Petrosia

Establishment of the dietary or symbiotic origin of sterols could be a difficult task, unless the tracer sterol has an unusual structure and restricted occurrence. There is little doubt, for example, that petrosterol (59) found in the nudibranch Peltodoris atromaculata [112] arises from predation of the mollusc on the sponge Petrosia ficiformis, from which the sterol was first isolated [113]. However, the origin of gorgosterol (60) in Tridacna species has not yet been established [114] despite its unusual structure. 

Guerriero, A. lM>itus, C. Laurent, D. D Ambrosio, M. Pietra, F. (1998) A2d6quynol A, the first clearly defined, C-branched pmlyacetylaie and the analogue aztagiynol B. Isolation from the tropical marine sponge Petrosia sp. Tetrahedron Lett., 39,6395-8. 

Ambartsumian, T. G., Adamian, S. Y., Petrosia, L. S., and Simonian, A. L. (1992). Incorporation of water-soluble enzymes glucose-oxidase and urate oxidase into phosphatidylcholine liposomes. Biol. Membr, 5, 1878-87. 

Three antiviral sterol disulfate orthoesters, orthoesterol disulfates A-C (586-588) were isolated from Petrosia weinbergi and their structures were determined by spectral data elucidation [473]. 

Castiello, D., Cimino, G., De Rosa, S., De Stefano, S., and Sondo, G., High molecular weight polyacetylenes from the nudibranch Peltodoris atromaculata and the sponge Petrosia ficiformis, Tetrahedron Lett., 21, 5047, 1980. 

Xestospon a exigua (Kirkpatrick) Genus Petrosia Vosmaer Milne Bay, Papua New Guinea 15, 16 [43]... 

Linear polyacetylenes are found frequently in marine sponges of the order Haplosclerida (11). Although the chain lengths vary from Ci4 to C49, likely they are to be derived from Cie fatty acids. Polyacetylenes show a wide range of bioactivities, including antimicrobial, cytotoxic, antiviral, and enzyme inhibitory. Corticatic acid A (8), which is a C31 polyacetylene carboxyhc acid isolated from Petrosia corticata, is not only antimicrobial, but also it inhibits geranylgeranyltransferase I (12). 

Other biogenetically distinct cyclopropane side chain substitution patterns are typified by the sponge sterols calysterol (25) isolated from Calyx nicaensis, and petrosterol (19) found in Petrosia. Unlike the biosynthesis of gorgosterol-type (17)... 

Two novel alkaloids named manadomanzamines A and B were isolated from the Indonesian sponge Acanthostrongylophom spp. [58]. The compounds exhibited activities against HIV-1 and AIDS-opportunistic fungal infections. Oral and intravenous pharmacokinetic studies indicated that the compounds have low metabolic clearance, a reasonably long pharmacokinetic half-life, which supports the value of these compounds as potential leads for further preclinical assessment and possible development [59]. Another marine sponge, Petrosia similis, afforded two compormds belonging to bis-quinolizidine alkaloids, namely petrosin and petrosin A [60]. Cell assays indicated that these compounds inhibited the early steps of HIV replication. In the extracellular HIV-1 RT inhibition assay, the compounds inhibited HIV-1 RT. 

The South Pacific and Caribbean sponges Amphimedon sp. and Petrosia sp. are the source of fused aromatic alkaloids sharing a common carbon skeleton, amphimedine (115), isolated by Schmitz and coworkers (89), and petrosamine (116), reported by Faulkner s group (90). The structure of amphimedine was secured by two-dimensional NMR techniques, in particular the natural abundance 13C- 3C coupling correlation experiment, INADEQUATE. Amphimedine was isolated by Soxhlet extraction of the freeze-dried sponge with chloroform. Silica gel and... 

Pichiafurans A-C (98—100) and pichiacins A (101) and B (102) have been characterized from the yeast Pichia membranifaciens, which was obtained from the Korean marine sponge Petrosia sp. So far, no marine isolates of the genus Pichia had been described, and this yeast had not been studied with regard to its secondary metabolite chemistry. Compounds 98—100 are friryl ethers with 2-phenylethanol, while 101 and 102 are esters consisting of 2-phenylethanol and short-chain w-hydroxy acids. 

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