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91.
De Muynck H Madder A Farcy N De Clercq PJ Pérez-Payán MN Öhberg LM Davis AP 《Angewandte Chemie (International ed. in English)》2000,39(1):145-148
Recursive deconvolution of a 729-membered peptide library has identified three active sequences, in which both Ser and His are present in one of the two tripeptidic chains generated on a steroidal scaffold (see structural formula), for the cleavage of an activated p-nitrophenyl ester. This combinatorial approach aims at searching for serine-protease-like activity. 相似文献
92.
The apparent and limiting apparent molal volumes of dilute aqueous solutions of K3[Al(ox)3] · 3H2O, K3[Fe(ox)3] · 3H2O, K3[Co(ox)3] · 3H2O, and K3[Cr(ox)3] · 3H2O complexes were determined from density data measured at 15°, 25°, and 35°C. The apparent and limiting apparent molal adiabatic
compressibilities of these complexes were determined from measured ultrasonic sound velocities at 15°, 25°, and 35° in dilute
aqueous solutions. The volume change associated with complex formation is discussed in terms of the nature of the coordinate
bond and the overall hydration behavior of these complexes. 相似文献
93.
Deep Jyoti Bhuyan Quan V. Vuong Anita C. Chalmers Ian A. van Altena Michael C. Bowyer Christopher J. Scarlett 《Chemical Papers》2016,70(5):567-575
Eucalyptus species have found their place in traditional medicine and pharmacological research and they have also been shown to possess a large number of phenolic compounds and antioxidants. The present study sought to implement conventional extraction to yield maximal total phenolic content (TPC), total flavonoid content (TFC), proanthocyanidins, antioxidants, and saponins from E. robusta using different solvents. The most suitable extraction solvent was further employed for extracting phytochemicals from E. saligna, E. microcorys, and E. globulus to select the Eucalyptus species with the greatest bioactive compound content. The results emphasised the efficiency of water in extracting TPC ((150.60 ± 2.47) mg of gallic acid equivalents per g), TFC ((38.83 ± 0.23) mg of rutin equivalents per g), proanthocyanidins ((5.14 ± 0.77) mg of catechin equivalents per g), and antioxidants ABTS ((525.67 ± 1.99) mg of trolox equivalents (TE) per g), DPPH ((378.61 ± 4.72) mg of TE per g); CUPRAC ((607.43 ± 6.69) mg of TE per g) from E. robusta. Moreover, the aqueous extract of E. robusta had the highest TPC, TFC and antioxidant values among the other Eucalyptus species tested. These findings highlighted the efficiency of conventional extraction in extracting natural bioactive compounds from Eucalyptus species for pharmaceutical and nutraceutical applications. 相似文献
94.
Gunter S Wolf RC Leuterer F Gruber O Kaufmann M Lackner K Maraschek M Mc Carthy PJ Meister H Peeters A Pereverzev G Salzmann H Schade S Schweinzer J Suttrop W 《Physical review letters》2000,84(14):3097-3100
Internal transport barriers have been demonstrated to exist also under conditions with T(e) approximately T(i) approximately 10 keV and predominant electron heating of the tokamak core region. Central electron cyclotron heating was added to neutral beam injection-heated ASDEX Upgrade discharges with a preexisting internal transport barrier, established through programmed current ramping leading to shear reversal. Compared to a reference internal transport barrier discharge without electron cyclotron resonance heating, the electron heat conductivity in the barrier region was found not to increase, in spite of a fivefold increase in electron heat flux, and also angular momentum and ion energy transport did not deteriorate. 相似文献
95.
Samuzal Bhuyan Dharmendra Das Dr. Amit Chakraborty Susanta Mandal Dr. Kumaraswamy Dhanabal Dr. Biswajit Gopal Roy 《化学:亚洲杂志》2021,16(24):4108-4121
Chiral polyheterocycles are one of the most frequently encountered scaffolds in natural products and in current drugs repertoire. A carbohydrate-based diversity oriented synthetic (DOS) approach has been employed for gaining access to many structurally diverse and stereochemically complex rigid polyheterocyclic molecules with multiple chiral hydroxyl groups to enhance aqueous solubility. Inexpensive chiral pool of D-Glucose has been judiciously exploited to get access of complex chiral polyheterocyclic structures using inexpensive, common achiral reagents and domino-Knoevenagel hetero-Diels-Alder (DKHDA) reaction as one of the key synthetic tools. Stereochemistry of newly generated stereocenters of polycyclic structures are unambiguously determined through NMR and X-ray crystallographic study. A chemoinformatic comparison (PCA and PMI) with 40 branded blockbuster drugs showed that newly generated polyheterocycles have good three-dimensional scaffold diversity and most of these pass the Lipinski filter of drug-likeness. 相似文献
96.
Avijit Pramanik Mouchumi Bhuyan Rajib Choudhury Gopal Das 《Journal of Molecular Structure》2008,879(1-3):88-95
The simple tripodal amine ligand Tris-[2-(naphthalen-1-yloxy)-ethyl]-amine (L1) was screened for anion recognition. Four crystal structures confirmed the inorganic as well as organic anion recognition in the solid state. Solid-state structures are results of supramolecular self-assembly and 3D molecular network involves C–HO and C–Hπ bonding in the crystal lattice. In the solid state, it forms a strong C–HCl and C–HO type interactions with the anions. This anion recognition was also confirmed by steady state fluorescence spectroscopy. In complex 4, L1 is confined between 2D hydrogen bonded sheet formed by pyromellitic acid anion. L1 shows unusually high selectivity toward nitrate in solution resulting in both a dramatic color change and a concomitant quenching of luminescence. 相似文献
97.
This paper will review the dramatic increase in our knowledge of one and two proton unbound nuclei [1] such as recoil decay
tagging [2] are revealing unique insights into the structure of nuclei beyond the proton drip-line. These studies of excited
states provide complementary information to proton radioactivity studies, particularly regarding the role of deformation [3].
Radioactive beams are being used to study two-proton unbound resonances and to study explosive nuclear astrophysical reactions
in the region of the proton drip-line. 相似文献
98.
Hazarika Jnyandeep Ganguly Mausumi Borgohain Gargi Baruah Indrani Sarma Shruti Bhuyan Pranjal Mahanta Rita 《Structural chemistry》2020,31(5):2011-2021
Structural Chemistry - Chlorpyrifos is an extensively used organophosphate pesticide showing broad-spectrum effectiveness on various target pests. Long-term sublethal exposure to this pesticide is... 相似文献
99.
100.
An efficient method was developed for the synthesis of fused dihydroindeno[1,2-b]furans. One-pot three-component reaction of 1,3-indanedione, aromatic aldehyde and pyridinium ylide in the presence of triethylamine under microwave-irradiation in solvent-free conditions afforded dihydroindeno[1,2-b]furans in a diastereoselective manner in excellent yields. 相似文献