Tetranitrate tablets

Cognate Assays The following two pharmaceutical products, namely Pentaerythritol tetranitrate Tablets and Diluted Isosorbide dinitrate are assayed by using a solution of phenoldisulphonic acid as detailed below ... 

Pentaerythyritol tetranitrate Tablets 50 mg 405 nm Each ml of KN03 soln. =0.5 mg ofC5H8N4012... 

Carlson, M. Thompson, R.D. Determination of pentaeiythritol tetranitrate in pharmaceuticals hy high performance liquid chromatography. J.Liq.Chromatogr., 1988, 11, 2603-2620 [simultaneous pen-taerythritol tetranitrate tablets capsules nitroglycerin is IS]... 

The use of nitroglycerine tablets has been known for several decades to dilate the blood vessels promptly thereby decreasing the blood pressure and thus giving instant relief from angina. However, the present trend is to use other esters of nitric acid such as erythritol tetranitrate, mannitol hexanitrate, PETN and other similar derivatives instead of NG for this purpose. These nitric acid esters being crystalline, are not assimilated readily and therefore, act more slowly but produce a longer lasting effect. 

Symmetric carbonates of guaiacol or ethyl salicylate are crystalline solids (Figure 41.12), pentaerythritol tetranitrate is the solid counterpart of the liquid trinitrine and petrichlo-ral is again a stabilized chloral derivative. Methenamine, formulated as an enteric-coated tablet, is used as a urinary tract antibacterial. Following absorption, the compound is eliminated in the urine where formaldehyde is generated in the acidic environment. 

Sample preparation Powder tablets, weigh out a portion equivalent to 3 mg erythrityl tetranitrate, add to 10 mL 75 p mL nitroglycerin in MeOH, sonicate for 2 min, shake mechanically for 30 min, filter, inject an aliquot... 

Olsen, C.S. Scroggins, H.S. High-performance liquid chromatographic determination of the nitrate esters isosorhide dinitrate, pentaerythritol tetranitrate, and erythrityl tetranitrate in various tablet forms. J.Pharm.Sci, 1984, 73, 1303-1304... 

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