Because global warming has been a constant issue in the environmental field, many studies on the mitigation of CO2 have been conducted. This study for carbon dioxide utilization dealt with the characteristics of magnesium carbonate formation using Mg2+ ions separated from seawater-based industri...
Xiebai is an edible Chinese herb with various health and therapeutic benefits. To evaluate its nutritional and health values, the free amino acids and derivatives of its two botanical origins (i.e., Allium chinense G. Don and Allium macrostemon Bunge) were isolated using a solvent extraction met...
Publisher SummaryThis chapter analyzes the compounds with seven-membered and larger rings containing one or more atoms of unusual hetero elements together with nitrogen or elements of group VI. 8-Mercura-1,4-dioxadibenzo[f,i]cycloundeca-6,9-diene is an example of mercury compounds. Aluminum and ...
A catalytic amount of trimethylsilyl triflate (TMSOTf) remarkably facilitates the selective conjugate addition of a variety of silyl phosphites, prepared in situ from dialkyl phosphites and N,O-bis(trimethylsilyl)acetamide, to cyclic enones giving 1,4-adducts in high yields.
A direct and practical method for the construction of β-mannosidic linkages is described. While β-selectivities in the TMSOTf-promoted glycosidation of 2,3,4,6-tetra-O-benzyl-d-mannosyl diethyl phosphite are found to be highly dependent on the reactivity of acceptor alcohols, 2,3-di-O-benzyl-4...
An efficient method was developed for the synthesis of a variety of arylphosphorus compounds from P–H compounds using o-(trimethylsilyl)aryl triflates as aryne precursors. The reaction provides a practical preparation of various arylphosphorus compounds via aryne intermediates utilizing diarylp...
An efficient and enantioselective phospha-Michael addition of diethyl phosphite to chalcones has been established. In the presence of a catalytic amount of chiral lanthanide silylamide generated from [(Me3Si)2N]3Yb(μ-Cl)Li(THF)3 and salen, the reaction produced the target γ-oxophosphonates wit...
Reaction of 2-formylbenzoates with hexamethyldisilazane and diethyl phosphite in the presence of Yb(OTf)3 proceeded smoothly at room temperature to afford addition adducts, which were readily cyclized to 3-phosphonate phthalides by adding trifluoroacetic acid (TFA). The reactions employing Sc(OT...
A PdP(t-Bu)3 catalyst system has revealed very high activity and selectivity for the amination of N-(hetero)aryl halides with unprotected piperazine. A wide variety of N-(hetero)arylpiperazines could be prepared using this catalyst. Turnover numbers up to 6400mol/mol have been obtained.
Reactions of [Pt2(μ-Cl)2(C∩P)2] (C∩P = CH2C(Me2)PBut2-C,P) with various anionic ligands differing in ligand bite and denticity have been investigated and the resulting products have been characterized by elemental analyses and NMR (1H, 13C, 31P, 195Pt) spectroscopy. Stereochemistry of the com...
Two new gold(I) complexes that contain tri-ter-butylphosphine and dialkyl dithiocarbamate ligands were synthesized and characterized by FTIR, NMR spectroscopy, Cyclic voltammetry, elemental analysis and X-ray diffraction. The in vitro cytotoxicity of both complexes was examined against A549 (lun...
Neurosteroids have been reported to modulate memory processes in rodents. Three analogues of dehydroepiandrosterone (DHEA), two of them previously described (7β-aminoDHEA and 7β-amino-17-ethylenedioxy-DHEA), and a new one (3β-hydroxy-5α-androstane-6,17-dione) were synthesized, and their effe...
3β-Hydroxy-5β-cholestan-6-one was identified in the EtOAc extract of Ajuga hairy roots by micro-analysis using LC–MS/MS in the multiple reaction mode (MRM). Furthermore, administration of (2,2,4,4,7,7-2H6)- and (2,2,4,4,6,7,7-2H7)-cholesterols to the hairy roots followed by LC–MS/MS analysis...
Anthraquinone (AQ) derivatives are the largest group of natural quinones. Other natural quinones are naphthoquinones and benzoquinones. AQs also constitute the largest group of natural pigments with about 700 compounds described. AQ 1 as a building block of many dyes is attractive because of its...
Chemo-enzymatic synthesis afforded a series of CMP-activated sialic acids carrying a photoreactive group at C-9 or C-5, and in part a radiolabel as well. They were found to be accepted by α2,6-sialyltransferase. - Differing amino group reactivity of novel 5,9-diamino sialic acid enabled us to a...
The purpose of this review is to present methods of chromatographic analysis of aromatic carboxylic acids. The separation, identification and quantitative analysis of aromatic carboxylic acids are necessary because of their importance as non-steroid antiphlogistic drugs, semi-products of biosynt...
We describe a new one-pot synthesis of 2,3-diaryl-5H-imidazo[2,1-a]isoindol-5-ones via the reaction of 1,2-diketones, 2-formylbenzoic acids, and ammonium acetate in acetic acid under reflux conditions and in the absence of a catalyst.
In this study, different detoxification treatments (XAD-4 resin adsorption [XAD] and electrodialysis) on oxalic acid pretreated hydrolysate were evaluated. Two different detoxification processes were applied to remove fermentation inhibitors from the oxalic acid pretreated hydrolysate of eucalyp...
This chapter is a comprehensive review of new methods introduced since 1995 for preparations of acid fluorides, chlorides, bromides, and iodides. These are compared to older more traditional procedures. New fluoride salts containing a nucleophilic fluoride ion have been introduced. Acid chloride...
1H NMR (with particular reference to the acidic protons) and 13C NMR examination of the reaction products from phthalic anhydride and dialkylcadmiums, formally represented as 2-acylbenzoic acids (open chain structure), show that they are 3-hydroxy-3-alkylphthalides (the ring structure) in the so...
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