abstract |
Adducts are obtained by reacting carbonyl compounds of the formula I n nwhere R 1 and R 2 are as defined, with cyclic compounds of the formula IIn n nwhere X is selected from oxygen, sulfur and N—R 8 , R 3 -R 8 are as defined, and n is an integer from 1 to 4, which adducts are useful as tanning agents and preservatives. |