Sodium nitroprusside structure

Sodium nitroprusside was first prepared and investigated in the middle of the nineteenth century, and a comprehensive summary of the earlier chemical investigations has been published (17). Up to 1910-1930, the addition reactions of bases to NP were explored, involving the characterization of colored intermediates (e.g., with SH-, SR-, and SO3 ), useful for analytical purposes. The hypotensive action of NP was first demonstrated in 1929, and a considerable research effort has attempted to establish the mode of action of NP and its metabolic fate. Questions still arise on the mechanism of NO release from NP in the biological fluids, and we refer to them below. New accounts dealing with modern structural and reactivity issues associated with the coordination of nitrosyl in NP and other complexes have appeared (18-20). From the bioinorganic and environmental viewpoint, nitrosyl iron complexes have been studied with... 

Structure-activity relationship. The endothelium-independent vasodilator effects showed by flavonoids are related to the structure of the compound tested. Structure- activity relationships have been studied to flavonoids selected from five groups flavonols, flavones, flavanones, isoflavones, and flavanols in rat isolated aorta on the contractions induced by noradrenaline, KC1 and the phorbol ester derivative PMA, as well as the interactions of these flavonoids with isoprenaline and sodium nitroprusside, Table (2). 

During the last decade, the fascinating phenomena of the photochromic effect became a hot problem of molecular structure and spectroscopy due to its promising application in the design of new memory storage systems at the molecular level. This phenomenon has been discovered and studied in several nitrosyl complexes of transition metal ions [1-6]. At low temperatures, the most extensively studied sodium nitroprusside Na2[Fe(CN)5(NO)] 2H2Q (SNP) demonstrates two excited... 

The yellow solid Na4[Fe(CN)5N03] is prepared by the reaction of concentrated aqueous NaOH with a methanolic solution of sodium nitroprusside at 2 °C. The kinetics of the hydrolysis equilibrium (14) have been investigated." [Fe(CN)5H20p is also the usual product in the reaction of nitroprusside ion with ketones, and molecules containing active methylene groups, in alkaline solution. The reaction with acetone has been studied in some detail and the overall reaction in Scheme 1 proposed. Salts of the type (2) shown in Scheme 1 can be isolated. The red ion [Fe(CN)5N(0)CHC0Ph] - formed in the reaction of nitroprusside with acetophenone can be protonated to yield a blue, isolable complex thought to have structure (3). 

The main evidence for the thiazoline structure is the negative test for —SH groups given with the sodium nitroprusside reagent. 

When a secondary amine is treated with sodium nitroprusside (Na2[Fe(CN)5NO]) in the presence of acetaldehyde, acetone, pyruvic acid, etc., blue to violet compounds of unknown structure are obtained This is the so-called Rimini test . A colourimetric... 

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