Spiropiperidines. I. Synthesis of 1'-substituted spiro(4H-3,1-benzoxazine-4,4'-piperidin)-2(1H)-one derivatives and evaluation of their antihypertensive activity.

General synthetic methods for the preparation of 4-(2-aminophenyl)-4-hydroxypiperidine derivatives have been developed. The application use of these derivatives in the synthesis of 1'-substituted spiro [4H-3, 1-benzoxazine-4, 4'-piperidin]-2 (1H)-one derivatives is described, and the antihypertensive activity of the products is also reported.