5297-17-6Relevant articles and documents
Degradation properties and pH-responsive guest-release of cyclophanes having four ester side chains with terminal choline residues
Hayashida, Osamu,Sato, Daisuke
supporting information, p. 322 - 324 (2014/03/21)
Water-soluble cationic cyclophane 1 having four ester side chains with terminal choline residues was synthesized as a pH-responsive degradable host. Alkaline hydrolysis of the ester bonds of 1 gave the corresponding tetraanionic cyclophane 2, which exhibited guest-binding affinities that led to release of the entrapped anionic guest molecules into the bulk aqueous phase.
Analysis and stability of suxamethonium chloride. 1. Detection and quantitative determination of the intact active agent with its degradation products
Doege,Pohloudek-Fabini,Kottke
, p. 708 - 711 (2007/10/02)
The authors developed methods permitting to follow the course of degradation in injectable solutions of suxamethonium chloride. The qualitative detection of the active agent in the presence of degradation products is achieved by thin-layer chromatography and spraying with Dragendorff's reagent and bromocresol green indicator solution. The same separation technique may be used for determining with sufficient accuracy the intact agent in the eluate, using the method of Okken and Haas. Furthermore, a modified Draganic procedure (which is based on the spectrophotometric determination of the hydrolysis products succinic acid monocholine chloride and succinic acid as a Cu-benzidine complex) is suited for estimating the degree of degradation. No previous separation is required because the molar extinction efficients of the monoester and of the acid are in agreement, so that the degree of degradation can be calculated from the sum of the molar concentrations. The value of these methods is demonstrated by analyzing experimental mixtures of the intact agent and degradation products.