Synthesis Of 2-methyl Research Articles

The Synthesis of 2-Methyl-N-[(2-pyridine-2-yl-ethyl) carbamothioyl]benzamide-Silica Nanoparticles as a Reusable Catalyst for the Synthesis of Limonene Oxide from Limonene and Hydrogen Peroxide

The Synthesis of 2-Methyl-<i>N</i>-[(2-pyridine-2-yl-ethyl) carbamothioyl]benzamide-Silica Nanoparticles as a Reusable Catalyst for the Synthesis of Limonene Oxide from Limonene and Hydrogen Peroxide

Synthesis of 2-Methyl -3,4,5,10-Tetrahydro-Pyrrolo [3,2-A] Carbazole-Ethyl Carboxylate Derivatives and Evaluation of their Binding Affinity with CT-DNA

Synthesis of 2-Methyl -3,4,5,10-Tetrahydro-Pyrrolo [3,2-A] Carbazole-Ethyl Carboxylate Derivatives and Evaluation of their Binding Affinity with CT-DNA

ChemInform Abstract: SmI2‐Induced Cyclizations and Their Applications in Natural Product Synthesis

AbstractReview: 98 refs.

SmI2‐induced cyclizations and their applications in natural product synthesis

Since the isolation of brevetoxin-B, a red tide toxin, many bioactive marine natural products featuring synthetically challenging trans-fused polycyclic ether ring systems have been reported. We have developed SmI(2)-induced cyclization of beta-alkoxyacrylate with aldehyde, affording 2,6-syn-2,3-trans-tetrahydropyran (THP) or 2,7-syn-2,3-trans-oxepane with complete stereoselection, as a key reaction of efficient iterative and bi-directional strategies for the construction of these polycyclic ethers. This reaction is also applicable to the synthesis of 3-, 5-, and 6-methyl-THPs and 3,5-dimethyl-THP. The synthesis of 2-methyl- and 2,6-dimethyl-THPs was accomplished by means of a unique methyl insertion. Recently, the SmI(2)-induced cyclization was extended to similar reactions using beta-alkoxyvinyl sulfone and sulfoxide. Reaction of (E)- and (Z)-beta-alkoxyvinyl sulfone-aldehyde afforded 2,6-syn-2,3-trans- and 2,6-syn-2,3-cis- THPs, respectively. Reaction of (E)-beta-alkoxyvinyl (R)- and (S)-sulfoxides gave 2,6-anti-2,3-cis- and 2,6-syn-2,3-trans-THPs, respectively. Reaction of (Z)-beta-alkoxyvinyl (R)-sulfoxides gave 2,6-syn-2,3-cis-THP and an olefinic product, while that of (Z)-beta-alkoxyvinyl (S)-sulfoxide afforded a mixture of many products. These SmI(2)-induced cyclizations have been applied to the total syntheses of various natural products, including brevetoxin-B, mucocin, pyranicin, and pyragonicin. Synthetic studies on gambierol and maitotoxin are also introduced.

Synthesis of 2-methyl- and 2-methylenecyclobutane amino acids

An efficient and easy formal [2+2] cycloaddition (Michael–Dieckmann-type reaction) on methyl 2-acetamidoacrylate with ketene diethyl acetal gave the cyclobutane core. Two kinds of 2-substituted cyclobutane amino acids have been obtained from this compound by means of stereocontrolled interconversion of functional groups: 1-amino-2-methylcyclobutane-1-carboxylic acids (2,4-methanovalines) and 1-amino-2-methylenecyclobutane-1-carboxylic acid. The latter amino acid can be regarded as a restricted α-methyl-α-vinylglycine.

Conversion of ubiquinone-9 to ubiquinone-10 by use of the wittig reaction

1. Five- and seven-stage methods were developed for converting ubiquinone-9 and the dibenzyl ether of the corresponding hydroquinone to ubiquinone-10 by use of the Wittig reaction at the key stage; the overall yield was 2 and 17%, respectively. 2. The use of a pressure of 10–14 kbar was proposed for the direct synthesis of 2-methyl(hept-2-en-6-yl)triphenylphosphonium bromide.

