The synthesis of 1,4-diketones

1976 ◽  
Vol 29 (2) ◽  
pp. 339 ◽  
Author(s):  
S Nimgirawath ◽  
E Ritchie ◽  
WC Taylor
Keyword(s):  
Michael Addition ◽  
Addition Product ◽  
Phenacyl Bromide ◽  
Unsaturated Ketone ◽  
Lower Yield ◽  
Derivatives Of ◽  
Acyl Derivatives ◽  
Moderate Yield

Recent methods for the synthesis of 1,4-diketones are briefly reviewed.Zinc and phenacyl bromide in dimethoxyethane afforded 1,4-diphenylbutane-l,4-dione in moderate yield, but other solvents or metals examined gave no or a lower yield. The route is unsatisfactoryfor aliphatic 1,4-diketones. Attempts to use 'levulinyl chloride' to acylate olefins or acetylenes were fruitless. Routes involving aldol condensations of hexane-2,5-dione or its monoacetal had very restricted success, as did those depending on the halogenolysis of acyl derivatives of phenacylmalonic ester. A fairly general route to 1,4-diketones was found in the sequence: valine to N-acylvaline to oxazol-5-one to Michael addition product with an α, β-unsaturated ketone followed by alkaline hydrolysis.The Michael addition is not regiospecific and valine derivatives may also be isolated. Yields of 1,4-diketones are only moderate but the synthesis is quick and convenient.

The chromous chloride promoted addition of N-haloamides to olefins. V. The addition of N-chloroamides to enol ethers: synthesis of acyloxy and acyl derivatives of α-amino acetals and ketals (aldehydes and ketones) and of 2-amino sugars

1978 ◽  
Vol 56 (1) ◽  
pp. 119-130 ◽  
Author(s):  
Hugues Driguez ◽  
Jean-Paul Vermes ◽  
Jean Lessard
Keyword(s):  
Addition Product ◽  
Amino Sugars ◽  
Enol Ethers ◽  
Aldehydes And Ketones ◽  
Work Up ◽  
Derivatives Of ◽  
Chromous Chloride ◽  
Acyl Derivatives

The chromous chloride promoted addition of N-chlorocarbamates and N-chlorocarboxamides to 1-methoxycyclohexene, ethoxyethylene, dihydropyran, and (1-methoxyethylidene)-cyclohexane gave, in 60 to 85% yields, either α-acyloxy- or α-acylamino ketals and acetals, or the corresponding ketones and aldehydes depending on the work-up conditions. The regio-specificity of the addition was higher with the first two enol ethers (≥97%) than with the latter two (≥85%). N-Chlorourethane was added to 17-methoxymethylenandrost-4-en-3-one (19) and the sole addition product isolated was the 17α-chloro-20-ethoxycarbonylamino derivative 20 in 75% yield. Additions to triacetyl-D-glucal and 3-O-acetyl-4,6-O-benzylidene-D-glucal followed by solvolysis under Koenigs–Knorr conditions led predominantly to 2-amino-gluco-pyranosides in 30 to 65% yields, whereas additions to 3-O-acetyl-4,6-O-benzylidene-D-allal gave 2-amino altropyranosides in 40 to 56% yields.

scholarly journals Synthesis of substituted pyrrolo[2,3-d]pyrimidines and pyrido[2,3-d]pyrimidines in the one-pot condensation of 2-thio-6-aminouracil, arylglyoxals and CH-acids

2019 ◽  
Keyword(s):  
Acetoacetic Ester ◽  
Phenacyl Bromide ◽  
Unsaturated Ketone ◽  
Activity Profile ◽  
One Pot ◽  
Ch Acids ◽  
One Pot Condensation ◽  
The One ◽  
Phenacyl Derivatives ◽  
Derivatives Of

