Diterpene jatrophone

N.A. Jutrophine, emetic, purgative oil, diterpene jatrophone, isovitexin, resins, isophytosterol, tannin, cyanidin, apigenin, histamine.145-146 This herb is toxic. A folk remedy for cancer. Treat asthma, constipation, diabetes, diarrhea. It is a disinfectant, laxative. Externally applied to piles and bums. 

Carbonylative coupling of vinyl triflates with organotins (12, 470-471).3 The final step in a synthesis of the macrocyclic diterpene jatrophone (2) was effected by carbonylative coupling of a vinyl triflate with vinyltin catalyzed by bis(acetonitrile)-dichloropalladium. 

In a paper discussing strategies for the synthesis of the macrocyclic diterpene jatrophone, brief comment is made disclosing that chromous sulphate can cleanly effect the stereospecific reduction of a-oxoacetylenes to the corresponding E-enone, analogous to the reduction of acetylenic alcohols." ... 

The Stille-Hegedus synthesis of the diterpene jatrophone took advantage of an intramolecular carbonylative Stille coupling between a vinyl triflate and a vinylstannane motif to forge the macrocycle found in the natural product (see below). 

An example of the successful application of the Corey-Kim oxidation of a 3-hydroxyketone to yield a 1,3-diketone in natural product synthesis is illustrated by the total synthesis of ( )-jatrophone. 12 As shown below, the presence of the C-2 methyl group of 44 allowed for the clean conversion to desired diketone 45 in one step (i.e., no need for reductive desulferization). The Corey-Kim oxidation was then actually used a second time in the sequence to introduce another ketone and ultimately afforded the desired macrolide diterpene 46. 

Diterpenes from many species are well known for their biological activity and are amongst the most widely distributed terpenes in the plant kingdom. However, most of them combine both high antiparasitic activity as well as high cytotoxicity to mammalian cells. Both jatrogrossidione (50) and jatrophone, isolated from Jatropha... 

Similarly, the vinyUithiums 130 and 136, and the Hthiated cyclohexenic reagent 138 serve as useful building blocks for the synthesis of the macrocycHc diterpene antileukemic (it)-jatrophone (135) (1990JA8465), the sesquiterpenoid (+)-asteriscanolide (137) (2000JA2742), and the marine natural product nakienone B (139), respectively (Figure 5) (1996TL4679). 

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