SUPPRESSION OF THE CONVERSION OF 3-<i>t</i>-BUTYL-1-METHYL-1-NITROSOTHIOUREA TO 3-<i>t</i>-BUTYL-1-METHYLUREA BY β-CYCLODEXTRIN UNDER ACIDIC CONDITIONS
作者:Masayoshi Isobe
DOI:10.1246/cl.1985.65
日期:1985.1.5
The denitrosation of 3-t-butyl-1-methyl-1-nitrosothiourea(1) was retarded by β-, and γ-cyclodextrins(CDs) at pH 4.70. Decomposition of 1 in the presence of β-CD produced selectively 3-t-butyl-1-methylthiourea(1a), which was remarkably different from the product ratio in the absence of β-CD. These results may be caused by both the protective and the microsolvent effect of β-CD.
Electronic and Steric Effects of Alkyl Group on Denitrosation of 3-Alkyl-1-methyl-1-nitrosothioureas
作者:Masayoshi Isobe
DOI:10.1246/bcsj.58.2844
日期:1985.10
According to rate measurements in CH3COOD–D2O, the kinetic isotope effect kH:kD is 1.25 for 4. Except 3, a linear plot of logkR⁄kMe for the denitrosation of RNHCSN(NO)CH3 vs. σ* provides ρ*=−0.98 (r=−0.997). The significant factor affecting the rate-determining step of the denitrosation of these N-nitrosothioureas at pH 4.6 is the electroniceffect of the substituent at the N3 position.