| abstract |
According to the invention, the glycine amide of the formula is reacted with a dioxo n-derivative of the formula with a dioxo compound of the general formula wherein L is a leaving group such as iodine, bromine or alkyl or arylsulfonyloxy. under reflux conditions, the N-acetyl group of the dioxol is replaced by a dimethylacetate group and the carboxyl group is esterified to give (S) -2-amino-6,6-dimethoxycaproic acid methyl ester which double inhibitory [4S- [4a (R *), 7a, 10ab]] -octahydro-4 - [(2-mercapto-1-oxo-3-phenylpropyl) amino] -5-oxo-7H- The pyrido [2,1-b] [1,3] -thiazepine-7-carboxylic acid intermediate is a stable intermediate of the (S) -2-amino-6,6-dimethoxycaproic acid methyl ester. and its salts, oh |