METABOLISM OF PURINE NUCLEOSIDE ANALOGS.

摘要: Summary A study was made of the cleavage ribosides and 2′-deoxyribosides thioguanine, adenine, 6-mercaptopurine in mouse tissues. Evidence indicated that this a phosphorylytic cleavage. Changes sugar moiety from ribose or 2′-deoxyribose to xylose, arabinose, 3′-deoxyribose, 5′-deoxyallose 6′-deoxyallose prevented shift ribosidic linkage position 9 7 purine cleavage, as did esterification with acetyl propyl groups. The nucleoside phosphorylase found be active on both α- β-anomers 2′-deoxythioguanosine 2′-deoxyribosyl-6-mercaptopurine. relative rates these anomers varied tissue source. adenosine deaminase tissues β-anomers, but not α-anomers. Various changes decreased abolished activity. Km9s were determined for ribosyl, arabinosyl xylosyl adenine. substrate affinity higher order ribosyl As result, it demonstrated adenine could used combination protect latter two analogs blood, so they able reach subcutaneous tumors via circulation produce some inhibitory effects otherwise possible.