with 7 ml. of water and 3 ml. of pyruvic acid and allowed to stand a t room temperature overnight and a t 60" for 2 hr. After dilution with water, the product was extracted with chloroform and the chloroform sohtion was washed with water, 5% potassium bicarbonate, water, and dried over magnesium sulfate. The solvent was removed in vacuo and the residue was chromatographed on 50 g. of neutral alumina and eluted with benzene-chloroform mixtures. From the benzene eluates there was obtained 200 mg. of IV, m.p. 126-131 '. Recrystallization from acetone-petroleum ether gave material of m.p. 131-132", A: : : o H 237 mp, E = 9,900. Anal. Calcd. for C:sHnOa: C, 70.08; H, 7.53. Found: C, 69.75; H, 7.78. From the fractions corresponding to 1-20% chloroformbenzene there was recovered 400 mg. of I (R = 0), m.p.dl-Aeeto~y-A~~~~-pregnadieneJ,11,8O-trione (VI).g A solution of 5.0 g. of cortisone acetate-3,2O-bissemicarbazone* (V) in 100 ml. of acetic acid containing 5 ml. of acetic anhydride was refluxed in a nitrogen atmosphere for 1 hr. The pale yellow to red reaction mixture was concentrated in vacuo to a volume of 60 ml. and treated with 30 ml. of water and 15 ml. of pyruvic acid, and allowed to stand a t room temperature for 40 hr. and a t 60" for 2 hr. After dilution with water, the product was extracted with chloroform and the chloroform solution was washed with water, 5% potassium bicarbonate, water, and dried over magnesium sulfate. 226-229". The solvent was removed in vacuo and the residue waei chromatographed on 200 g. of neutral alumina and elution with benzene afforded after crystallization from acetoneether, 1.37 g. (38%) of VI (R = 0), m.p. 186-187", X: t : ' ' 237-238 mjt, E = 25,200, identical in the infrared spectrum with an authentic sample.I0 Anal. Calcd. for C Z S H~~O~: C, 71.85; H, 7.34. Found: C, 71.96; H, 7.26.Further elution of the chromatograph column with 50% benzene-ethyl acetate gave 2.47 g. (61%) cortisone acetate (V), thus affofdmg the Ala compound VI in co. 91% yield based on recovered cortisone. In several typical preparations a direct yield of 40 to 46% of VI has been attained. 1 lj3,11-Dihydroxy-A4* 16-pi egnadiene-3,WO-dione (VII). '1 21-Aceto~y-A~*~~-pregnadiene-3,11,2O-trione was converted to the corresponding 3,20-bissemicarbazone derivatives and reduced with lithium borohydride by the method of Wendler, Huang-Minlon, and Ti~hler.1~ The reversal of the semicarbazone w m carried out as described above with pyruvic acid to give VII, m.p. 153-156". A sample for analysis was chromatographed on neutral alumina and eluted with chloroform to afford VI1 crystallized from acetone-petroleum ether, m.p. 159-161", A~~~o A
The cyclization of ethyl a-keto-a'-(3'-tnethoxy-2-biphenylyl)-succmate (II) in 80% sulfuric acid yields both 3-methoxyand l-methoxyphenanthrene-9,10-dicarboxylic acid anhydrides (V and VII). The isomeric ethyl a-keto-a'-(4'-methoxy-2biphenylyl)-succinate (III) in a mixture of hydrobromic and acetic acids yields both 2-methoxyphenanthrene-9,10-dicarboxylic acid anhydride (VI) and 2-methoxy-10-phenanthroic acid (XIX). Cyclization of the acetylation product obtained from the anion of ethyl-«-(3-methoxy-2-biphenylyl)-propionate (XV) yielded what is believed to be 3-methoxy-9,10-dimethylphenanthrene.
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