Tiglianes

The Williams approach to bicyclo[5.4.0]undecane containing molecules such as the cyathins, striatins, dolastanes, clavularanes, grayanotoxins, tiglianes, and daphnanes also utilizes an oxidopyrylium cycloaddition to generate the ether constrained bicyclic (Scheme 4.81) (164). The object of the Williams study was to prepare the bicyclo[5.4.0]undecanes and investigate the regio- and stereocon-trolled oxidation of the substrate. 

The zirconacycle 259 is prepared by the reaction of Cp2Zr with the 1,6-enyne 258, and converted to the cyclopentenone 260 by the reaction of CO. The silylalkyne 258 is the appropriate substrate, because the terminal alkyne can not be used in this reaction [111]. The tricyclic skeleton of tigliane 263 has been prepared by the carbonylative... 

The phorbol 33 is a tigliane diterpene whose 12, 13-diesters play a principal role in efforts to understand biological activities such as carcinogenesis and... 

The transient intervention of a carbonyl ylids has culminated in numerous elegant approaches to total syntheses of natural products, such as the synthesis of the tigliane ring system (61-63) by Dauben [53] (Scheme 28). 

Tigliane (G5 C7 C61 C3) diterpenes include the highly irritant, toxic, co-carcinogenic, PKC activating phorbol esters from Euphorbiaceae plants. While not being activated by the parent compound phorbol, PKC is activated by plant-derived esters of phorbol, 4-deoxyphor-bol and 12-deoxyphorbol (e.g. 12-0-palmitoyl-16-hydroxy-phorbol 13-acetate, 12-deoxyphorbol 13-benzoate, 12-deoxyphorbol 13-phenylacetate, 12-deoxyphorbol 13-phenylacetate-20-acetate, sapintoxin A (4-deoxyphorbol 12-(2-methylamino)benzoate-l3-acetate) and 12-tetradecanoylphorbol 13-acetate (TPA)), as well as by synthetic phorbol esters. 

M3) (tigliane diterpene PE) sailors of Christopher leaf-poisoned water... 

Deoxyphorbol 13-phenylacetate (phorbol ester tigliane diterpene)... 

A liquid chromatography-tandem mass spectrometry (LC-MS-MS) method was developed to detect tumor-promoting diterpene esters of the tigliane and ingenane types within plant extracts. Fractionation on a Cig HPLC column was followed by MS-MS-multiple reaction monitoring (MRM). 

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