Aplysina fistularis

One of the first biosynthetic investigations undertaken in the Djerassi laboratory dealt with the sponge Aplysina fistularis. This sponge contains sterols with side-chain alkylations at C-24 and C-26, the aplysterols [37], The biosynthesis of these unconventional sterols was shown (Scheme 7) to proceed by a conversion of desmosterol (34) to epicodisterol (51) [but not its C-24 epimer, codisterol (52)] followed by methylation to 25(27)-dehydroaplysterol (53). Sterol... 

Gulavita, N.K. Pranponi, S.A. Wright, A.E. Garay, M. Sills, M.A. (1995) Aplysillin A, athrombin receptor antagonist from the marine sponge Aplysina fistularis fidva. J. Nat. Prod., 58, 954-7. 

Aplysillin A (527), with unknown double bond geometries was isolated from Aplysina fistularis and is a weak thrombin receptor antagonist [442]. 

A dibromotyrosin-derived metabolite present at 1.0% sponge dry weight, aerothionin (148), from Aplysina fistularis completely inhibits fish feeding when assayed in a 1.0% food pellet [115]. 

Fig. 6.1 Aplysina fistularis, a sponge rich in bromophenols and bromotyrosines (Photo F. J. Schmitz)...

Gulavita NK, Pomponi SA, Wright AE, Garay M, Sills MA (1995) Aplysillin A, a Thombin Receptor Antagonist from the Marine Sponge Aplysina fistularis fulva. J Nat Prod 58 954... 

Compagnone RS, Avila R, Suarez AI, Abrams OV, Rangel HR, Arvelo F, Pina IC, Merentes E (1999) ll-Deoxyfistularin-3, a New Cytotoxic Metabolite from the Caribbean Sponge Aplysina fistularis insularis. J Nat Prod 62 1443... 

Carney JR, Rinehart KL (1995) Biosynthesis of Brominated Tyrosine Metabolites by Aplysina fistularis. J Nat Prod 58 971... 

Thompson JE, Barrow KD, Faulkner DJ (1983) Localization of Two Brominated Metabolites, Aerothionin and Homoaerothionin, in Spherulous Cells of the Marine Sponge Aplysina fistularis (= Verongia thiona). Acta Zool 64 199... 

Thompson, J. E., Barrows, K. D., and Faulkner, D. J., Localization of two brominated metabolites, aerothionin and homoaerothionin, in spherulous cells of the marine sponge Aplysina fistularis (= Verongia thiona), Acta Zool., 64, 199, 1983. 

Thompson, J. E., Exudation of biologically-active metabolites in the sponge Aplysina fistularis. I. Biological evidence, Mar. Biol., 88, 23, 1985. 

Tymiak, A. A., and Rinehart, K. L., Jr., Biosynthesis of dibromotyrosine-derived antimicrobial compounds by the marine sponge Aplysina fistularis (Verongia aurea), J. Am. Chem. Soc., 103, 6763, 1981. 

The fantastic stmctural diversity of the natural brominated tyrosines has led to equally ingenious biosynthesis proposals, but only a few definitive labeling studies have been described. The early study by Tymiak and Rinehart on the biosynthesis of dibromotyrosine metabolites by the sponge Aplysina fistularis supports the incorporation of both phenylalanine (127) and tyrosine (128) into dienone 133 and dibromohomogentisamide (134) (Scheme 19.6) [120]. Metabolites 131,132, 135, and 136 were also identified along with 133 and 134 in this study, which utilized... 

Walkup, R.D., G.C. Jamieson, M.R. Ratcliff, and C. Djerassi Phospholipid Studies of Marine Organisms 2. Phospholipids, Phospholipid-Bound Fatty Acids and Free Sterols of the Sponge Aplysina fistularis (Pallas) Forma fulva (Pallas) (= Ve-rongia thiona). Isolation and Structure Elucidation of Unprecedented Branched Fatty Acids. Lipids 16, 631 (1981). 

Aplysina fistularis ioimdi. fulva Gopichand and Schmitz, 1979 Rogers et al. 2005... 

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