Tarek A. Zeidan

An unprecedented case of dodecamorphism: the twelfth polymorph of aripiprazole formed by seeding with its active metabolite

A new polymorph of aripiprazole has been discovered, making it the most polymorphic drug to date with twelve reported anhydrous forms, and a record-breaking ninth solved crystal structure. The new form was induced by seeding with crystals of the active metabolite dehydro-aripiprazole.

Novel N-5-(acyloxyalkoxy)carbonyl prodrugs of olanzapine with physicochemical properties for extended-release

An unexpected regioisomer was observed during the synthesis of olanzapine prodrugs. N-5-(acyloxyalkoxy)carbonyl-functionalized olanzapine derivatives were found to have favorable physicochemical properties, such as crystallinity, melting points, solubility and plasma conversion profiles suitable for formulation as extended-release injections.