Methyl anhydroberberilate

The same ester (135) was also obtained by photooxygenation of 131 in methanol in the presence of Rose Bengal in addition to the spirobenzyliso-quinoline 136 and methoxyberberal (137) in 57, 12, and 16% yields, respectively irradiation without Rose Bengal resulted in the same products but in 10, 40, and 1% respective yields (93). Hydrolysis of 13-acetoxyoxyberberine (116) gave methyl anhydroberberilate (138) (89,91,92). 

The methoxyberberine betaine (83) will undergo acyl migration in aqueous THF to give the imide methyl isoanhydroberberilate (94). That acyl migration had indeed occurred was shown by the conversion of the betaine (83) into the acetoxy-enamine (95) by acetic anhydride and pyridine, followed by hydrolysis of this by methanolic potassium hydroxide to the known methyl anhydroberberilate (97). The two isomeric compounds (94) and (97) react differently when treated with sodium borohydride in ethanol, the former suffering only solvolysis to noroxy-hydrastinine (98) and the diester (99) and the latter reduction to the ortho-ester (96). This ortho-ester, on A -methylation and further reduction with sodium borohydride, yields hydrohydrastinine and i -meconine. ... 

If, on the other hand, 8-methoxyberberinephenolbetaine is 0-acetylated, and then treated with methanol ic potassium hydroxide in the presence of air, no rearrangement occurs, and methyl anhydroberberilate is obtained. 

Berberilic acid, CgoHjgOgN, m.p. 177-82°, is dibasic, and furnishes a dimethyl ester, m.p. 173°. When heated to about 180°, the acid passes into ANHYDROBERBERiLic ACID, CjgHjjOgN, colourless needles, m.p. 236°, soluble in alkali carbonate solutions with the formation of berberilates. When ammonium berberilate is dried under reduced pressure, a molecular proportion of ammonia is lost with the formation of the ammonium salt of the anhydro-acid, from which other salts, and the methyl ester, m.p. 178°, have been obtained. Berberilic acid is hydrolysed by hot dilute sulphuric acid to hemipinic acid (I) and oi-aminoethylpiperonylic acid (II), large tabular crystals, m.p. 180-2°. Berberilic acid is therefore represented by (III). 

Anhalonium alkaloids, pharmacology, 160 Anhalonium spp., 154 Anhydroberberilic acid, 332 Anhydroecgonine, 97 Anhydrolupinine, 120 Anhydroxatine, 770 Anisomeles malabaTica, 779 Af-(2-p-Anisylethyl)-AT-methyl-cinnamide, 330, 631 Annona anibotay, 371 Annotinine, 752, 753, 755 Anodmine, 47 Anolobine, 317... 

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