Pharmacologically active catechol derivatives of formula I ##STR1## wherein R.sub.1 and R.sub.2 independently comprise hydrogen, alkyl, acyl, optionally substituted aroyl, lower alkylsulfonyl or alkylcabamoyl or taken together form a lower alkylidene or cycloalkylidene, X comprises an electronegative substituent such as halogen, nitro, cyano, lower alkylsulfonyl, sulfonamido, aldehyde, caboxyl or trifluoromethyl and R.sub.3 comprises hydrogen, halogen, hydroxy alkyl, amino, nitro, cyano, trifluoromethyl, lower alkylsulfonyl, sulfonamide, aldehyde, alkyl carbonyl, aralkylidene carbonyl or carboxyl or a group selected from ##STR2## wherein R.sub.4 comprises hydrogen, alkyl, cyano, carboxyl or acyl and R.sub.5 comprises hydrogen, cyano, carboxyl, alkoxycarbonyl, carboxyalkenyl, nitro, acyl, optionally substituted aroyl or heteroaroyl, hydroxyalkyl or carboxyalkyl or R.sub.4 and R.sub.5 together form a five to seven membered substituted cycloalkanone ring;--(CO).sub.n (CH.sub.2).sub.m --CORwherein n is 0-1 and m is 0-7 and R comprises hydroxy, alkyl, carboxyalkyl, optionally substituted alkene, alkoxy or optionally substituted amino; ##STR3## wherein R.sub.8 and R.sub.9 independently comprise hydrogen or one of the following optionally substituted groups; alkyl, alkenyl, alkynyl, cycloalkyl, aralkyl, or together form an optionally substituted piperidyl group;--NH--CO--R.sub.10wherein R.sub.10 comprises a substituted alkyl group.