Mn-Mediated Alpha-Radical Addition of Carbonyls to Olefins: Systematic Study, Scope, and Electrocatalysis

A systematic study of the manganese-mediated alpha-radical addition of carbonyl groups to olefins is presented. After an in-depth investigation of the parameters that govern the reaction, a first round of optimization allowed the development of a unified stoichiometric set of conditions which was subsequently assessed during the exploration of the scope. Due to observed limitations, the knowledge accumulated during the initial study was reengaged to quickly optimize promising substrates that were so far inaccessible under previously reported conditions. Altogether these results led to the creation of a predictive model based on the pKa of the carbonyl compound and both the substitution and geometry of the alkene coupling partner. Finally, a departure from the use of stoichiometric manganese was enabled through the development of a robust and practical electrocatalytic version of the reaction.

Laccase-Catalyzed Oxidation of Allylbenzene Derivatives: Towards a Green Equivalent of Ozonolysis

Laccase-based biocatalytic reactions have been tested with and without mediators and optimized in the oxidation of allylbenzene derivatives, such as methyl eugenol taken as a model substrate. The reaction primarily consisted in the hydroxylation of the propenyl side chain, either upon isomerization of the double bond or not. Two pathways were then observed; oxidation of both allylic alcohol intermediates could either lead to the corresponding α,β-unsaturated carbonyl compound, or the corresponding benzaldehyde derivative by oxidative cleavage. Such a process constitutes a green equivalent of ozonolysis or other dangerous or waste-generating oxidation reactions. The conversion rate was sensitive to the substitution patterns of the benzenic ring and subsequent electronic effects.

Revealing Unknown Controlled Substances and New Psychoactive Substances Using High-Resolution LC–MS-MS Machine Learning Models and the Hybrid Similarity Search Algorithm

High-resolution liquid chromatography (LC)–tandem mass spectrometry (MS-MS)-based machine learning models are constructed to address the analytical challenge of identifying unknown controlled substances and new psychoactive substances (NPSs). Using a training set composed of 770 LC–MS-MS barcode spectra (with binary entries 0 or 1) obtained generally by high-resolution mass spectrometers, three classification machine learning models were generated and evaluated. The three models are artificial neural network (ANN), support vector machine (SVM) and k-nearest neighbor (k-NN) models. In these models, controlled substances and NPSs were classified into 13 subgroups (benzylpiperazine, opiate, benzodiazepine, amphetamine, cocaine, methcathinone, classical cannabinoid, fentanyl, 2C series, indazole carbonyl compound, indole carbonyl compound, phencyclidine and others). Using 193 LC–MS-MS barcode spectra as an external test set, accuracy of the ANN, SVM and k-NN models were evaluated as 72.5%, 90.0% and 94.3%, respectively. Also, the hybrid similarity search (HSS) algorithm was evaluated to examine whether this algorithm can successfully identify unknown controlled substances and NPSs whose data are unavailable in the database. When only 24 representative LC–MS-MS spectra of controlled substances and NPSs were selectively included in the database, it was found that HSS can successfully identify compounds with high reliability. The machine learning models and HSS algorithms are incorporated into our home-coded artificial intelligence screener for narcotic drugs and psychotropic substances standalone software that is equipped with a graphic user interface. The use of this software allows unknown controlled substances and NPSs to be identified in a convenient manner.

Study on Thermal Accumulation Risk of e-Cigarettes According to Heating Coil Shape

In this study, factors affecting the degree of heat accumulation and amount of carbonyl compound production of e-cigarettes were studied. Structurally, e-cigarettes consist of an electronic circuit device and a cartomizer. The liquid solution of the e-cigarette is vaporized by a coil in the cartomizer, where heat accumulation and carbonyl compound production occur. The relationship between the two were analyzed according to the shape of the coil. X-ray images of the coil shapes within the cartomizer were obtained and classified according to the relative widths of the coils. The degree of heat accumulation and amount of carbonyl compound generation were examined via inhale and exhale tests. The relationships among the relative width of the coil, degree of heat accumulation, and amount of carbonyl compound generation were derived. For optimal design of the cartomizer, it is suggested that the relative width of the coil be set to to 5 or more.

