Heterocyclic Building Blocks-Oxazolidine

Viegas, Marcelo Caldeira’s team published research in Quimica Nova in 30 | CAS: 20662-83-3

Quimica Nova published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C2H2N4O2, Safety of 4,5-Dimethyloxazole.

Viegas, Marcelo Caldeira published the artcileUse of the linear retention index for characterization of volatile compounds in soluble coffee using GC-MS and an HP-innowax column, Safety of 4,5-Dimethyloxazole, the publication is Quimica Nova (2007), 30(8), 2031-2034, database is CAplus.

Due to the complexity of the soluble coffee matrix, complete identification of flavor components should not be based on GC-MS anal. only. The linear retention index (LRI) is frequently used to give support to mass spectral data. Volatile compounds in dry lyophilized soluble Arabic coffee samples were characterized by head-space (solid-phase microextraction) GC-MS; the LRI values were determined with the HP-Innowax column. The combined method significantly increased the reliability of identifying the volatile compounds; 88 volatile compounds were identified.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Piloty, Markus’s team published research in Zeitschrift fuer Lebensmittel-Untersuchung und -Forschung in 168 | CAS: 20662-83-3

Zeitschrift fuer Lebensmittel-Untersuchung und -Forschung published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, COA of Formula: C5H7NO.

Piloty, Markus published the artcileInvestigations on the reaction of amino acids with α-dicarbonyl compounds. II. Volatile products of the reaction of amino acids with diacetyl (2,3-butanedione), COA of Formula: C5H7NO, the publication is Zeitschrift fuer Lebensmittel-Untersuchung und -Forschung (1979), 168(5), 374-80, database is CAplus.

Glycine [56-40-6], α-alanine [56-41-7], β-alanine [107-95-9], phenylalanine [63-91-2], glycylalanine [3695-73-6], and NH₃ were reacted with diacetyl [431-03-8], in an aqueous medium. In addition to several N-free compounds, some nitrogenous heterocyclic products belonging to the classes oxazoles, pyrazines, pyrroles, and pyridines were identified. The pyridine derivatives have not previously been described in the literature. Spectral data are given and possible mechanisms of formation discussed in relation to food aroma.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Ribeiro, J. S.’s team published research in Analytica Chimica Acta in 634 | CAS: 20662-83-3

Analytica Chimica Acta published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, SDS of cas: 20662-83-3.

Ribeiro, J. S. published the artcilePrediction of sensory properties of Brazilian Arabica roasted coffees by headspace solid phase microextraction-gas chromatography and partial least squares, SDS of cas: 20662-83-3, the publication is Analytica Chimica Acta (2009), 634(2), 172-179, database is CAplus and MEDLINE.

Volatile compounds in fifty-eight Arabica roasted coffee samples from Brazil were analyzed by SPME-GC-FID and SPME-GC-MS, and the results were compared with those from sensory evaluation. The main purpose was to investigate the relationships between the volatile compounds from roasted coffees and certain sensory attributes, including body, flavor, cleanliness and overall quality. Calibration models for each sensory attribute based on chromatog. profiles were developed by using partial least squares (PLS) regression. Discrimination of samples with different overall qualities was done by using partial least squares-discriminant anal. (PLS-DA). The alignment of chromatograms was performed by the correlation optimized warping (COW) algorithm. Selection of peaks for each regression model was performed by applying the ordered predictors selection (OPS) algorithm in order to take into account only significant compounds The results provided by the calibration models are promising and demonstrate the feasibility of using this methodol. in online or routine applications to predict the sensory quality of unknown Brazilian Arabica coffee samples. According to the PLS-DA on chromatog. profiles of different quality samples, compounds 3-methypropanal, 2-methylfuran, furfural, furfuryl formate, 5-methyl-2-furancarboxyaldehyde, 4-ethylguaiacol, 3-methylthiophene, 2-furanmethanol acetate, 2-ethyl-3,6-dimethylpyrazine, 1-(2-furanyl)-2-butanone and three others not identified compounds can be considered as possible markers for the coffee beverage overall quality.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Lehmann, Johannes’s team published research in Organic Letters in 15 | CAS: 72571-06-3

Organic Letters published new progress about 72571-06-3. 72571-06-3 belongs to oxazolidine, auxiliary class Oxazole,Bromide,Benzene, name is 5-(4-Bromophenyl)oxazole, and the molecular formula is C9H6BrNO, Recommanded Product: 5-(4-Bromophenyl)oxazole.

