinase activity.

New bisindole alkaloids isolated from Myxomycetes Arcyria cinerea and Lycogala epidendrum.

Two new bisindole alkaloids, named cinereapyrrole A (1) and B (2), were isolated from wild fruit bodies of Arcyria cinerea and three new bisindole alkaloids (3-5) were isolated from wild fruit bodies of Lycogala epidendrum. Seven known bisindoles (6-12) were concomitantly obtained from them. The structures of the new compounds were elucidated by spectral data. Among these bisindole alkaloids, compound 12 showed cytotoxicity against cultured tumor cell lines.

Cribrarione B, a new naphthoquinone pigment from the myxomycete Cribraria cancellata.

Cribrarione B (1), a new naphthoquinone pigment, has been isolated from the myxomycete Cribrariacancellata, and its structure was elucidated as 2,5,8-trihydroxy-6-(1-hydroxyethyl)-[1,4]-naphthoquinone by NMR and mass spectral data.

Isolation of bisindole alkaloids that inhibit the cell cycle from Myxomycetes Arcyria ferruginea and Tubifera casparyi.

From a myxomycete Arcyria ferruginea, dihydroarcyriarubin C (1), a new bisindole alkaloid, has been isolated together with two known bisindoles, arcyriarubin C (2) and arcyriaflavin C (3), and arcyriaflavin C (3) was also isolated from Tubifera casparyi together with arcyriaflavin B (4). Arcyriaflavin C (3) exhibited cell cycle inhibition effect at G1 and G2/M stage at 10 and 100ng/mL, respectively.

Dihydrolindbladiones, three new naphthoquinone pigments from a myxomycete Lindbladia tubulina.

Three new naphthoquinone pigments, 6,7-dimethoxydihydrolindbladione (1), dihydrolindbladione (2), and 6-methoxydihydrolindbladione (3), have been isolated from a myxomycete Lindbladia tubulina, and their structures were elucidated by spectral data. Compound 3 appreciably exhibited a reversal effect of multidrug resistance. Lindbladione (4), the major pigment of this myxomycete, was also isolated from Cribraria intricata.

Cycloanthranilylproline-derived constituents from a myxomycete Fuligo candida.

Cycloanthranilylproline (1) and its derivatives (2--4) were isolated from field-collected fruit-bodies of a myxomycete Fuligo candida and their structures were elucidated by spectral data. Compound 4, which was contained in the water-soluble fraction of the extract of this myxomycete, was unstable and quite susceptible to decarboxylation to yield compound 2, which was a major constituent of the EtOAc-soluble fraction of this extract.

Lindbladione and related naphthoquinone pigments from a myxomycete Lindbladia tubulina.

Lindbladione (1), 7-methoxylindbladione (2), and 6, 7-dimethoxylindbladione (3) have been isolated from a myxomycete Lindbladia tubulina and their structures were elucidated by spectral data.