| abstract |
Cyclic urea derivatives of Formula 1n n n a) reacting a urea derivative of formula 2 with a diketone of formula 3,n n n b) hydrogenation of the product from step a) in the presence of a metal-containing catalyst.n n n n n n n n n n n n n n n n n n n n n n n n In the above formulas, X, X ', Y, Y' and Z may have various meanings. |