INTERMEDIATE COMPOUNDS FOR THE PREPARATION OF MESO-SUBSTITUTED CYANINE, MEROCYANINE AND OXONOLE DYES

摘要

The present invention provides new intermediate compounds enabling the preparation of N-meso substituted cyanine, merocyanine or oxonole dyes wherein the N-meso substituent comprises electron withdrawing groups and wherein such N-meso substituents are introduced at the intermediate level. These intermediates enable the formation of dyes having in the meso-position N-substituents comprising electron withdrawing groups without the need for further derivatization of the meso-substituent at the dye level.