Ethyl «-acetyl-0- propionate

Various 4-, 5-, or 4,5-disubstituted 2-aryIamino thiazoles (124), R, = QH4R with R = 0-, m-, or p-Me, HO C, Cl, Br, H N, NHAc, NR2, OH, OR, or OjN, were obtained by condensing the corresponding N-arylthiourea with chloroacetone (81, 86, 423), dichloroacetone (510, 618), phenacyichloride or its p-substituted methyl, f-butyl, n-dodecyl or undecyl (653), or 2-chlorocyclohexanone (653) (Method A) or with 2-butanone (423), acetophenone or its p-substituted derivatives (399, 439), ethyl acetate (400), ethyl acetyl propionate (621), a- or 3-unsaturated ketones (691), benzylidene acetone, furfurylidene acetone, and mesityl oxide in the presence of Btj or Ij as condensing agent (Method B) (Table 11-17). 

Using a 6-in. Vigreux column with a wide side arm, the checkers observed a boiling point of 166-168°/3 mm. for ethyl < -acetyl-/3-(2,3-dimethoxyphenyl)propionate and 176-179°/ 2 mm. for the acrylate. 

Ethyl acetoacetate, 29, 214, 399, 540, 629, 794, 887,1075,1128, 1268-1269,1272 p-Ethylacetophenone, 946,1084-1085 Ethyl acetopynivate, 251 Ethyl o-acetoxyacetoacetate, 540 Ethyl o-acetO Qrhexanoic acid, 541 Ethyl acetylacetoacetate, 1097 Ethyl a-acetyl-f3-(2,3-dimethoxyphenyl> propionate, 896 Ethyl acetyl eburicoate, 615 Ethyl acrylate, 928 N-Ethylallenimine, 1637 Ethylamine, 103,372,574,575,578,579,770 Ethyl p-aminobenzoate, 890 Ethyl 3-aminocitrazinate, 520 Ethyl azidoformate, 363-364 Ethyl benzalmalonate, 888 Ethylbenzene, 226,567,576, 719, 779,1061, 1287... 

Acetyltyrosine Ethyl Ester [C13H17NO4H2O (Mr 269.3) ethyl / /-acetyl-L-tyroslnate monohydrate ethyl (S)-2-acetamido-3-(-4-hydroxyphenyl)-propionate monohydrate]... 

The ketones are readily prepared, for example, acetophenone from benzene, acetyl chloride (or acetic anhydride) and aluminium chloride by the Friedel and Crafts reaction ethyl benzyl ketones by passing a mixture of phenylacetic acid and propionic acid over thoria at 450° and n-propyl- p-phenylethylketone by circulating a mixture of hydrocinnamic acid and n-butyric acid over thoria (for further details, see under Aromatic Ketones, Sections IV,136, IV,137 and IV,141). 

Preparation of a-Acety/amino-0-(5-Benzy/oxy-/ndo/yl-3)-Propionic Acid 15 grams a-acetyl-amino-0 -carboxy-/3-(5-benzyloxy-indolyl-3)-propionic acid was suspended in 225 ml water and the suspension refluxed and stirred in a stream of nitrogen until evolution of carbon dioxide ceased (about 2 hours). After cooling somewhat, 120 ml ethyl alcohol was added and the suspension refluxed until the product dissolved. Charcoal was added to the solution the mixture filtered hot, and the filter-cake washed with 50 ml hot 50% aqueous ethanol. 0 -Acetylamlno-/3-(5-benzyloxy-indolyl-3)-propionic acid, MP 164° to 166°C, which crystallized from the filtrate on cooling, was collected, washed with an ice-cold mixture of 15 ml ethanol and 45 ml water, and dried in vacuo over silica gel (yield 11.1 grams, 83%). 

Polyphosphoric acid in cyclization of ethyl a-acetyl-/3-(2,3-dimethoxy-phenyl)propionate to 6,7-dimeth-oxy-3-methylindene-2-carboxyl-ate, 40, 43... 

Ethyl a-ACETYL-/3-(2,3-DiMETHOXY-phenyl)propionate, 31, 56 Ethyl a-acetyl-/3-(3,4-dimethoxyphenyl)-propionate, 31, 58... 

