Naphthoquinones occurrence

Table 1 gives an up-to-date compilation of selected natural products in the lapachol, furan and pyran-naphthoquinones classes, together with their occurrence and the biological activities investigated for each. 

The close relationship of Bulgaria and Daldinia with Hypoxylon in the Xylariaceae is illustrated by the occurrence in some Hypoxylon species of perylenequinones and their relatives (Table 22). The structure of hypoxylone (269), the main pigment of the dark purple carpophores of Hypoxylon sclerophaeum collected in French Guyana, followed from analysis of the and C-n.m.r. spectra and comparison with model systems 107). The naphthyl-naphthoquinone structure of hypoxylone suggests oxidative coupling between naphthalene-1,8-diol (258) and naphthalene-1,4,5-triol. 

Babula P, Adam V, Havel L, Kizek R (2009) Noteworthy secondary metabolites naphthoquinones - their occurrence, pharmacological properties and analysis. Curr Pharm Anal 5 47-68... 

Babula P, Adam V, Havel L et al (2009) Noteworthy secondary metabolites naphthoquinones— their occurrence, pharmacological properties and analysis. Curr Pharm Anal 5 47-68 Backorova M, Backor M, Mikes J et al (2011) Variable responses of different human cancer cells to the lichen compounds parietin, atranorin, usnic acid and gyrophoric acid. Toxicol In Vitro 25 37 ... 

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