著者

福井 美園 滝谷 玲子 多田 敬三

出版者

慶應義塾大学

雑誌

共立薬科大学研究年報 (ISSN:04529731)

巻号頁・発行日

no.25, pp.p49-59, 1981-03

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The decomposition of 1-nitroso-1-butyl-3,3-dimethylurea (DM-NBU), which was found to have both leukomogenic and vaginatumorigenic activities on female rats, was studied in the buffer solutions of various pH values from 2 to 12 at 37℃. It was found that the decomposition velocity of DM-NBU was lowest in the neutral medium and increased as pH values either increased or decreased from 7,and the velocity was generally much lower than that of 1-nitroso-1-butylurea (NBU). The effect of the concentration of DM-NBU on the velocity has not yet been examined in detail, but it has been found that lower concentrations resulted in more rapid decomposition than higher ones did in the range of pH examined only except at pH 10. The main decomposition products of DM-NBU were carbondioxide, dimethylamine, 1-butanol and 2-butanol. Although the above two isomers of butanol were also detected and determined in the case of NBU and their total amounts were almost equal at each pH values of 2,7 and 12,in the case of DM-NBU, they were almost equal in the range of pH values from 12 to 6 but they fell suddenly at pH 5 and, thereafter, gradually decreased as pH values decreased. The ratio of the amount of 1-butanol to that of 2-butanol was 1.8-2 in the range of pH tested. The determination of the residual amounts of DM-NBU was made absorption-spectrophotometrically and that of the butanols was carried out gaschromatographically after the decomposition proceeded completely.