| abstract |
A process is provided for the synthesis of 4,5-diamino cyclohexene carboxylate ester (1): or a pharmaceutically acceptable salt thereof. R1 - R3 are a silyl-, an aliphatic, alicyclic, aromatic, arylaliphatic, or an arylalicyclic group. R4, R11 and R12 are H, a silyl-group, an aliphatic, alicyclic, aromatic, arylaliphatic, or an arylalicyclic group. 3,4-Dihydropyran compound (9): with R5 and R6 being suitable protecting groups, is reacted to form aldehyde (4): which is oxidized and converted to N-substituted carbamate (3): with R7 being a suitable protecting group. (3) is, via oxazolinidone (13): converted to azido carboxylate ester (2): and then to 4,5-diamino cyclohexene carboxylate ester (1). |