Because of the difficulty encountered in acetylation of the complexed alcohol, it was of interest to see if the ester complex behaves in a normal fashion. Refluxing (HaO) [Cr(AcO-A)2] in methanol or ethanol caused methyl or ethyl acetate to be formed, while refluxing in ethyl propionate formed ethyl acetate. When the potassium salt was used in place of the oxonium salt no transesterification was observed this could be due to the necessity of acid catalysis or a difference in solubility in these essentially heterogeneous systems. The oxonium salt, (H30) [Cr(AcO-A)2], appears to have typical ester reactivity. 

Ethyl a-acetyl-8-(3,4-dimethoxy-phenyl)propionate, 31, 58 Ethylamine, 2-chloro-N,N-di-... 

Omeprazole is obtained [15] by the reaction of acetyl ethyl propionate 1 with ammonia to give ethyl -3-amino-2,3-dimethyl acrylate 2. Compound 2 was converted to to 2,4-dihydroxy-3,5,6-trimethyl pyridine 3 by treatment with methyl diethylmalonate. Treatment of compound 3 with phosphorous oxychloride produced 2,4-dichloro-3,5/6-trimethyl pyridine 4. 4-Chloro-3/5,6-trimethyl pyridine 5 was obtained by treatment of compound 4 with hydrogen. On treatment of compound 5 with hydrogen peroxide and acetic acid, 4-chloro-3,5,6-trimethyl-pyridine-N-oxide 6 was produced. Treatment of compound 6 with acetic anhydride gave 4-chloro-2-hydroxymethyl-3,5-dimethyl pyridine 7 which was converted to 2-hydroxymethyl-3,5-dimethyl-4-methoxypyridine 8 by treatment with sodium methoxide. Compound 8 was treated with thionyl chloride to produce 2-chloromethyl-3,5-dimethyl-4-methoxypyridinc 9. Compound 9 interacts with 5-methoxy-2-mercaptobenzimidazole to give 5-methoxy 2-[((4-methoxy-3,5-dimethyl-2-pyridinyl)methyl)thio]-lH-bcnzimidazole 10 which is oxidized to omeprazole 11. 

Ethyl acetoacetate, 31, 1, 57 32, 76, 84 Ethyl a-acetyl-/3-(2,3-dimethoxy-phenyl)acrylate, 31, 5(5, 58 Ethyl a-acetyl-/S-(3,4-dimethoxy-phenyl)acrylate, 31, 58 Ethyl q -acetyl-/3-(2,3-dimethoxy-phenyl)propionate, 31, 56 Ethyl a-acetyl-/3-(3,4-dimethoxy-phenyl)propionate, 31, 58 Ethylamine, 2-chloro-N,N-di-... 

RX. n-butyl bromide n-dodecanyl iodide cyclohexyl iodide ethyl bromo acetate methyl 2,3-di-O-acetyl-4-O-benzoyl-6-bromo-6-deoxy-ot-D-glucopyranoside methyl 2,3,4-tri-0-acetyl-6-deoxy-6-iodo-0 -D glucopyranoside l,2 3,4-di-0-isopropylidene-6-deoxy-6-iodo-a-D-galactopyranose methyl 2(R)-[(tert-butoxycarbonyl)amino]-3-iodo-propionate cyclic bis(trifluoromethyl)oxazolidinone bromide. 

B. Ethyl a-acetyl- - 2,3-dimethoxy phenyl) propionate. The product obtained in Part A is divided into two approximately equal portions, and to each are added 125 ml. of ethyl acetate and 5 g. of 5% palladium-on-carbon catalyst (Note 4). Each solution is shaken with hydrogen at pressures between 20 and 40 lb. in a low-pressure apparatus. About 45 minutes is usually needed for complete reduction. The two solutions are then combined, and the catalyst is removed by filtration and washed with 20 ml. of ethyl acetate. The ethyl acetate is distilled at atmospheric pressure, and distillation of the residue under reduced pressure yields 158-176 g. (56-63% over-all) of a colorless product collected at 175-177°/3 mm., 1.5042-1.5044 (Notes 3 and 5). 

By bacterial fermentation the calcium salt of lactic acid is decomposed into salts of simpler acids, e.g,y propionic, bulyric and valeric. As an acid lactic acid yields an ethyl ester with ethyl alcohol and as an alcohol it yields, with acetic anhydride, an acetyl derivative. The latter compound results from the putrefaction of muscular tissue, as this contains both lactic and acetic acid. 

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