Abstract A series of perhydro heterocycles of eight to ten ring members containing one nitrogen and two oxygen atoms has been prepared. These include four 1, 3, 6-dioxazocines, and 1, 3, 7-dioxazonine and one 1, 3, 8-dioxazecine. A twelve-membered ring containing two oxygen and two nitrogen atoms was also prepared. An X-ray structure of one of the 1, 3, 6-dioxazocines, 5, was determined. This compound crystallized in the orthorhomic space ...