Sodium isosorbide 5-nitrate

Sodium isosorbide 5-nitrate, containing various different proportions of crystal water, was prepared in 46% yield by adding fuming nitric acid to isosorbide dissolved in a mixture of acetic acid, acetic anhydride, and ben-... 

Since these nitrate-based compounds cause blood vessels to dilate, they are called nitrovasodilators. Nitrovasodilators have clinical utility in the treatment of angina and in the treatment of malignant hypertension (high blood pressure that is severely out of control). Some of the available nitrovasodilator products include amyl nitrite (4.228), nitroglycerin (4.229), isosorbide dinitrate (4.230), erythrityl tetranitrate (4.231), pentaery-thritol tetranitrate (4.232) and sodium nitroprusside (4.233). 

It is now realized that a number of well-known nitrates or nitrite vasodilators work by activating the NO pathway. Some of these used in therapeutics include amyl nitrate, glyceryl trinitrate, isosorbide dinitrate, pentaerythritol tetrahitrate, sodium nitrate, sodium nitrite and sodium nitroprusside. Also, agents used as NO donors include molsidomine and 5-nitroacetylpenicillamine. 

Vasodilators have a number of different mechanisms of action. Some are smooth muscle relaxants that act directly on the blood vessels, e.g. glyceryl trinitate, hydralazine, isosorbide dinitrate, pentaerythritol tetranitrate, sodium nitroprusside and other nitrite and nitrate drugs, which are thought to mimic the actions of the endogenous mediator nitric oxide, which relaxes smooth muscle through elevation of cGMP (see nitrergic stimulants). 

Organic nitrates (eg, nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate) are widely used as vasodilators for the treatment of ischemic heart disease and heart failure. Organic nitrates such as nitroglycerin are also used in explosives. Bismuth subnitrate, ammonium nitrate, and silver nitrate are used in antidiarrheal dmgs, cold packs, and topical bum medications, respectively. Sodium and potassium nitrate and nitrite are used in preserving cured foods and may also occur in high concentrations in some well water. Butyl, amyl, ethyl, and isobutyl nitrites are often sold as room deodorizers or liquid incense and are sometimes inhaled for abuse purposes. 

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