HPLC MEASUREMENT OF THE NOVEL NONNUCLEOSIDE ANTI-HIV AGENT, (-A()DIHYDROCALANOLIDE)

An HPLC assay was established to determine levels of the promising ant i-HIV agent (+)dihydrocalanolide A (DHCal-A; NSC 678323) in murine pla sma. The structurally related compound costatolide (NSC 661122) was fo und to be a suitable internal standard. Drugs were extracted from plas ma using a solid phase Cls cartridge. After injection onto an ODS anal ytical HPLC column, compounds were eluted using an acetonitrile: water mobile phase. Drugs were quantified over the assay range of 19.5 to 6 25 ng/mL with excellent within- and between-day reproducibility. Resul ts are obtained from the application of the described method to determ ination of dihydrocalanolide A pharmacokinetics in mice. This is the f irst report of a validated HPLC assay for determining dihydrocalanolid e A levels in biological fluids such as mouse plasma.