The first total synthesis of （+）-5α-hydroxy-isopterocarpolone （1）, an oxygenated eudesmane isolated from Chinese folk medicine Artemisia eriopoda, starting from （+）-dihydrocarvone（2） was described. Compound 4...The first total synthesis of （+）-5α-hydroxy-isopterocarpolone （1）, an oxygenated eudesmane isolated from Chinese folk medicine Artemisia eriopoda, starting from （+）-dihydrocarvone（2） was described. Compound 4 was stereoselectively prepared from compound 2 in three steps according to reference-. The treatment of tosylhydrazone 5, which was formed via the reaction of compound 4 and TsNHNH2 catalyzed by BF3-5Et2O, with an excess of n-butyllithium gave triene 6. Oxidation of triene 6 with singlet oxygen afforded the desired endo-peroxide 7 as a single product. Reductive cleavage of peroxide 7 with K2CO3 gave α-rotunol 3, a natural eudesmane firstly isolated in 1969. Hydrolysis of α-rotunol 3 with 10% sulfuric acid afforded （+）-5α-hydroxy-isopterocarpolone （1）. The structures of all the compounds were confirmed by IR, MS and NMR spectra.展开更多
2-氟-5-[(4-氧代-3,4-二氢二氮杂萘-1-基)甲基]苯甲酸是合成奥拉帕尼的关键中间体。以邻羧基苯甲醛为原料,与亚磷酸二甲酯反应得到磷叶立德,再与2-氟-5-甲酰基苯甲酸进行WittigHorner反应、环合反应得到目标化合物,并对各步反应条件进...2-氟-5-[(4-氧代-3,4-二氢二氮杂萘-1-基)甲基]苯甲酸是合成奥拉帕尼的关键中间体。以邻羧基苯甲醛为原料,与亚磷酸二甲酯反应得到磷叶立德,再与2-氟-5-甲酰基苯甲酸进行WittigHorner反应、环合反应得到目标化合物,并对各步反应条件进行了优化,三步反应总收率70.9%。目标化合物经(1 H NMR)和(MS)确证结构。展开更多
A series of 2 amimo 3 cyano 7,7 dimethyl 4 aryl 5 oxo 5,6,7,8 tetra 4H chromenes were synthesized in the absence of catalyst. Their structures were determined by IR, 1H NMR, and single crystal X ray diffraction.
Nucleoside reverse transcriptase inhibitors are the only drugs so far approved for the treatment of AIDS. Several nucleoside analogs are potent inhibitors of human immunodeficiency virus(HIV) in cell culture. However,...Nucleoside reverse transcriptase inhibitors are the only drugs so far approved for the treatment of AIDS. Several nucleoside analogs are potent inhibitors of human immunodeficiency virus(HIV) in cell culture. However, in many cases the nucleoside derivatives have a poor affinity for nucleoside kinases. Nucleoside 5′-phosphorothioates is relatively resistant to enzymatic transformations. In this paper, 2′,3′-O-alkoxymethylidene adenosine 5′-thiophosphoramidates were synthesized through a highly efficient approach. The new compounds were characterized by NMR, IR and ESI-MS.展开更多
文摘The first total synthesis of （+）-5α-hydroxy-isopterocarpolone （1）, an oxygenated eudesmane isolated from Chinese folk medicine Artemisia eriopoda, starting from （+）-dihydrocarvone（2） was described. Compound 4 was stereoselectively prepared from compound 2 in three steps according to reference-. The treatment of tosylhydrazone 5, which was formed via the reaction of compound 4 and TsNHNH2 catalyzed by BF3-5Et2O, with an excess of n-butyllithium gave triene 6. Oxidation of triene 6 with singlet oxygen afforded the desired endo-peroxide 7 as a single product. Reductive cleavage of peroxide 7 with K2CO3 gave α-rotunol 3, a natural eudesmane firstly isolated in 1969. Hydrolysis of α-rotunol 3 with 10% sulfuric acid afforded （+）-5α-hydroxy-isopterocarpolone （1）. The structures of all the compounds were confirmed by IR, MS and NMR spectra.
文摘2-氟-5-[(4-氧代-3,4-二氢二氮杂萘-1-基)甲基]苯甲酸是合成奥拉帕尼的关键中间体。以邻羧基苯甲醛为原料,与亚磷酸二甲酯反应得到磷叶立德,再与2-氟-5-甲酰基苯甲酸进行WittigHorner反应、环合反应得到目标化合物,并对各步反应条件进行了优化,三步反应总收率70.9%。目标化合物经(1 H NMR)和(MS)确证结构。
文摘A series of 2 amimo 3 cyano 7,7 dimethyl 4 aryl 5 oxo 5,6,7,8 tetra 4H chromenes were synthesized in the absence of catalyst. Their structures were determined by IR, 1H NMR, and single crystal X ray diffraction.
文摘Nucleoside reverse transcriptase inhibitors are the only drugs so far approved for the treatment of AIDS. Several nucleoside analogs are potent inhibitors of human immunodeficiency virus(HIV) in cell culture. However, in many cases the nucleoside derivatives have a poor affinity for nucleoside kinases. Nucleoside 5′-phosphorothioates is relatively resistant to enzymatic transformations. In this paper, 2′,3′-O-alkoxymethylidene adenosine 5′-thiophosphoramidates were synthesized through a highly efficient approach. The new compounds were characterized by NMR, IR and ESI-MS.
