Bis-pyridoxazole-stilbene derivatives for optical brightening
Abstract
Abstract A NOVEL CLASS OF HETEROCYCLIC STILBENE DERIVATIVES HAVE OUTSTANDING PROPERTIES AS OPTICAL BRIGHTENING AGENTS. THE NEW COMPOUNDS ARE BIS-PYRIDOXAZOLE-STILBENES OF THE FORMULA: 4,4''-BIS(A<(-N=C(-)-O-))STILBENE WHERE EACH A REPRESENTS A PYRIDO RING ATTACHED THROUGH TWO ADJACENT CARBON ATOMS THEREOF TO N AND O, REPECTIVELY, AND WHERE THE PYRIDO RINGS AND THE PHENYLENE RINGS MAY BE SUBSTITUTED. NEW INTERMEDIATES FOR THE PREPARATION OF THE BRIGHTENER COMPOUNDS ARE BIS-AMIDES OF THE FORMULA: 4,4''-BIS(PYRIDYL-NH-CO-)STILBENE WHEREIN EACH KPYRIDINE RING CARRIES A HALO OR A HYDROXYL RADICAL IN A POSITION ORTHO TO THE POINT OF ATTACHMENT OF THE -NH- BOND AND MAY BE FURTHER SUBSTITUTED AND WHEREIN THE PHENYLENE RINGS MAY ALSO BE SUBSTITUTED.
Inventors
- 👤 H Kaempfen
Bibliographic Details
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