METHOD OF OBTAINING NOVEL DERIVATIVES OF N-(4-PIPERIDINYL) (DIHYDROBENZOFURANE OR DIHYDRO-2H-BENZOPYRANE) CARBONAMIDES

Benzamide piperidinyl cpds. of formula (I) and their salts N-oxides and isomers are new. A = CH2-CH2-, -CH2-CH2-CH2- or -(CH2)4- where 1 or 2 H of these radicals may be replaced by 1-6C alkyl. R1 = H or halo. R2 = H, NH2, mono- or di(1-6C alkyl)amino or 1-6C alkylcarbonylamino. R3 = H or 1-6C alkyl. L = 3-6C cycloalkyl; 5-6C cycloalkanone, 3-6C alkenyl (opt. substd. with aryl), -Alk-R4, -Alk-X-R5, -Alk-Y-COOR7 or -Alk-Y-CONR9R10. Alk = 1-6C alkanediyl. R4 = H, CN, 1-6C alkylsulphonylamino, 3-6C cycloalkyl, 5-6C cycloalkanone, aryl, di(aryl)methyl or Het. R5 = H, 1-6Calkyl, hydroxy-1-6C alkyl, 3-6C cycloalkyl, aryl or Het. X = O, S, SO2 or NR6. R6 = H, 1-6C alkyl or aryl. R7 = H, 1-6C alkyl, 3-6C cycloalkyl, aryl aryl-(1-6C alkyl) di(aryl)methyl, 1-6C alkyloxy or OH. Y = NR8 or a direct bond. R8 = H, 1-6C alkyl or aryl. R9, R10 = independently H, 1-6C alkyl, 3-6C cycloalkyl, aryl or aryl-1-6C alkyl, or R9 and R10 together form an opt. substd. pyrrolidinyl piperidinyl, piperazinyl or 4-morpholinyl radical. Aryl = opt. substd. phenyl. Het = a five or six-membered heterocyclic with 1,2,3 or 4, of S, S or N. (I) are new when L = H. 3 cpds. are specifically claimed e.g. 5-amino-6-chloro-3,4-dihydro-N- (1-tetrahydro-2-furanyl)- methyl)-4-piperidinyl)-2H-1 -benzopyran-8-carboxamide.