Sesquiterpene lactones, chlorinated

Although the first survey listed 45 natural chlorinated sesquiterpene lactones, several such compounds were omitted in that coverage (1) and are described here. The novel sesquiterpene lactone chlorochrymorin (239) was isolated from Chrysanthemum morfolium (499), and the chlorohydrin graminichlorin (240) is found in Liatris graminifolia (500). The antibacterial AA-57 (241), which is related to pentalenolactone, is produced by a Streptomyces sp. (501). The plant Eupatorium chinense var. simplicifolium has yielded eupachifolin D (242) (502) (side-chain double bond stereochemistry revised (518)), and the new guaianolide andalucin (243) was characterized from Artemisia lanata (503). The previously known chlorohyssopifolins (1) have been studied for cytostatic activity, and the presence of one and even two chlorine atoms amplifies this activity (504). 

The Chinese Eupatorium chinense has afforded ten new sesquiterpenoids, three of which are chlorinated, eupachinilides C (263), E (264), and F (265) (518). The Chinese medicinal plant Eupatorium lindleyanum contains the chlorinated guaianes eupalinilides A (266), D (267), E (268), and H (269), amongst other non-chlori-nated eupalinilides and nine known sesquiterpenoids (579). The Oregon coastal perennial plant Artemisia suksdorfii contains four novel chlorinated sesquiterpene lactones 270-273 520). 

Examination of the Montenegro Achillea clavennae reveals the presence of three new chlorine-containing guaianolides 277-279 in addition to several known analogues (524). The first investigation of the Chinese medicinal plant Vernonia chinensis has uncovered the new chlorinated sesquiterpene lactones vemchinilides A (280), B (281), C (282) and E (283) (525). Vemchinilides B and E exhibit potent cytotoxic activity against the P-388 and A-549 cell lines. The structurally similar vemolide C (284) was found in the Cambodian traditional medicinal plant Vernonia cinera (fever, colic, malaria) (526). Indeed, vemolide C could be identical with vemchinilide A. 

Gonzalez AG, Darias V, Alonso G, Estevez E (1980) The Cytostatic Activity of the Chlorohyssopifolins, Chlorinated Sesquiterpene Lactones from Centaurea. Planta Med 40 179... 

Hamburger M, Wolfender J-L, Hostettmann K (1993) Search for Chlorinated Sesquiterpene Lactones in the Neurotoxic Thistle Centaurea solstitialis by Liquid Chromatographic-Mass Spectrometry, and Model Studies on Their Possible Artifactual Formation. Nat Tox 1 315... 

Zidom C, Ellmerer E-P, Konivalinka G, Schwaiger N, Stuppner H (2004) 13-Chloro-3-0-P-D-glucopyranosylsolstitialin from Leontodon palisae The First Genuine Chlorinated Sesquiterpene Lactone Glucoside. Tetrahedron Lett 45 3433... 

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