Using an available compound 3 pentanone(1) as starting material, the key intermediate compound 4,6 dimethyl 3,7 nonandione(5) was synthesized through the addition elimination of silylenol ether and Michael addition of...Using an available compound 3 pentanone(1) as starting material, the key intermediate compound 4,6 dimethyl 3,7 nonandione(5) was synthesized through the addition elimination of silylenol ether and Michael addition of α methylene 3 pentanone(4) with silylenol ether(2). In the presence of chiral reagent 6 β phenyl amino 3 β,5α chlorestandiol(7), compound (5) was reduced by KBH 4 directly to give Tobacco Beetle Pheromone (7S) (-) 4,6 dimethyl 7 hydroxyl 3 nonanone(6). 25 D=-35 87°( c =0 23, CHCl 3), overall yield 23 9%.展开更多
胆固醇是人体重要的脂质,胆固醇水平过高可引发高胆固醇血症等疾病,3-羟基-3-甲基戊二酰辅酶A还原酶(3-hydroxy-3-methylglutaryl coenzyme A reductase,HMGCR)是催化胆固醇生物合成中的限速酶,因此HMGCR是调节胆固醇稳态的关键因素,HM...胆固醇是人体重要的脂质,胆固醇水平过高可引发高胆固醇血症等疾病,3-羟基-3-甲基戊二酰辅酶A还原酶(3-hydroxy-3-methylglutaryl coenzyme A reductase,HMGCR)是催化胆固醇生物合成中的限速酶,因此HMGCR是调节胆固醇稳态的关键因素,HMGCR在体内的调控机制十分复杂。本文从HMGCR的转录表达、降解、活性方面总结了该酶调控机制的研究进展及与相关疾病的关系。展开更多
在催化剂过氧磷钨酸十二烷基吡啶盐(Cat-PW4)的作用下,α-蒎烯与H2O2反应生成主要产物(3R,4R)-4,7,7-三甲基-6-氧杂二环[3.2.1]辛烷-3,4-二醇。不同反应条件对反应转化率和选择性的实验结果表明,最佳反应条件为:12.8 mmolα-蒎烯、5 m ...在催化剂过氧磷钨酸十二烷基吡啶盐(Cat-PW4)的作用下,α-蒎烯与H2O2反应生成主要产物(3R,4R)-4,7,7-三甲基-6-氧杂二环[3.2.1]辛烷-3,4-二醇。不同反应条件对反应转化率和选择性的实验结果表明,最佳反应条件为:12.8 mmolα-蒎烯、5 m L溶剂三氯甲烷、0.2 g催化剂、3.3 m L 30%H2O2,反应温度40℃,反应时间3 h,α-蒎烯转化率和产物的选择性分别为94.7%和39.8%。反应结束后,该产物存在于水相和有机相中,通过萃取和重结晶分离提纯,得率11%,纯度达到98%;其分子结构通过红外光谱、紫外光谱、1H核磁共振谱、13C核磁共振谱、低分辨率质谱及高分辨率质谱确证。展开更多
文摘Using an available compound 3 pentanone(1) as starting material, the key intermediate compound 4,6 dimethyl 3,7 nonandione(5) was synthesized through the addition elimination of silylenol ether and Michael addition of α methylene 3 pentanone(4) with silylenol ether(2). In the presence of chiral reagent 6 β phenyl amino 3 β,5α chlorestandiol(7), compound (5) was reduced by KBH 4 directly to give Tobacco Beetle Pheromone (7S) (-) 4,6 dimethyl 7 hydroxyl 3 nonanone(6). 25 D=-35 87°( c =0 23, CHCl 3), overall yield 23 9%.
文摘胆固醇是人体重要的脂质,胆固醇水平过高可引发高胆固醇血症等疾病,3-羟基-3-甲基戊二酰辅酶A还原酶(3-hydroxy-3-methylglutaryl coenzyme A reductase,HMGCR)是催化胆固醇生物合成中的限速酶,因此HMGCR是调节胆固醇稳态的关键因素,HMGCR在体内的调控机制十分复杂。本文从HMGCR的转录表达、降解、活性方面总结了该酶调控机制的研究进展及与相关疾病的关系。
文摘在催化剂过氧磷钨酸十二烷基吡啶盐(Cat-PW4)的作用下,α-蒎烯与H2O2反应生成主要产物(3R,4R)-4,7,7-三甲基-6-氧杂二环[3.2.1]辛烷-3,4-二醇。不同反应条件对反应转化率和选择性的实验结果表明,最佳反应条件为:12.8 mmolα-蒎烯、5 m L溶剂三氯甲烷、0.2 g催化剂、3.3 m L 30%H2O2,反应温度40℃,反应时间3 h,α-蒎烯转化率和产物的选择性分别为94.7%和39.8%。反应结束后,该产物存在于水相和有机相中,通过萃取和重结晶分离提纯,得率11%,纯度达到98%;其分子结构通过红外光谱、紫外光谱、1H核磁共振谱、13C核磁共振谱、低分辨率质谱及高分辨率质谱确证。