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Excellent enantiomer separation of a variety of racemic compounds, including alcohols, amines, amino alcohols, carboxylic acids, hydroxy acids and amino acids, was achieved by GC and HPLC with tripeptide derivatives, containing L-valyl-L-valyl-L-valine isopropyl ester as a chiral selector, bonded to amino silicone oil (CSP-3) and N-(2-aminoethyl)-3-aminopropyl silica gel (CSP-4) via a triazine ring, respectively. These results show that the hydrogen bonding association between solutes and chiral stationary phases (CSPs) can play an important role in chiral recognition in both GC and HPLC. The joint use of two CSPs is promising for the direct separation of racemic compounds.

Fatty acids extracted from archaeological pottery vessels (B.C. 900—720 y) excavated at Tell Mastuma, Syria, are characteristic of individual vessels. The molecular-distribution patterns of n-fatty acids of these vessels are different from those of the underfloor soil and a human hand, indicating that the fatty acids recovered are proper to the samples. The lamps show a predominance of hexadecanoic and octadecanoic acids with a near absence of other acids in the patterns, suggesting that olive oil was used in the lamps. On the other hand, large pottery jars show a clear presence of nonanoic acid in their patterns. The acid presence is also strikingly noted in carbonized olive, suggesting that olive and/or a chemically olive-related material was stored in the jars. The relative concentration of cis-9-octadecenoic acid to octadecanoic acid decreases drastically from modern olive pulp to carbonized olive, and further in the jars and lamps. Apparently, a degradation of the acid had occurred intensely during b...

For the separation of carboxylic acid enantiomers by HPLC, the chromatographic properties of four chiral amide and urea derivatives [ N -3,5- dinitrobenzoyl - d -1-(α- naphthyl)glycine , 3,5- dinitrophenylaminocarbonyl - d - phenylglycine , 3,5- dinitrophenylaminocarbonyl - l - valine and 3,5- dinitrophenylaminocarbonyl - l -tert.- leucine ] covalently bonded to 3-aminopropylsilanized silica gel as chiral stationary phases were examined. Direct separation of various carboxylic acid enantiomers was accomplished with these chiral stationary phases. The influence of the composition of the mobile phase in these enantiomer separations was shown. Amino acid enantiomers were also well resolved in the form of their derivatives containing a free carboxylic acid group, such as tert.-butoxycarbonyl (t-BOC), benzyloxycarbonyl (Z), 9-fluorenylmethoxycarbonyl (FMOC) and 5-dimethylamino-1-naphthalenesulfonyl (dansyl) derivatives.

ガスクロマトグラフィーによるアルコール光学異性体の直接分離のために2種の光学活性固定相,N-サリチリデンー(R)-2-アミノ-1,1-ビス(2-ブトキシ-5-t-ブチルフェニル)-3-フェニル-1-プロパノールの銅錯体[I]及びN-3,5-ジニトロベンゾイル-(D)-フェニルグリシンをアミノシリコンオイルに結合したもの[II]が優れた性能を有することを認めた.脂肪族アルコールやジオール等の光学異性体は固定相[I](10%アミノシリコンオイル溶液)を,又芳香族アルコール等の光学異性体は固定相[II]を塗布した溶融シリカキャピラリーカラムを用いて良好に分離された.固定相[I]は熱安定性が不十分で70℃以上での使用は劣化を速めるが,固定相[II]は熱安定性がよく180℃においても優れた分離能を保持するので,両固定相を併用することにより広い範囲のアルコール光学異性体の分離が可能であり今後の活用が期待される.