A radioimmunoassay combined with solid-phase extraction for the determination (pg ml-1) of AR-C15849XX) in human plasma.
A radioimmunoassay has been developed for the determination of AR-C15849KF, a CCK-8 analogue, in human plasma. The method incorporates solid-phase sample extraction, is suitable for the determination of the analyte at pg ml-1 concentrations and is based on a method developed and validated for dog plasma. The solid-phase extraction, using ion-exchange aminopropyl and octadecyl sorbents sequentially, was retained for this procedure to remove matrix interferences in the plasma and to enhance method sensitivity. The calibration range is 10-500 pg ml-1, using a 1 ml sample of undiluted human plasma. The method has been successfully used to generate early human pharmacokinetic data during a programme of exploratory development.
A radioimmunoassay combined with solid-phase extraction for the determination of a novel anti-obesity agent, ARL 15849XX, in dog plasma.
A radioimmunoassay has been developed for the determination of ARL 15849XX, a cholecystokinin-8 (CCK-8) analogue, in dog plasma. The method incorporates solid-phase sample extraction and is suitable for the determination of the analyte at picogram per millilitre concentrations. The antiserum was raised in Suffolk-cross sheep following primary and booster immunisations with an immunogen prepared by conjugating ARL 16935XX, an analogue of ARL 15849KF, to bovine serum albumin. The radioligand was prepared by the no-carrier-added 125I iodination of a non-sulphated derivative, ARL 15745XX. The solid-phase extraction procedure, carried out using ion-exchange aminopropyl and octadecyl sorbents sequentially, was introduced to remove matrix interferences in the plasma and to enhance the method sensitivity. The calibration range is 20-1000 pg ml-1, using a 1 ml sample of undiluted dog plasma.
Synthesis of 2,4-dideoxy-.beta.-D-erythro-hexopyranosyl nucleosides
The synthesis of 1-(2,4-dideoxy-β-D-erythro-hexopyranosyl)thymine (12) 1 was accomplished using two different synthetic routes. It was obtained starting either from 1,2:5,6-di-O-isopropylidene-α-D-glucofuranose or from tri-O-acetyl-D-glucal. The other modified nucleosides, with either a cytosine, guanine, or adenine moiety, were synthesized using the second reaction scheme. Deoxygenation reactions were accomplished with the (2,4-dichlorophenoxy)thiocarbonyl derivatives generated in situ