Bierman, Muserlian and Lucas
(3,4,7,8,9,10-hexahydro-6,10-dioxo-6H pyridazino[1,2-A] [1,2] diazepine-1-carboxylic acid derivatives
 A compound of the formula ##STR1## wherein R is alkyl or aralkyl of up to 18 carbon atoms, the amine function being optionally protected are used to prepare compounds of the formula ##STR2## in which R retains its previous meaning and the amine is optionally protected. 
Aventis Pharma S.A.
C
C07K
inventional
Patrick Francis Veronique
Roussel Brion Croco