Patent ID: 6777559
Filing Date: 2004-08-17
Classification: C07D

Abstract:
A process preparing a compound of the formula: whereinR1 and R2 are independently selected from the group consisting of hydrogen and lower-alkyl; or R1 and R2 together with the ring carbon atoms to which they are attached form a monovalent carbocyclic or a monovalent carbocyclic aromatic ring or a monovalent carbocyclic or monovalent carbocyclic aromatic ring may substituted by halogen, lower-alkyl or lower-alkoxy; X is Nâ€”Z; Z is an amino protecting group selected from the group consisting of SO2Ra, NMe2, CO2Rb and CON(Rc)2; Ra is lower-alkyl or aryl; and Rb and Rc are lower-alkyl; which comprises: (a) cyclocarbonylating a compound of formula: wherein R3 is lower-alkyl, aryl or aralkyl, and R1, R2 and X are as defined above; to form a compound of formula: wherein R4 is lower-alkyl or aryl and R1, R2 and X are as defined above; and (b) saponifying the compound of formula (III) to produce the compound of formula (I).