Dictyota linearis

Ochi M, Watanabe M, Miura I, Taniguchi M, Tokoroyama T (1980) Amijiol, isoamijiol, and 14-deoxyamijiol, three new diterpenoids from the brown seaweed Dictyota linearis. Chem Lett 10 1229-1232... 

Brown algae are rich in diterpenoids, which can be classified into three groups, namely xenicanes, extended sesquiterpenes, and dolabellanes, which are represented by dictyotadial (121) from Dictyota crenulata, spatol (122) from Spatoglossum schmit-tii, and amijidictyol (123) from Dictyota linearis, respectively. 

Isoamijiol (159 Scheme 52), a linear 5,7,6-ring-fused member of the dolastane group of diterpenes, is the principal secondary metabolite in the brown seaweed Dictyota linearis. In the course of the synthesis of (159), Pattenden also used a photocycloaddition-fragmentation sequence. Treatment of (157) with HF as mentioned above yields the hydroazulenone portion (158) of (159), which then was elaborated to isoamijiol. This is the first example of a C=C bond and an Si—-O bond being used as push-i)uU partners in a fragmentation. 

Dictyota dichotoma and Dictyota linearis [94], The diterpenes isopachydictyolal from Dictyota dichotoma, and 4a-acetyldictyodial, Fig. (8) from Dictyota linearis are new natural products which showed potent antiviral activity against HSV-1 using Vero cells as hosts. 

A concise synthesis of the dolastane metabolite, isoamijiol (61), found in the brown seaweed Dictyota linearis, starts from the enamine (55) and uses only seven C-C bond forming reactions, four of... 

Metabolites of various algae and eorals also inelude dolastadienes and -trienes, exemplified by l(15),8-dolastadiene-4p,14p-diol (amijiol), its isomer isoamijiol, and l(15),7,9-dolastatrien-14p-ol from brown algae Dictyota linearis and D. cervi-cornis, as well as l(15),17-dolastadiene-3a,4p-diol from the soft coral Clavularia inflata. 

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