Depsidones

Depsidones of the orcinol type are characterized by UV maxima in the range of 208-224 (log 8 4.46), 250-270 (log8 4.13), and 300-333nm 

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Depsidones from Lobaria pulmonaria and their chemotaxonomic importance. Biochem. Syst. Ecol. 22 583-586. 

Fig. 3.32 Acarospora gobiensis, a Central Asian lichen that contains the novel brominated depsidones, acarogobiens A and B (2146 and 2147) (Photo T. Rezanka)...

Like depsides and depsidones, most chlorinated xanthones are found in lichens, and more than 50 such compounds were described in the first survey (/ ). The lichen... 

Mahandru MM, Tajbakhsh A (1983) Fulgoicin, a New Depsidone from the Lichen Fulgensia fulgida (Nyl.) Szat. J Chem Soc Perkin Trans 1 2249... 

Birkbeck AA, Sargent MV, Elix JA (1990) The Structures of the Lichen Depsidones Fulgidin and Isofulgidin. Aust J Chem 43 419... 

Sala T, Sargent MV (1981) Depsidone Synthesis. Part 16. Benzophenone - Grisa-3 ,5 -diene-2 ,3-dione - Depsidone Interconversion A New Theory of Depsidone Biosynthesis. J Chem Soc Perkin Trans 1 855... 

Rezanka T, Guschina IA (1999) Brominated Depsidones from Acarospora gobiensis, a Lichen of Central Asia. J Nat Prod 62 1675... 

Of the more than 20,000 known species of lichens, only a few have been analyzed and identified as containing biologically active secondary compounds. Most of the unique secondary metabolites that are present in lichens are derived from the polyketide pathway, with a few originating from the shikimic acid and mevalonic acid pathways (Table 1.1). Previous studies have suggested that the para-depsides are precursors to mefa-depsides, depsones, diphenyl ethers, depsidones and dibenzofurans.9,12... 

Roots benzoquinone atrovirinone and the depsidone atrovirisidone (Permana et al., 2001). 

Permana, D., Abas, F., Maulidiani, Shaari, K., Stanslas, J., Ali, A.M. and Lajis, N.H. (2005) Atrovirisidone B, a new prenylated depsidone with cytotoxic property from the roots of Carcinia atroviridis. Zeitschrift-fur-Naturforschung Section C, Biosciences 60(7/8), 523-526. 

In the third paper [53], a new structural class of noncatechol-containing integrase inhibitors, bisaroylhydrazines, was identified by modification of hits obtained in the previously presented studies. These compounds may provide valuable avenues for the development of HIV integrase inhibitors. Finally, also natural products, i.e., lichen acids containing depsides and depsidones, and their synthetic derivatives were identified from 3D database search as novel HIV-1 integrase inhibitors with IC50 values below 50 pM [54],... 

Neamati N, Hong H, Mazumder A, Wang S, Sunder S, Nicklaus MC, Milne GWA, Proksa B, Pommier Y. Depsides and depsidones as inhibitors of HIV-1 integrase discovery of novel inhibitors through 3D database searching. J Med Chem 1997 40 942-951. 

A new chlorinated depsidone (maldoxone 120) and a new spirocyclohexadienone (maldoxin 121) have been isolated from the culture medium of an as yet unidentified Xylaria species. Their role in the grisan-depsidone biosynthetic pathway was discussed [147]. 

Two new depsidones [aurantiacin A (36) (a white crystalline solid extraction yield 20 mg/1) and B (37) (an orange oil extraction yield 7.8 mg/1)] were isolated from the filtered culture medium of an Ascomycotina,... 

C18H14CI2O6, Mr 397.21, prisms, mp. 220-221 °C orange-red color on reaction with p-phenylenedia-mine. A depsidone from the lichen Argopsis frie-siana. 

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