Supramolecular dynamics of thalidomide and its derivatives in water‐sediment system

Abstract

The contamination of drug residues, including chiral ones, is not acceptable in earth's ecosystem. The dynamicity of enantiomers of thalidomide and its derivatives (3-methyl thalidomide, 3-ethyl thalidomide, and 3-butyl thalidomide) was ascertained at supramolecular level in water-sediment system using solid phase extraction (SPE) and stereoselective HPLC. Enantiomeric separation of these drugs was carried out on Ceramosphere RU-2 (25 cm 3 0.46 cm, particle size 50 lm) chiral column using pure ethanol (1.0 ml/min) as eluent at 230 nm detection. Retention times, capacity, separation, and resolution factors of the enantiomers of these drugs were in the range of 20.0-36.0, 2.08-3.93, 1.35-1.57, and 1.0-2.0 min, respectively. Percentage recoveries of the enantiomers in SPE were in the range of 90.0 to 95.0 in water-sediment system. Langmuir and Freundlich model were best fitted for dynamic equilibrium concentrations at different experimental parameters. Thalidomide and its derivatives follow first-order kinetics at dynamic equilibrium. The rate constants of chiral interconversions were 0.390 and 0.385 days 21 for S-and R-enantiomers, respectively. The uptake of thalidomide by sediment is quite good and of endothermic nature indicating good self-purification capacity of the nature for such toxic species. Chirality 00:000-000, 2009. V V C 2009 Wiley-Liss, Inc.

Chiral Separations: A Review of Current Topics and Trends

“…59 Chiral resolution of thalidomide and its derivatives in water sediment was achieved on a Ceramosphere RU-2 CSP which employs a chiral ruthenium complex trapped in a zeolite structure. 60 This CSP was used in a study of supramolecular dynamics. A crown ether tetracarboxylic acid CSP, Chirosil RCA(+), was used in the enantioseparation of aromatic amines and aromatic amino alcohols, with a discussion of the relationship between retention, enantioselectivity, and molecular structure.…”

“…A CSP derived from 4-(3,5-dinitrobenzamido)tetrahydrophenanthrene was used in the enantioresolution of mandelic acid and its analogs, with suggested chiral recognition models also presented . Chiral resolution of thalidomide and its derivatives in water sediment was achieved on a Ceramosphere RU-2 CSP which employs a chiral ruthenium complex trapped in a zeolite structure . This CSP was used in a study of supramolecular dynamics.…”

Enantioselective degradation of dufulin pesticide in water: Uptake, thermodynamics, and kinetics studies

“…Among many pesticides, some are chiral in nature and exist in racemic form. The two enantiomers have different insecticidal activities and biodegradation in the environment . The rising alerts on the side effects of chiral chemicals on nontarget animals, human beings and ecology, the researchers, academicians, and Government authorities are promoting the use of enantiomerically pure agrochemicals .…”

“…The two enantiomers have different insecticidal activities and biodegradation in the environment. [19][20][21][22][23][24][25][26][27] The rising alerts on the side effects of chiral chemicals on nontarget animals, human beings and ecology, the researchers, academicians, and Government authorities are promoting the use of enantiomerically pure agrochemicals. Therefore, it is essential to study the sorption and biodegradation of racemic and enantiomeric pesticides to determine their fates in the ecology.…”