Heterocyclen als Bausteine neuer optischer Aufheller

Abstract

Optische Aufheller werden in Waschmitteln und Textilien sowie in Papier, Kunststoffen und Lacken angewendet. Die meisten optischen Aufheller enthalten Heterocyclen, z. B. Cumarine, 2‐Pyrazoline, Naphthalimide, Pyrazole, Triazole, Oxadiazole und Triazine. In diesem Aufsatz werden Synthesen, Eigenschaften und Anwendungsmöglichkeiten neuer optischer Aufheller anhand der Patentliteratur besprochen.

α,β-Unsaturated Fischer Carbene Complexes vs. 1,3-Dipoles: Reactions with Nitrones and Nitrilimines

“…Esters 14, 18, or 20 were isolated as fluorescent syrups. [32,20,21] Optical rotations of these compounds could not be determined due to the fluorescence, as the solutions were not permeable to sodium lamp irradiation. 10 H),2 H),4 H),3.52 (d,2 H,J ϭ 17.6 Hz),3.18 (d,1 H,J ϭ 17.6 Hz),3.16 (d,1 H,J ϭ 17.6 Hz),48 H).…”

“…[16] These synthons [17] are often generated in situ from hydrazonoyl chlorides and trapped with dipolarophiles to give the corresponding ∆ 2 -pyrazolines as a mixture of regioisomers. [18] ∆ 2 -Pyrazolines are of interest due to their biological activity (e.g., as anti-inflammatory agents [19] ), physical applications (e.g., as optical brighteners [20] and fluorescent switches [21] ) and also as starting materials for the synthesis of functionalized cyclic and acyclic compounds; [8a,22] hence procedures to prepare these systems in a regio-and diastereoselective way are of great value.…”

Investigation of the hydrated 7-hydroxy-4-methylcoumarin dimer by combined IR/UV spectroscopy

“…4 In addition, they can act as efficient fluorescence brighteners. 5 The first industrially used optical brightener was 7-hydroxy-4-methylcoumarin. With regard to hydroxycoumarins, especially the biological as well as the pharmaceutical relevance must be discussed: They can, e.g., have anticancer, 6 enzyme inhibitor, 7 or antimicrobial activity.…”

Synthesis of Tetrasubstituted Pyrazoles from Substituted Hydrazines and β‐Keto Esters

“…These key scaffolds display a broad spectrum of biological activities, including antibacterial, anticancer, anti‐inflammatory,[1f], antiviral, analgesic, estrogen‐receptor‐agonistic,[3b] and cannabinoid‐receptor‐antagonistic activities. [6b] They can also act as ligands in coordination complexes and serve as optical brighteners, UV stabilizers, and building blocks in supramolecular assemblies . Apart from their medicinal values, polysubstituted pyrazoles have been utilized for many other purposes, such as ligands for cross‐coupling reactions and dyes …”