Two representative macrocyclic lactones with methoxysulfonyl side chain(5a and 5b)were synthesized employing Michael addition with acrolein and ring enlargement as the key steps,starting from potassium,α-oxocycloai...Two representative macrocyclic lactones with methoxysulfonyl side chain(5a and 5b)were synthesized employing Michael addition with acrolein and ring enlargement as the key steps,starting from potassium,α-oxocycloaikylsulfonates(1)in total yields of 45 and 57%,respectively.展开更多
The macrocyclic lactones building on calix[4]arenes 3a-b and double calix[4]arenes 4a-b were synthesized by the reaction of p-tert-butylcalix[4]arene (1a) or calix[4]arene (1b) with glycol bis(2-chloroacetate) (2). Th...The macrocyclic lactones building on calix[4]arenes 3a-b and double calix[4]arenes 4a-b were synthesized by the reaction of p-tert-butylcalix[4]arene (1a) or calix[4]arene (1b) with glycol bis(2-chloroacetate) (2). The conditions to improve the yields of double calix[4]arenes have been discussed.展开更多
The effects of the chain length and stereo-factor of substrates and solvents on the lipase catalysed lactonization of ω-hydroxy-ester were studied, And also the catalytic effects of various enzymes were compared.
Synthesis of mcrocyclic lactones has been applied to medical and flavor field. Triglycerides(2) of ω-hydroxycarboxylic acids synthesized from malania oleifera chum oil(1) via ozonization and reduction, and compound 2...Synthesis of mcrocyclic lactones has been applied to medical and flavor field. Triglycerides(2) of ω-hydroxycarboxylic acids synthesized from malania oleifera chum oil(1) via ozonization and reduction, and compound 2 were catalytically transformed to macrocyctic lactones(3). This is a new method involving fewer steps and a 61% yield of cyclopentadecanolide was obtained. The reactive properties of macrolactonization of ω-hydroxycarboxylic acids were also studied. The result obtained shows that the priority order of macrolactonization as follows: 11-undecalactone>cyclotridecanolide>cyclopentadecanolide, i.e. the short chain ω-hydroxycarboxylic acids were preferentially cyclized.展开更多
紫胶桐酸是一种具有生物活性的长链羟基烷酸,可用于大环内酯的合成。以紫胶桐酸多羟基作为起始原料,利用高度稀释的合成策略,通过缩醛选择性保护邻二醇、直链前体内酯化环合及酸催化环缩醛脱保护三步反应制备得到了目标产物9,10-二羟基...紫胶桐酸是一种具有生物活性的长链羟基烷酸,可用于大环内酯的合成。以紫胶桐酸多羟基作为起始原料,利用高度稀释的合成策略,通过缩醛选择性保护邻二醇、直链前体内酯化环合及酸催化环缩醛脱保护三步反应制备得到了目标产物9,10-二羟基-环十六内酯,总收率为31%,所得产物经红外光谱(IR)、核磁共振氢谱和碳谱(1 H NMR和13C NMR)、电喷雾质谱(ESI-MS)表征得以证实。实验均在室温下进行,反应条件温和,简洁有效。展开更多
Three new β-resorcylic acid lactones (RALs), paecilomycins G-I (1--3), and eight known compounds, aigia- lomycins B--D (4--6), 1',2'-epoxy aigialomycin D (7), zearalenone (8), 7'-dehydrozearalenone (9)...Three new β-resorcylic acid lactones (RALs), paecilomycins G-I (1--3), and eight known compounds, aigia- lomycins B--D (4--6), 1',2'-epoxy aigialomycin D (7), zearalenone (8), 7'-dehydrozearalenone (9), and trans-7',8'-dehydrozearalenol (10), antibiotic LL-Z1640-1 (11), were isolated from the mycelial solid culture of Paecilomyces sp. SC0924. Their structures were established by spectroscopic methods and chemical means. In an assessment of antifungal activity by the well plate diffusion method, five known RALs, 4-7 and 11 showed weak activities against Peronophythora litchii.展开更多
文摘Two representative macrocyclic lactones with methoxysulfonyl side chain(5a and 5b)were synthesized employing Michael addition with acrolein and ring enlargement as the key steps,starting from potassium,α-oxocycloaikylsulfonates(1)in total yields of 45 and 57%,respectively.
文摘The macrocyclic lactones building on calix[4]arenes 3a-b and double calix[4]arenes 4a-b were synthesized by the reaction of p-tert-butylcalix[4]arene (1a) or calix[4]arene (1b) with glycol bis(2-chloroacetate) (2). The conditions to improve the yields of double calix[4]arenes have been discussed.
文摘The effects of the chain length and stereo-factor of substrates and solvents on the lipase catalysed lactonization of ω-hydroxy-ester were studied, And also the catalytic effects of various enzymes were compared.
文摘Synthesis of mcrocyclic lactones has been applied to medical and flavor field. Triglycerides(2) of ω-hydroxycarboxylic acids synthesized from malania oleifera chum oil(1) via ozonization and reduction, and compound 2 were catalytically transformed to macrocyctic lactones(3). This is a new method involving fewer steps and a 61% yield of cyclopentadecanolide was obtained. The reactive properties of macrolactonization of ω-hydroxycarboxylic acids were also studied. The result obtained shows that the priority order of macrolactonization as follows: 11-undecalactone>cyclotridecanolide>cyclopentadecanolide, i.e. the short chain ω-hydroxycarboxylic acids were preferentially cyclized.
文摘紫胶桐酸是一种具有生物活性的长链羟基烷酸,可用于大环内酯的合成。以紫胶桐酸多羟基作为起始原料,利用高度稀释的合成策略,通过缩醛选择性保护邻二醇、直链前体内酯化环合及酸催化环缩醛脱保护三步反应制备得到了目标产物9,10-二羟基-环十六内酯,总收率为31%,所得产物经红外光谱(IR)、核磁共振氢谱和碳谱(1 H NMR和13C NMR)、电喷雾质谱(ESI-MS)表征得以证实。实验均在室温下进行,反应条件温和,简洁有效。
文摘Three new β-resorcylic acid lactones (RALs), paecilomycins G-I (1--3), and eight known compounds, aigia- lomycins B--D (4--6), 1',2'-epoxy aigialomycin D (7), zearalenone (8), 7'-dehydrozearalenone (9), and trans-7',8'-dehydrozearalenol (10), antibiotic LL-Z1640-1 (11), were isolated from the mycelial solid culture of Paecilomyces sp. SC0924. Their structures were established by spectroscopic methods and chemical means. In an assessment of antifungal activity by the well plate diffusion method, five known RALs, 4-7 and 11 showed weak activities against Peronophythora litchii.