A Review on Chemical Constituents, Traditional Uses, Pharmacological Studies of Zanthoxylum armatum (Rutaceae)

Zanthoxylum armatum used as a medicine from ancient time for cure of various diseases such as toothache and problems related to tooth, asthma, used for gum bleeding, fever, dyspepsia, and tonics etc. Phytochemistry, pharmacological activities, diseases, traditional uses etc are explained in this review article .This article have information of the Z. armatum which may have Phytochemistry, pharmacological activities, diseases, traditional uses etc. Some latest info of Phytochemistry, pharmacological activities, diseases, traditional uses may show clearance in review. Different activities of various diseases known as antioxidants, antinociceptive, antifungal, antinflammtory, hepatoprotective, pesticides, anthelminitic, antiproliferative etc including chemical constituents like resins, 1-alphaphellandrene, linalool, carbonyl compound, methyl n-nonylketone. Linalyl acetate, sesquiterpene, hydrocarbon, tricosaine, dictamine, fragarine, magnoflorine, skimmianine, xanthoplanine. It is expected that more investigation on plant can be done. This review article is helpful to get various important evidence regarding the plant Zanthoxylum armatum which will works as key point for the future investigation. Keywords: Z.armatum, Phytochemistry, traditional uses, pharmacological activities.

Derivatized volatile organic compound characterization of Friulano wine from Collio (Italy–Slovenia) by HS-SPME-GC-MS and discrimination from other varieties by chemometrics

PurposeMethods to assess the authenticity and traceability of wines have been extensively studied as enhancers of food quality, allowing producers to obtain market recognition and premium prices. Among analytical techniques, the volatilome profile attained by gas chromatography coupled with mass spectrometry is acquiring more and more attention by the scientific community, together with the use of chemometricsDesign/methodology/approachThe volatilome profile of three varieties of blanc wines from the Collio area (namely Ribolla Gialla, Malvasia and Friulano) between Italy and Slovenia, was determined by head space-solid phase micro extraction-gas chromatography-mass spectrometry, enhancing the carbonyl compounds identification with O-(2, 3, 4, 5, 6-pentafluorobenzyl)-hydroxylamine with the aim of identifying the autochthonous Friulano variety.FindingsA two-step chemometric approach based on an unsupervised technique (PCA) followed by a supervised one (PLS-DA) allowed to identify possible markers for discriminating the Friulano Collio variety from the others, in particular two chemical classes were identified by PCA (ketones and long chain esters). PLS-DA showed 87% accuracy in classification. A correct classification (i.e. non-Friulano Collio) of a group of wines obtained from the same grape variety but produced in an extra-Collio area was obtained as well. The results confirmed the benefits of using a derivatization step prior to volatile organic compounds analysis.Research limitations/implicationsAmong methods to assess the authenticity and traceability of wines, volatilome profile of wines determined by head space-solid phase micro extraction-gas chromatography-mass spectrometry, enhanced by the carbonyl compound identifications with O-(2, 3, 4, 5, 6-pentafluorobenzyl)-hydroxylamine, may have a key role in conjunction with chemometrics and, in particular with principal component analysis and partial least square discriminant analysis.Practical implicationsAmong methods to assess the authenticity and traceability of Friulano wine, volatilome profile of wines determined by head space-solid phase micro extraction-gas chromatography-mass spectrometry, enhanced by the carbonyl compound identifications with O-(2, 3, 4, 5, 6-Pentafluorobenzyl)Hydroxylamine hydrochloride, may have a key role in conjunction with chemometrics.Originality/valueFew works investigated both wine traceability with a volatilome enhancer and chemometrics of the Friulano wine variety obtaining such an improvement in this wine variety discrimination.