A compound of the formula ##STR1## wherein R.sub.1 is hydrogen, --COOR.sub.11 or ##STR2## R.sub.11 is optionally substituted lower alkyl, R.sub.12 is optionally substituted hydrocarbon, heterocyclic or heterocyclic-lower alkyl, R.sub.13 is hydrogen or lower alkyl, or R.sub.12 and R.sub.13 together constitute a heterocyclic ring together with the attached nitrogen atom, and R.sub.2 is hydrogen or hydroxyl, or a pharmaceutically-acceptable salt thereof, has stronger antibacterial activity against Gram-positive bacteria than does tylosin. It is produced by deformylation, or by oxidizing a formyl at position-14, or by amidating the latter compound.