IMPROVEMENTS IN OR RELATING TO SPIROCYCLIC COMPOUNDS

The present invention relates to a compound of formula I, I wherein A is straight chain alkylene of 2 to 4 carbon atoms, or straight chain alkenylene of 2 to 4 carbon atoms, n is 1, 2 or 3, R is hydrogen or halogen of atomic number from 9 to 35, and either (i) R1 is a group of formula II, II wherein R2 and R3, independently, are hydrogen or alkyl of 1 to 4 carbon atoms, and R4 is alkyl of 1 to 4 carbon atoms, alkoxyalkyl of 2 to 5 carbon atoms, alkylthioalkyl of 2 to 5 carbon atoms, phenylalkyl or phenoxyalkyl or phenylthioalkyl, wherein the alkyl moiety has from 1 to 3 carbon atoms, or phenyl, the phenyl ring of each of the last four radicals being unsubstituted or mono-substituted by, or disubstituted independently by, alkyl of 1 to 4 carbon atoms, alkoxy of 1 to 4 carbon atoms, hydroxy or halogen of atomic number from 9 to 35, and R5 is hydrogen, or (ii) R1 and R5 together with the nitrogen atom to which they are bound are (a) 2,2,6,6-tetramethylpiperidinyl, (b) 2,2,5,5-tetramethylpyrrolidinyl, or (c) piperazinyl substituted in the 4 position by alkyl of 1 to 4 carbon atoms or phenyl which is unsubstituted, or mono-substituted by, or di-or tri-substituted independently by, alkyl of 1 to 4 carbon atoms, alkoxy of 1 to 4 carbon atoms, or halogen of atomic number from 9 to 35, useful as anti-hypertensives.