7'-amino-naphthazarin antibiotic derivatives

Naphthazarin antibiotic derivatives having general formula I ##STR7## and the pharmaceutically acceptable addition salts thereof, wherein:

• R represents hydrogen or hydroxy;
• R.sup.1 represents hydrogen or an -alk-X group wherein alk represents a (C.sub.1 -C.sub.4) alkylene and
• X represents hydrogen, hydroxy, cyano, trifluoromethyl, or a --NR.sup.2 R.sup.3 group wherein R.sup.2 and R.sup.3 independently represent hydrogen, (C.sub.1 -C.sub.4)alkyl or an amino-protecting group selected from (C.sub.1 -C.sub.5)alkoxycarbonyl, (C.sub.2 -C.sub.4)alkenyloxycarbonyl, cinnamyloxycarbonyl, benzyloxycarbonyl, p-nitro-benzyloxycarbonyl, 3,4-dimethoxy-6-nitrobenzyloxycarbonyl, 2,4-dichloro-benzyloxycarbonyl, 5-benzylisoxazolyl-methoxycarbonyl, 9-anthranylmethoxycarbonyl, diphenylmethoxycarbonyl, isonicotinyloxycarbonyl and S-benzyloxycarbonyl.