Phlegmacin

There is only a small number of reports in the literature about the cytotoxicity of dimeric hydroxyanthracenones Toroasol I (28) and II (29) inhibit an in-vitro KB cell line with an ED50 of 1.7 and 5.5 pg/ml respectively occidentalol I (25a), occidentalol II (25b) and phlegmacines (21) have been patented as cytotoxic agents by Taisho pharmaceutical Co.[74] however, phlegmacines Aj and B, did not show selective toxicity. 

It can be summarised that the different methods of kinetic resolution and the synthetic correlations have led to the determination of stereochemistry at the biaryl linkage of atrivirin and flavomannin derivatives. Because the position and shape of the CD couplet around 275 nm is not much influenced by substituents present in the two halves of the dimers (refs. 3, 23), several other pigments can now be correlated. It will however need the development of further methods to elucidate the stereochemistry of the phlegmacin group and to determine the configuration of the chiral centers located in the alicyclic rings of the dimers. 

Table 32. H-N.m.r. Data for Atrochrysone (321), Atrovirin-B (336), FDM (348), Pseudo-phlegmacin-A (367), Phlegmacin-Bi (371), Tricolorin-A (377), Cortinarin (381), and Rufooli-vacin (382) (S values, with TMS as internal standard)...

Phlegmacin (371) and its methyl ether (372) have proved of value in the taxonomy of Phlegmacium where they are each representative of two different groups of closely related fungi 515, 617). As in pre-... 

It is interesting to note from Table 35 that phlegmacin (371) is produced by the various species of Cortinarius with differing degrees... 

Besl and Bresinsky 86) discovered in Leucopaxillus tricolor (Tri-cholomataceae), besides endocrocin (303), two yellow pigments which bore superficial resemblances to asperflavin (329) and to phlegmacin (371). Closer chemical investigations, however, have revealed that these substances represent a new type of dimeric pre-anthraquinone 94,515). 

---