2,4-Diene-1,6-diones

C2 HigFi81 202, DicarbonyKhexafluorobut-2-ene-2-yl)(hexafluoro-3,4-di(trifluoromethyl)hexa-2,4-diene-2,4-diyl)(pentamethylcyclopenta-dienyliridium)iridium (form I), 44B, 707 C24H1sFeOg, Tricarbonyl(5-acetyl-2,3-diphenyl-hepta-2,4-diene-1,6-dione-1,4-diyl)iron, 44B, 1131... [Pg.398]

Irradiation of the l,5-diene-3,7-dione (515) afforded the diketone (516), and later the isomer (517). The energetics of the excitation (triplet) of the diene-dione (515) have been investigated in detail, and compared with data for the corresponding l,5-dien-3-one and 4,4-dimethyl-5-ene-3,7-dione. [Pg.321]

In a synthetic study of the pinguisane compounds, Jommi et al. have converted the diene-dione (826) into 7-epipinguisone (827)382 and pinguisone (828)383 (Scheme 71). [Pg.184]

Further studies were reported241 242 on the degradation of deoxycholic acid with Pseudomonas species. Side chain-degraded products, for example the hydroxy-diene-dione (267), appeared to be important. Digoxin was reported as the main degradation product from Streptomyces mediated modification of digitoxin.243... [Pg.328]

Steroid l,4-dien-3-ones have been considered resistant to enol esterification, but powerful bases [PhsC , HC=C , or (Me3Si)2N ] convert the diene-dione (328) into its enolate anion, which affords the 3-benzoate (329) with benzoyl chloride. The 1,3,5-trienolate ion is, however, the product of kinetically... [Pg.329]

An interesting de-aromatization of phenols in superacidic medium has been reported. The reaction of oestrone (81) with a hydrogen fluoride-antimony pentafluoride mixture afforded the diene-dione (87) in high yield. Dienones such... [Pg.425]

Flash thermolysis of the diene dione (516) at 500°C gives cyclo-octa-2,5,7-triene-1,4-dione. At the same temperature the benzoannelated derivative (517) does not give the corresponding product but instead a more deep-seated rearrangement takes place to give (518). ... [Pg.176]

The source of 9 is not certain because the mono-cyclic diene-dione was prepared by thermolysis of the bicyclic precursor and traces of this precursor could be responsible for the observation of 9 The formation of 10 requires valence isomerization between the monocyclic and bicyclic structure since semidione is not formed from oxidation of 9 or its bicyclic precursor. Scheme 6 presents a possible rationalization for the formation of 10. [Pg.384]

However, when secondary propargyUc alcohols were used as substrates to perform reactions with 1,3-dicarbonyl compounds, tetrasubstituted furans 22 instead of diene-diones were obtained (Scheme 5.11) [17]. In this case, the process combines trifluoroacetic acid-promoted propargylation of 1,3-dicarbonyl compounds and a Ru-catalyzed cycloisomerization of the resulting y-keto alkynes 23. [Pg.184]

Jeger, O., und L. Ru iCka Zur Kenntnis der Triterpene. Uberfiihrung des 3-Amyrins in ein neues Dien-dion-Derivat. Helv. Chim. Acta 28, 209 (1945). [Pg.228]

Acetyloxy)-16,17a-[cyclopentylidene-bis(oxy)]-9-fluoro-llb-hydroxypregna-l,4-diene-3,20-dione. See Amcinomde. [Pg.8]

CONTROLLED RELEASE TECHNOLOGY - PHARMACEUTICAL] pol 7) Androsta-l,4-diene-3,17-dione [63-05-8]... [Pg.54]

Fluoro-llb,21-dihydroxy-16a-methyl-21-(phosphonooxy)-pregna-l,4-diene- 3,20-dione, disodium salt. See Dexamethasone sodium phospate. [Pg.413]

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