| biscopyran, a phytotoxic hexasubstituted pyranopyran produced by biscogniauxia mediterranea, a fungus pathogen of cork oak. | a new phytotoxic hexasubstituted pyranopyran, biscopyran (3), was isolated together with phenylacetic acid (2) and previously isolated 5-methylmellein (1) from the liquid culture filtrates of biscogniauxiamediterranea, a major fungal pathogen involved in oak decline in sardinia. biscopyran was characterized by spectroscopic methods as a new (z)-2-methoxy-1-[7-((z)-2-methoxybut-2-enoyl)-3,4,5,6-tetramethyl-2h,7h-pyrano[2,3-b]pyran-2-yl]but-2-en-1-one. biscopyran assayed at 0.26-0.026 mm concentra ... | 2005 | 15844950 |