Reference

The application of HPLC chiral stationary phases to pharmaceutical analysis: the resolution of some tropic acid derivatives

The application of HPLC chiral stationary phases to pharmaceutical analysis: the resolution of some tropic acid derivatives. Wainer, Irving W.; Doyle, Thomas D. 90902-30-0 which is the cas registry number is also used here.; Breder, Christopher D. (Div. Drug Chem., Food Drug Adm., Washington, DC 20204, USA). J. Liq. Chromatogr., 7(4), 731-41 (English) 1984. CODEN: JLCHD8. ISSN: 0148-3919. DOCUMENT TYPE: Journal CA Section: 64 (Pharmaceutical Analysis) Section cross-reference(s): 25, 27 The resoln. of amides and esters of tropic acid PhCH(COR2)CH2OR1 [I, R1 = H or Ac, R2 = 1-naphthylmethylamino, 1-naphthylmethyl or N-ethyl-N-(4-pyridinylmethyl)amino or 3-tropyl] was investigated by HPLC with a chiral stationary phase, (R)-N-(3,5-dinitrobenzoyl)phenylglycine [74927-72-3]. The amide derivs. were easily resolved on the column. The sepn. factor was around 1:1. The esters could not be resolved on the column under the conditions used for the sepn. of the amides. The anticholinergic agent, tropicamide [I, R1 = H and R2 = N-ethyl-N-2-(4-pyridylmethyl)amino] [1508-75-4], was resolved directly on the column without derivatization and the capacity factor was 1.03. The mechanism and the reasons for the sepn. are given. .

Surface spreading and viscous effects in human ophthalmic bioavailability - the behavior of tropicamide in different polymeric vehicles

Surface spreading and viscous effects in human ophthalmic bioavailability - the behavior of tropicamide in different polymeric vehicles. Saettone, M. F.; Giannaccini, B.; Ravecca, S.; La Marca, F.; Tota, G. (Eye Clin., Univ. Pisa, Pisa 56100, Italy). Biopharm. Pharmacokinet., Eur. Congr., 2nd, Volume 1, 620-6. Edited by: Aiache, J. M.; Hirtz, J. Lavoisier: Paris, Fr. (English) 1984. CODEN: 53JFAA. DOCUMENT TYPE: Conference CA Section: 63 (Pharmaceuticals) Section cross-reference(s): 1 5 Viscous polymeric vehicles contg. 0.2% tropicamide (I) [1508-75-4] were tested for mydriatic activity in humans. The polymers were CM-cellulose (CMC) [9004-32-4], low-mol. wt. hydroxypropyl cellulose (HPCL) [9004-64-2], medium-mol. wt. hydroxypropyl cellulose (HPCM), poly(vinylpyrrolidone) (PVP) [9003-39-8] and poly(vinyl alc.) (PVA) [9002-89-5]. Their concns. were adjusted to give isoviscous (70 CP) Newtonian solns. (HPCL, PVP, PVA) or pseudoplastic solns. with an apparent viscosity of 70 cP at a shear rate of 700 s-1. All vehicles increased the ocular bioavailability of the drug, respect to a nonviscous soln. PVP and PVA were significantly more active than the other polymers. The different activity of the polymers could neither be correlated with drug binding, nor with surface or interfacial tension, nor with the rheol. behavior of the solns. polymers (PVA, PVP) may affect the ocular bioavailability of I not by viscous effects alone, but also by affecting the spreading characteristics and the thickness of the medication layer over the precorneal area.