Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027960 (mole)
 21,279 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Primaquine (P) has long been used as an antimalarial drug. The following formulas are derived for determination of the ionization constants of PH3+3 by pH-titration method: Ka1 = [aH + (3 - a)Cp]/[(a - 2)Cp/aH - 1] Ka3 = [(1 - a)Cp aH - Kw]/(a Cp + Kw/aH) = (1/Ka2)[(2 - a)Cp a2H - Kw aH]/(Kw/aH + a Cp) + [(1 - a) Cp aH - Kw]/(Kw/aH + a Cp) in which Kw is the ionic product of water, a is the mole ratio of HClO4 to primaquine and Cp is the total concentration of primaquine. The ionization constants of primaquine in 50% (v/v) ethanol in water determined at 25 degrees C in the ionic strength range of 5 x 10(-3)-5 x 10(-2) mol/L are: Ka1 = (3.84 +/- 2.35) x 10(-2) (attributed to the secondary ammonium group of primaquine); Ka2 = (1.50 +/- 1.17) x 10(-8) (attributed to the tertiary ammonium group); Ka3 = (2.07 +/- 0.27) x 10(-10) (attributed to the primary ammonium group). The coordination ratio of primaquine to vitamin C in the above solvent is determined by continuous variation and mole ratio methods based on pH and conductance measurements to be 1:1, indicating that the coordination compound formed in the solution is mainly a 1:1 compound.
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PMID:[Determination of ionization constants of primaquine and study of its coordination ratio with vitamin C]. 180 12