40 research outputs found
Ni(II) complex of bisthiophosphorylated thiourea prepared from the Betti base
© 2017, Pleiades Publishing, Ltd. The interaction between bisthiophosphorylated thiourea with nickel(II) nitrate in the presence of potassium tert-butylate has afforded NiL 2 complex with square-planar configuration of the nickel(II) ion and the 1,3-N,S-coordination of the trans-positioned similar heteroatoms
Synthesis of α-amino phosphonates by diastereoselective addition of diethyl phosphite sodium salt to aldimines derived from Betti base
© 2016A diastereoselective (de 80–92%) synthesis of α-amino phosphonates was accomplished by reaction of diethyl phosphite sodium salt with 3-R-1-phenyl-2,3-dihydro-1H-naphth[1,2-e]-[1,3]oxazines being the products of aminoacetalization of aldehydes with 1-(α-aminobenzyl)-2-naphthol (Betti base)
Betti base in the synthesis of chiral bisphosphorylated thioureas
© 2017, Pleiades Publishing, Ltd. Phosphorylation of a naphthol hydroxy group of thiophosphorylated thiourea obtained by reaction of diethyl thiophosphoryl isothiocyanate with 1-(α-aminobenzyl)-2-naphthol (Betti base) afforded a number of chiral bisphosphorylated thioureas. Molecular structure of the obtained compounds was studied by single crystal X-ray diffraction. The capacity of the studied compounds for dimerization due to the intermolecular N–HS hydrogen bonding was revealed
A new synthetic route to chiral 3-aryl-5-ethyl-1,4,2-oxazaphosphorines
© 2018 Diastereoselective synthesis of racemic and enantiopure 3-aryl-5-ethyl-1,4,2-oxazaphosphorines, including those bearing phenolic hydroxyl groups in the exocyclic aromatic fragment, was implemented by the reaction of imines derived from (±)-and (R)-(−)-2-aminobutan-1-ol and (hydroxy)benzaldehydes with triethyl phosphite and trifluoroacetic acid, followed by the one-pot dealkylation of the intermediate esters
Phosphorylation of betti base with diethyl chlorophosphate
© 2016, Pleiades Publishing, Ltd.Phosphoric acid derivatives containing chiral Betti base fragment were synthesized by reacting racemic and enantiopure N-Boc-protected 1-(α-aminobenzyl)-2-naphthols with diethyl chlorophosphate followed by deprotection
Chiral thiophosphorylated thioureas: Synthesis, structure, and cyclization reaction
© 2014 Wiley Periodicals, Inc. A number of chiral racemic and enanthiopure thiophosphorylated thioureas were synthesized by the reaction of 2-aminobutan-1-ol and 1-(a-aminobenzyl)-2-naphthol with O,O-diethyl thiophosphoryl isothiocyanate. It was found that such thioureas undergo the cyclization reaction under basic conditions with hydrogen sulfide elimination and the formation of thiophosphorylated oxasines. XRay single crystal diffraction revealed that the structure of thiourea is close to the prereaction state of the cyclization reaction
Phosphorylation of Betti Base with Bis(diethylamino)phosphoryl Chloride
© 2018, Pleiades Publishing, Ltd. The reaction of bis(diethylamino)phosphoryl chloride with N-Boc-protected 1-(α-aminobenzyl)-2- naphthol (Betti base) proceeded via O-phosphorylation of the phenolic OH group to form the target product as trifluoroacetate salt. The latter reacted with O,O-diethyl thiophosphorylisothiocyanate to give thiourea bearing a chiral Betti base fragment
The effect of COVID-19 on the digestive system
This article describes the symptoms associated with the digestive system that can be caused by a new coronavirus infection.В данной статье описаны симптомы, связанные с пищеварительной системой, которые могут быть вызваны новой коронавирусной инфекцией
Сортировка плодов авокадо по гиперспектральным изображениям
The paper shows the use of the methods of hyperspectral imaging (HSI) in a range of 400–1000 nm and multivariate analysis for sorting Hass avocado fruits. The decomposition of the data matrix of HSIs of avocado fruits was carried out using the principle component analysis. The reflection bands in the visible and near-infrared spectral regions interrelated with the process of maturation and the moisture content of avocado fruits were revealed. It has been established that visualization upon avocado inline sorting by moisture is possible when using factor loadings as pseudo-color. Calibration models for determination of moisture and dry matter of avocado fruits were built based on the data of moisture measurement and hyperspectral images. The matrix of spectral data was formed by two methods: random selection of spectral signatures of HSIs from the whole surface of fruits or the image surface of HSIs of fruits (initial HSIs) as a region of interest (ROI). Based on the data of moisture measurement and selection of spectral signatures of hyperspectral images, calibration models were built for detection of moisture and dry matter of avocado fruits. Using sequential simulation by the projection to latent structures (PLS) method, accurate calibration models were developed to detect moisture (RP2 = 0.89) and dry matter (RP2 = 0.92) in the composition of avocado fruits. When building calibration models by the initial HSIs, models were obtained to predict moisture (RС2 = 0.99) and dry matter (RС2 = 0.99) in the composition of avocado fruits. It is proposed to use calibration models by the initial HSIs to determine moisture and dry matter in the intervals of the acceptable values according to the acting standard UNECE STANDARD FFV-42:2019.Показано применение методов гиперспектрального изображения (HSI) в диапазоне 400–1000 нм и многомерного анализа для сортировки плодов авокадо Хасс. Методом главных компонент осуществлена декомпозиция матрицы данных HSI плодов авокадо и выявлены полосы отражения в видимой и ближней инфракрасной областях спектра, взаимосвязанные с процессом созревания и содержанием влажности плодов авокадо. Установлено, что при использовании факторных нагрузок в качестве псевдоцвета возможна визуализация при поточной сортировке плодов авокадо по влажности. Построение калибровочных моделей определения влажности и сухого вещества плодов авокадо проведено на основе данных измерений влаж ности и гиперспектральных изображений. Формирование матрицы спектральных данных осуществляли двумя способами: посредством отбора спектральных сигнатур HSI случайным образом со всей поверхности плодов или поверхность изображения HSI плодов (исходные HSI) как области интереса (ROI). На основе данных измерений влажности и отбора спектральных сигнатур гиперспектральных изображений проведено построение калибровочных моделей определения влажности и сухого вещества плодов авокадо. При последовательном моделировании методом PLS (проекция на латентные структуры) разработаны точные калибровочные модели для определения влажности (RP2 = 0,89) и сухого вещества (RP2 = 0,92) в составе плодов авокадо. При построении калибровочных моделей по исходным HSI получены модели для прогнозирования влажности (RС2 = 0,99) и сухого вещества (RС2 = 0,99) в составе плодов авокадо. Предлагается использование калибровочных моделей по исходным HSI для определения влажности и сухого вещества в интервалах допустимых значений в соответствии с действующим стандартом UNECE STANDARD FFV-42:2019
Selection of initial approximation for reconstruction of images in impedance tomography
A new method was suggested for the selection of initial approximation to two fields of potentials at the reconstruction of images in impedance tomography