Jatrophane diterpene

Leafy Spurge Root Extractives. Prior chemical examinations of leafy spurge have considered only aerial portions of the plant. Our recent chemical examination of root material relative to mammalian toxicity and/or allelopathy (29) resulted in the isolation and characterization of two new jatrophane diterpenes (esulone A (IX) and esulone B (X)) from the ether extract of the roots. Biological assay of esulone A showed it to be moderately phytotoxic (29% root length reduction (lettuce seeds) at 250 ppm), moderately toxic (LD50 78 23 mg/kg) and mildly Inflammatory (10 5 to 10 M, dermal) to mammals with no hyperplasia. 

Jatrophane diterpenes have not been previously described in E. esula, although twelve of the compounds have been described in other species of Euphorbia (31-37) and Jatropha gossypiifolla (38, 39). 

The unique structural character of these diterpenes and their exclusive distribution in the family Euphorblacae may allow their use as specific chemotaxonomlc markers within the family. Application of analytical HPLC methods developed in the Isolation of the jatrophane diterpenes to extracts of other E. esula accessions has revealed distinctively different unidentified jatrophane diterpenes (30) among the accessions. The rarity and exclusivity of these compounds within Euphorblacae warrants continued chemical examination and differentiation of E. esula accessions in relationship to successful Insect biological control. 

Scheme 102.7 The cyclization of GGPP affords the macrocyclic lathyrane and jatrophane diterpenes...

Corea G, Fattorusso E, Lanzotti V, Taglialatela-Scafati O, Appendino G, Ballero M, Simon PN, Dumontet C, Di Pietro A (2003) Jatrophane diterpenes as P-glycoprotein inhibitors. First insights of stmcture-activity relationship and discovery of a new powerful lead. J Med Chem 46 3395... 

Corea G, Di Pietro A, Dumontet C, Fatlorusso E, Lanzotti V (2009) Jatrophane diterpenes from Euphorbia spp. as modulators of multidrug resistance in cancer therapy. Phytochemistry Rev 8 431... 

Schnabel, C. Hiersemann, M. 2009. Total synthesis of jatrophane diterpenes from euphorbia characias. Org. Lett. 11 2555-2558. 

Thus, diterpenes have shown a physiological role in the organisms (gibberelUn, phytol, vitamin A, retinol), a specific taxonomic distribution (jatrophanes, lathyrane), a variety in their scaffold, inspiring chemists for the developing of parallel synthesis, and last but not least a huge array of therapeutic uses. 

Barile E, Borriello M, Di Pietro A, Doreau A, Fattorusso C, Fattorusso E, Lanzotti V (2008) Discovery of a new series of jatrophane and lathyrane diterpenes as potent and specific P-glycoprotein modulators. Org Biomol Chem 6 1756... 

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