The ornithine sulfonamide 1 was identified by random screening as weak
fibrinogen receptor antagonist. Homologation of the carboxylic acid f
unction and further structure activity studies led to the development
of novel beta-amino acid derivatives, which are potent and orally acti
ve antagonists of the platelet fibrinogen receptor GPIIb/IIIa. (C) 199
7 Elsevier Science Ltd.