Studies on the synthesis of 2-bromomethylimidazole nucleosides related to AICA-riboside [5-amino-1-(β-D-ribofuranosyl) imidazole-4-carboxamide

The synthesis of 2-methyl- and 2-bromomethyl-imidazole nucleoside derivatives, related to AICA-riboside, is described. Ethyl N-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl) acetimidate and ethyl N-(2,3-O-isopropylidene-β-D-ribofuranosyl) acetimidate, obtained from 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosylamine and 2,3-O-isopropylidene-D-ribofuranosylamine respectively, reacted with ethyl α-amino-α-cyanoacetate and α-amino-α-cyanoacetamide to give ethyl 5-amino-1-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)- and ethyl 5-amino-1-(2,3-O-isopropylidene-β-D-ribofuranosyl)-2-methyl-imidazole-4-carboxylate (3) and (5) and 5-amino-1-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)- and 5-amino-1-(2,3-O-isopropylidene-β-D-ribofuranosyl)-2-methylimidazole-4-carboxamide (4) and (6), respectively. Treatment of 5-amino-2-methylimidazole glucosides (3) and (4) with Ac2O and H3PO4 as catalyst followed by reaction with N-bromosuccimide (NBS) gave 5-(N,N-diacetylamino)-1-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)-2-bromomethylimidazole-4-carboxylate and the N-acetyl 4-carboxamide analogue, (18) and (17) respectively. Deisopropylidenation of the 5-amino-2-methylimidazole ribosides (5) and (6) followed by acetylation with Ac2O in the presence of 4-dimethylaminopyridine gave 5-(N,N-diacetylamino)-1-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-2-methylimidazole-4-carboxylate and -4-carboxamide (12) and (10). Treatment of (12) with NBS afforded ethyl 5-(N,N-diacetylamino)-1-(2,3,5-tri-O-acetyl-β-D-ribofuranoyl)-2-bromomethylimidazole-4-carboxylate (16). Structural assignments were made on the basis of 1H n.m.r. spectra.

Synthesis of 2-methyl-[2-acetamido-4- O-acetyl-6- O-benzyl-3 O-(2-butenyl)-1,2-dideoxy-α- d-glucopyrano]-[2,1- d]-2-oxazoline a versatile intermediate for the synthesis of complex oligosaccharides of bacterial cell-wall, human milk, and blood-group substances

2-Methyl-[2-acetamido-4- O-acetyl-6- O-benzyl-3- O (2-butenyl)-1,2-dideoxy-α- d-glucopyrano]-[2,1- d]-2-oxazoline ( 2), a glycosylating agent in which the three hydroxyl groups are blocked with protecting groups of differing “persistence”, is of utility in the synthesis of oligosaccharides containing highly branched 2-acetamido-2 deoxy- d-glucosyl residues, and it was synthesized in a ten-step sequence from 2-acetamido-2-deoxy- d-glucose via allyl 2-acetamido-4,6- O-benzylidene-2-deoxy-β- d-glucopyranoside ( 3)- Alkylation of 3 with 2-butenyl (crotyl) bromide, hydrolysis of the benzylidene acetal group, benzylation of the 6-hydroxyl group, and acetylation of the 4-hydroxyl group afforded allyl 2-acetamido-4- O-acetyl-6- O-benzyl-3- O-(2-butenyl)-2-deoxy-β- d-glucopyranoside ( 10). Treatment or 10 with chlorotris(triphenylphosphine)rhodium( l) gave mainly the corresponding 1-propenyl β-glycoside, which was converted into oxazoline 2 by the action of mercuric chloride-mercuric oxide in acetonitrile. Glycosylation of benzyl 2-acetamido-3,6-di- O-benzyl-2-deoxy-α- d-glucopyranoside with 2, and subsequent O-deacetylation at O-4′ gave a glycosyl acceptor, benzyl 2-acetamido-4- O-[2-acetamido-6- O-benzyl-3- O-(2-butenyl)-2-deoxy-β- d-glucopyranosyl]-3,6-di- O-benzyl-2-deoxy-α- d-glucopyranoside.

