Abstract: A combinatorial library is disclosed which is represented by Formula ##STR1## wherein: ##STR2## is a solid support; T'-L- is an identifier residue; and -L'-II' is a ligand/linker residue. This library contains hydroxypropylamines of the formula:Aa.sup.1 -Aa.sup.2 -(CH.sub.2 Ar.sup.1)-CH.sub.2 CHOH-CH.sub.2 XR.sup.1IIwherein:Aa.sup.1 and Aa.sup.2 is each an amino acid joined to each other through an amide bond;Ar.sup.1 is an aromatic ring system;--CH.sub.2 Ar.sup.1 is attached to N on Aa.sup.2 ; andR.sup.1 is H, C.sub.1-20 alkyl, alkenyl, alkynyl, aryl, heteroaryl, aryl or heteroaryl fused to a 3- or 4-membered moiety to form a non-aromatic second ring, or substituted C.sub.1-20 alkyl, alkenyl, or alkynyl.

Abstract: There are disclosed novel avermectin .DELTA. 23,24-derivatives (also referred to as 23,24-dehydro compounds). The compounds are prepared by selective dehydration of avermectin A2 or B2 compounds. The avermectin compounds have utility as anti-parasitic agents and compositions for that use are also disclosed. The compounds are also highly potent insecticides against agricultural pests. The .DELTA. 23,24-avermectin compounds have increased activity relative to the A2 or B2 compounds.

Abstract: There are disclosed novel avermectin and milbemycin compounds wherein the 8a position is oxidized to a ketone group. The 8a-oxo compounds are prepared by oxidizing an avermectin or milbemycin compound. The avermectin and milbemycin 8a-oxo compounds have utility as anti-parasitic agents and compositions for that use are also disclosed. The compounds are also highly potent insecticides against agricultural pests.