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1H NMR
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Bài viết trình bày việc sử dụng phương pháp phổ cộng hưởng từ hạt nhân 1H-NMR, 13C-NMR và HSQC với các điều kiện nhiệt độ thay đổi để xác định cấu trúc của các hợp chất có hệ liên hợp đặc biệt và đặc trưng cấu trúc phân tử dẫn đến việc mất các tín hiệu phổ trong điều kiện thường.
9p
viambani
18-06-2024
2
1
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Ten new chromone derivatives were synthesized from the original 2-4-6- trihydroxyacetophenone using microwave irradiation. The product's structures were confirmed by FT-IR, 1H-NMR, and 13C-NMR spectra data. The anti-microbial activities of the obtained compounds were tested by the disc diffusion method. The results showed that most chromones have significant biological activities against Candida albicans.
10p
viambani
18-06-2024
1
0
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In this research paper we report the detailed synthesis, spectral (1H-NMR, FT-IR, and UV-Vis), crystal structure determination, DFT studies, and molecular modeling of 4-amino-3-mercapto-5-methyl-1,2,4-triazole (L2) Schiff base ligand and its complexes of cadmium as suitable bioactive agents for the treatment of malaria. From the spectroscopic results, the synthesized Schiff base has potentialtridentate coordination with themetal ion via hydroxy naphthalinic-O, azomethine-N and sulphur atom of the thione group.
17p
dianmotminh02
03-05-2024
2
1
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The ligand picolinoyl(4-ethylthiosemicarbazide) HL was synthesized by the reaction of picolinohydrazide and ethyl isothiocyanate in absolute ethanol. The structure of HL was characterized by spectroscopic methods such as IR, 1H, and 13C NMR spectroscopy.
6p
viberkshire
09-08-2023
8
5
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Bài viết trình bày chiết xuất, phân lập một số hợp chất từ cây Thài lài trắng (Commelina diffusa Burm.f.). Đối tượng và phương pháp: Cây Thài lài trắng được ngâm chiết bằng MeOH, sau đó cắn MeOH được lắc phân đoạn với n-hexan và ethyl acetat. Sử dụng các phương pháp sắc ký thích hợp để phân lập ba hợp chất sạch, ký hiệu 1-3. Sau đó, đo nhiệt độ nóng chảy, phổ khối (MS), phổ cộng hưởng từ hạt nhân (1H-NMR, 13C-NMR, DEPT) để xác định cấu trúc hóa học của chúng.
8p
vihulk
28-07-2023
11
1
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Bài viết Ứng dụng các phương pháp phân tích thống kê đa biến để phân loại nguồn gốc mật ong ở Việt Nam dựa trên dữ liệu phổ 1H-NMR tiến hành áp dụng mô hình thống kê đã biến kết hợp các dữ liệu hoá học để bước đầu phân loại nguồn gốc mật ong ở Việt Nam.
6p
viargus
03-03-2023
9
2
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As a potent antibacterial, antifungal or antiviral material, synthesis of quaternarized epoxidized soybean oil was demonstrated in this work. The first step of the synthesis is the reaction of epoxidized soybean oil (ESO) with 2-chloroethyl maleic acid (Cl-MA-ESO). The last step is quaternarization of this condensate with triethylamine (Q-MA-ESO). All the synthesized monomers were characterized by FTIR and 1H NMR techniques.
8p
lyhuyenthu
31-01-2023
8
2
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New pectin derivative (Pec-MA) was obtained in specific reaction conditions. The presence of maleoyl groups in Pec-MA structure was confirmed by 1H NMR and FTIR spectroscopy. The substitution degree of Pec-MA (DS = 24%) was determined by 1H NMR.
7p
vihermione
06-01-2023
9
3
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Different starch derivatives were evaluated as supports for attachment and recovery of macrophages (RAW 264.7 line). Gelatinized starch (G-St), acetate starch (Ac-St), carboxymethyl starch and aminoethyl starch were synthesized and characterized by FTIR, 1H NMR, SEM and static water contact angle.
10p
vihermione
06-01-2023
10
2
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The interactions and dynamic behavior of a select set of polar probe solutes have been investigated on three hydrophilic and polar commercial stationary phases using saturation transfer difference 1H nuclear magnetic resonance (STD-NMR) spectroscopy under magic angle spinning conditions.
13p
viginny
23-12-2022
7
3
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The formation of heterocyclic aromatic 1,2,3-triazole ring is approved by the appearance of singlet peak at 7.71 ppm in 1H NMR corresponding with triazolyl proton. In addition, antibacterial and antifungal activities of products are also tested with three Gram-positive bacteria (B. subtilis, S. aureus and L. fermentum), three Gram-negative bacteria (P. aeruginosa, E.coli, S. enterica), and Candida albicans fungus.
