Department of Chemistry, Box 9573, Mississippi State University, Mississippi State, MS 39762, USA.
Chirality. 2013 Apr;25(4):238-42. doi: 10.1002/chir.22135. Epub 2013 Mar 1.
The chromatographic chiral resolution of 4-aryl-1,4-dihydropyridines (1-32), 4-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidines (33-38), and 4-aryl-2-oxo-1,2,3,4-tetrahydropyrimidines (39-41) was studied on a tetraproline-immobilized chiral column synthesized in our lab. This tetraproline chiral stationary phase can resolve most of these compounds. The 4-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidines (33-38) and 4-aryl-2-oxo-1,2,3,4-tetrahydropyrimidines (39-41) were more efficiently resolved than the racemic 4-aryl-1,4-dihydropyridines on the tetraproline chiralstationary phase. Analytes with 5,5-dimethyl groups (39-41) were less efficiently resolved than analytes without 5,5-dimethyl substituents (1-16). The 4-aryl-2-oxo-1,2,3,4-tetrahydropyrimidines (39-41) without a sulfur atom were much more efficiently resolved than 4-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidines (33-38). No obvious electronic effects on the resolution of any of these analytes (1-41) were observed on the tetraproline chiral stationary phase. The tetraproline chiral stationary phase separated enantiomers mainly via hydrogen bonding interactions.
研究了手性四脯氨酸固定相拆分 4-芳基-1,4-二氢吡啶（1-32）、4-芳基-2-硫代-1,2,3,4-四氢嘧啶（33-38）和 4-芳基-2-氧代-1,2,3,4-四氢嘧啶（39-41）。该手性固定相对大多数化合物具有拆分能力。4-芳基-2-硫代-1,2,3,4-四氢嘧啶（33-38）和 4-芳基-2-氧代-1,2,3,4-四氢嘧啶（39-41）在手性固定相上的拆分效率高于外消旋 4-芳基-1,4-二氢吡啶。带有 5,5-二甲基取代基（39-41）的化合物比没有 5,5-二甲基取代基的化合物（1-16）拆分效率更低。没有硫原子的 4-芳基-2-氧代-1,2,3,4-四氢嘧啶（39-41）比 4-芳基-2-硫代-1,2,3,4-四氢嘧啶（33-38）拆分效率更高。在手性固定相中，这些化合物（1-41）的拆分效率没有明显的电子效应。手性四脯氨酸固定相主要通过氢键相互作用拆分对映异构体。
