Solvolysis study of cycliciminomitomycins

The solvolysis rates for the substituted C(7)-cyclohexylamino- or C(8)-cyclohexyliminomitomycins 8-19 were determined in buffered methanolic solutions (0.06 M bis-Tris.HCl, pH: 5.5) at 25 degrees C and then compared with mitomycin C (1) and porfiromycin. Kinetic studies showed that C(8)-cyclohexyliminomitomycins 8-13 underwent solvolysis 150-230 times faster than mitomycin C (1) to give C(1)-methoxymitosene products. The solvolysis rates were slightly faster than that reported for 6. The C(7)-(2'-hydroxy)cyclohexylaminomitomycins 16-19 exhibited comparable solvolysis rates with 1 and porfiromycin.