MAJID CHERAGHALI A, MORIN K W, KUMAR R, KNAUS E E, WIEBE L I. BILIARY EXCRETION AND BLOOD/PLASMA RATIO OF NOVEL 5-BROMO-6-ALKOXY-5,6-DIHYDRO PRODRUGS OF 5-ETHYL-2'-DEOXYVRIDINE. Med J Islam Repub Iran 1998; 11 (4) :355-361
URL:
http://mjiri.iums.ac.ir/article-1-1081-en.html
From the Department of Pharmacology, Faculty of Medicine, Baghiatoliah Medical Sciences University, Tehran, Iran
Abstract: (4034 Views)
The biliary excretion and blood/plasma ratios of four novel 5-bromo-6-alkoxy-
5,6-dihydro prodrugs to S-ethyl-2'-deoxyuridine (EDU) including (-)-trans-(5S,
6S)-S-bromo-S-ethyl-6-methoxy-S, 6-dihydro-2'-deoxyuridine (BMEDU), (+ )-trans(
SR, 6R)-S-bromo-S-ethyl-6-ethoxy-S, 6-deoxyuridine (BEEDU), (+ )-trans-(SR,
6R)-5-bromo-5-ethyl-6-ethoxy -S, 6-dihydro-S '-O-valeryl-2 ':.deoxyuridine
(VBEEDU) and (+)-trans-(SR, 6R)-S-bromo-S-ethyl-6-ethoxy-S, 6-dihydro-5, 6-
dihydro-3', S'-di-O-valeryl-2'-deoxyuridine (DVBEEDU) were determined using
[4-14C]-labelled compounds. Liver samples taken following iv injection of 126 kBq
(3.4IlCi) of these [4-14C]-labelled S,6-dihydro prodrugs into the tail vein of male
Balb-C mice showed a higher percentage of the injected radioactivity than blood
samples. A substantial amount of radioactivity was present in the large intestine,
small intestine and gallbladder. Intestinal samples collected at longer post injection
times showed a higher percentage of the injected dose relative to earlier post injection
times. Bile samples collected at 8 min post injection of [4-14C]-labelled BMEDU,
BEEDU, VBEEDU and DVBEEDU contained the highest radioactivity levels.
Excretion of radioactivity in rat bile following a jugular vein injection showed a
biexponential decline, but the radioactivity excretion rates in bile for all four
compounds investigated were quantitatively similar. Accumulation of radioactivity
in rat bile samples collected after injection of [4_14C]-BEEDU was substantially
higher than that for [4_14C]-BMEDU, [4_14C]_VBEEDU and [4_14C]-DVBEEDU.
The distribution of radioactivity in rat whole blood and plasma samples taken at the
same post injection times were substantially different. It was postulated that the rate
of conversion of the S, 6-dihydro prodrug to EDU is the main determinant of the
whole blood/plasma ratio.