Search Results

You are looking at 1 - 4 of 4 items for :

  • "Macrocyclic antibiotic" x
  • Refine by Access: All Content x
Clear All

The chromatographic behavior of five macrocyclic antibiotics (erythromycin, troleandomycin, tylosin, rifamycin B, and rifampicin) has been compared on normal and reversed-phase TLC plates. Mobile phases were wide-ranging mixtures containing from 0 to 100%, ( v/v ), esters or ketones in dimethyl sulfoxide (DMSO) or hexamethyldisiloxane (HMDSO). Chromatographic retention data and a possible retention mechanism are discussed.

Restricted access

The retention behavior of five macrocyclic antibiotics (erythromycin, troleandomycin, tylosin, rifamycin B, and rifampicin) has been examined on RP-18 F 254s TLC plates as stationary phase with a wide range (from 0 to 100%, v/v ) of mixtures of alcohols with dimethyl sulfoxide (DMSO) or hexamethyldisiloxane (HMDSO) as mobile phases. Chromatographic retention data and a possible retention mechanism are discussed.

Restricted access

The retention behavior of selected macrocyclic antibiotics (erythromycin, troleandomycin, tylosin, vancomycin, rifamycin B, and rifampicin) has been examined on LiChrospher Si 60 F 254s HPTLC plates as stationary phase. A wide range of mixtures of alcohols and ketones with hexamethyldisiloxane (HMDSO) in proportions from 0 to 100% ( v/v ) and with dimethyl sulfoxide (DMSO) in proportions from 0 to 50% ( v/v ) were used as mobile phases. Chromatographic retention data and a possible retention mechanism are discussed.

Restricted access

Resolution of the enantiomers of racemic atenolol, metoprolol, propranolol, and labetalol, commonly used β-blockers, has been achieved by TLC on silica gel plates using vancomycin as chiral impregnating reagent or as chiral mobile phase additive. With vancomycin as impregnating agent, successful resolution of the enantiomers of atenolol, metoprolol, propranolol, and labetalol was achieved by use of the mobile phases acetonitrile-methanol-water-dichloromethane 7:1:1:1 ( v/v ), acetonitrile-methanol-water 6:1:1 ( v/v ), acetonitrile-methanol-water-dichloromethane-glacial acetic acid 7:1:1:1:0.5 ( v/v ), and acetonitrile-methanol-water 15:1:1 ( v/v ), respectively. With vancomycin as mobile phase additive, successful resolution of the enantiomers of metoprolol, propranolol, and labetalol was achieved by use of the mobile phases acetonitrile-methanol-0.56 mM aqueous vancomycin (pH 5.5) 6:1:1 ( v/v ), acetonitrile-methanol-0.56 mM aqueous vancomycin (pH 5.5) 15:1:2 ( v/v ), and acetonitrile-methanol-0.56 mM aqueous vancomycin (pH 5.5)-dichloromethane 9:1:1.5:1 ( v/v ), respectively. Spots were detected by use of iodine vapor. The detection limits were 1.3, 1.2, 1.5, and 1.4 μg for each enantiomer of atenolol, metoprolol, propranolol, and labetalol, respectively.

Restricted access