The invention relates to antibacterial compounds of formula I
wherein R
1
is H or halogen; R
2
is alkynyloxy or the group M; R
3
is H or halogen; M is one of the groups
wherein A is a bond, CH
2
CH
2
, CH═CH or C≡C and R
1A
, R
2A
, R
3A
, R
1B
and R
1C
are as defined in claim
1;
and salts thereof.