69180-08-1

Upstream product

• 13076-29-4 1,4-dimethoxyanthracene 
• 75829-98-0 1,4-dimethoxy-9,10-dihydro-9,10-anthracenediol 
• 600736-18-3 4a,9,9a,10-Tetrahydro-5,8-dimethoxy-9,10-<1',2'>benzenoanthracen-1,4-dion 
• 106-51-4 p-benzoquinone 

Relevant academic research and scientific papers

Synthesis and activity on free radical processes and inflammation of 9,10-dihydro-5,8-dimethoxy-triptycene-quinones

Three triptycene quinones bearing methoxy groups were prepared following a Diels-Alder methodology and were evaluated for antioxidant and anti-inflammatory activity bearing in mind their structural features that could justify intervention with free radical processes. Improved synthetic pathways were achieved for target molecules 9,10-dihydro-5,8-dimethoxy-9,10-[o]benzenoanthracene-1,4-dione (4), 9,10-dihydro-2-hydroxy-5,8-dimethoxy-9,10-[o]benzenoanthracene-1,4-dione (6), and 9,10-dihydro-2,5,8-trimethoxy-9,10-[o]benzenoanthracene-1,4-dione (9). Under our experimental conditions these compounds showed very significant antioxidant activity offering protection against lipid peroxidation of rat hepatic microsomal fraction while inhibiting the reaction completely at very low concentrations (12.5-80 μM). Moreover, compound 6 that was examined, inhibited by 44% (at 120 μM) lipoxygenase acitvity while the anti-inflammatory activity of the compounds, as assessed by the reduction of the mouse paw edema induced by Freund's complete adjuvant, was significant and comparable to that of indomethacin.

ESR Spectroscopic Detection of Intramolecular Interactions in Radical Cations of Poly(α-methoxy)triptycenes

-Cycloaddition of 1,4-benzoquinone to the di- and tetra(α-methoxy)anthracenes 11 yields the diketones 12 which undergo an acid-catalyzed rearrangement to the triptycene hydroquinones 13.Methylation of 13 affords the poly(α-methoxy)triptycenes 4.Aluminium chloride in nitromethane oxidizes the triptycenes 4 to the radical cations 4+* having one 1,4-dialkoxybenzene ring (4b+*, 4c+*, 4e+*) or two (4a+*) or three (4d+*), respectively, of such potential radical centers.The protons of the radical center give rise to hyperfine splittings which are very similar to those found in the ESR spectra of simple cis-1,4-dialkoxybenzene radical cations.The other aromatic protons, but not the bridgehead protons, exhibit a long range hyperfine coupling of 0.011 mT.Selective line broadening in the ESR spectrum of the radical cation 4a+* indicates that intramolecular electron transfer between the 1,4-dimethoxybenzene moieties occurs at a moderate rate.The deceleration of the exchange rate compared to the rate expected for a free radical cation is interpreted in terms of ion pairing.