Strychninonic acid

Strychninolic acid, C2iH220gN2, obtained by reduction of strychninonic acid with sodium amalgam, forms long prisms, m.p. 238°, and yields an acetyl derivative, needles, m.p. 281° eorr.). 

Stryctminic acids, 561 Strychninolic acid, 570 Strychninolone, 570 Strychninonic acid, 570 Strychnolethaline, 372 Strychnoline, 564... 

The Na lactam in strychninonic acid (XXXVIII) (50) and brucinonic acid (51) opens with boiling 5 N hydrochloric acid for 30 minutes or with 1 N NaOH at 0° for 48 hours. The alkaline hydrolysis was only reported for brucinonic acid it is interesting to note that, under these conditions, some elimination of glycolic acid also occurs (cf. Section II, B, 3). 

A stereoelectronic argument (62) would suggest quasi-axial addition leading to the right configuration (XLIV) for dihydrostrychninonic acid. The reduction of strychninonic acid to the epimeric strychninolic acid is governed simply by the more ready accessibility of the outer side of the ketone carbonyl group (62). 

This reagent has been used very frequently, either with barium hydroxide or with formic acid, to oxidize a-keto acids as either acids or lactams thus, strychninonic acid (XXXVIII) is converted by H2O2/ Ba(OH)2 into CLXX, in this case with concurrent base-catalyzed elimination of the glycolic acid residue (140). Very similar is the oxidation of dihydrostrychninone (CLXXI) in formic acid and hydrogen peroxide... 

Since strychninonic acid does not contain an ethylenic double bond and is non-basic, oxidative cleavage of the double bond must have resulted... 

Strychninonic acid must be an a-ketoamide, the diagnostic barium hydroxide-hydrogen peroxide oxidation (147) giving carbon dioxide, glycolic acid (strychninolone type of cleavage), and the amino acid Ba(OH)2 + H2O,... 

The amide of the newly generated a-ketoamide cannot be Na-CO since benzylstrychnine, under similar conditions, gives the benzyl analog of strychninonic acid (135). The oxidation of strychnine to strychninonic acid may be represented by the partial formulas ... 

Strychninonic acid, CgiHaoOgNg. 2HgO, obtained by Leuchs in 1908, crystallises from hot water in colourless prisms, m.p. 265-7° (corr., dry), [a] ° — yields a monoethyl ester, m.p. 209-210° (co7r.), and... 

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