Bis-anthrones

The novel bis-anthrones, flavoobscurin A (89), B (90) and B2 (the latter two are rotational isomers) were produced by Anaptychia obscurata... 

In the presence of ZnCla, Michael addition of anthrone (122) to a,/3-unsaturated ketones has been reported to proceed smoothly, producing mono-adducts (123), whereas bis-adducts (124) are formed in basic solution. ... 

Di-9-anthrylethane and related derivatives topology, 144 9-anthraldehyde azines, 153 anthrone derivatives, 148 bis-a-9-anthrylmethyl ethers, 151 dianthrylacetone, 149... 

Electron-impact-induced fragmentation patterns of 2,5-bis(p-dichloromaleimidophenyl) 1,3,4-oxadiazole (compound c) 3,3-bis(p-dichloromaleimidophenyl)phthalide (compound d) and 10,10-bis(p-dichloromaleimidophenyl)anthrone (compound f) are given in Figure 1. The common features present in the mass spectra of these compounds are summarized in Table II. A low-intensity molecular ion peak was observed in most of these monomers, with the exception of compounds (a) and (b). Loss of carbon dioxide from the molecular ion (M-44) was indicated only in compound (d), which contains a phthalide group. Carbon dioxide may be eliminated from this site. Similar fragmentation patterns have earlier been obtained with corresponding bismaleimides and biscitraconimides (15). 

The reactions of thienothiophene derivatives in the absence of a solvent were also described. For example, the solid-state thermally induced rearrangement of 9,10-dihydroxy-9,10-bis(thieno[3,2- >]thiophen-2-yl)-9,10-dihydroanthracene (275) occurs at 240 °C and gives 10,10-bis(thieno[3,2- >]thiophen-2-yl)anthrone (276) (2000JA1082). 

An inspiring example of the bifunctional nature of prolinol compounds as catalysts suitable for cycloaddition reaetions has been disclosed by Kagan, who reported the Diels-Alder reaction of Af-methyl maleimide and anthrone catalysed by prolinol Ic (Scheme 7.13). The product was isolated in excellent yield and with 43% ee. An improvement of the stereocontrol was achieved when using Cj-symmetrie bis(hydroxymethyl) pyrrolidine 7... 

Bis-dimethylamino. 4,10 triory-anthron.(9) i4 II185. N.N Athyliden-di[Pg.1249]

OsgHagOg 10-0xo-9.9-bis-[4-methoxy-phenyl]. Bnthraoen-dihydrid-(9.10) 8, 373. 10.10-Bis-[4-o -3-niethyl-phenyl]-phen> anthrOn-(9) 8 H 429. 

Hsieh et al. (1976a) attempted to incorporate radioactivity into aflatoxin Bi from four tritiated anthraquinone and anthrone derivatives to simulate the proposed C18 compounds (Biollaz et al., 1970). None of the four compounds was readily convertible into aflatoxin Bi. These findings clearly indicated that a Cig naphthacene precursor is no longer tenable. 

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