Methyl glycyrrhetate

Methyl desoxyglycyrrhetate 61 Methyidigoxin 104 Methyl glycyrrhetate 61 Methyl iodide reagent 70 N-Methylphenylalanine 89 Methylsuccinic acid 249 Methyl sugars 188... 

Dean studied the hydrolysis (halogenolysis) of methyl glycyrrhetate, a hindered triterpenoid ester, in a number of solvents and found dimethylformamide superior to pyridine, lutidine, collidine, or N-methyl-2-pyrrolidone in both speed and extent of reaction. In addition, use of DMF facilitated workup the reaction mixture can be poured onto water and the mixture is acidified and extracted with ether. 

Methyl glycyrrhetate,--------Apply 5% palladium or platinum chlonde in 50%-----------[1 -... 

A soln. of methyl glycyrrhetate in glacial acetic acid hydrogenated 7 hrs. with PtOa at room temp, and atmospheric pressure methyl desoxoglycyrrhetate (startg. m. f. 5). Y 93.7%. E. J. Gorey and E. W. Gantrall, Am. Soc. 81, 1745 (1959). 

Hydrolysis of hindered esters. Aranda and Fetizon observed hydrolysis of a hindered ester group accompanying deacetylation with boiling quinoline. They then found that some hindered esters are hydrolyzed when refluxed in quinoline and acetic acid. This reaction can be accompanied by acetylation of hydroxyl groups, if present. Thus methyl 18a-glycyrrhetate is converted by this procedure into the acid (43% yield), the 3 3-acetate (26% yield), and the 3a-acetate (29% yield). 

Methyl-a,d-cthylenic sulfoxides, 377 Methyl farncsoate, 448 Methyl fluoride-Antimony penta-fluoride-Sulfur dioxide, 381 Methyl tluorosulfonate, 26, 48, 381-382 Methyl geraniate, 447 Methyl gibberellate, 186 Methyl a-D-glucopyranoside, 26 (3-Methyl glycopyranosides, 437, 438 Methyl 18a-glycyrrhetate, 501... 

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