Lehmann, Johannes published the artcileThe Kondrat’eva Reaction in Flow: Direct Access to Annulated Pyridines, Recommanded Product: 5-(4-Bromophenyl)oxazole, the publication is Organic Letters (2013), 15(14), 3550-3553, database is CAplus and MEDLINE.

A continuous flow inverse-electron-demand Kondrat’eva reaction has been developed that provides direct access to cycloalka[c]pyridines from unactivated oxazoles and cycloalkenes. The cycloadditions of both unactivated alkenes and deactivated oxazoles are promoted in continuous flow at elevated temperatures and pressures (230 °C, 750psi). E.g., reaction of 5-phenyloxazole and cyclopentene in presence of TFA gave 55% 4-phenyl-6,7-dihydro-5H-cyclopenta[c]pyridine (I). Annulated pyridines obtained by this one-step process are valuable scaffolds for medicinal chem.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Al-Duri, B.’s team published research in Journal of Supercritical Fluids in 116 | CAS: 20662-83-3

Journal of Supercritical Fluids published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, Category: oxazolidine.

Al-Duri, B. published the artcileSupercritical water oxidation (SCWO) for the removal of N-containing heterocyclic hydrocarbon wastes. Part I: Process enhancement by addition of isopropyl alcohol, Category: oxazolidine, the publication is Journal of Supercritical Fluids (2016), 155-163, database is CAplus.

The present work investigates the destruction of nitrogen-containing heterocyclic hydrocarbons frequently encountered in hazardous wastes by supercritical water oxidation (SCWO), with focus on the process enhancement using iso-Pr alc. (IPA) as co-fuel. 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) was selected for SCWO in a continuous plug flow reactor, under a range of temperatures (400-525°C), oxidant ratios nSR (0.8-2.0) and IPA/DBU ratios (0.5-3.5). Exptl. results were presented in terms of total organic carbon (TOC) removal %, and nitrogenous products yield %. Based on GC-MS anal., a free radical reaction mechanism for SCWO of DBU was proposed. Results showed that temperature was the predominant factor to influence the rate of DBU oxidation, while oxidant ratio (nSR) significantly affected the N speciation in the exit stream. IPA addition had a significant impact on shifting recalcitrant aqueous ammonia NH⁺₄ in the liquid stream to gaseous nitrogen. It also increased TOC removal% (DBU + IPA) due to the increased free radicals produced by IPA oxidation

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Bogdanov, V. S.’s team published research in Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya in | CAS: 20662-83-3

Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, Application In Synthesis of 20662-83-3.

Bogdanov, V. S. published the artcileCarbon-13, nitrogen-14, and proton NMR spectra and effects of substituents in oxazoles, Application In Synthesis of 20662-83-3, the publication is Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya (1980), 305-16, database is CAplus.

¹³C NMR data were obtained for 40 oxazoles; ¹H and ¹⁴N data were obtained for 6 and 11 of these, resp. The following linear correlations were made: chem. shift (δ) for C-2 with δ for C-4, δ for C-4 with δ for C-5, δ for C-2 with δ for H-2, δ for C-4 with δ for H-4, δ for C-5 with the electronegativity of the substituent at C-5, and ¹³C δ values for 4,5-disubstituted oxazole with those for 1,2-disubstituted benzenes. An additive method for calculating ¹³C δ values was tested successfully. The effect of substituents on various coupling constants was also determined

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Hay, Duncan A.’s team published research in Tetrahedron Letters in 52 | CAS: 20662-83-3

Tetrahedron Letters published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, Application In Synthesis of 20662-83-3.

Hay, Duncan A. published the artcileA flexible synthesis of C-6 and N-1 analogues of a 4-amino-1,3-dihydroimidazo[4,5-c]pyridin-2-one core, Application In Synthesis of 20662-83-3, the publication is Tetrahedron Letters (2011), 52(44), 5728-5732, database is CAplus.

