Abstract: A compound of formula (I) or a pharmaceutically acceptable salt thereof, ##STR1## in which, R.sub.1 is hydrogen or lower alkyl;R.sub.2 is hydrogen or lower alkyl;R.sub.4 and R.sub.4 ' together form a group .dbd.N--Ra, or .dbd.CRaRb, where Ra is hydrogen, lower alkyl, aryl, aryloxy, lower alkylcarbonyl, arylcarbonyl, aryloxycarbonyl, lower alkoxy, lower alkoxy carbonyl, lower alkoxy carbonyl alkoxy, lower thioalkoxy, hydroxy, nitrile, heterocyclyl, or --NRcRd, where Rc is hydrogen, lower alkyl, cycloalkyl, aryl, aralkyl, lower alkylcarbonyl, arylcarbonyl, aminocarbonyl, aminothiocarbonyl, aminoiminocarbonyl, lower alkoxycarbonyl, lower alkoxythiocarbonyl, aryloxycarbonyl, thiocarbonyl, nitrile, carboxyl, heterocyclyl or heterocyclylcarbonyl, and Rd is hydrogen or lower alkyl; Rb is hydrogen, lower alkyl, aryl, lower alkylcarbonyl, lower alkoxycarbonyl, nitrile or nitro;or R.sub.4 is --NH--Ra, in which Ra is as defined above, and R.sub.4 ' is hydrogen or lower alkyl;each of R.sub.3 and R.sub.

Abstract: A compound of formula (I), or a pharmaceutically acceptable salt thereof, ##STR1## in which, R.sub.1 is hydrogen, lower alkyl or CH.sub.2 OR.sub.6 ;R.sub.2 is hydrogen or lower alkyl;R.sub.3 is hydrogen or lower alkyl;each of W and Z, which are different, represents --CR.sub.4 R.sub.5 -- or --(CR.sub.x R.sub.y).sub.n --, in which,R.sub.4 is hydrogen, C.sub.1-3 alkyl, C.sub.1-3 alkylthio or C.sub.1-3 alkoxy;R.sub.5 is C.sub.1-3 alkyl, C.sub.1-3 alkylthio or C.sub.1-3 alkoxy; or together R.sub.4 and R.sub.5 form a 3 to 6 membered carbocyclic ring, or a heterocyclic ring containing one or two ring oxygen, nitrogen or sulphur atoms;or R.sub.4 and R.sub.5 together form an oxo or methylene group;each of R.sub.x and R.sub.y is hydrogen or C.sub.1-3 alkyl; n is zero or 1;R.sub.6 is hydrogen, lower alkyl, lower alkylcarbonyl, arylcarbonyl, aralkylcarbonyl, heteroarylcarbonyl, optionally substituted aminocarbonyl, lower alkoxycarbonyl and aryloxycarbonyl;R.sub.

Abstract: A pharmaceutical composition comprising a compound of formula (I) or a pharmaceutically acceptable salt thereof: ##STR1## wherein: R.sub.1 is hydrogen, C.sub.1-6 alkyl, C.sub.1-6 alkoxy or halogen;R.sub.2 and R.sub.3 are both hydrogen or together represent a bond;R.sub.4 is hydrogen and R.sub.5 is hydrogen or R.sub.4 and R.sub.5 together represent an oxo group;R.sub.6 is hydrogen; C.sub.1-6 alkyl; C.sub.3-7 cycloalkyl; C.sub.3-7 cycloalkyl-C.sub.1-4 alkyl; phenyl or phenyl C.sub.1-7 alkyl in which the phenyl moiety is optionally substituted by one or two of halogen, ortho-nitro, meta-or para-methoxy, methyl or NR.sub.8 R.sub.9 wherein R.sub.8 and R.sub.9 are independently hydrogen or C.sub.1-6 alkyl or R.sub.8 and R.sub.9 together are C.sub.2-6 polymethylen, or 3,4-disubstituted by methylenedioxy or ethylenedioxy; or monocyclic heteroaryl-C.sub.1-4 alkyl or aliphatic heterocyclyl-C.sub.

Abstract: A compound of formula (I) or a pharmaceutically acceptable salt thereof: ##STR1## wherein: R.sub.1 is hydrogen, C.sub.1-6 alkyl, C.sub.1-6 alkoxy or halogen;R.sub.2 and R.sub.3 are both hydrogen or together represent a bond;R.sub.4 is hydrogen and R.sub.5 is hydrogen or R.sub.4 and R.sub.5 together represent an oxo group;R.sub.6 is phenyl, phenyl C.sub.1-7 alkyl or phenyl C.sub.1 -7 alkanoyl, in which the phenyl moiety is substituted by NR.sub.8 R.sub.9 wherein R.sub.8 is C.sub.1-6 alkyl substituted by a group R.sub.10 selected from hydroxy, halo, CF.sub.3 or COR.sub.11 where R.sub.11 is hydroxy, C.sub.1-4 alkoxy or amino optionally substituted by one or two C.sub.1-4 alkyl groups, and R.sub.9 is hydrogen, C.sub.1-6 alkyl or R.sub.8 ; andR.sub.7 is hydrogen or C.sub.1-4 alkyl.

Abstract: 1-(3,4-Dialkoxybenzyl)-6,7-dialkoxyl-1,2,3,4-tetrahydro- and 3,4-dihydroisoquinolines wherein the alkoxy groups in the benzyl ring are different from those in the isoquinoline nucleus and one contains from 2 to 6 carbon atoms while the other contains from 3 to 6 carbon atoms are useful in the treatment of peripheral vascular disease. A typical embodiment is 1-(3,4-diethexybenzyl)-6,7-diisopropoxy-3,4-dihydroisoquinoline hydrochloride.