| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1345920 | Tetrahedron: Asymmetry | 2005 | 10 Pages |
The absolute configuration of secondary alcohols can be determined by NOE between the diastereotopic protons of the lactam and the protons of the alcohol moieties in some 1-(alkoxymethyl)-methyl-2-pyrrolidone-5-carboxylate derivatives. Two simple methods based on conformational analysis and 1H NMR data have been developed. The main conformer, in all cases, was established by means of MM, semi-empirical, and ab initio calculations.
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l-Methyl pyroglutamateC9H9NO3[α]D20=+6.2 (c 2.3, EtOH)
1-[(1R′,2S′,5R′)-Menthoxy-methyl]-methyl-(S)-2-pyrrolidone-5-carboxylateC17H29O4N[α]D20=-105.5 (c 0.578, CHCl3)
1-[(1R′,2S′,5R′)-2-Isopropenyl-5-methyl-cyclohexanoxy-methyl]-methyl-(S)-2-pyrrolidone-5-carboxylateC17H27O4N[α]D20=-83.1 (c 4.8, CHCl3)
1-[endo-(1S)-[1′,7′,7′-Trimethylbicyclo[2.2.1]heptan-2′-oxy-methyl]]-methyl-(S)-2-pyrrolidone-5-carboxylateC17H27O4N[α]D20=-66.8 (c 0.774, CHCl3)
1-[3′-β-Cholest-5′-en-3′-oxy-methyl]-methyl-5-(S)-2-pyrrolidone-5-carboxylateC34H55O4N[α]D20=-55.6 (c 1.86, CHCl3)
1-[17′-β-(1-Ketoethyl)-Δ5′-androsten-3′-β-oxy-methyl]-methyl-5-(S)-2-pyrrolidone-5-carboxylateC28H41O5N[α]D20=-22.8 (c 0.745, CHCl3)
