Synthesis of Monodisperse Macromolecular Bicyclic and dendritic compounds from (R)-3-hydroxybutanoic acid and benzene-1,3,5-tricarboxylic acid and analysis by fragmenting MALDI-TOF mass spectroscopy
作者:Dieter Seebach、Guide F. Herrmann、Urs D. Lengweiler、Walter Amrein
DOI:10.1002/hlca.19970800402
日期:1997.6.30
elemental analysis. Especially important is the analysis by mass spectrometry with the MALDI-TOF technique (Fig. 2), proving that the products are monodisperse; application of a new variation of this MS method (post source decay = PSD or fragment analysis by structural time of flight = FASTTM) allows for the observation of metastable fragment ions and, thus, is a tool for structural oligomer analysis (Fig
如前所示,低聚和聚(β-羟基链烷酸酯)很容易形成具有ca的层状微晶。50-Å的厚度,对应于16个单元的链长(图1)。具有单分散的模型化合物,我们现在已经制备双环衍生物与三个平行(27 - 29)或两个平行和反平行链(68 - 70)由最多至16 3-羟基丁酸(3-HB)单元。我们还制备树枝状化合物(71 - 75,82 - 85)含有不可能被布置为在低聚(3-HB)链薄片; 支链单元由均苯三酸(=苯-1,3,5-三羧酸)制备。到目前为止,没有一个准备好的样品能够形成晶体或包含适合单晶或粉末衍射X射线分析的晶畴。的末端脱保护的树枝状聚合物(74,75,和85)是多阴离子(最多12个CO 2 H基团)和可生物降解的。通过IR,1 H-和13 C-NMR,[α] D和元素分析已充分表征了大分子HB衍生物(分子量高达10150 Da)。尤其重要的是使用MALDI-TOF技术进行的质谱分析(图2),