RT Journal Article
SR Electronic
T1 Stability of Vidarabine-5′-Phosphate in Aqueous Solutions
JF PDA Journal of Pharmaceutical Science and Technology
JO PDA J Pharm Sci Technol
FD Parenteral Drug Association (PDA)
SP 60
OP 64
VO 38
IS 2
A1 Hong, Wen-Hal
A1 Szulczewski, Dale H.
YR 1984
UL http://journal.pda.org/content/38/2/60.abstract
AB The hydrolysis kinetics of a new antiviral agent, vidarabine-5'-phosphate, was studied spec-trophotometrically at pH 4-10, μ = 0.5, at 99 °C. Vidarabine-5′-phosphate hydrolyses via water attack on the protonated, neutral, and mono-ionized species. The hydrolysis rates follow pseudo first-order kinetics. The pH-rate profile suggests that vidarabine-5′ phosphate attains its optimal stability in the pH region 9-9.5. The stability of vidarabine-5′ -phosphate at pH 6.85 was studied at 61°, 80°, and 99 °C. The Arrhenius activation energy found was 29.4 Kcal/mole, and the time required for 10% loss, to 9, was estimated from the Arrhenius plot (12.4 years at 25 °C).