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91.
An efficient and concise total synthesis of naturally occurring pyranochalcones was achieved from readily available 2,4-dihydroxyacetophenone and 2,4-dihydroxy-6-methoxyacetophenone. The key steps in the synthetic strategy were ethylenediamine diacetate-catalyzed benzopyran formation and aldol reactions. 相似文献
92.
In the Water, Energy and Waste Directive, the European Commission provides for the use of household washing programmes with lower temperatures (30–40 °C) and lower water consumption. However, low washing temperatures and the absence of oxidising agents in the liquid detergents, and their reduced content in powder detergents, allow biofilm formation in washing machines and the development of an unpleasant odour, while the washed laundry can become a carrier of pathogenic bacteria, posing a risk to human health. The aim of the study was to determine whether the addition of hydrogen peroxide (HP) to liquid detergents in low-temperature household washing allows disinfection of the laundry without affecting the properties of the washed textiles even after several consecutive washes. Fabrics of different colours and of different raw material compositions were repeatedly washed in a household washing machine using a liquid detergent with the addition of 3% stabilised HP solution in the main wash, prewash or rinse. The results of the antimicrobial activity, soil removal activity, colour change and tensile strength confirmed the excellent disinfection activity of the 3% HP, but only if added in the main wash. Its presence did not discolour nor affect the tensile strength of the laundry, thus maintaining its overall appearance. 相似文献
93.
This paper describes simple and efficient approaches for the preparation of β-enaminoamides through thermal Wolff rearrangement of cyclic diazodicarbonyls followed by trapping with various amines. The synthesized β-enaminoamides were readily converted into uracil derivatives. 相似文献
94.
95.
Yong Rok Lee 《合成通讯》2013,43(5):865-869
An efficient synthesis of dihydrofurans is achieved by rhodium-catalyzed dipolar cycloaddition of cyclic diazodicarbonyl compounds with α,β-unsaturated esters. 相似文献
96.
Sharma Kavita Baral Ek Raj Akhtar Muhammad Saeed Lee Yong Rok Kim Sung Hong Wee Young-Jung 《Research on Chemical Intermediates》2017,43(4):2387-2399
Research on Chemical Intermediates - Indole derivatives have attracted significant attention in organic synthesis and bioactivity research owing to their substantial biological activity. In the... 相似文献
97.
One‐step synthesis of biologically active (±)‐confluentin is described from commercially available orcinol with trans,trans‐farnesal in the presence of ethylenediamine diacetate as a catalyst. Further conversion of synthetic confluentin to highly potent anti‐HIV agent, (±)‐daurichromenic acid, is accomplished by formylation and oxidation in two steps. 相似文献
98.
An efficient synthesis of spinochalcone B and its analogues is achieved from readily available 2H‐pyran. 相似文献
99.
Srinivasa Rao KollaYong Rok Lee 《Tetrahedron》2011,67(43):8271-8275
A variety of novel 2-amino-5-hydroxy-4H-chromene derivatives with various substituents on the 4H-chromene ring were efficiently synthesized by one-pot reactions of substituted resorcinols and various 2-benzylidenemalononitriles in the presence of calcium hydroxide in methanol at room temperature. This simple method provided 2-amino-5-hydroxy-4H-chromenes with high yields under mild reaction conditions. 相似文献
100.
Auberger N Frlan R Al-Dabbagh B Bouhss A Crouvoisier M Gravier-Pelletier C Le Merrer Y 《Organic & biomolecular chemistry》2011,9(24):8301-8312
Stable analogs of bacterial transferase MraY substrate or product with a pyrophosphate surrogate in their structure are described. β-ketophosphonates were designed as pyrophosphate bioisosteres and were investigated as UDP-GlcNAc mimics. The developed strategy allows introduction of structural diversity at a late stage of the synthesis. The biological activity of the synthesized compounds was evaluated on the MraY enzyme. 相似文献