Synthesis of novel fluorescent acridono- and thioacridono-18-crown-6 ligands

Novel fluorescent 18-crown-6 type ligands containing acridono and thioacrid ono units were synthesised. The acridono ligand was prepared by the oxidati on of its acridino analogue, and also by the cyclisation of 4,5-dihydroxyac ridine-9(10H)-one and tetraethylene glycol di-p-tosylate in the presence of K2CO3. The acridono macrocycle was converted to the thioacridono ligand us ing Lawessons's Reagent. The synthesis of several precursors leading to the preparation of an acridono-18-crown-6 fluorophore was also performed. Thes e precursors can also be very useful building blocks for acridine, acridone and thioacridone derivatives of chemotherapeutical importance. (C) 2001 El sevier Science Ltd. All rights reserved.