(-)-Versicolamide B and (+)-Versicolamide B are spiroindole alkaloids isolated from the fungus Aspergillus that belong to a class of naturally occurring 2,5-diketopiperazines.[1] The versicolamides are structurally complex spiro-cyclized versions of prenylated cyclo(L-Trp-L-Pro) derivatives which possess a unique spiro-fusion to a pyrrolidine at the 3-position of the oxindole core together with the bicyclo[2.2.2]diazaoctane ring system. While (-)-versicolamide B was isolated from the marine fungus Aspergillus sp. [2] the enantiomer (+)-versicolamide B was isolated from the terrestrial fungi Aspergillus versicolor NRRL.[3] The total asymmetric syntheses of both enantiomers have been achieved and the implications of their biosynthesis have been investigated.[4]

Structures of (-) and (+) Versicolamide B

References

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  1. ^ Borthwick AD (May 2012). "2,5-Diketopiperazines: Synthesis, Reactions, Medicinal Chemistry, and Bioactive Natural Products". Chemical Reviews. 112 (7): 3641–3716. doi:10.1021/cr200398y. PMID 22575049.
  2. ^ Tsukamoto S, Kawabata T, Kato H, Greshock TJ, Hirota H, Ohta T, Williams RM (February 2009). "Isolation of Antipodal (−)-Versicolamide B and Notoamides L− N from a Marine-Derived Aspergillus sp". Organic Letters. 11 (6): 1297–1300. doi:10.1021/ol900071c. PMC 2829632. PMID 19281134.
  3. ^ Greshock TJ, Grubbs AW, Jiao P, Wicklow DT, Gloer JB, Williams RM (April 2008). "Isolation, Structure Elucidation, and Biomimetic Total Synthesis of Versicolamide B, and the Isolation of Antipodal (−)-Stephacidin A and (+)-Notoamide B from Aspergillus versicolor NRRL 35600". Angewandte Chemie International Edition. 47 (19): 3573–3577. doi:10.1002/anie.200800106. PMC 2829633. PMID 18389509.
  4. ^ Miller KA, Tsukamoto S, Williams RM (April 2009). "Asymmetric total syntheses of (+)-and (−)-versicolamide B and biosynthetic implications". Nature Chemistry. 1 (1): 63–68. Bibcode:2009NatCh...1...63M. doi:10.1038/nchem.110. PMC 2840645. PMID 20300443.