title: Reaction of 1-n-propyl-1-nitrosourea with DNA in vitro.
abstract: [n-propyl-2,3-3H]1-n-Propyl-1-nitrosourea (PNU) (sp. act.: 665 mCi/mmol) was synthesized and incubated with calf thymus DNA at pH 7.0 and 37 degrees C in vitro. The degree of alkylation was proportional to the concentration of PNU added. The extent was 68 pmol/mg of DNA at 1 mM PNU. After mild acid hydrolysis, purine bases were separated by Sephadex G-10 column chromatography. Although O6-n-propylguanine and O6-iso-propylguanine were separated by this method, 7-n-propylguanine and 7-iso-propylguanine were not separated. Then we used a h.p.l.c. equipped with a mu Bondapak-C18 reverse phase column with a linear gradient elution. 7-n-Propylguanine and O6-n-propylguanine were identified as major reaction products, and 7-iso-propylguanine and O6-iso-propylguanine were identified as minor reaction products. The ratio of O6-n- and iso-propylguanine/7-n- and iso-propylguanines was 0.73. This ratio is similar to that produced by 1-ethyl-1-nitrosourea and 1-n-butyl-1-nitrosourea.
mesh_terms: D000818:Animals; D002273:Carcinogens; D002417:Cattle; D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D004247:DNA; D007700:Kinetics; D009607:Nitrosourea Compounds / Q000138:chemical synthesis; D013045:Species Specificity; D013950:Thymus Gland; D014316:Tritium
chemical_list: D002273:Carcinogens; D009607:Nitrosourea Compounds; D014316:Tritium; C020796:propylnitrosourea; D004247:DNA