Dinitrophenylamino, dansyl. and biotin groups have been covalently attached to several azadirachtin derivatives via a linker group to give fluorescent or immunogenic compounds that generally retain the biological properties of azadirachtin. These compounds ate potential tools for the determination of the mechanisms of azadirachtin's action in living systems.
Azadirachtin ( ) is a natural product whose remarkable insecticidal and other biological properties have received increasing attention in recent years. 2-4 Azadirachtin's structure features a Azadirachtin (1) densely packed array of oxygen functionalities of many different types, making its total synthesis a true challenge that has yet to be achieved. 2 The complex chemistry of azadirachtin has made it difficult to determine which portions of the molecule am responsible for its many biological effects,3 including its recently discovered anti-malarial properties. 4 Furthermore, only the most cursory information about how azadirachtin exerts its effects in living systems is currently available.3 If any further progress is to be made in understanding the biological mode of action of azadiichtin, the proteins or other cellular entities with which it interacts will have to be elucidated. In pursuit of this goal, we have undertaken the synthesis of a number of derivatives of azadirachtin that contain immunogenic or fluorescent reporter groups.5 These derivatives generally retain the biological activity of azadirachtin, and the reporter ' groups which are attached to them provide a means of identifying azadirachtin-biological molecule