First Total Synthesis of Isopsoralenoside

The first total synthesis of the natural product iopsoralenoside, isolated from the n-butyl alcohol extract of Fructus Psoraleae (FP), was achieved in 17% yield over 7 steps. The key steps of the process are the glycosylation and irradiation promoted by ultraviolet light. This synthesis provides a sufficient amount of synthesized trans- and cis-isopsoralenoside for further bioassays.

Nghiên cứu điều kiện tiền xử lý và chiết tách collagen từ da cá lóc (Channa striata) bằng pepsin

Nghiên cứu điều kiện tiền xử lý và chiết tách collagen từ da cá lóc bằng pepsin đã được thực hiện. Kết quả cho thấy da cá lóc được xử lý với 10% butyl alcohol trong 72 giờ thì hàm lượng lipid còn lại thấp nhất là 15,3%. Collagen từ da cá lóc được chiết tách với 0,45% pepsin trong 24 giờ cho hiệu suất thu hồi 13,7% và độ hòa tan cực đại ở pH 1 - 4 và nồng độ NaCl từ 0,2 - 0,6 M. Bên cạnh đó, phổ FTIR cho thấy mối quan hệ chặt chẽ giữa số bước sóng trong vùng amide I và vùng amide III đặc biệt là sự ổn định của cấu trúc xoắn ba, cho thấy collagen từ da cá lóc có đầy đủ nhóm chức năng của collagen loại I. Collagen có màu sáng với giá trị L* là 62,4 và hàm lượng imino acid là 204 (đơn vị/1000 đơn vị). Kết quả nghiên cứu cho thấy có thể sử dụng pepsin để thay thế hoá chất nhằm giảm thiểu lượng hoá chất thải ra môi trường, tận dụng da cá lóc như nguồn nguyên liệu để sản xuất collagen.

SYNTHESIS OF 2-NITRO-1,3-BIS(3,3’-DIHYDROXYMETHYL)-1,2,3-TRIAZOLYL-2-AZAPROPANE BY THE REACTION OF AZIDE-ALKYN CYCLOADDITION

2-Нитро-1,3-бис(3,3'-дигидроксиметил)-1,2,3-триазолил-2-азапропан (2-НДТАП) представляет интерес в качестве исходного вещества в синтезе высокоэнергетических соединений. В статье рассмотрен синтез 2-НДТАП реакцией азид-алкинового циклоприсоединения 1,3-диазидо-2-нитро-2-азапропана с пропаргиловым спиртом в среде трет-бутилового спирта в присутствии медного катализатора (проволока, порошок меди, оксид меди, нанооксид меди). Исследовано влияние катализатора и температуры процесса на его продолжительность, выход и качество продукта. Структура 2-НДТАП подтверждена методами ИК- и ЯМР-спектроскопии. В результате разработан метод получения 2-НДТАП с выходом 62 % и содержанием основного вещества выше 97 %. 2-Nitro-1,3-bis (3,3'-dihydroxymethyl)-1,2,3-triazolyl-2-azapropane (2-NDTAP) is of interest as a starting material in the synthesis of high-energy compounds. The article discusses the synthesis of 2-NDTAP the reaction of azide-alkyne cycloaddition 1,3-diazido-2-nitro-2-azapropane with propargyl alcohol in tert-butyl alcohol in the presence of a copper catalyst (wire, copper powder, copper oxide, nano copper oxide). The influence of the catalyst and the temperature of the process on its duration, yield and product quality has been investigated. The structure of 2-NDTAP was confirmed by IR and NMR spectroscopy. As a result, a method for obtaining 2-NDTAP with a yield of 62 % and a basic substance content of more than 97 % was developed.

Evaluation of Antioxidant and Antifungal Activity of the Whole Part of Dactyloctenium aegyptium Weed on Bengal Gram

Background: This study was conducted about the effectiveness of weed Dactyloctenium aegyptium. Weedsare familiar dominant, redundant, adverse and weed that contend with sophisticated crop for water, nutrient and sunlight and another several reasons such as, high growth rate, high reproductive rate and produce harmful or beneficial allelopathical effect of cultivated crops. The stems of Dactyloctenium aegyptium are willowy, geniculate and leaves are found roughly. Methods: This Investigation was done in 2018-19 to 2020-21. Different part of Dactyloctenium aegyptium as leaves and seed was taken from the near area of Sardar Vallabh Bhai Patel Agriculture and Technology University Modipuram Meerut. The samples were shade dry for 24 to 48 hours and then grind in the powder form. The extract were prepare in different organic solvent as Methanol, Ethyl acetate, Butyl alcohol, Benzene and Water at 1:10 ratio. Antioxidant activity of weed extracts by three methods named DPPH FRAP and ABTS methods. Result: All part of this weed show effectiveness due to the presence of active compound, who responsible for the positive result. Extract mixed with media at a particular concentration i.e. 5%, 10% and 15% show effect on soil borne fungal phytopathogens and then over the surface of petriplate the growth was appear reduce when we increase the concentration of extract. At the end we conclude that the 15% extract concentration of both part of Dactyloctenium reduce the growth of all the soil borne fungal phytopathogens.

