Laurencia luzonensis

An Okinawan collection of Laurencia luzonensis has yielded five new sesquiterpenes, luzonenone (339), luzofuran (340), 3,4-epoxypalisadin B (341), 1,2-dehydro-3,4-epoxypalisadin B (342), and 15-hydroxypalisadin A (343 (558). In addition, the relative stereochemistry of luzonensol (321) (vide supra) (549) was assigned by conversion to the known palisadin B (P) (7). The novel fused bisabo-lene aldingenins A (344), B (345), C (346), and D (347) were isolated from Laurencia aldingensis (559, 560). The interesting chlorotriol 348 was found in a Turkish Laurencia obtusa (561). 

Kuniyoshi M, Marma MS, Higa T, Bemardinelli G, Jefford CW (2001) New Bromoter-penes from the Red Alga Laurencia luzonensis. J Nat Prod 64 696... 

Kuniyoshi M, Wahome PG, Miono T, Hashimoto T, Yokoyama M, Shrestha KL, Higa T (2005) Terpenoids from Laurencia luzonensis. J Nat Prod 68 1314... 

Two related brominated diterpenes belonging to dac-tylomelane (diprenylpyronane) series, luzodiol and laurendecumtriol, have been identified in Laurencia luzonensis (Okinawa, Japan) and I. decumbens (South China Sea), respectively. Both are brominated on C-10, as displayed in Figure 13.15. Luzodiol is accompanied by a dozen brominated sesquiterpenes all with the carbon skeleton of snyderane (Kuniyoshi et al., 2005). 

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