Atromentin synthesis

The discovery that polyporic acid (11) exhibits antileukemic activity (146) induced the synthesis of numerous analogues (148, 149, 150). The pigment also causes contraction of isolated rabbit ileum suspended in oxygenated Tyrode solution (395). Similarly, atromentin (13) shows significant smooth muscle stimulant activity (638) and proves to be an effective anticoagulant (226, 409). Polyporic acid lacks this latter property completely (409). 

The structures of phlebiarubrone (23) and its dihydroxy derivative (25) were confirmed by synthesis involving methylenation of the potassium salts of polyporic acid (11) and atromentin (13), respectively, with methylene sulphate in the presence of sodium bicarbonate (22,... 

Besides the flavomentins several other mono- and diesters of atromentin (13) have been isolated from fungi (Table 7). The structure of 2-0-acetylatromentin (45) was confirmed by synthesis of the 4, 4"-di-0-methyl ether derivative using the cyclic carbonate (40) and acetic acid (365). 

Asano, M., and S. Huziwara Lichen Pigments of the Pulvinic Acid Series. VI. Synthesis of Atromentinic Acid. J. Pharmac. Soc. Japan 59, 675 (1939). 

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