Amijitrienol and 14-Deoxyisoamijiol, Two New Diterpenoids from the Brown Seaweed Dictyota linearis

Abstract

The structures of amijitrienol and 14-deoxyisoamijiol, two new diterpenoids isolated from the brown seaweed Dictyota linearis, have been established as 1 and 2 on the basis of spectral and chemical evidence.

Inhibition of mammal Na+K+‐ATPase by diterpenes extracted from the Brazilian brown alga Dictyota cervicornis

“…The dolastane diterpenes (1) and (2) are known compounds previously isolated from D. divaricata and D. linearis (Sun et al, 1981;Crew et al, 1982) and an unidentified Dictyota from the Canary Islands (Gonzalez et al, 1983). Several of these diterpenoids showed antimicrobial activity against Bacillus subtilis and Penicillium crustosum (Ochi et al, 1980), Staphylococcus aureus and Mucor mucedo (Ochi et al, 1986) and as cytotoxic compounds (Crew et al, 1982). Although some diterpenes have been isolated from Dictyota spp., it was shown that two of them are inhibitors of Na + K + -ATPase.…”

Asymmetric Total Synthesis of (−)‐Indicol by a Carbene Cyclization–Cycloaddition Cascade Strategy

“…The dolastanes have been reported to show a wide range of biological activities, including cytotoxicity, histamine antagonism, antifungal, and antibiotic effects. [18][19][20][21] Interestingly, they are structural relatives of the potent antibiotic, guanacastepene A. [22] Several dolastanes, such as isoamijiol (4), dolastatrienol 6, and 14-deoxyisoamijiol, have been successfully synthesized as racemates and as the unnatural antipodes.…”

“…The dolastanes are tricyclic natural products isolated from the same algal species, and are characterized by the presence of an additional cyclopentane ring C fused to the AB rings of the secodolastanes. The dolastanes have been reported to show a wide range of biological activities, including cytotoxicity, histamine antagonism, antifungal, and antibiotic effects 18–21. Interestingly, they are structural relatives of the potent antibiotic, guanacastepene A 22…”

Chemical Composition of Diterpenes from the Brown Alga Canistrocarpus cervicornis (Dictyotaceae, Phaeophyceae)

“…Many of these diterpenes were isolated from other populations of this species and also from populations of C. crispatus (as Dictyota crispata) from Brazil [12]. In this context, the populations named Dictyota divaricata and D. linearis from the Caribbean Sea [13,14] and Japan [15][16][17][18], D. dichotoma [19][20][21][22] and D. indica from Pakistan [23][24], D. furcellata from Australia [25] and Dictyota sp. from the Canary Islands [26] could be considered as C. cervicornis.…”