The use of Mg and Ca hydride catalysts for the 4e– reduction of CO2 is reported. Borabicyclo[3.3.1]nonane (9-BBN) and dicyclohexylborane (HBCy2), as reductants, led to the generation of the corresponding bis(boryl)acetal (BBA) which in situ reacted with thiol to afford new borylated hemithioacetal compounds (R2BOCH2SR) undermild neutral conditions. These hemithioacetals were then converted into dithioacetal
据报道,使用氢化镁和氢化钙催化剂进行 4e还原CO 2 。硼双环[3.3.1]壬烷(9-BBN)和二环己基硼烷(HBCy 2)作为还原剂,导致生成相应的双(硼基)缩醛(BBA),其与硫醇原位反应,得到新的硼基化半硫缩醛化合物( R 2 BOCH 2 SR)在温和中性条件下。然后,通过在酸性活化下添加第二当量的硫醇,将这些半硫缩醛转化为二硫缩醛(RSCH 2 SR),或者在与仲胺反应后转化为氨基甲基硫醚(RSCH 2 NR 2 )。
GABRIEL, J.;SEEBACH, D., HELV. CHIM. ACTA, 1984, 67, N 4, 1070-1082
作者:GABRIEL, J.、SEEBACH, D.
DOI:——
日期:——
NMR spectroscopic studies of intermediary metabolites of cyclophosphamide. A comprehensive kinetic analysis of the interconversion of cis- and trans-4-hydroxycyclophosphamide with aldophosphamide and the concomitant partitioning of aldophosphamide between irreversible fragmentation and reversible conjugation pathways
作者:Gerald Zon、Susan Marie Ludeman、Joan A. Brandt、Victoria L. Boyd、Gunay Ozkan、William Egan、Kai Liu Shao
DOI:10.1021/jm00370a008
日期:1984.4
and 7.8 were equal to 0.030 +/- 0.004, 0.090 +/- 0.008, and 0.169 +/- 0.006 min-1, respectively. Replacement of the HC(O)CH2 moiety n 3 with HC(O)CD2 led to a primary kinetic isotope effect (kH/kD = 5.6 +/- 0.4) for k3. The apparent half-lives (tau 1/2) for cis-2, "3", and trans-2 under the standard reaction conditions, at "pseudoequilibrium" (constant ratio of cis-2/"3"/trans-2), were each equal to approximately
多核(31P,13C,2H和1H)傅立叶变换NMR光谱,无论有没有同位素富集的材料,都被用来鉴定和量化抗癌前药的以下中间(短时)代谢产物(随时间变化)环磷酰胺(1,方案I):顺式-4-羟基环磷酰胺(cis-2),其反式异构体(trans-2),醛基磷酰胺(3)和其醛-水合物(5)。在一组标准反应条件下(1 M 2,6-二甲基吡啶缓冲液,pH 7.4,37摄氏度),用4当量的硫代硫酸钠(4当量)合成顺式4-氢过氧环磷酰胺(顺式12,20 mM)的立体定向脱氧Na2S2O3)在大约20分钟后提供了cis-2、3、5和trans-2的“伪平衡”分布,即这些反应物的相对比例(57:4:9:30,在持续消失的过程中保持不变。没有检测到指示“亚氨基磷酰胺”(8)和烯醇6的NMR吸收信号(少于合成代谢物混合物的0.5-1%)。将计算机最小二乘拟合程序应用于各个31P NMR衍生的时间过程,以将cis-2、3加5(即“
Synthesis of isotopically labeled 1,3-dithiane
作者:Rodolfo A. Martinez、David R. Glass、Erick G. Ortiz、Marc A. Alvarez、Clifford J. Unkefer
DOI:10.1002/jlcr.3185
日期:2014.5.15
could serve as a useful labeled synthon. We report a facile synthesis of 1,3-[2-(13)C]- and 1,3-[2-(13)C, 2-(2)H2]dithiane in two steps from [(13)C]- or [(13) C, (2)H3 ]methyl phenyl sulfoxide. We have previously reported the high yield synthesis of [(13)C]methyl phenylsulfide from [(13)C]MEOH and the oxidation of [(13)C]methyl phenylsulfide to [(13)C]methyl phenyl sulfoxide. Here, we describe the