Article: Total synthesis of 2-methoxy-14-methylpentadecanoic acid and the novel 2-methoxy-14-methylhexadecanoic acid identified in the sponge Agelas dispar

The phospholipid FA composition of the Caribbean sponge Agelas dispar was revisited and 40 different FA were identified. Among these a novel 2-methoxylated FA, namely, the anteiso methyl-branched 2-methoxy-14-methylhexadecanoic acid, was identified together with the recently discovered iso methyl-branched 2-methoxy-14-methylpentadecanoic acid and the normal-chain 2-methoxytetradecanoic acid. The structures of the iso and anteiso methyl-branched 2-methoxylated FA were confirmed by total syntheses, which were accomplished in seven steps and in 45-48% overall yields. Other phospholipid FA identified in A. dispar include the unusual methyl-branched 10,13-dimethyltetradecanoic acid, 3,7,11,15-tetramethylhexadecanoic (phytanic) acid, and the 11-methyloctadecanoic acid. In addition, the delta5,9 FA (5Z,9Z)-15-methyl-5,9-hexadecadienoic acid and (5Z,9Z)-5,9-octadecadienoic acid were characterized. These findings establish alternative FA biosynthetic possibilities for these marine organisms.

Citing Articles

Identification of novel alpha-methoxylated phospholipid fatty acids in the Caribbean sponge Erylus goffrilleri.

Carballeira N, Oyola D, Vicente J, Rodriguez A Lipids. 2007; 42(11):1047-53.

PMID: 17710462 DOI: 10.1007/s11745-007-3110-0.

References

1.

Yano I, Furukawa Y, Kusunose M . 2-hydroxy fatty acid-containing phospholipid of Arthrobacter simplex. Biochim Biophys Acta. 1970; 210(1):105-15. DOI: 10.1016/0005-2760(70)90066-4. View

2.

Takagi T, Itabashi Y, Aso S . Fatty acids and fatty alcohols of wax esters in the orange roughy: specific textures of minor polyunsaturated and branched-chain components. Lipids. 1985; 20(10):675-9. DOI: 10.1007/BF02534386. View

3.

Carballeira N, Maldonado L, Porras B . Isoprenoid fatty acids from marine sponges. Are sponges selective?. Lipids. 1987; 22(10):767-9. DOI: 10.1007/BF02533980. View

4.

Carballeira N, Alicea J . The first naturally occurring alpha-methoxylated branched-chain fatty acids from the phospholipids of Amphimedon complanata. Lipids. 2001; 36(1):83-7. DOI: 10.1007/s11745-001-0672-1. View

5.

Carballeira N, Pagan M . New methoxylated fatty acids from the Caribbean sponge Callyspongia fallax. J Nat Prod. 2001; 64(5):620-3. DOI: 10.1021/np000537q. View

6.

Ayanoglu E, Popov S, Kornprobst J, Aboud-Bichara A, Djerassi C . Phospholipid studies of marine organisms: V(1) new α-methoxy acids fromHigginsia tethyoides. Lipids. 2016; 18(11):830-6. DOI: 10.1007/BF02534643. View

7.

Privett O, Dougherty K, Erdahl W, Stolyhwo A . Studies on the lipid composition of developing soybeans. J Am Oil Chem Soc. 1973; 50(12):516-20. DOI: 10.1007/BF02640523. View

8.

Cafieri F, Fattorusso E, Taglialatela-Scafati O . Novel bromopyrrole alkaloids from the sponge Agelas dispar. J Nat Prod. 1998; 61(1):122-5. DOI: 10.1021/np970323h. View

9.

Dunkelblum E, Tan S, Silk P . Double-bond location in monounsaturated fatty acids by dimethyl disulfide derivatization and mass spectrometry: Application to analysis of fatty acids in pheromone glands of four lepidoptera. J Chem Ecol. 2013; 11(3):265-77. DOI: 10.1007/BF01411414. View

10.

Cafieri F, Fattorusso E, Taglialatela-Scafati O . Novel betaines from the marine sponge Agelas dispar. J Nat Prod. 1998; 61(9):1171-3. DOI: 10.1021/np980157t. View

11.

Carballeira N . New advances in the chemistry of methoxylated lipids. Prog Lipid Res. 2002; 41(6):437-56. DOI: 10.1016/s0163-7827(02)00005-x. View

12.

Yano I, Furukawa Y, Kusunose M . Occurrence of alpha-hydroxy fatty acids in Actinomycetales. FEBS Lett. 1969; 4(2):96-98. DOI: 10.1016/0014-5793(69)80205-x. View

Total Synthesis of 2-methoxy-14-methylpentadecanoic Acid and the Novel 2-methoxy-14-methylhexadecanoic Acid Identified in the Sponge Agelas Dispar