Calcium Carbonate@silica Composite with Superhydrophobic Properties

In this paper, spherical calcium carbonate particles were prepared by using CaCl2 aqueous solution + NH3·H2O + polyoxyethylene octyl phenol ether-10 (OP-10) + n-butyl alcohol + cyclohexane inverse micro emulsion system. Then, nanoscale spherical silica was deposited on the surface of micron calcium carbonate by Stöber method to form the composite material. Scanning electron microscope (SEM), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS) were used to characterize the morphology and structure of the composite material. It is found that the surface of the composite material has a micro-nano complex structure similar to the surface of a “lotus leaf”, making the composite material show hydrophobicity. The contact angle of the cubic calcium carbonate, spherical calcium carbonate and CaCO3@SiO2 composite material were measured. They were 51.6°, 73.5°, and 76.8°, respectively. After modification with stearic acid, the contact angle of cubic and spherical CaCO3 were 127.1° and 136.1°, respectively, while the contact angle of CaCO3@SiO2 composite was 151.3°. These results showed that CaCO3@SiO2 composite had good superhydrophobicity, and the influence of material roughness on its hydrophobicity was investigated using the Cassie model theory.

Removal of chromium (VI) ions from aqueous solutions

The object of the research is the flotoextraction of chromium (VI) ions from model and real waste waters. Hexavalent chromium compounds pose a serious hazard to surface and ground waters and can have mutagenic and carcinogenic effects on living organisms. The study of the process of flotoextraction as a method of purifying waste water from heavy metals using the example of chromium (VI) ions is an important task. The paper considers flotoextraction of chromium (VI) ions using a cationic surfactant – hexadecylpyridinium chloride and butyl alcohol as the organic phase. The dependences of the process efficiency on the presence of a cationic surfactant, the flotoextraction time, the type of organic extractant, the nature of the collector and the surfactant: Cr molar ratio, the initial concentration of pollutants, and the pH of the initial solution were obtained. Certain rational conditions for flotation allow removing 98–99.6 % of pollutants. The method was tested on real wastewater. The importance of this study is emphasized by the fact that flotoextraction has a number of features and advantages. In particular, the possibility of multiple concentration of pollutant ions in small volumes of an organic solvent and the possibility of its further regeneration. In this case, a much smaller amount of an organic solvent is used and the process is not limited by the distribution constant (compared to the extraction method). Flotoextraction is also characterized by the absence of foam (compared to the flotation method) and the absence of large amounts of wet sludge (compared to the reagent method). The proposed method provides a sufficient level of chromium ions removal from wastewater, and can also be used in systems for local wastewater treatment with the subsequent return of water to the technological process. This will ensure a reduction in costs for the consumption of water resources, discharge of wastewater into water bodies, and also limit the ingress of harmful substances into the environment.

Study on the Characteristic Components of Distinguishing Dalbergia cochinchinensis from the Other Three Similar Dalbergia Species

Dalbergia cochinchinensis can be distinguished from Dalbergia retusa, Dalbergia bariensis, and Dalbergia oliveri quickly using infrared spectrum characteristic peaks as shown in a previous study. To investigate the components corresponding to the infrared characteristic peaks of Dalbergia cochinchinensis, petroleum ether, ethyl acetate, and butyl alcohol were sequentially used to extract the dispersion liquid of D. cochinchinensis. The petroleum ether extracts were further fractionated by column chromatography, using Fourier-transform infrared spectroscopy (FTIR) to track the characteristic components during separation. FTIR spectra of petroleum ether extractives indicated the presence of aromatic ketones and olefin compounds. The gas chromatography–mass spectrometry research showed some main components and gave possible structure. Furthermore, their detailed structures were characterized thorough a nuclear magnetic resonance approach, and then two possible components (3,5-dihydroxy-7-methoxy-2-phenylchroman-4-one and 3,5,7-trihydroxy-2-phenylchroman-4-one) were identified.