Xanthene

About: Xanthene is a research topic. Over the lifetime, 2132 publications have been published within this topic receiving 34803 citations. The topic is also known as: Xanthene & dibenzo[a,e]pyran.

Alkaline Earth Metal Catalyzed, One‐Pot, Multi‐Component Approach for the Synthesis of Dihydropyridine, Acridine and Xanthene Derivatives in Water.

Abstract: Xanthenediones, acridinediones, and dihydropyridines or Hantzsch esters (Figure 1) are a rich class of biologically active heterocyclic compounds. They possess a spectrum of biological and pharmacological properties such as analgesic 1 , antiviral 2 , antibacterial 3 and antiinflammatory 2 activities, etc. and also they have been employed as important building blocks for the synthesis of many organic molecules 4 . Some of these fused heterocyclic compounds have also been utilized as a fluorescent materials 5 , leuco-dyes 6 , as sensitizers in photodynamic therapy 7 and in laser technology 8 . Due to their broad range of applications, they received tremendous attention from the synthetic community, which resulted in a number of synthetic protocols for their synthesis 9-11 . Broadly, the synthesis involves the thermal-acidic/basic condensation of 1,3-diketones and aldehydes for xanthenes; 1,3-diketones with aldehyde and nitrogen nucleophiles for the dihydropyridine/acridine synthesis. Though a variety of catalytic systems have been developed for the synthesis of xanthenes 9 , acridines 10 and Hantzsch dihydropyridines 11 , some of these protocols suffer from drawbacks such as use of strong acid or base catalysts, large amount of catalyst loadings, poor yields and usage of halogenated solvents for the reactions.

Film, optical memory material using the same film and method for producing the same film

Abstract: PROBLEM TO BE SOLVED: To prepare a film in which a fluorescent material is dispersed in PMMA, to obtain an optical memory material using the film, and to provide a three-dimensional memory using the optical memory material. SOLUTION: The film is composed of at least PMMA (polymethyl methacrylate), a fluorescent material dispersed in the PMMA and having a xanthene skeleton and a lactone ring and/or a fluorescent material having the xanthene skeleton and a COOR group (R is hydrogen atom or a substituent group) capable of forming an intramolecular lactone ring. The optical memory material is obtained by using the film. The three-dimensional memory is obtained by using the optical memory material. COPYRIGHT: (C)2005,JPO&NCIPI

Tracing liquid flow

Abstract: A tablet for tracing the flow of a liquid comprises a dye and an inert carrier. Utility is in tracing liquid flows in drains, sewers or water courses. Typical dye components are Xanthene or Azo dyes.