Application of Hydrazino Dinitrophenyl-Amino Acids as Chiral Derivatizing Reagents for Liquid Chromatographic Enantioresolution of Carbonyl Compounds

作者：Bhushan Ravi^*; Dixit Shuchi

来源：Chromatographia, 2011, 74(3-4): 189-196.

DOI：10.1007/s10337-011-2063-x

• Reversed-phase high-performance liquid chromatography
• Chiral derivatizing reagents
• Chiral separation
• Chiral carbonyl compounds
• 1,5-Difluoro-2,4-dinitrobenzene

A new series of chiral derivatizing reagents (CDRs) consisting of five hydrazino dinitrophenyl (HDNP)-amino acids (CDR 1-5) was prepared by a two-step synthesis procedure starting from 1,5-difluoro-2,4-dinitrobenzene (DFDNB). In the first step, five fluoro-dinitrophenyl (FDNP)-reagents, namely FDNP-L-Leu, FDNP-L-Val, FDNP-L-Phe, FDNP-L-Ala and FDNP-D-Phg were synthesized by substituting one of the fluorine atoms in DFDNB moiety with amino acids L-Leu, L-Val, L-Phe, L-Ala and D-Phg, respectively. In the following step, the remaining fluorine atom of the FDNP reagents was substituted with hydrazine hydrate to obtain five HDNP reagents (i.e. CDR 1-5; HDNP-L-Leu, HDNP-L-Val, HDNP-L-Phe, HDNP-L-Ala and HDNP-D-Phg). These five CDRs were used for synthesis of diastereomers of six racemic carbonyl compounds which were resolved by high-performance liquid chromatography using C18 column and gradient eluting mixture of acetonitrile or methanol with triethylammonium phosphate buffer with UV detection at 348 nm. Microwave irradiation was used for synthesis of both the CDRs and the diastereomers. The newly synthesized CDRs were observed to be superior in comparison to their counterparts having amino acid amides as chiral auxiliaries in terms of cost effectiveness and providing better resolution of diastereomers. The method was validated for limit of detection, linearity, accuracy and precision.

• 出版日期2011-8