Mutants in the biosynthesis of isoleucine in a non-mating, non-sporulating brewing strain of Saccharomyces carlsbergensis

Mutants resistant to 2-amino-3-(methylthio)butanoic acid (thiaisoleucine) were selected from a non-mating, nonsporulating brewing strain of Saccharomyces carlsbergensis after treatment with N-methyl-N'-nitro-Nnitrosoguanidine. One closer studied mutant, C77-T70 had a threonine deaminase activity which was less sensitive to L-isoleucine than that of the parent strain. The inhibition with varying concentrations of L-isoleucine showed that part of the activity was as sensitive as that of the parent strain, suggesting that the mutant is heterozygous for a dominant change in the structural gene for threonine deaminase. Of twelve mutants selected on 25 mM-thiaisoleucine all are believed to have undergone a change similar to that of C77-T70, since their threonine deaminase activity was partly resistant to 1 mM-L-isoleucine like that of C77-T70. Four such mutants were compared to the parent strain for the production of fusel alcohols during aerobic growth in minimal medium. The synthesis of 2-methyl- 1 -butanol (D-amyl alcohol) was 2-5 times higher in the mutants than in the parent strain, while the syntheses in the mutants of 3-methyl-l-butanol (isoamyl alcohol) and 2-methyl-lpropanol (isobutanol) were similar or slightly reduced compared to the level found in the parent strain.

Synthesis of 2-methyl- and 2-ethylcyclotetradecanones

A method was proposed for the synthesis of the 2-methyl- and 2-ethylcyclotetradecanones from cyclododecanone via 1-morpholinocyclododecene.

ChemInform Abstract: SYNTHESIS OF 2‐METHYL‐ AND 2‐PHENYL‐5‐THIOPYRIDINES

AbstractAus den Pyridin‐Addukten (I) erhält man mit Disulfiden (II) die 5‐Thio‐2‐subst.‐pyridine (IIIa)‐(IIIc), die mit einem Äquivalent an m‐Chlorperbenzoesäure zu den (VI), die mit Alkoholat und Alkylierungsmitteln zu den 2‐substituierten 5‐Thiopyridinen (VII) reagieren.

Synthesis of 2-methyl and 2-phenyl-5-thiopyridines

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis of 2-methyl and 2-phenyl-5-thiopyridinesNeville Finch and C. W. GemendenCite this: J. Org. Chem. 1975, 40, 5, 569–574Publication Date (Print):March 1, 1975Publication History Published online1 May 2002Published inissue 1 March 1975https://doi.org/10.1021/jo00893a006RIGHTS & PERMISSIONSArticle Views186Altmetric-Citations18LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (967 KB) Get e-Alerts Get e-Alerts

Synthesis of 2-methyl(phenyl)-6-methyl-7-phenylindolisine and 2-methyl(phenyl)indolisino-[6,7-a]indene

Substituted indolisines were obtained from 2-methyl-, 2-ethoxymethyl-, and 2-phenoxymethyl-5-methyl-4-phenylpyridines. 3-Methyl-2-azafluorene was used in the syntheses of a four-ring condensed system — substituted indolisino[6,7-a]indene.

L, 9-Substituted fluorenes

The synthesis of 2-methyl (phenyl)-2, 3H-pyridazino-[4, 5, 6-m- l] fluorene-3-methylthionium methylsulfates and of derivatives with substituents in the fluorene ring, is described. Reaction of the latter with heterocyclic hydrazones, and also with compounds containing an active methylene or methyl group, gives cyanine dyes. The electronic spectra of the dyes are measured.

Synthesis of some N-substituted 2- and 3-methyl-4-piperidones

1. Convenient methods for the synthesis of 2-methyl- and 1,2-dimethyl-4-piperidones are proposed. 2. Several variants of the synthesis of 1-(1,1-dimethyl-2-propynyl)-2-methyl-4-piperidone were examined. 3. 1-p-Tolylsulfonyl derivatives of 4-piperidones do not undergo the amino-exchange reaction when heated with primary amines in presence of caustic alkalies.

Steroids—XCIV : Synthesis of 2-methyl- and 1,2-dimethyl-estrogens

2-Methyl-and 1,2-dimethyl-estrogens have been derived from 2-methyltestosterone via the Δ 1,4 and 1,4,6 compounds. Ultraviolet, rotatory and biological influences of alkyl substituents in the phenolic steroids series are discussed.

Communications - Steroids. LXXIII. Synthesis of 2-Methyl and 2,2-Dimethyl Hormone Analogs

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCommunications - Steroids. LXXIII. Synthesis of 2-Methyl and 2,2-Dimethyl Hormone AnalogsH. Ringold and G. RosenkranzCite this: J. Org. Chem. 1956, 21, 11, 1333–1335Publication Date (Print):November 1, 1956Publication History Published online27 February 2003Published inissue 1 November 1956https://doi.org/10.1021/jo01117a625RIGHTS & PERMISSIONSArticle Views140Altmetric-Citations18LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (367 KB) Get e-Alerts Get e-Alerts