Comprehensive Summary Aerobic oxidation has been catching more and more attention because of its atom economy and environmental friendliness.Oxidation of diols is a challenge due to various oxidative products.Thus,hig...Comprehensive Summary Aerobic oxidation has been catching more and more attention because of its atom economy and environmental friendliness.Oxidation of diols is a challenge due to various oxidative products.Thus,highly selective aerobic oxidation affording specific products is of current interest.In this work,a combination of Fe(NO_(3))_(3)·9H_(2)O/TEMPO/KCl catalysis has been identified as an efficient recipe for the aerobic oxidation of 1,4-diols affordingγ-butyrolactones under mild conditions.The reaction exhibits decent chemo-and regioselectivity of symmetrical and unsymmetrical 1,4-diols.The optically activeγ-lactones may also be prepared from optically active 1,4-diols without erosion of the ee via this method.Furthermore,this approach was successfully applied to synthesize NBP,a commercial drug.展开更多
Bacterial quorum sensing（QS） molecules are involved in the coordination of certain behaviors such as biofilm formation, virulence and antibiotic resistance. QS molecules（autoinducers） and their corresponding recep...Bacterial quorum sensing（QS） molecules are involved in the coordination of certain behaviors such as biofilm formation, virulence and antibiotic resistance. QS molecules（autoinducers） and their corresponding receptors have been recognized as important therapeutic targets for drug-resistant infections and biofilm-associated infections（BAI）. This study assessed the multiple biological effects of homogentisic acid y-lactone（HgAL）, a furanone derivative. The anti-QS and anti-biofilm effects of HgAL against PAO1 strain were evaluated using CLSM, SEM, HPLC and other biochemical methods The results showed that HgAL could effectively inhibit the production of pyocyanin and extracellular matrix, as well as reduce the adherence ability and biofilm formation of Pseudomonas aeruginosa. Inhibition of virulence is attributed to the suppressive effect of HgAL on biosynthesis of 3-oxo-C12-HSLand C4-HSL（two kinds of QS signaling molecules in P. aeruginosa）. Our results support HgAL as a potential agent for prevention of BAI in the healthcare settings.展开更多
An unusual formal oxy transposition of vinylogous β-silyloxy-cyclobutanone 1（a 1,5-difunctionalized substrate） under mild acidic conditions（aqueous HF in CH3CN at 0℃） to the decalinic y-lactone 2 was described.A...An unusual formal oxy transposition of vinylogous β-silyloxy-cyclobutanone 1（a 1,5-difunctionalized substrate） under mild acidic conditions（aqueous HF in CH3CN at 0℃） to the decalinic y-lactone 2 was described.A plausible mechanistic pathway involving the Grob-type fragmentation and intramolecularγ-Iactonization was proposed.展开更多
Primary, secondary, and tertiary alcohols and polyols were esterified with carboxylic acidin the presence of HY zeolite. Yield of ester of primary alcohol is over 80 per cent, andthat of sec- and tert-alcohols, 40-50 ...Primary, secondary, and tertiary alcohols and polyols were esterified with carboxylic acidin the presence of HY zeolite. Yield of ester of primary alcohol is over 80 per cent, andthat of sec- and tert-alcohols, 40-50 per cent generally.γ-Lactone was synthesized byrearrangement of α- or β-octylenic to tridecylenic acid with HY zeolite.展开更多
The syntheses of 2-[(4-Fluorophenoxy)methylene]-4-(3,4,5-trimethoxyphenyl)-4-butanolide 8and 2-[(4-Fluorophenoxy)methyl]-4-(3,4,5-trimethoxyphenyl)-2-buten-γ-lactone 9 from 3-(4-Fluoro-phenoxy)propyne 1 tbrough 5 ste...The syntheses of 2-[(4-Fluorophenoxy)methylene]-4-(3,4,5-trimethoxyphenyl)-4-butanolide 8and 2-[(4-Fluorophenoxy)methyl]-4-(3,4,5-trimethoxyphenyl)-2-buten-γ-lactone 9 from 3-(4-Fluoro-phenoxy)propyne 1 tbrough 5 steps have been described.The one pot deconjugation and hydroiodination of 3with a reagent system of TMSCL/NaI/H 2O in CH 3CN was key step.展开更多
基金Financial support from the National Natural Science Foundation of China(21988101)is greatly appreciated.
