Isomarasmane, and Normarasmane Sesquiterpenes

Of the other naturally occurring marasmanes included in Part 6, the very stable 5,10a,13-trihydroxymarasm-7(8)-ene (6.6) and lactaropalli-dine (6.5) 56) are of special interest. Triol 6.6 is one of the few 

Part 6 also includes a few isomarasmanes (6.9-6.11) and nor-marasmanes (6.12-6.22). The former are synthetic compounds and were obtained by thermal isomerization of the corresponding marasmanes (see chemical part). The 13-normarasmane isomers 6.12 and 6.13 are among the few known norsesquiterpenes of Lactarius, The two compounds were isolated (58) together with compound 6.6 from an ethanol extract of Lactarius vellereus. The normarasmane ketones may derive in mushrooms from lactaropallidine (6.5) by 3-deformylation and oxidation at C-7. 

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