Tag: M.W=150-200

Dinca, Emanuela; Hartmann, Philip; Smrcek, Jakub; Dix, Ina; Jones, Peter G.; Jahn, Ullrich published the artcile< General and Efficient α-Oxygenation of Carbonyl Compounds by TEMPO Induced by Single-Electron-Transfer Oxidation of Their Enolates>, Formula: C6H10O5, the main research area is alpha oxygenated carbonyl compound preparation; regioselective oxygenation carbonyl compound single electron transfer oxidation; stable free radical TEMPO coupling carbonyl compound; piperidinyloxy ketone ester amide acid nitrile preparation; enolate aggregate influence oxygenation reactions significantly; chemoselective reduction piperidinyloxy compound; hydroxy alpha carbonyl compound preparation; monoprotected diol preparation; amino alc protected preparation.

A generally applicable method for the synthesis of protected α-oxygenated carbonyl compounds is reported. It is based on the single-electron-transfer oxidation of easily generated enolates to the corresponding α-carbonyl radicals. Coupling with the stable free radical TEMPO provides α-(piperidinyloxy) ketones, esters, amides, acids or nitriles in moderate-to-excellent yields. Enolate aggregates influence the outcome of the oxygenation reactions significantly. Competitive reactions have been analyzed and conditions for their minimization are presented. Chemoselective reduction of the products led to either N-O bond cleavage to α-hydroxy carbonyl compounds or reduction of the carbonyl functionality to monoprotected 1,2-diols or O-protected amino alcs.

European Journal of Organic Chemistry published new progress about Aldehydes Role: RCT (Reactant), RACT (Reactant or Reagent) (enolization and TEMPO-induced single-electron-transfer oxidation of). 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Formula: C6H10O5.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Listowsky, Irving; Avigad, Gad; Englard, Sasha published the artcile< Conformational equilibria and stereochemical relations among carboxylic acids>, HPLC of Formula: 617-55-0, the main research area is acyclic acid conformation; conformation acyclic acid; circular dichroism acyclic acid.

The CO spectra of certain acyclic carboxylic acids were surveyed in an effort to study their conformation in solution In aqueous solution the spectra of many α-hydroxy acids were characterized by two overlapping ellipticity bands; a weak one in the 240-mμ spectral region and a more intense one of opposite sign near 210 mμ. At elevated temperatures or in solvents of low dielec. constant, the band of longer wavelength increased in intensity with an attendant decrease in the short-wavelength band. These properties are compatible with the presence of two structural species in equilibrium, and could be related to the contributions of specific rotational isomers of the acids. Conformations with the hydroxyl and carbonyl groups in an eclipsed alignment are designated as preferred. In contrast to the α-hydroxy acids, carboxylic acids with α-alkyl substituents generally showed only a single dichroic band centered near 210 mμ. In general, coplanarity of the carboxyl group and α-substituents was assumed, and interpretations in terms of the preferred orientation of substituents adjacent to the carboxyl group are suggested. The proposed population of rotational isomers was consistent with the observed effects of solvent polarity, temperature, polarity of substituents, and predicted steric interactions. An empirical rule relating the sign of ellipticity and the conformation of these classes of carboxylic acids was applied.

Journal of Organic Chemistry published new progress about Acids Role: PRP (Properties). 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, HPLC of Formula: 617-55-0.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Muraoka, Osamu; Toyooka, Naoki; Ohshima, Yumiko; Narita, Norihiko; Momose, Takefumi published the artcile< Synthesis of natural (S)-(-)-tulipalin B starting from L-malic acid as a chiral pool>, Recommanded Product: (S)-Dimethyl 2-hydroxysuccinate, the main research area is tulipalin B total synthesis enantioselectivity; malic acid chiral synthon tulipalin B.

Naturally occurring tulipalin B (I) was prepared enantioselectively from chiral synthon L-malic acid (II) in 15% yield.

Heterocycles published new progress about Chiral synthons. 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Recommanded Product: (S)-Dimethyl 2-hydroxysuccinate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Strazzolini, Paolo; Verardo, Giancarlo; Gorassini, Fausto; Giumanini, Angelo G. published the artcile< Orientation effect of side chain substituents in aromatic substitution. Induced ortho nitration>, Application In Synthesis of 30095-98-8, the main research area is ortho nitration toluene derivative regiochem; benzeneacetic acid ortho nitration.

