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Epipentenomycin

A facile synthesis of cyclopentadienone epoxides via thermal rDA cycloreversion of a tricyclodece-none epoxide and its acetal derivatives has been applied to the preparation of cyclopentanoid antibiotics. - This procedure has been used in an efficient synthesis of terrein, a mould metabolite from Aspergillus terreus, by rDA synthesis of cyclopentadiene epoxide intermediate (57). FVP conditions for these reactions typically involve temperatures of 420-600 C. Furan-derived DA adducts have also been used to generate cyclopentadienone epoxides. The thermal rDA reaction of the furan-derived DA adduct (58) proceeds at temperatures as low as 330 °C with complete cycloreversion and generation of epoxide (59) in nearly quantitative yield (equation 32). Subsequent elaboration led to epipentenomycin derivatives such as (60). [Pg.561]

For the more polar fungal metabolite epipentenomycin I (Scheme 4), an aqueous extract of the fungus was purified by two forms of ion-exchange chromatography. A final reverse phase HPLC step was employed, but the very polar mobile phase suggests that the compound was hardly retained by this stationary phase, and that this technique was only just within the limits of its usefulness for such a polar compound (6). [Pg.42]

Cispentacin, shown in Scheme 5, bears some structural similarity to epipentenomycin and was also isolated using two ion-exchange chromatography systems. The broth supernatant was loaded directly onto the ion-exchange column without any prior treatment, and unlike the epipentenomycin I isolation, the final step employed chromatography on a column of activated charcoal to afford a solid of 96% purity. The compound was then purified even further by recrystallization from acetone-ethanol-water (7). [Pg.42]

Bemillon, J., Favre-Bonvin, J., Pommier, M., and Arpin, N. (1989) First isolation of (-i-)-epipentenomycin I ffomPeziza sp. carpophores J. Antibiot. 42,1430-1432... [Pg.50]

The last example for an application of the classical Pummerer reaction corresponding to the 24 27 strategy of Scheme 20.7 is in the synthesis of pentenomycin analogues. Pohmakotr et used base-mediated elimination of trifluoroacetate to generate a cyclic vinyl sulfide 56, which was described as an epipentenomycin analogue fScheme 20.14T This transformation can be seen as a suitable methodology to reduce sulfoxides into sulfides by the Pummerer reaction with concomitant formation of a vinyl sulfide. [Pg.801]


See other pages where Epipentenomycin is mentioned: [Pg.46]    [Pg.46]   
See also in sourсe #XX -- [ Pg.42 , Pg.46 ]




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