One unknown impurity(Imp-II)during the analysis of laboratory batches of isoproterenol hydrochloride was detected in the level ranging from 0.04% to 0.12% by high performance liquid chromatography with UV detection. The unknown impurity structure was proposed as 4-[2-(propan-2-ylamino)ethyl]benzene-1,2-diol (Imp-Ⅱ)using the liquid chromatography–mass spectrophotometry(LC–MS)analysis.Imp-Ⅱ was isolated by semi-preparative liquid chromatography from the impurity-enriched reaction crude sample. Its proposed structure was confirmed by nuclear magnetic spectroscopy such as 1H, 13C,DEPT(1D NMR),HSQC(2D NMR) and infrared spectroscopy(IR),and retention time and purity with HPLC followed by the chemical synthesis. Due to less removable nature of Imp-II during the purification,the synthetic process was optimized proficiently to control the formation of Imp-II below to the limit<0.12% in the course of reaction.The new chemical route was developed for the preparation of this impurity in required quantity with purity to use as reference standard. The most probable mechanism for the formation of Imp-II was discussed in details.

No abstract available.
Arteries ; Catheterization ; Embolization, Therapeutic/*methods ; Enbucrilate/*therapeutic use ; Esophageal Diseases/*therapy ; Esophagus/blood supply ; Gastrointestinal Hemorrhage/*therapy ; Hemostatics/*therapeutic use ; Humans ; Treatment Outcome

Therapeutic embolization is defined as the voluntary occlusion of one or several vessels, and this is achieved by inserting material into the lumen to obtain transient or permanent thrombosis in the downstream vascular bed. There are a number of indications for this approach in urological practice, in particular for the patients with parenchymatous or vascular kidney disease. In this review, we present the different embolization techniques and the principally employed occluding agents, and then we present the principal clinical indications and we discuss other pathologies that may benefit from this non-invasive therapy. The complications, side effects and main precautions associated with this approach are also described.
Adenocarcinoma/*therapy ; Aneurysm/therapy ; Angiomyolipoma/*therapy ; Embolization, Therapeutic/*methods ; Humans ; Kidney/injuries ; Kidney Diseases/*therapy ; Kidney Neoplasms/*therapy