New derivatives of erythromycin, their process for the preparation and their use as medicines

The invention relates to the compounds of formula (I) (CF DRAWING IN BOPI) wherein R1 is a hydroxyl or O-acyl radical containing from 2 to 20 carbon atoms, R2 is hydrogen or methyl, R3 is : either a radical - (CH2) m R4 wherein m is an integer varying from 1 to 6, or a radical (CF DRAWING iN BOPI) wherein n and p identical or different represent an integer ranging from 0 to 6, and or a and B identical or different represent an atom hydrogen or a halogen atom or an alkyl radical containing up to 8 carbon atoms, the geometry of the double bond being E or Z or an E + Z mixture, or a and B form with the carbon atoms to which they are attached form a triple bond, or a radical -N (CH 2) q R 4 wherein q is an integer ranging from 0 to 6, R4 is a heterocyclic radical optionally substituted mono- or polycyclic as well as their addition salts with acids. the compounds of example 1 have useful antibiotic properties.