共查询到19条相似文献,搜索用时 62 毫秒
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以2-溴丙酸和N-叔丁氧羰基-O-苄基-L-丝氨酸为起始试剂首先制得N-(2-溴丙基)-O-苄基-L-丝氨酸(BPBS), 在N,N-二甲基甲酰胺(DMF)/三乙胺(Et3N)溶剂中80 ℃经9 h后BPBS发生分子内环化反应生成(3S,6S)-3-苄氧甲基-6-甲 基-吗啉-2,5-二酮[(3S,6S)-BMMD]及(3S,6R)-BMMD共存体, 产率70%. 将所制得的共存体以乙酸乙酯为重结晶溶剂, 采用微分重结晶法, 经4次“溶解-部分重结晶”操作循环制得两种纯光学构型的(3S,6S)-BMMD和(3S,6R)-BMMD. 将两种光学纯双手性中心的BMMD分别溶于乙酸乙酯, 室温下培养得(3S,6S)-BMMD和(3S,6R)-BMMD的单晶体, 以X射线衍射法测定上述两种BMMD的分子结构. 相似文献
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改进了沙格列汀中间体3-羟基-1-金刚烷甲基酮(1)的合成路线。以金刚烷甲酸(2)为起始原料,经二氯亚砜酰氯化后与N-氯代琥珀酰亚胺(NCS)反应制得3-氯-1-金刚烷甲酰氯(3); 3依次经取代,脱羧和与碱反应合成1,其结构经1H NMR, IR和MS(ESI)确证。采用星点设计-效应面法对1合成条件进行了优化。结果表明:在最佳反应条件[2 28 mmol, n(NCS)/n(2)/n(AIBN)=1/0.83/0.65,于65 ℃反应8 h]下,1收率70%。 相似文献
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价廉易得的L-亮氨酸先以苄基同时保护氨基及羧基得(S)-2-(二苄胺基)-4-甲基戊酸苄酯,进而在碱性条件下与乙腈发生亲核取代反应得(S)-4-(二苄胺基)-6-甲基-3-氧代庚腈,再经硼氢化钠选择性还原羰基得(3S,4S)-4-(二苄胺基)-3-羟基-6-甲基庚腈,用双氧水氧化得(3S,4S)-4-(二苄胺基)-3-羟基-6-甲基庚酸,最后在Pd(OH)2/C-H2作用下脱掉苄基得到(3S,4S)-4-氨基-3-羟基-6-甲基庚酸,即(3S,4S)-statine。整个合成路线总产率为33.6%。 相似文献
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The central V atom in bis[6-methyl-4-hydroxy-3-quinolinecarboxylate] mono(oxo)mono-hydroxy-vanadium(Ⅴ) (1), synthesized by the hydrothermal treatment of ethyl 6-methyl-4-hydroxy-3-quinolinecarboxylate and V2O5, has a distorted octahedral coordination geometry formed by six oxygen atoms from two oxygen atom of two hydroxy groups and two oxygen atoms of two carboxylate groups as well as one oxo group and hydroxy group. CCDC: 285592. 相似文献
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由6-羟基-2-苯基-3-哒嗪酮和二丁基氧化锡合成了新的有机锡氧簇化合物Ⅰ,用元素分析、IR、1H、13C和119Sn NMR表征了其结构。由X射线单晶衍射测定了其晶体结构,该化合物属于三斜晶系,P1空间群,晶体学参数为a=1.221 75(13)nm,b=1.267 90(13)nm,c=1.345 33(14)nm,α=87.168 0(10)°,β=672.265 0(10)°,γ=87.261 0(10)°,V=1.981 4(4)nm3,Z=1,Dc=1.435 g/cm3,μ(MoKα)=0.870 0,F(000)=868。该化合物具有中心对称的梯形结构,锡原子为五配位的三角双锥构型。该化合物催化乙酰乙酸乙酯和甲醇的酯交换的产率为88%、催化丙二酸二甲酯和乙醇的酯交换的产率为90%,但较难催化环己酮和甘油的缩酮反应,产率低于22%。 相似文献
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《Analytical letters》2012,45(9-10):925-938
Abstract The electrochemical oxidation of [CH3COIII(salen)S]at a platinum electrode was studied, at differnent temperatures, in dimethlyformamide, dimethlacetamide, formamide, propylene carbonate, diemthylslforxide, acetone, hexamthylphosphoranmide and tetrahydrofurn, with 0.5 M NaClo4 as supporting edlctrolyte. The overall electorde process may be described as an ECE type. the anodic peak potentials measured on teh ferrocene/ferrocinium scale, and the decoposition rate constants of the oxidized species, are correlated with the Gutamnn donacity numbers. 相似文献
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An efficient procedure for conversion of alcohols to the corresponding carbonyl compounds, an alternative to the classical Swern oxidation, is described. Pivaloyl chloride is employed as a mild and inexpensive electrophile. A possible reaction mechanism is proposed. 相似文献