Pyrrole 4 - acetyl - 1 - ethyl - 5 - methyl

Pyrrole, 2-acetyl-1-ethyl Sd (roasted) Pyrrole, 2-acetyl-N-methyl Sd (roasted) Pyrrole, 2-carboxaldehyde Sd Hu ... 

The synthesis of pyrrolo[2,3- 7 pyridazines can be achieved by starting either with pyridazine, a tetrazine, or a pyrrole. Pyridazinone 80 reacts with bromomethyl derivatives to give poor yields of 81 <1996H(43)1863> (Equation 34), while 5-acetyl-2-methyl-4-nitro-6-phenyl-3(2//)-pyridazinone, after treatment with sarcosine ethyl ester for a brief time at room temperature, followed by acid hydrolysis afforded a good yield of 82 (70%) <1994S669>. 

Much more studied is the reaction of /8-dicarbonyl compounds with 2-amino-2-deoxyaldoses in particular, with 2-amino-2-deoxy-D-glu-cose (55), both in neutral and alkaline medium. In neutral methanol or aqueous acetone, 2-amino-2-deoxy-D-glucose reacts with 2,4-pen-tanedione to give52 54 3-acetyl-2-methyl-5-(D-arabino-tetrahydroxy-butyl)pyrrole (56a), and, with ethyl acetoacetate,55 the pyrrole 56b. Similar (tetrahydroxybutyl)pyrroles have been prepared from other /3-keto esters, such as ethyl 3-oxohexanoate, ethyl thiolacetoacetate, and diethyl 3-oxopentanedioate.53,56,56a... 

N-Heterocycles Pyridine Pyrazines Unsubstituted, 2,3-Dimethyl, MARM ++ 2,5-Dimethyl-3-ethyl, Methyl, 2-Ethyl-6-methyl, 2,5-Dimethyl, 2-Ethyl-5-methyl, 2,6-Dimethyl, Acetylmethyl, 2-(2-Furyl), Ethyl, 2-Methyl-5-(methylethyl), Trimethyl Pyrroles 2-Acetyl, N-Methyl-2-furyl, 1-Formyl, 1-Furfury 1-2-formyl, 5-Methvl-2-formvl Trimethylpyrazine (TMPy) (RV = 0.989)... 

In the experiments first described, 2-amino-2-deoxy-D-glucose was heated with an excess of the /3-dicarbonyl compound in the absence of solvent. The product so obtained from ethyl acetoacetate, m.p. 142°, [a]n 49.7°, had an analysis corresponding to that for ethyl 2-methyl-5-(D-ara6mo-tetrahydroxybutyl)pyrrole-3-carboxylate and was considered to have this structure (1). In the reaction with 2,4-pentanedione, a material (m.p. 98°, Md — 25.1°) was obtained which was described as 3-acetyl-2-methyl-5-(D-ara5fno-tetrahydroxybutyl)pyrrole (2). Boyer and Furth" repeated the latter reaction, but in methanol solution, and obtained a product, m.p. 133°, whose analytical data were in agreement with those for structure (2). 

In the reactions of 2-amino-2-deoxy-D-glucose with some /3-dicarbonyl compounds (such as ethyl acetoacetate, 2,4-pentanedione, or pyruvic acid) in alkaline solution, pyrroles lacking the tetrahydroxybutyl chain are obtained. The loss of this group cannot occur with the already formed (tetrahydroxybutyl)pyrroles, because these compounds, as exemplified by 3-acetyl-2-methyl-5-(D-ora wo-tetrahydroxybutyl)pyrrole (2), remain unchanged at the pH (9-10) of the reaction. The fission of the sugar chain most probably occurs for one of the intermediates of the reaction, for instance (79), and it may be formulated as a concerted-elimination reaction catalyzed by the hydroxyl ion, as indicated in Scheme C. The... 

Following formation of the S-Me derivative of ethyl 4-(1-benzyl-2-thia-oxopyrrolidin-3-yl)-5-(1,3-dioxobutyl)pyrrole-2-carboxylatewith methyl ir ide,the mixture was heated in a sealed Pyrex tube under nitrogen at SOX for 15 hours to produce ethyl 5-acetyl-6-benzyl-4-hydroxy-3,6,7,8-tetra-hydrobenzo-[1,2-b 4,3-b ]dipyrrole-2-carboxylate in 97% yield (ref.27)... 

