| 摘要 |
The invention is concerned with a process for making a compound of formula wherein R1is hydrogen, alkyl, cyclo-alkyl, alkenyl, aryl or an amino protecting group; and R2, R3 each independently is hydrogen, alkyl, cyclo-alkyl, alkenyl or aryl; by reacting a compound of the formula wherein X is a protected hydroxy group; with R1NH2 to form a compound of formula wherein X and R1 are described herein above; and then reacting the compound of formula III with R2R3NH under pressure to form the compound of formula I. These compounds are valuable intermediates useful in making cephalosporin derivatives. |