The presence of a free carboxyl or ester function on the α-carbon of toluene induces the nitration of the Ph ring in the ortho position at or above the statistical value (chaperon effect), when pure HNO3 is used in CH2Cl2 solution This is at variance with the results of classical nitration in H2SO4, where p-nitration predominates by far and m-nitration occurs to a remarkable extent. The new finding is explained in terms of precomplex formation.

Bulletin of the Chemical Society of Japan published new progress about Nitration. 30095-98-8 belongs to class esters-buliding-blocks, and the molecular formula is C9H9NO4, Application In Synthesis of 30095-98-8.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Roy, Sourav; Kumar, Gourav; Chatterjee, Indranil published the artcile< Photoinduced Diverse Reactivity of Diazo Compounds with Nitrosoarenes>, HPLC of Formula: 94-02-0, the main research area is nitrosobenzene aralkyl diazoacetate oxygen transfer photochem; alkyl oxo aryl acetate preparation; nitrosoarene aralkyl diazoacetate regioselective cycloaddition photochem; aralkyl oxazetidinone preparation.

A diverse reactivity of diazo compounds with nitrosobenzene in an oxygen-transfer process and a formal [2 + 2] cycloaddition was reported. Nitosoarene was exploited as a mild oxygen source to oxidize an in-situ generated carbene intermediate under visible-light irradiation UV-light-mediated in-situ generated ketenes reacted with nitosobenzenes to deliver oxazetidine derivatives These operationally simple processes exemplify a transition-metal-free and catalyst-free protocol to give structurally diverse α-ketoesters or oxazetidines.

Organic Letters published new progress about [2+2] Photocycloaddition reaction. 94-02-0 belongs to class esters-buliding-blocks, and the molecular formula is C11H12O3, HPLC of Formula: 94-02-0.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Mattingly, Stephanie J.; Wuest, Frank; Schirrmacher, Ralf published the artcile< Synthesis of 2-Fluoroacetoacetic Acid and 4-Fluoro-3-hydroxybutyric Acid>, Formula: C6H10O5, the main research area is fluoroacetoacetic acid preparation; acetoacetate ester fluorination; fluoro hydroxybutyric acid preparation; epoxyester fluorination.

The synthesis of two new fluorinated butyric acids (and three related esters) these were derivatives of the metabolites acetoacetic acid and 3-hydroxybutyric acid. 4-Fluoro-3-hydroxybutyric acid was synthesized from epoxy ester precursors via ring opening by triethylamine trihydrofluoride. 2-Fluoroacetoacetic acid was prepared by electrophilic fluorination of an acid-labile β-keto ester. The gradual pH-dependent decarboxylation of 2-fluoroacetoacetic acid was investigated by 19F NMR spectroscopy.

Synthesis published new progress about Acid halides Role: SPN (Synthetic Preparation), PREP (Preparation). 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Formula: C6H10O5.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Drouillat, Bruno; Poupardin, Olivia; Bourdreux, Yann; Greck, Christine published the artcile< Diastereoselective syntheses of α-amino-β-hydroxyesters precursors of the ribosyl-diazepanone core of the liposidomycins>, Recommanded Product: Methyl 4,4-dimethoxy-3-oxobutanoate, the main research area is amino hydroxyester glycoside chiral synthon preparation liposidomycin; ribosyl hydroxy amino ester diastereoselective preparation.

The diastereoselective syntheses of the O-protected ribosyl-β-hydroxy-α-amino esters, precursors of α-ribosyl-diazepanone core analogs of the liposidomycins, resp., from the β-ketoesters are described. The anti relationship between the two adjacent aminated and hydroxylated carbons was controlled by sequential hydrogenation of the β-ketoesters in the presence of chiral ruthenium catalysts and electrophilic amination of the resulting β-hydroxyesters.

Tetrahedron Letters published new progress about Chiral synthons. 60705-25-1 belongs to class esters-buliding-blocks, and the molecular formula is C7H12O5, Recommanded Product: Methyl 4,4-dimethoxy-3-oxobutanoate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Shim, Jae Ho; Nam, Si Hun; Kim, Byeong-Seon; Ha, Deok-Chan published the artcile< Organocatalytic asymmetric Michael addition of ketones to α, β-unsaturated nitro compounds>, Related Products of 19241-24-8, the main research area is ketone unsaturated nitro compound organocatalytic asym Michael addition.

