Derivatives of C-076, a series of macrolides are described, in which the substituents are hydrocarbon groups. The hydrocarbon groups generally are alkyl groups which may be straight or branched and may optionally be substituted with phenyl. The substituted C-076 compounds are prepared by various procedures depending upon the position of the reaction site, and the particular C-076 compound being substituted. The compounds have profound anthelmintic, insecticidal, ectoparasiticidal and acaracidal activity and compositions for such uses are also disclosed.