Indole derivatives (I) are used to prepare medicaments for treating bacterial diseases. Indoles derivatives of formula (I) are used to prepare medicaments for treating bacterial diseases. R : H, 1-7C (halo)alkyl, 1-7C alkoxy, 7-11C arylmethyl, CH 2NAA', CH 2CH 2NAA', NAA', 6-10C arylsulfonyl, PG, OH, OA" or trialkylsilyl; A, A' : H or 1-4C alkyl; A" : 1-7C alkyl optionally substituted with aryl or NH 2; PG : t-butoxycarbonyl, fluorenylmethoxycarbonyl, benzyloxycarbonyl, trifluoroacetyl or benzoyl; R 3H or halo; R 4-R 7H, 1-4C alkyl, CF 3, OH, 1-7C alkoxy, CH 2OH, CH 2OA", OCF 3, halo or NAA'; R 1= H, 1-6C alkyl, 7-11C arylmethyl, (CH 2) mNH 2 (optionally protected), 6-10C aryl (optionally substituted with NO 2 or OMe), CH 2OH (optionally protected) or CH 2SH (optionally protected); R 2H, OH, O ->;, COCH 2ONH 2 (optionally protected), 1-10C acyl, 1-10C alkoxy, benzyloxy, 1-10C alkoxycarbonyl, benzyloxycarbonyl, OCONH 2 or OCSNH 2; B : N-CH(X)Ar, N +>;=C(X)Ar, N-PG' or N-A; Ar : phenyl substituted with 1-3 of H, OH, 1-4C alkoxy and NAA'; X : H, 1-4C alkyl, 6-10C aryl, alkoxymethyk, arylmethoxymethyl or trialkylsilyloxymethyl; PG' : t-butoxycarbonyl or benzyloxycarbonyl. Independent claims are also included for: (1) 3-(1,2-di(t-butoxycarbonylamino)ethyl-5-R 5'-6-R 6'-indoles; (2) 3-(1-(N-benzyl-N-hydroxyamino)ethyl)-6-bromoindole, 3-(1-(N-(4-methoxybenzyl)-N-hydroxyamino)ethyl)-5-bromoindole, 3-(1-(N-(4-methoxybenzyl)-N-hydroxyamino)-2-t-butoxycarbonylaminoethyl)-5-bromoindole, 3-(1-(N-t-butoxycarbonyl-N-hydroxyamino)-2-t-butoxycarbonylaminoethyl)-6-bromoindole, 3-(1-benzylaminoethyl)-5-bromoindole, 3-(1-(N-(4-methoxybenzylidene)-N-oxidoammonio)-2-t-butoxycarbonylaminoethyl)-5-bromoindole, 3-(1-hydroxyamino-2-t-butoxycarbonylaminoethyl)-5-bromoindole, 3-(1-hydroxyamino-2-t-butoxycarbonylaminoethyl)-6-bromoindole, 3-(1-amino-2-t-butoxycarbonylaminoethyl)-5-bromoindole, 3-(1-amino-2-t-butoxycarbonylaminoethyl)-6-bromoindole, 3-(1,2-diaminoethyl)-6-bromoindole dihydro