文摘Comprehensive Summary Aerobic oxidation has been catching more and more attention because of its atom economy and environmental friendliness.Oxidation of diols is a challenge due to various oxidative products.Thus,highly selective aerobic oxidation affording specific products is of current interest.In this work,a combination of Fe(NO_(3))_(3)·9H_(2)O/TEMPO/KCl catalysis has been identified as an efficient recipe for the aerobic oxidation of 1,4-diols affordingγ-butyrolactones under mild conditions.The reaction exhibits decent chemo-and regioselectivity of symmetrical and unsymmetrical 1,4-diols.The optically activeγ-lactones may also be prepared from optically active 1,4-diols without erosion of the ee via this method.Furthermore,this approach was successfully applied to synthesize NBP,a commercial drug.
基金supported by the National Natural Science Foundation of China (Nos. 81401512, 41606186)the Scientific Research Fund of Hunan Provincial Education Department (No. 14B157)+1 种基金China Postdoctoral Science Foundation (No. 2016M602419)the Hong Kong Scholars Program (No. XJ2015022)
文摘Bacterial quorum sensing（QS） molecules are involved in the coordination of certain behaviors such as biofilm formation, virulence and antibiotic resistance. QS molecules（autoinducers） and their corresponding receptors have been recognized as important therapeutic targets for drug-resistant infections and biofilm-associated infections（BAI）. This study assessed the multiple biological effects of homogentisic acid y-lactone（HgAL）, a furanone derivative. The anti-QS and anti-biofilm effects of HgAL against PAO1 strain were evaluated using CLSM, SEM, HPLC and other biochemical methods The results showed that HgAL could effectively inhibit the production of pyocyanin and extracellular matrix, as well as reduce the adherence ability and biofilm formation of Pseudomonas aeruginosa. Inhibition of virulence is attributed to the suppressive effect of HgAL on biosynthesis of 3-oxo-C12-HSLand C4-HSL（two kinds of QS signaling molecules in P. aeruginosa）. Our results support HgAL as a potential agent for prevention of BAI in the healthcare settings.
基金financial support from National Natural Science Foundation of China(NSFC,Nos.21302177,21672049 and 21672030)
文摘An unusual formal oxy transposition of vinylogous β-silyloxy-cyclobutanone 1（a 1,5-difunctionalized substrate） under mild acidic conditions（aqueous HF in CH3CN at 0℃） to the decalinic y-lactone 2 was described.A plausible mechanistic pathway involving the Grob-type fragmentation and intramolecularγ-Iactonization was proposed.
文摘Primary, secondary, and tertiary alcohols and polyols were esterified with carboxylic acidin the presence of HY zeolite. Yield of ester of primary alcohol is over 80 per cent, andthat of sec- and tert-alcohols, 40-50 per cent generally.γ-Lactone was synthesized byrearrangement of α- or β-octylenic to tridecylenic acid with HY zeolite.
文摘The syntheses of 2-[(4-Fluorophenoxy)methylene]-4-(3,4,5-trimethoxyphenyl)-4-butanolide 8and 2-[(4-Fluorophenoxy)methyl]-4-(3,4,5-trimethoxyphenyl)-2-buten-γ-lactone 9 from 3-(4-Fluoro-phenoxy)propyne 1 tbrough 5 steps have been described.The one pot deconjugation and hydroiodination of 3with a reagent system of TMSCL/NaI/H 2O in CH 3CN was key step.
