L- -1,3-propanedione

Chemical Name 1,3-Propanedione, l-(4-(l,l-dimethylethyl)phenyl)-3-(4-methoxyphenyl)-... 

Diaminomaleonitrile (178) and l-phenyl-6-(triisopropylsilyl)-hexa-l,5-diyne-3,4-dione (PhC CCOCOC=< SiPr j gave 5- phenylethynyl-6-(triisopropylsilyl)ethynyl-2,3-pyrazinedicarbonitrile (177) (AcOH, 20°C, 5 min 72%) ° the same diamine (178) and 3,3,3-trifluoro-l-p-tolyl-l,2-propanedione (l, CCOCOC6H4Me-p) gave 5-p-tolyl-6-trifluoromethyl-2,... 

Propanedione, l-(5-methyl-2-furanyl)-, l-(5-methyl-2-furyl)propane-l,2-dione,... 

Fig. 8. Molecular stmctures of selected sensitizers (18) thiapyryhum dye [25966-12-5] , (19) difluoroboron-l,3-diphenyi-l,3-propanedionate (DPBDK) (20)...

Dibenzoylmethane (l,3-diphenyl-l,3-propanedione) [120-46-7] M 224.3, m 80 . Crystd from pet ether or MeOH. 

Thus, the lithiated SAMP hydrazones of various methyl ketones on addition to 2-(aryl-methylene)- , 3-propanedionates and propanedinitriles provide, after the removal of the auxiliary, (R)-2-( l-aryl-3-oxobutyl)-1,3-propanedioates and -propanedinitriles with high enantiomeric excess (> 95%) in 50 82% yield (sec Table 6) 195,197. Using similar methods optically active (5-lactones (90% to > 96% ee) are obtained198. 

If the ligand X2 in a pentacoordinate triorganotin compound is potentially bidentate, such as the anion of l,3-diphenyl-l,3-propanedione or ofiV-benzoyl-N-phenylhydroxylamine, the tin atom is constrained to a cis-RsSnXj type of geometry, e.g., the triphenylstannyl derivatives of... 

CD] lxlO 3 M [substrate] 1 M room temperature, spectra measured after 30 min, d-doublet, s-singlet l-Phenyl-l,2-propanedione. 

The plasma half-life of cathinone is 1.5 hours. The primary metabolites are norpseudoephedrine, norephedrine, 3,6-dimethyl-2,5-diphenyl-pyrazine, and l-phenyl-l,2-propanedione (Szendrei 1980 Brenneisen etal. 1986 Guantai and Maitai 1983). However, norpseudoephedrine and norephedrine also originate directly from the leaves, as well as being metabolic products (Widler et al. 1994). Maximal plasma concentrations of norephedrine and norpseudoephedrine are reached at about 3.3 and 3.1 hours, respectively. These two drugs have a much longer duration of action than cathinone, where terminal half-lives could not be calculated after 10 hours. 

CioHi2N4UJ5 1-Phenyl-l, 2-propanedione-2-oxime thiosemicarbazone Spectrophotometric Ni 33... 

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