Certain hetero phosphonic acid derivatives of 2-piperidine or 2-tetrahydropyridinecarboxylates and esters thereof which are useful for the treatment of disorders responsive to blockade of the NMDA receptor in mammals

Claim 1

A compound of the formula ##STR17## or a compound of formula II with a double bond present between the 3 and 4 or between the 4 and 5 carbon atoms of the piperidyl ring, so as to form a tetrahydropyridinyl ring in which the phosphono bearing chain is attached at the 3, 4, or 5-position of the piperidinyl or tetrahydropyridinyl ring, and wherein R and R' represent hydrogen, lower alkyl, benzyl, benzyl substituted on phenyl by halogen, lower alkyl or lower alkoxy, lower alkanoyloxymethyl, lower alkanoyloxymethyl substituted on oxymethyl by lower alkyl, cyclohexyl or cyclopentyl; R 2 represents hydrogen, lower alkyl, aryl-lower alkyl or lower alkanoyl; R 3 represents hydrogen, lower alkyl or aryl-lower alkyl; COR 1 represents carboxy or carboxy derivatized in the form of a pharmaceutically acceptable ester; A represents (CH.sub.2).sub.m -X-(CH.sub.2).sub.n (A) (CH 2 ) m being attached to the ring, wherein m represents zero, 1, 2 or 3; n represents 1, 2 or 3; X represents O, S, SO, SO 2 , CO-NR b , R b N-CO or N-Ra; Ra represents hydrogen, lower alkyl, aryl, aryl-lower alkyl or acyl; R b represents hydrogen, lower alkyl or aryl-lower alkyl; and wherein one or more of carbon atoms within A may be substituted by lower alkyl; acyl in the above definitions represents lower alkanoyl, lower alkoxycarbonyl, aryl-lower alkanoyl or aryl-lower alkoxycarbonyl; aryl in the above definitions represents phenyl or phenyl substituted by lower alkyl, lower alkoxy or halogen; and carboxy esterified in form of a pharmaceutically acceptable ester represents lower alkoxycarbonyl, (amino, mono- or di-lower alkylamino)-substituted straight chain C 2 -C 5 -lower alkoxycarbonyl, carboxy substituted lower alkoxycarbonyl, lower alkoxycarbonyl-substituted lower alkoxycarbonyl, benzyloxycarbonyl, pyridylmethoxycarbonyl, lower alkanoyloxy-substituted methoxycarbonyl, (lower alkanoyloxy or lower alkoxy)-substituted lower alkoxymethoxycarbonyl, bicyclo[2,2,1]heptyloxycarbonyl-substituted methoxycarbonyl, 3-phthalidoxycarbonyl, (lower alkyl, lower alkoxy, halo)-substituted 3-phthalidoxycarbonyl or lower alkoxycarbonyloxy-lower alkoxycarbonyl; or a pharmaceutically acceptable salt thereof.