Spontaneous generation and amplification of optical activity in α-amino acids by enantioselective occlusion into centrosymmetric crystals of glycine
Spontaneous generation and amplification of optical activity in α-amino acids by enantioselective occlusion into centrosymmetric crystals of glycine
复制标题
通过对映选择性封闭甘氨酸的中心对称晶体来自发产生和放大 α-氨基酸的光学活性
DOI：
10.1038/310161a0
复制
发表时间：
1984
期刊：
影响因子：
64.8
通讯作者：
L. Leiserowitz
中科院分区：
文献类型：
--
作者：
I. Weissbuch;L. Addadi;Z. Berkovitch;E. Gati;M. Lahav;L. Leiserowitz
最近的研究晶体生长中存在的特定添加剂提出了一种新的方法来产生和放大的光学活性在最初的外消旋mixtures 1 -4。这种方法是基于这样的观察，即特定的对映异构体不仅可以选择性地掺入手性晶体5 -7，而且还可以掺入中心对称晶体3，4，8的相对对映异构体面。因此，如果中心对称晶体的一个这样的面被封闭，则对映选择性封闭到相对面中将优先从外消旋混合物中除去一种对映体。我们在这里报告说，这个过程可以发生与中心对称晶体的甘氨酸，在某种程度上，可能是相关的生物前进化过程中产生的光学活性。甘氨酸晶体漂浮在溶液中，因此只有一个面可用于生长。疏水性氨基酸的特定对映体的添加以这样的方式使漂浮晶体定向，使得封闭相反手性的氨基酸的面暴露于溶液。因此，在最初的外消旋溶液中漂浮的晶体的取向的统计波动可能导致旋光性的产生和放大。
Recent studies of crystal growth in the presence of specific additives have suggested a new approach to the generation and amplification of optical activity in initially racemic mixtures1–4. This approach is based on the observation that particular enantiomers can be selectively incorporated not only into chiral crystals5–7 but also into the opposite enantiotopic faces of centrosymmetric crystals3,4,8. If one such face of a centrosymmetric crystal is blocked, therefore, enantioselective occlusion into the opposite face will remove one enantiomer preferentially from the racemic mixture. We report here that this process can take place with centrosymmetric crystals of glycine, in a way that may be of relevance to the generation of optical activity during prebiotic evolution. Glycine crystals float in solution, such that only one face is available for growth. The addition of a particular enantiomer of a hydro-phobic amino acid orientates the floating crystals in such a way that the face that occludes amino acids of the opposite chirality is exposed to the solution. Thus, a statistical fluctuation in the orientation of crystals floating in an initially racemic solution could lead to the generation and amplification of optical activity.