The present invention discloses compounds of formulae I, II, III or IV or pharmaceutically acceptable salts, esters, or prodrugs thereof: ##STR1##

which exhibit antibacterial properties. The present invention further relates to pharmaceutical compositions comprising the aforementioned compounds for administration to a subject in need of antibiotic treatment. The invention also relates to methods of treating a bacterial infection in a subject by administering a pharmaceutical composition comprising the compounds of the present invention. The invention further includes process by which to make the compounds of the present invention.