Lamellaria Lamellarins

Another interesting investigation of the use of microwave irradiation for the synthesis of alkaloids was recently reported by M. Alvarez et al., where the authors investigated a modular total synthesis of Lamellarin D [93]. After 20 years of the first isolation of this compound from the marine prosobranch mollusk Lamellaria sp, this family currently comprises more than 30 members, isolated from various natural sources. With its recent identification as... 

The lamellarins constitute an important group of natural products isolated from marine invertebrates such as sponges, molluscs and tunicates with structures without precedents in natural or synthetic compounds. They are characterized for possessing important biological activities. The aim of this review is to provide an overview of the work published since the isolation of the first group of lamellarins <85JA5492> from the marine prosobranch mollusc Lamellaria sp, imtil the beginning of 2004. 

Investigation of animals from the marine enviroiunent has thrown up an intriguing variety of poly-heterocyclic products (sometimes called sea alkaloids) five representatives are variolin B (sponge, Kirkpatrickia varialosa), lamellarin B (mollusc, Lamellaria sp.), ascididemine (mnicate, Didemnum sp.), wakayin ° (ascidian, Clavelina sp.) and dendrodoine" (tunicate, Dendroda grossular), a rare natural example of a multi-heteroatom compound. 

The L. are a class of marine alkaloids with the S-oxa-6b-aza-dibenzo[a,i]-9-fluoren-6-one skeleton. Since the first isolation of lamellarins A-D in 1985 from a prosobranch mollusc of the genus Lamellaria, more... 

The intertidal limpet Collisella limatula contains limatulone (914) which inhibits fish and crab predation (600b). Food pellets containing 914 at levels of 0.05% dry weight or more induced regurgitation in the intertidal fish Gibbonsia elegans, a known limped predator. The marine prosobranch mollusc, Lamellaria sp. furnished four aromatic metabolites, lamellarins A-D (915-918) (600 c). At concentrations of 19 pg/mL, 918 caused a 78% inhibition of cell division in the fertilized sea urchin egg assay while 917 caused 15% inhibition and 915 as well as 916 were inactive. 

The term lamellarin derives from that of a prosobranch mollusk (Mesogastropoda) of the genus Lamellaria that feeds on ascidians and incorporates some metabolites to protect itself from predators, and it is now accepted that most lamellarins are produced by the ascidian and some of... 

The structures of polycitone A (280) and B (281) and polycitrin A (282) and B (283) were close to the lamellarins isolated from the mollusk Lamellaria sp. (169) and an ascidian of the genus Didemnum (170,171). Lammellarins are not included in this review because of the absence of a halogen in their structures. A possible biogenetic... 

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