cis-Fused caryophyllenes from liquid cultures of Hebeloma longicaudum

A Caryophyllene-Related Sesquiterpene and Two 6,7-Seco-caryophyllenes from Liquid Cultures of Hebeloma longicaudum

“…A facile loss of this side chain under EIMS conditions accounts for the lack of a molecular ion in the EIMS spectrum of 2 . Several of the 1 H and 13 C signals of 2 bear striking resemblance to the signals of a four-membered ring of the previously described hebelophyllenes A−C isolated from the same fungus …”

“…Kummer (Cortinariaceae) is an ectomycorrhizal fungus producing abundant ectomycorrhizae with conifer species providing increased host plant growth and survival. , Its potential for nursery inoculation prompted us to study the metabolites produced when the fungus was grown in liquid culture. In the present study we report the isolation and structure elucidation of three new caryophyllene-related sesquiterpenes, hebelophyllenes D−F ( 1 − 3 ), which are co-metabolites of the recently described cis -caryophyllenes, hebelophyllenes A−C …”

“…Hebelophyllenes D−F ( 1 − 3 ) are related to the previously described hebelophyllenes A−C, which are representatives of the small group of cis -caryophyllenes. ,, …”

“…The fungus was grown as described previously . The ethyl acetate extract of the filtered broth was subjected to flash column chromatography on Si gel and the crude fractions were further purified to provide pure products ( 1 − 3 ).…”

“…The TROESY spectrum of 3 indicates cis -substitution of the four-membered ring (cross peak between H-1 and H-9) and also allows us to assign the olefinic protons at C-14. All of the above information leads to structure 3 for hebelophyllene F. Assuming a biosynthetic relationship among the lactone 2 , the ester 3 , and the hebelophyllenes A−C, one can expect the absolute configuration of 2 to be 1 S ,3 S ,8 R ,9 S and that of 3 to be 1 S ,3 S ,9 S . The absolute configuration of 2 at C(4) and of 3 at C(5), however, remains undetermined.…”