Determination of absolute configuration in 4-aryl-3,4-dihydro-2(1H)-pyrimidones by high performance liquid chromatography and CD spectroscopy

3,4-Dihydropyrimidin-2(1H)-ones as Antagonists of the Human A2B Adenosine Receptor: Optimization, Structure–Activity Relationship Studies, and Enantiospecific Recognition

“…Figure shows the results of our joint approach using chiral high-performance liquid chromatography (HPLC) and CD spectroscopy. As recently documented by our own results with structurally related Biginelli-like systems , as well as for other pharmacologically active 3,4-dihydropyrimidin-2-ones/thiones, − the sign of the distinctive CD activity of the enamide group (around 300 nm) allows the unequivocal assignment of the absolute configuration of each enantiomer (Figure ). Semipreparative HPLC separation of the selected racemic ligands [(±)- 38 and (±)- 47 ] on a chiral stationary phase (Figure and Experimental Section) afforded each enantiomer with excellent stereochemical purity (97 and 99% respectively).…”

Design and Synthesis of a Conformationally Rigid Mimic of the Dihydropyrimidine Calcium Channel Modulator SQ 32,926

“…In addition, in order to the test the binding site model depicted in Figure 1 it will be necessary to access enantiomerically pure 3 with known absolute configuration. Work along these lines is currently in progress in our laboratories [29].…”

Atropisomerism inN1‐aryl Substituted 3,4‐dihydropyrimidin‐2(1H)‐thiones

“…For compounds 11 (R=2‐ClPh) and 10 (R=2‐CH 3 OPh) chromatograms B and C displayed non well‐resolved peaks and the peaks ratios can hardly be associated with the NMR findings [20a,b] . For DHPM 17 , which contains no substituent at the aromatic ring linked to N1, only the two pairs of enantiomers were detected in the ratio of 52.8 : 47.1, as showed in Figure 4D [23]…”