We have developed some available and effective methods for the synthesis of substituted pyrrolo[2,3-d]pyrimidines and 5,8-dihydropyrido[2,3-d]pyrimidines based on the three-component condensation of 6-amino-2-thiouracil with arylglyoxal hydrates and N,N-dimethylbarbituric acid or acyclic β-dicarbonyl compounds: acetylacetone (acetoacetic ester). It was shown that the optimal product yields were obtained by boiling the reagents in acetic acid. Thus, the synthesis of pyrrolo[2,3-d]pyrimidines took 15-20 minutes, while the precipitation of 5,8‑dihydropyrido[2,3-d]pyrimidines formed only after 2 hours. We proposed possible mechanisms for the formation of anelated pyrrole and pyridine rings. In both cases, the reaction includes the formation of an intermediate of α,β-unsaturated ketone with the participation of arylglyoxal and CH-acid (N,N-dimethylbarbituric or acetylacetone (acetoacetic ester)), nucleophilic addition of 6-aminothiouracil via an activated double bond, condensation of carbonyl and amino groups. The formation of the cycle takes place exclusively with the participation of the acetyl moiety, while the pyrrol one forms during the condensation of the aroyl moiety and the 6-amino group of thiouracil. A series of synthesized pyrrolo[2,3-d]pyrimidines was modified by alkylation. As it was expected, alkylation proceeds at the sulfur atom, that allowed a significant increase in the solubility of the obtained products. The reaction was carried out in DMF by stirring the initial reagents at 60ºC (reaction with methyl iodide) or boiling them (alkylation with phenacyl bromide), whereby S-methyl and S-phenacyl derivatives of pyrrolo[2,3-d]pyrimidines were obtained. The spectral data of 1H NMR showed that S-methylation products form solvates with DMF as 1:1. The synthesized compounds can become the basis to create small libraries of anelated pyrimidines with improved antiviral activity profile.

Cupin Variants as Macromolecular Ligand Library for Stereoselective Michael Addition of Nitroalkanes

2019 ◽  
Author(s):  
Nobutaka Fujieda ◽  
Miho Yuasa ◽  
Yosuke Nishikawa ◽  
Genji Kurisu ◽  
Shinobu Itoh ◽  
...  
Keyword(s):  
Michael Addition ◽  
In Silico ◽  
Addition Reaction ◽  
Single Point ◽  
Point Mutations ◽  
Unsaturated Ketone ◽  
Michael Addition Reaction ◽  
Beta Barrel ◽  
Cupin Superfamily ◽  
Single Point Mutations

Cupin superfamily proteins (TM1459) work as a macromolecular ligand framework with a double-stranded beta-barrel structure ligating to a Cu ion through histidine side chains. Variegating the first coordination sphere of TM1459 revealed that H52A and H54A/H58A mutants effectively catalyzed the diastereo- and enantio-selective Michael addition reaction of nitroalkanes to an α,β-unsaturated ketone. Moreover, in silico substrate docking signified C106N and F104W single-point mutations, which inverted the diastereoselectivity of H52A and further improved the stereoselectivity of H54A/H58A, respectively.

scholarly journals Synthesis, Antiproliferative Activity and Radical Scavenging Ability of 5-O-Acyl Derivatives of Quercetin

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1608
Author(s):  
Stephen Lo ◽  
Euphemia Leung ◽  
Bruno Fedrizzi ◽  
David Barker
Keyword(s):  
Antiproliferative Activity ◽  
Biological Activities ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Breast Cancer Cell Lines ◽  
Scavenging Activity ◽  
Plant Materials ◽  
Wide Range ◽  
Derivatives Of ◽  
Acyl Derivatives

Quercetin is a flavonoid that is found in many plant materials, including commonly eaten fruits and vegetables. The compound is well known for its wide range of biological activities. In this study, 5-O-acyl derivatives of quercetin were synthesised and assessed for their antiproliferative activity against the HCT116 colon cancer and MDA-MB-231 breast cancer cell lines; and their radical scavenging activity against the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical species. Four derivatives were found to have improved the antiproliferative activity compared to quercetin whilst retaining radical scavenging activity.

ChemInform Abstract: O-ACYL DERIVATIVES OF 2-PYRIDINALDOXIME

1978 ◽  
Vol 9 (52) ◽  
Author(s):  
P. YA. ROMANOVSKII ◽  
A. YU. KRIKIS ◽  
G. I. CHIPENS
Keyword(s):  
Derivatives Of ◽  
Acyl Derivatives
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