5p
visherylsandber
04-07-2022
8
2
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Trong đề tài nghiên cứu "Nghiên cứu tổng hợp một số dẫn xuất thế của thieno[3,2-b]thiophen bằng phản ứng sử dụng xöc tác palađi", nhóm tác giả đã tổng hợp được 8 dẫn xuất thế của thieno[3,2- b]thiophen bằng các phản ứng Suzuki, Heck và Sonogashira. Cấu trúc của 8 hợp chất này đã được xác định bằng các phương pháp phổ IR, 1H NMR và 13C NMR và nhiễu xạ đơn tinh thể (XRD).
11p
runordie2
07-06-2022
13
2
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The aim of the present study was to synthesize and characterize benzothiazine derivatives prepared by using 2-aminothiophenol and saccharine and in vitro screen their enzyme inhibition and antioxidant potential. Nine different derivatives were prepared and their structures were confirmed by spectral studies (EIMS, 1H and 13 C NMR). Enzyme inhibition potential of the synthesized compounds was evaluated by Ellman’s method, while antioxidant activity was determined by DPPH and FRAP assays.
9p
langthannam
29-12-2021
12
0
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Synthesis and in vitro antimicrobial activities are reported for a series of 1,3,5-substituted 4-oxo-3,4-dihydro5H -pyridazino[4,5- b]indole derivatives. Corresponding pyridazino[4,5- b]indoles were prepared from ethyl 3-formyl-1H - indole-2-carboxylate precursors and the functional group in question was installed with hydrazine and its derivatives. The purity and primary structures of pyridazino[4,5- b]indole were confirmed by IR, 1H NMR, and 13 C NMR spectroscopy and elemental analyses.
21p
langthannam
29-12-2021
5
0
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An efficient 2-component synthesis of a series of 3-(2-(substituted phenylamino)thiazol-4-yl)-2H -chromen-2- ones (3a–j) was achieved by the reaction of 3-(2-thiocyanatoacetyl)-2H -chromen-2-one (1) with a variety of suitably substituted anilines in 1:1 molar ratio in ethanol. The structures of the products were established by elemental analyses, and UV-vis, FTIR, 1H and 13C NMR, and mass spectroscopy. 3-(2-(4-Methylphenylamino)thiazol-4-yl)-2 H -chromen-2- one (3j) was further characterized by single crystal X-ray diffraction study.
11p
langthannam
29-12-2021
10
0
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A series of binucleating Cu(II), Ni(II), and Zn(II) complexes of bicompartmental ligands with ONO donors were prepared. The ligands were synthesized by the condensation of 5-substituted-3-phenyl-1H -indole-2-carboxyhydrazides and 4,6-diacetylresorcinol. The newly synthesized ligands and their complexes were characterized by elemental analysis and various spectral studies like IR, 1H NMR, ESI-mass, UV-Vis, ESR, thermal studies, magnetic susceptibility, molar conductance, and powder-XRD data.
21p
langthannam
29-12-2021
8
0
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The essential oils of Actinolema macrolema Boiss. (Apiaceae) were obtained by hydrodistillation in the first 3 (sample A) and the following 3 h (sample B) from crushed fruits and dried leaves (sample C), which were subsequently analyzed by GC and GC-MS. Overall, 64 components were characterized, representing 93% of the leaf oil. Thirty components were characterized from the fruit oil representing 95% of the first fraction and 90% of the second fraction consecutively.
10p
langthannam
29-12-2021
11
0
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A series of potential biological active acyl hydrazone derivatives containing ibuprofen moiety (compounds 4a–4p) was synthesized by the condensation of ibuprofen hydrazone with aromatic aldehydes using conventional and microwave irradiation methods. The microwave method was found to be successful with nearly the same or higher yields and shorter reaction time, and it was more environmentally friendly compared to the conventional heating method. The chemical structures of the synthesized compounds were characterized by IR, 1H NMR, and APT-NMR spectroscopy.
9p
langthannam
29-12-2021
9
0
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The new heterobimetallic [Mg(II)-Ti(IV)]-µ-oxoisopropoxide was synthesized on treatment of magnesium acetate with titanium(IV) isopropoxide in refluxing decalin in 1:2 molar ratio and characterized by liberated isopropanol, elemental, spectral (IR, 1H and 13C NMR, and mass), thermal analysis, and molecular weight data.
9p
langthannam
29-12-2021
7
0
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New phthalocyanine compounds containing mixed-donor substituted macrocyclic groups were synthesized. The complexes of metal phthalocyanines 3–5 were prepared by the reaction of 2 to get dinitrile derivative complexes by means of the corresponding anhydrous metal salts. Structures of the new compounds were characterized by IR, 1H NMR, 13C NMR, elemental analysis, and MS spectral data.
11p
langthannam
29-12-2021
8
0
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