NEW SYNTHESES OF 2,4-DIAMINOPYRROLES AND AMINOPYRROLINONES

Oxazolin-2-ylidene-malononitriles 3a-d, obtainable from thioketenamina ls and alpha-halogen-ketones, react with primary and secondary amines to afford 2,4-diamino-pyrroles 5a-h. Mercaptobenzen as nucleophilic ag ent gives the 4-amino-2-phenylthio-pyrrole 5j. Analogously, cyano-(3,5 -diphenyl-3H-oxazol-2-ylidene)-acetic acid methyl esters were prepared as intermediates for the synthesis of 2-amino-4-oxo-pyrrolines 10a-d. The isomeric 4-amino-2-oxo-pyrrolines 13a-d can be obtained from 4-am ino-2-methoxy-pyrroles, which serves as proof for the position of subs tituents. The structures were investigated by H-1 and C-13 NMR spectro scopy.