A flexible route which enables access to derivatives of 4-amino-1,3-dihydroimidazo[4,5-c]pyridin-2-ones is described. Issues of selectivity, reaction safety, and low yields in original routes are overcome with the key improvements to the route, including a Negishi cross-coupling and use of a carbamate as a protecting group and intrinsic carbonyl source. The new route enables variation of C-6 and N-1 substituents.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Ferreira, Jasmin’s team published research in Organic & Biomolecular Chemistry in 2016 | CAS: 4042-43-7

Organic & Biomolecular Chemistry published new progress about Alkylation. 4042-43-7 belongs to class oxazolidine, name is (R)-4-Methyloxazolidin-2-one, and the molecular formula is C4H7NO2, Recommanded Product: (R)-4-Methyloxazolidin-2-one.

Ferreira, Jasmin published the artcileChemoselective room temperature E1cB N-N cleavage of oxazolidinone hydrazides from enantioselective aldehyde α-hydrazination: synthesis of (+)-1,4-dideoxyallonojirimycin, Recommanded Product: (R)-4-Methyloxazolidin-2-one, the main research area is enantioselective aldehyde hydrazination oxazolidinone hydrazide cleavage deoxyallonojirimycin synthesis; E1cB elimination alkylation enantioselective synthesis deoxyallonojirimycin oxazolidinone hydrazide bromomalonate.

Room temperature E1cB N-N cleavage of oxazolidinone hydrazides via N-alkylation with di-Et bromomalonate and potassium or cesium carbonate as base in acetonitrile is presented. The new method has a much improved chemoselectivity, which is illustrated by a concise total synthesis of the piperidine iminosugar (+)-1,4-dideoxyallonojirimycin.

Referemce:
Oxazolidine – Wikipedia,
Oxazolidine | C3H7NO – PubChem

Koivusalo, M.’s team published research in Biochemische Zeitschrift in 1965 | CAS: 4042-43-7

Biochemische Zeitschrift published new progress about Mitochondria. 4042-43-7 belongs to class oxazolidine, name is (R)-4-Methyloxazolidin-2-one, and the molecular formula is C4H7NO2, Related Products of oxazolidine.

Koivusalo, M. published the artcileOn the yield of respiratory-chain phosphorylation, Related Products of oxazolidine, the main research area is .

The P/O ratio of guinea-pig heart sarcosomes oxidizing glutamate was 2.42-2.87 (mean 2.63) when the incubation procedure of Smith and Hansen (CA 61, 2077h) was followed. The steady-state P/O ratio of rat-liver mitochondria oxidizing glutamate, under the conditions used by Gurban and Cristea (Rev. Roumaine Biochem. 1(1), 51-7(1964)), was 2.5. Preceding this steady-state value there was a burst of phosphorylation in the 1st few minutes, which was not accompanied by a corresponding increase in O uptake. The true yield of oxidative phosphorylation was given by the ratios of the rates of phosphorylation and oxidation when the steady state was achieved, and that the burst of phosphorylation was related to the previous history of the mitochondria. The cause of the burst was not known.

Referemce:
Oxazolidine – Wikipedia,
Oxazolidine | C3H7NO – PubChem

Wang, Linqing’s team published research in Chinese Chemical Letters in 2022-09-30 | CAS: 4042-43-7

Chinese Chemical Letters published new progress about Dearomatization. 4042-43-7 belongs to class oxazolidine, name is (R)-4-Methyloxazolidin-2-one, and the molecular formula is C4H7NO2, Formula: C4H7NO2.

Wang, Linqing published the artcileA tandem asymmetric oxidation-oxa-Michael sequence for dearomatization of β-naphthols, Formula: C4H7NO2, the main research area is spiro furan naphthalene preparation enantioselective; naphthol phenyl benzooxazirenoisothiazole dioxide hydroxylative dearomatization tandem.

A catalytic asym. hydroxylative dearomatization reaction was disclosed, and the products could smoothly transform into spiroannulation adducts I [R = H, Me, Et, etc.; R1 = Me, Et, Bn] by simply treating with a base under mild conditions. Novel in-situ generated magnesium catalytic methods were developed by application of combinational ligands. Related concise transformations of the spiroannulation adducts were carried out.

Referemce:
Oxazolidine – Wikipedia,
Oxazolidine | C3H7NO – PubChem