Chapter V. Quinaldine (V,2) 2-methyl-, 2 5-dimethyl- and 2-acetyl-thiophene (V,8-V,10) 2 5-dimethyl- and 2 4-dimethyl-dicarbethoxy-pyrrole (V,12-V,13) 2-amino- and 2 4-dimethyl-thiazole (V,1 V,16) 3 5-dimethyl-pyrazole (V,17) 4-ethylpyridine (from pyridine) (V,19) n-amyl-pyridines from picolines) (V,28) picolinic, nicotinic and isonicotinic acid (V,21-V,22) (ethyl nicotinate and p-cyanopyridine (V,23-V,24) uramil (V,25) 4-methyl-(coumarin (V,28) 2-hyi ox3depidine (V,29). 

H-Pyrrole-2-carboxylic acid, 4-acetyl-3-ethyl-5-methyl-, ethyl ester X-ray, 4, 6, 160 <72JCS(P2)902>... 

Carbamidsanre N-(l-Hydroxy-2,2,2-trifluor-ethyl)- -(4-methoxy-benzylester) E14a/2, 60 (R-CHO/RO-CO-NH2) Pyrrol 4-Acetyl-2-ethoxycarbonyl-5-methyl-3-trifluormethyl-E6a, 625 (F3C-CO-CH2-COOR + HN02 2,4-Pentandion/Zn)... 

K.55) Ethanone, l-( 1-ethyl-1 //-pyrrol-2-yl)-, l-(l-ethylpyrrol-2-yl)ethanone, l-ethylpyrrol-2-yI methyl ketone, 2-acetyl- 1-ethylpyrrole 139741-41-8] FEMA 3147... 

Ludwig. This compound has an empirical formula corresponding to structure (1) and shows the ultraviolet and infrared" absorptions of a pyrrole-3-carboxylic ester. Its acetylation gives a tetra-O-acetyl derivative." Oxidation with lead tetraacetate yields ethyl 5-formyl-2-methyl-pyrrole-3-carboxylate (4), identical with the compound prepared in a different way. Oxidation with potassium permanganate in alkaline solution at low temperature yields 3-(ethoxycarbonyl)-2-methylpyrrole-5-carboxylic acid (7) which can be transformed " into the diethyl ester (8), identical... 

Ethyl 2-methyl-4-(D-ara6mo-tetrahydroxybutyl)pyrrole-3-carbothiolate (18) yields a tetra-O-acetyl derivative, and, on oxidation with periodic acid, affords ethyl 4-formyl-2-methylpyrrole-3-carbothiolate (22). Lactone (27) gives a tri-O-acetyl derivative and, on alkaline hydrolysis, consumes one equivalent of base and furnishes 2-methyl-4-(D-arofemo-tetrahydroxy-butyl)pyrrole-3-carboxylic acid (19) in almost quantitative yield. This acid can, in turn, be transformed into a tetra-O-acetyl derivative, and, when oxidized with sodium metaperiodate, it gives 4-formyl-2-methyl-pyrrole-3-carboxylic acid (23). Attempts to determine the size of the lactone ring in compound (27) by oxidation with sodium metaperiodate were unsuccessful three moles of metaperiodate were consumed per mole, as if, during the oxidation, hydrolysis of the lactone had occurred. 

FIGURE XIV-1 B The amide II, imide III, and lactam IV configurations in l-acetyl-3-ethyl-l,5-dihydro-4-methyl-2/f-pyrrol-2-one I. ... 

Observations of the reactions of the few known 2-aminopyrroles are sparse. 2-Amino-4-ethyl-3,5-dimethyl- and 2-amino-3,4-diethyl-5-methyl-pyrrole could not be acetylated, benzoylated or diazotized. It is not clear whether these failures were due to inability to react or to instability . Acetyl and benzoyl derivatives were prepared from 2-amino-1-ethyl- and... 

Pyrrole- and Furan-fused Thio diens and Related Compounds.— The interest in the chemistry of thienopyrroles is still increasing. Starting from 2-amino-3-carbonyl-substituted thiophens obtained by the Gewald reaction, the A -ethoxy-carbonylmethyl derivative (245) was prepared either by direct alkylation with ethyl bromoacetate, or by reductive alkylation with methyl glyoxalate. The compounds (245) were then ring-closed directly, or after acetylation, to the... 

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