An organic catalyst “”(R, R)-1,2-diphenylethylenediamine(DPEN) derivative”” was developed as a chiral bifunctional organocatalyst and applied for asym. Michael additions of aromatic ketones to trans-β-nitroalkene compounds under neutral conditions. The isopropyl-substituted thiourea catalyst in neutral condition provides high chem. yield and enantioselectivities (ee) (up to 96% yield, 98% ee).

Catalysts published new progress about Michael reaction catalysts, stereoselective. 19241-24-8 belongs to class esters-buliding-blocks, and the molecular formula is C11H13NS, Related Products of 19241-24-8.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Cerda, Matthew M.; Mancuso, Jenna L.; Mullen, Emma J.; Hendon, Christopher H.; Pluth, Michael D. published the artcile< Use of Dithiasuccinoyl-Caged Amines Enables COS/H2S Release Lacking Electrophilic Byproducts>, SDS of cas: 19241-24-8, the main research area is dithiasuccinoyl carbonyl sulfide hydrogen sulfide release; bioorganic chemistry; carbonyl sulfide; hydrogen sulfide; reactive sulfur species.

The enzymic conversion of carbonyl sulfide (COS) to hydrogen sulfide (H2S) by carbonic anhydrase has been used to develop self-immolating thiocarbamates as COS-based H2S donors to further elucidate the impact of reactive sulfur species in biol. The high modularity of this approach has provided a library of COS-based H2S donors that can be activated by specific stimuli. A common limitation, however, is that many such donors result in the formation of an electrophilic quinone methide byproduct during donor activation. As a mild alternative, we demonstrate here that dithiasuccinoyl groups can function as COS/H2S donor motifs, and that these groups release two equivalent of COS/H2S and uncage an amine payload under physiol. relevant conditions. Addnl., we demonstrate that COS/H2S release from this donor motif can be altered by electronic modulation and alkyl substitution. These insights are further supported by DFT investigations, which reveal that aryl and alkyl thiocarbamates release COS with significantly different activation energies.

Chemistry – A European Journal published new progress about Free energy of activation. 19241-24-8 belongs to class esters-buliding-blocks, and the molecular formula is C11H13NS, SDS of cas: 19241-24-8.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Patane, Emanuele; Pittala, Valeria; Guerrera, Francesco; Salerno, Loredana; Romeo, Giuseppe; Siracusa, Maria Angela; Russo, Filippo; Manetti, Fabrizio; Botta, Maurizio; Mereghetti, Ilario; Cagnotto, Alfredo; Mennini, Tiziana published the artcile< Synthesis of 3-Arylpiperazinylalkylpyrrolo[3,2-d]pyrimidine-2,4-dione Derivatives as Novel, Potent, and Selective α1-Adrenoceptor Ligands>, COA of Formula: C7H10N2O2, the main research area is pyrrolopyrimidine dione piperazinylalkyl preparation selective adrenoceptor ligand QSAR.

Novel compounds I [X = (CH2)2, (CH2)3; R1 = H, Ph, 2-ClC6H4, 4-MeC6H4, etc.; R2 = 2-MeOC6H4, 4-MeOC6H4, 2-ClC6H4], characterized by a pyrrolo[3,2-d]pyrimidine-2,4-dione (PPm) system connected through an alkyl chain to a phenylpiperazine (PPz) residue, were designed as structural analogs of the α1-adrenoceptor (α1-AR) ligand RN5. In this new series of derivatives, the indole nucleus of RN5 was replaced by an arylpyrrolo moiety. Several structural modifications were performed on the PPm and PPz moieties and the connecting alkyl chain. These compounds were synthesized and tested in radioligand binding experiments where many of them showed interesting binding profiles. Some compounds, including I [X = (CH2)2; R1 = 2-ClC6H4, 4-ClC6H4, 4-MeC6H4; R2 = 2-ClC6H4], displayed substantial α1-AR selectivity with respect to serotoninergic 5-HT1A and dopaminergic D1 and D2 receptors. Two different mol. modeling approaches (pharmacophoric mapping and quant. structure-affinity relationship anal.) have been applied to rationalize, at a quant. level, the relationships between affinity toward α1-ARs and the structure of the studied compounds Several QSAR models have been reported and described, accounting for the influence of various mol. portions on such affinity data.

Journal of Medicinal Chemistry published new progress about Pharmacophores. 252932-48-2 belongs to class esters-buliding-blocks, and the molecular formula is C7H10N2O2, COA of Formula: C7H10N2O2.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics