PROCESS OF PREPARATION OF BY-PRODUCTS OF 1-OXA-2-OXO-3,8-DIAZO-SPIRO-4,5-DECANE

摘要

PT--81638 A 1-Oxa 2-oxo 3,8-diaza spiro (4,5) decane derivs. of formula (I) are made by (a) reduction of 4-hydroxy 4-hydroxyaminomethyl piperidines by catalytic hydrogenation; (b) treating with phosgene to obtain 1-oxa 2-oxo 3-hydroxy 3,8-diaza spiro-4,5)-decane; and (c) catalytic hydrogenation of the hydroxamic acids to give the derivs of formula (I)