Glutinopallanes

Drimane, farnesane, glutinopallane, protoilludane, isolactarane, and guaiane sesquiterpenes have been isolated so far in a few Lactarius species therefore, they may be considered chemotaxonomic markers. By contrast, large quantities of marasmane, lactarane and secolactarane metabolites occur in almost all Sections, as reported in Table 24. 

Rearranged marasmane skeletons glutinopallane and isolactarane sesquiterpenes... 

The only two known natural glutinopallane sesquiterpenes (8.2,8.3) have been isolated from Lactarius glutinopallens (42) (Table 8). Their structures are strictly related to velutinal esters (7.14, 7.15) for the presence of the cyclopropane ring and the 7a,8a-epoxyde, and to rubrocinctals 7.7 and 7.8 for the carbomethoxy group at C-3. 

Fatty acid esters of other marasmane sesquiterpenoids, as the two rubrocinctal derivatives 7.6 and 7.8, have been isolated so far only from L. rubrocinctus (23). Of limited distribution are also the farnesane fatty acid esters 1.3-1.9 (8), drimenol (3.2-3.6) and uvidin A (3.16-3.20) esters (11), violascensol lactarinate 5.2 (23), and the two glutinopallane esters 8.2 and 8.3 (42). Further unprecedented sesquiterpenoids are the guaiane esters 4.10-4.13 contained in intact specimens of Lactarius species of the Section Dapetes (14, 16, 21, 22). Various mixtures of yellow esters 4.12 and 4.13, red stearoylsangol (4.11), and blue stearoyldeterrol (4,10) are responsible for the beautiful colours of the latex of these species. 

The only two known natural glutinopallane sesquiterpenes 8.2 and 8.3 were isolated from frozen fruiting bodies of L. glutinopallens extracted with CH2CI2 (74). The two esters were separated by preparative HPLC on a RP-18 column with Me0H-H20, 95 5, the fatty acids being identified by GC after methanolysis, as palmitic and stearic acids. In the EIMS spectra of glutinopallal esters, the molecular ions at... 

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