Synthesis of 8-hydroxy-6-methoxy-3-pentyl-1H-isochromen-1-one from Tessmannia densiflora

Intramolecular transesterification of depsides yields fluorescent 1H-isochromen-1-ones: Application as a chemical probe for lichen determination

“…-tri-substituted 1H-Isochromen-1-ones: glomelline (8) (Huneck and Follmann, 1973), 4-O-methylolivetonide (9) (Asai et al, 2017;Saeed, 2011), insignine (10) (Elix et al, 1996) and olivetonide (11) (Huneck et al, 1970;Kaji et al, 1986;Sanchez, 1994), fluorescent at 365nm (F) in basic conditions. These heterocycles were obtained by rearrangement of the -keto-ester moiety of the ring A.…”

Isocoumarins and 3,4-dihydroisocoumarins, amazing natural products: a review

“…The most common drug prescribed for malaria patients is chloroquine, but some derivatives of 3,4-dihydroisocoumarin, mullein 37a-37d, produced by Botryosphaeria rhodina, an endophytic fungus, show effective antimalarial activity (Figure 9). 47 Some isocoumarin derivatives, 8-hydroxy-6-methoxy-3-pentyl-1H-isochromen-1-one 38a-38b 48,49 and halorosellins 39, 50 isolated from the bark and stem of Tessmannia densiflora and Halorosellinia oceanica, respectively, also showed antimalarial activity ( Figure 9). Ceratocystis fimbriata, a fungus, is a source of isocoumarins 40a-40d that are known for their phytotoxic activity on leaves of coffee trees, and also they are responsible for fruit withering with trunk canker in adult coffee trees ( Figure 10).…”