Creatinine guanidine derivatives

Modem Alkaloids Structure, Isolation, Synthesis and Biology. Edited by E. Eattorusso and O. Taglialatela-Scafati Copyright 2008 WILEY-VCH Veriag GmbH Co. KGaA, Weinheim ISBN 978-3-527-31521-5 

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Polycyclic compound 478, which forms stable complexes with urea, guanidine, amidines and their derivatives, is covered by patents (1991USP15030728, 1994USP5283333). These complexes were used in a biological investigation. Receptor betaine molecule 479 was constructed for diagnostic tests for blood (serum) creatinine and renal insufficiency. 

The fluorescence of a ninhydrin derivative of creatine can be used to determine creatine concentrations in blood and urine. Protein and arginine are precipitated by treatment with barium hydroxide and zinc sulfate, and after addition of ninhydrin the solution is made basic and the fluorescence excited at 390 nm is monitored at 495 nm.Creatinine and phosphocrea-tine do not form fluorescent derivatives, but some guanidine compounds can interfere, although they are not normally present in significant amounts. 

Nitroprnsside(sodium)-ferrieyanide (FGNP reagent) for aliphatic nitrogen compounds, e. g., cyanamide, guanidine, urea and thiourea and their derivatives for creatine and creatinine. 

Nitropmsside(sodiiim)-hydrogeii peroxide for guanidine, urea, thiourea and their derivatives, for creatme and creatinine. 

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